Microorganisms

J Mol Biol, 1988 Apr 5, 200(3), 611 - 2
Crystallization of haloalkane dehalogenase from Xanthobacter autotrophicus GJ10; Rozeboom HJ et al.; Haloalkane dehalogenases are enzymes that release chloride or bromide from n-halogenated alkanes . X-ray quality crystals of haloalkane dehalogenase from the 1,2-dichloroethane-degrading bacterium Xanthobacter autotrophicus GJ10 have been grown at room temperature from 64% saturated ammonium sulfate solutions (pH 6.2 to 6.4) . The crystals diffract in the X-ray beam to at least 2.4 A resolution (1 A = 0.1 nm) . Their space group is P2(1)2(1)2, with cell dimensions a = 94.1 A, b = 72.8 A, c = 41.4 A and alpha = beta = gamma = 90 degrees . There is one monomer (molecular weight 36,000) per asymmetric unit.

Biochemistry, 1988 Apr 5, 27(7), 2450 - 61
Cytochrome c and c2 binding dynamics and electron transfer with photosynthetic reaction center protein and other integral membrane redox proteins; Moser CC et al.; To further the understanding of the details of c-type cytochrome action as a redox carrier between major electron-transfer proteins, the single-turnover kinetics time course of cytochrome c and cytochrome c2 oxidation by flash-activated photosynthetic reaction center (purified from the bacterium Rhodobacter sphaeroides) has been examined under a wide variety of conditions of concentration, ionic strength, and viscosity with reaction center present in detergent dispersion and phosphatidylcholine proteoliposomes . We find that the three-state model proposed by Overfield and Wraight {Overfield, R . E., & Wraight, C . A . (1980) Biochemistry 19, 3322-3327} is generally sufficient to model the kinetics time course; many similarities are found with the cytochrome c-cytochrome c oxidase interaction in mitochondria . Further, we find the following: (1) Significant "product inhibition" by oxidized cytochrome c (c2) bound to the reaction center is apparent . (2) The viscosity sensitivity of the electron transfer into the reaction center from bound cytochrome c (c2) suggests a physical interpretation of the distal state . (3) The exchange dynamics of oxidized and reduced cytochrome c (c2) are similar regardless of the state of activation of the reaction center . (4) Preferential binding of the oxidized form of cytochrome c is revealed upon reconstitution of the reaction center into neutral lipid vesicles, permitting an independent confirmation of the binding suggested by the kinetics . (5) Flash-activated electron-transfer kinetics in reaction center hybrid protein systems have shown that diffusion and competitive binding characterize the behavior of cytochrome c as a redox carrier between the reaction center protein and either the cytochrome bc1 complex or the cytochrome c oxidase.

Biochemistry, 1988 Apr 5, 27(7), 2444 - 50
A hypothetical model of the flavodoxin-tetraheme cytochrome c3 complex of sulfate-reducing bacteria; Stewart DE et al.; A hypothetical model of the flavodoxin-tetraheme cytochrome c3 electron-transfer complex from the sulfate-reducing bacterium Desulfovibrio vulgaris has been constructed by using interactive computer graphics based on electrostatic potential field calculations and previous NMR experiments . Features of the proposed complex are (1) van der Waals contact between the flavin mononucleotide prosthetic group of flavodoxin and one heme of the cytochrome, (2) unique complementarity of electrostatic fields between the region surrounding this heme and the region surrounding the exposed portion of the flavin mononucleotide group of flavodoxin, and (3) no steric interferences between the two polypeptide chains in the complex . This complex is consistent with all structural and spectroscopic data available.

J Biol Chem, 1988 Apr 5, 263(10), 4602 - 6
Actinomycin synthesis in Streptomyces antibioticus . Purification and properties of a 3-hydroxyanthranilate 4-methyltransferase; Fawaz F et al.; A methyltransferase, which utilizes 3-hydroxyanthranilic acid (HAA) as a substrate, has been purified to near homogeneity from 30-36-h mycelium of the bacterium Streptomyces antibioticus . The enzyme was obtained in approximately 20% yield with a purification of 130-fold . Polyacrylamide gel electrophoresis under denaturing conditions indicates that the enzyme is composed of a single subunit with Mr of about 36,000 . On chromatography in 0.5 M NaCl, the enzyme displays a molecular weight of about 37,000 . The specific activity of the enzyme in S . antibioticus mycelium is maximal between 30 and 36 h following inoculation of galactose/glutamic acid medium and, at those times post-inoculation, the specific activity is essentially the same in extracts of mycelium obtained from cultures grown on glucose rather than galactose as the carbon source . The enzyme activity is stimulated by Na2EDTA (in crude extracts) and by 2-mercaptoethanol and the methyltransferase shows a strong preference for HAA as substrate as compared with a number of HAA analogs . Thin layer chromatography of ethyl acetate extracts of large-scale incubation mixtures confirms that the product of the reaction is 4-methyl-3-hydroxyanthranilic acid . The reaction product was also a substrate for phenoxazinone synthase and was incorporated into actinomycin by S . antibioticus mycelium . Kinetic parameters for the methyltransferase reaction was determined.

Microbiologica, 1988 Apr, 11(2), 169 - 71
Isolation of Erysipelothrix rhusiopathiae from a 55 year old man and a positive tracing of the infection to chicken-raising premise; Salamah AA; Erysipelothrix rhusiopathiae was isolated from the swollen finger of a 55 year old man . The swelling was due to a peck by an infected chicken . Tracing the infection to the chicken-raising premises has proven that the bacterium was present in some of the chicken and manure samples.

Int J Clin Pharmacol Ther Toxicol, 1988 Apr, 26(4), 199 - 203
A study of the levels of tobramycin and gentamicin in human serum and renal cortex and of changes in in vitro bacterial sensitivity; Farago E et al.; Concentration of gentamicin and tobramycin in sera and renal tissue was determined . Though between the 2nd and 6th day of the treatment, gentamicin cumulated in the renal tissue, but it did not reach toxic value . Tobramycin did not show cumulation tendency . According to in vitro bacterium sensitivity studies, the wide scale use of tobramycin in the clinical practice caused the sudden increase of resistance . To avoid this, the rules of antibiotic treatment should be observed.

Appl Environ Microbiol, 1988 Apr, 54(4), 937 - 44
Mineralization of phenanthrene by a Mycobacterium sp; Guerin WF et al.; A Mycobacterium sp., designated strain BG1, able to utilize the polycyclic aromatic hydrocarbon phenanthrene as the sole carbon and energy source was isolated from estuarine sediment following enrichment with the hydrocarbon . Unlike other phenanthrene degraders, this bacterium degraded phenanthrene via 1-hydroxy-2-naphthoic acid without accumulating this or other aromatic intermediates, as shown by high-performance liquid chromatography . Degradation proceeded via meta cleavage of protocatechuic acid . Different nonionic surfactants (Tween compounds) solubilized the phenanthrene to different degrees and enhanced phenanthrene utilization . The order of enhancement, however, did not correlate perfectly with increased solubility, suggesting physiological as well as physicochemical effects of the surfactants . Plasmids of approximately 21, 58, and 77 megadaltons were detected in cells grown with phenanthrene but not in those which, after growth on nutrient media, lost the phenanthrene-degrading phenotype . Given that plasmid-mediated degradations of aromatic hydrocarbons generally occur via meta cleavages, it is of interest that the addition of pyruvate, a product of meta cleavage, supported rapid mineralization of phenanthrene in broth culture; succinate, a product of ortho cleavage, supported growth but completely repressed the utilization of phenanthrene . The involvement of plasmids may have given rise to the unusual degradation pattern that was observed.

J Bacteriol, 1988 Apr, 170(4), 1709 - 14
Purification and properties of benzoate-coenzyme A ligase, a Rhodopseudomonas palustris enzyme involved in the anaerobic degradation of benzoate; Geissler JF et al.; A soluble benzoate-coenzyme A (CoA) ligase was purified from the phototrophic bacterium Rhodopseudomonas palustris . Synthesis of the enzyme was induced when cells were grown anaerobically in light with benzoate as the sole carbon source . Purification by chromatography successively on hydroxylapatite, phenyl-Sepharose, and hydroxylapatite yielded an electrophoretically homogeneous enzyme preparation with a specific activity of 25 mumol/min per mg of protein and a molecular weight of 60,000 . The purified enzyme was insensitive to oxygen and catalyzed the Mg2+ ATP-dependent formation of acyl-CoA from carboxylate and free reduced CoA, with high specificity for benzoate and 2-fluorobenzoate . Apparent Km values of 0.6 to 2 microM for benzoate, 2 to 3 microM for ATP, and 90 to 120 microM for reduced CoA were determined . The reaction product, benzoyl-CoA, was an effective inhibitor of the ligase reaction . The kinetic properties of the enzyme match the kinetics of substrate uptake by whole cells and confirm a role for benzoate-CoA ligase in maintaining entry of benzoate into cells as well as in catalyzing the first step in the anaerobic degradation of benzoate by R . palustris.

J Bacteriol, 1988 Apr, 170(4), 1438 - 44
The methanoreductosome: a high-molecular-weight enzyme complex in the methanogenic bacterium strain Gö1 that contains components of the methylreductase system; Mayer F et al.; The methanogenic bacterium strain Go1 harbors a high-molecular-weight enzyme complex containing methyl coenzyme M methylreductase as revealed by immunoelectron microscopy . This complex consists of a spherelike, hollow head piece, in the wall of which a number of copies of the methyl coenzyme M methylreductase are located . It is named Rc (c indicates collector) . Intimately bound to it is a group of additional subunits of unknown composition referred to as Rm (m indicates mediator) . Electron microscopy of negatively stained samples indicated that Rm contains a functional pore or channel which connects the internal volume of Rc with the outside . The RcRm complex is named Rs (s indicates spherelike) . This complex was often found detached from the inside of the cytoplasmic membrane when membrane vesicles were investigated . However, Rs was also seen attached to a third component of the complex located in the membrane, the attachment being mediated by Rm . This membrane part of the complex is designated Rt (t indicates translocator) . It consists of subunits with unknown composition . When Rs is attached to the membrane, the pore in Rm appears to be plugged by Rt . This indicates that the internal volume in Rc is in contact, via the pore in Rm, with Rt . The RcRmRt complex is referred to as methanoreductosome . Functional implications of the structural organization of the methylreductase system are discussed in view of methane formation and the creation of a transmembrane proton gradient used by the cell for ATP synthesis.

J Bacteriol, 1988 Apr, 170(4), 1843 - 7
Roles of bacteriochlorophyll and carotenoid synthesis in formation of intracytoplasmic membrane systems and pigment-protein complexes in an aerobic photosynthetic bacterium, Erythrobacter sp . strain OCh114; Iba K et al.; Synthesis of bacteriochlorophyll and carotenoids was inhibited in an aerobic photosynthetic bacterium, Erythrobacter sp . strain OCh114, by alpha, alpha'-dipyridyl and diphenylamine . Formation of two pigment-protein complexes, reaction center-B870 (RC-B870) and B806, and development of the intracytoplasmic membranes of the cells were studied by spectral analysis and electron microscopy . Inhibition of bacteriochlorophyll synthesis by alpha, alpha'-dipyridyl, which was accompanied by a decrease in carotenoid synthesis, suppressed formation of intracytoplasmic membranes in the cells . Growth under illumination had a similar effect on formation of pigments and membranes . On the other hand, inhibition of carotenoid synthesis by diphenylamine did not suppress either development of the membrane system or bacteriochlorophyll synthesis . Formation of RC-B870 and B806 complexes, however, was differentially affected by blockage of carotenoid synthesis . In the presence of diphenylamine, the B806 complex was formed in a much smaller amount than the RC-B870 complex . These results suggest that, in Erythrobacter sp . strain OCh114, bacteriochlorophyll plays an essential role in intracytoplasmic membrane development, and carotenoids are important for assembly of pigment-protein complexes.

Biochimie, 1988 Apr, 70(4), 503 - 17
Strategies for the development of bacterial transformation systems; Mercenier A et al.; An effective transformation system is a prerequisite for facile genetic manipulation of bacteria . Bacteria may be naturally competent for transformation or may be treated with various agents, such as Tris buffers or divalent metal ions, to induce competence . Transformation can also be accomplished by electroporation, or by fusion of protoplasts with PEG in the presence of transforming DNA . Unfortunately, the mechanism by which cells become permeable to DNA and the process by which DNA enters the cells is frequently unknown . In order to establish a transformation system for an untransformable bacterium, recipient strains and transforming DNA must be carefully selected . Since it is impossible to predict in advance which method of transformation will be successful with a particular bacterial strain, several techniques are usually evaluated . This review describes a number of factors that appear to be critical for developing a transformation system and presents a strategy for experimentation with novel bacteria.

J Antibiot (Tokyo), 1988 Apr, 41(4), 433 - 8
Novel macrocyclic antibiotics: megovalicins A, B, C, D, G and H . I . Screening of antibiotics-producing myxobacteria and production of megovalicins; Miyashiro S et al.; New antibiotics belonging to macrocyclic were discovered and named megovalicins A, B, C, D, G and H . The antibiotics were accumulated endogeneously by a newly isolated myxobacterium identified as Myxococcus flavescens . Tank culture of the bacterium for 4 days gave 8.8 g cells/liter on a wet basis, and 4.8, 7.1, 20.0, 0.4, 3.75 and 15.0 micrograms of megovalicins A, B, C, D, G and H respectively were obtained from 1 g wet cells.

Indian J Lepr, 1988 Apr, 60(2), 159 - 72
Evaluation of an enzyme immunoassay based on sonicate supernatant antigens of Mycobacterium w for immunodiagnosis of leprosy; Moudgil KD et al.; An enzyme immunoassay (EIA) based on sonicate supernatant antigens of a cultivable, atypical bacterium, Mycobacterium w (M . w), for immunodiagnosis of leprosy is described . M . w was selected after screening of sonicate supernatant antigens of seven cultivable mycobacteria in EIA . The results of the assay were compared with that of EIA using phenolic glycolipid-I (PGL-I) . The M . w assay was more sensitive than PGL-I based EIA, for detection of leprosy patients of all categories, including long term treated patients with low bacterial load . The M . w assay was highly sensitive (93.49%) for detection of active LL patients, and the difference in the positivity of the two assays for LL patients was statistically significant (p 0.05) . The combined positivity of the assays with M . w and PGL-I for LL was higher than that with either antigen alone . M . w assay, in addition, was also highly sensitive for detection of patients with active pulmonary tuberculosis.

J Biol Chem, 1988 Mar 25, 263(9), 4374 - 80
Surface-enhanced resonance Raman scattering spectroscopy of bacterial photosynthetic membranes . The carotenoid of Rhodospirillum rubrum; Picorel R et al.; Resonance Raman scattering by the carotenoid, spirilloxanthin (Spx), in a suspension of chromatophores (cytoplasmic side out) isolated from the photosynthetic bacterium, Rhodospirillum rubrum, is greatly enhanced when the membranes are adsorbed onto the surface of an anodized Ag electrode . The phenomenon is the basis for surface-enhanced resonance Raman scattering (SERRS) spectroscopy . The Spx SERRS peaks observed were at 1505-1510, 1150-1155, and 1000-1005 cm-1 with laser excitation wavelengths ranging between 457.9 and 568.2 nm . Similar peaks were not observed with spheroplasts (periplasmic side out) isolated from the same species . The difference in signal detected in chromatophores and spheroplasts is not due to differences in membrane surface charge, presence of residual cell wall on the spheroplast surface, lack of adhesion of spheroplasts to metals, or large differences in pigment content per unit membrane area . Instead, the results indicate an asymmetric distribution of Spx in vivo across the membrane (i.e., it is located on the cytoplasmic side of the membrane) . The results also demonstrate that the SERRS effect is extremely distance sensitive, and the thickness of a single bacterial membrane (separating the Ag electrode from the carotenoid) is sufficient to prevent detection of Spx spectra . Studies of chromatophores from the F24 strain (a reaction centerless mutant) have pin-pointed B880 antenna complex as the source of the Spx SERRS spectra, and a schematic model of the minimal structural unit of B880 is presented . This work demonstrates the potential of the SERRS technique as a probe for surface topology of pigmented membranes.

Derm Beruf Umwelt, 1988 Mar-Apr, 36(2), 39 - 44
{The spectrum of Lyme borreliosis from the dermatologic viewpoint}; Aberer E et al.; Erythema chronicum migrans, lymphadenosis benigna cutis and acrodermatitis chronica atrophicans represent the dermatological manifestations of the multi-organ disease Lyme borreliosis . Koch's requirements of evidence for an infectious disease, demonstration of the bacterium, transfer, and culture have proven Borrelia burgdorferi to be the causative agent of the above mentioned skin diseases . This justifies a penicillin therapy, that has been administered in Europe empirically for the last 30 years . Correct and prompt diagnosis is important since delayed treatment is less effective, presumably because the spirochete becomes sequestered in immune-privileged sites . Recent observations in several laboratories that antibody titers to Borrelia burgdorferi are also elevated in several other skin diseases and that the spirochete can be detected in tissue sections of different organs may imply extension of the dermatological spectrum of Lyme disease . The significance of these findings in such heterogeneous diseases as morphea, lichen sclerosus et atrophicans, etc . however awaits final examination.

Eur J Biochem, 1988 Mar 1, 172(2), 413 - 9
Amino acid sequence determination and three-dimensional modelling of thioredoxin from the photosynthetic bacterium Rhodobacter sphaeroides Y; Clement-Metral JD et al.; The complete primary structure of thioredoxin from Rhodobacter sphaeroides Y has been determined by analysis of peptides after cleavage with cyanogen bromide, chymotrypsin and trypsin . Peptides were separated by HPLC and analyzed by liquid-phase and gas-phase sequencer degradations . The protein consists of 105 residues (Mr = 11,180); its amino acid sequence shows a clear homology to the five known thioredoxins from plant or bacterial sources, with 40-56% residue identity when the proteins are aligned at the active-site disulfide . Not only the active-site regions are conserved, but also residues which belong to the hydrophobic surface suggested to be important for binding of procaryote thioredoxins in redox interactions with other proteins (residues 75-76; 91-93 in Escherichia coli) . A three-dimensional model of Rb . sphaeroides thioredoxin has been derived from the E . coli crystallographic structure with computer graphics . This model indicates that the overall structures as well as the active sites are closely similar; however, the residue substitutions allow both proteins to adopt different local folding as shown in the hydrophobic core.

Acta Eur Fertil, 1988 Mar-Apr, 19(2), 93 - 7
The incidence of Chlamydia trachomatis-induced infection in women suffering from cervicovaginitis; Pungetti D et al.; The results of a research on Chlamydia T . (direct survey of both the antigen in the uterine cervix and plasmatic antibodies) in a group of subjects suffering for cervico-vaginitis are provided . The incidence of the Chlamydia infection (proved by either the presence of this bacterium or antibody positivity) is not different from the values reported in literature . Conversely, the presence of neither specific cytological or colposcopic patterns nor of priviledged comites at vaginal level could be demonstrated . Our data, however, confirm a greater incidence of this infection in women reporting early sexual life and a high number of partners . As for the relationship between Chlamydia and contraceptives a slightly higher incidence of positivity in the cervix of patients using oestro-progestinics was registered, whereas no significant difference was noted in the use of other contraceptives IUD includedPIP: Physicians examined 173 sexually active, non pregnant women suffering from lower genitalia inflammation . They responded to questions pertaining to their past and recent obstetric/gynecological history, to their partner's possible urogenital inflammations, the age of 1st intercourse, number of partners, and contraceptive use . 27.2% of the patients tested positive using immunoenzymatic techniques for Chlamydia trachomatis (CT) . No specific symptoms of CT were observed . A correlation exists between early sexual intercourse and a large number of partners and a greater incidence of CT infections . Almost 98% of all CT positive patients reported 1st sexual intercourse between 16 and 21 years . Antibody positivity ranged from 33% (1st intercourse before 15 years) to 24% (1st intercourse between 16-21 years) and decreased to 5.89% when 1st intercourse occurred 21 years . In addition, CT positive patients had many partners . A greater positivity in the cervix occurred in those using oral contraceptives, however . On the other hand, no positivity was noted for those who used IUDs . Those women who used several contraceptives, such as oral contraceptives, IUD, and barrier methods, had a higher incidence of CT positivity (53.2%) than other groups . Perhaps this is due to clinical cervicovaginitis symptoms prompting the women to change techniques . Specific colposcopy patterns and cytological alterations which some physicians believe indicate CT infections did not identify patients with Chlamydia . These data suggest that it is impossible to make a diagnosis based on symptoms, past sexual history, and contraceptive use . Therefore the data indicate that immunoenzymatic tests are needed .

Can J Microbiol, 1988 Mar, 34(3), 287 - 98
The role of bacterial hydrophobicity in infection: bacterial adhesion and phagocytic ingestion; Absolom DR; The role that bacterial surface hydrophobicity (surface tension) plays in determining the extent of adhesion of polymer substrates and phagocytic ingestion is reviewed . The early attachment phase in bacterial adhesion is shown to depend critically on the relative surface tensions of the three interacting phases; i.e., bacteria, substrate, and suspending liquid surface tension . When suspended in a liquid with a high surface tension such as Hanks balanced salt solution, the most hydrophobic bacteria adhere to all surfaces to the greatest extent . When the liquid surface tension (gamma LV) is larger than the bacterial surface tension (gamma BV), then for any single bacterial species the extent of adhesion decreases with increasing substrate surface tension (gamma SV) . When gamma LV less than gamma BV then adhesion increases with increasing gamma SV . Bacterial surface tension also determines in part the extent of phagocytic ingestion and the degree to which antibodies specifically adsorb onto the bacterium resulting in opsonization . The nonspecific adsorption of antibodies results in a considerable modification in the surface properties of the bacteria . Bacterial surface hydrophobicity can be altered significantly through exposure to subinhibitory concentrations of antibiotics, surfactants, lectins, etc . The effect of these changes on subsequent phagocytic ingestion is discussed.

Infect Immun, 1988 Mar, 56(3), 673 - 81
Appearance of sialoglycoproteins in encysting cells of Entamoeba histolytica; Chayen A et al.; Amoeba-bacterium cultures of Entamoeba histolytica transferred to a hypoosmotic medium depleted of nutrients changed morphologically and biochemically . The cells ejected grains of rice starch, rounded up, and formed a distinct cell wall that was resistant to detergent, bound the sialic acid-specific lectin from Limulus polyphemus, and became fluorescent with Calcofluor M2R . A subpopulation of these cells displayed more than one nucleus . All these signs are characteristic of encysting cells and were also observed in cysts obtained from a human patient . The morphological changes were accompanied by the appearance of two new glycoproteins with apparent molecular sizes of 100 and 150 kilodaltons which contained sialic acid . Sialic acid has been reported to be absent from trophozoites of Entamoeba species . The presence of this sugar residue on cyst-specific proteins parallels recently reported findings during the encystation of the related reptilian parasite Entamoeba invadens . This may indicate a basic role for sialic acid in the encystation of Entamoeba parasites.

Cell, 1988 Feb 26, 52(4), 599 - 607
At least three different RNA polymerase holoenzymes direct transcription of the agarase gene (dagA) of Streptomyces coelicolor A3(2); Buttner MJ et al.; Using a combination of gel filtration and anion exchange FPLC, three different RNA polymerase holoenzymes from Streptomyces coelicolor A3(2) have been separated . Each holoenzyme transcribes from only one of the four promoters of the S . coelicolor A3(2) dagA gene . Holoenzyme reconstitution experiments identified the sigma factors responsible for recognition of two of the promoters . The previously identified E sigma 49 transcribes from the dagA p3 promoter, whereas a novel species, E sigma 28, recognizes the dagA p2 promoter . Circumstantial evidence suggests that the third holoenzyme, which transcribes from the dagA p4 promoter, is the previously identified E sigma 35 . This level of transcriptional complexity supports the idea that RNA polymerase heterogeneity may play a central role in the regulation and coordination of gene expression in this biochemically and morphologically complex bacterium.

J Immunol, 1988 Feb 15, 140(4), 1022 - 7
IFN-gamma regulates the isotypes of Ig secreted during in vivo humoral immune responses; Finkelman FD et al.; The lymphokine IFN-gamma has been shown in vitro to stimulate IgG2a secretion and inhibit IgG1 and IgE secretion by LPS-activated B lymphocytes . To determine whether IFN-gamma has a similar isotype regulatory role in vivo, we studied the abilities of rIFN-gamma and a mAb to IFN-gamma to modify the isotypes of Ig secreted in mice injected with a goat antibody to mouse IgD, which by itself induces large increases in levels of serum IgG1 and IgE and a relatively small increase in serum IgG2a . Multiple injections of IFN-gamma substantially inhibited production of IgG1 and IgE, and stimulated production of IgG2a in affinity purified goat antibody specific for mouse IgD-treated mice; anti-IFN-gamma antibody blocked the effects of IFN-gamma and in fact enhanced IgG1 and IgE secretion and inhibited the IgG2a response in these mice . The role of IFN-gamma in the selection of isotypes of Ig produced in response to injection of mice with the bacterium Brucella abortus (BA) was also studied, because killed, fixed BA are known to stimulate IFN secretion and a predominantly IgG2a antibody response . Anti-IFN-gamma antibody strongly suppressed IgG2a secretion and stimulated IgG1, but not IgE, secretion in BA-immunized mice . BA suppressed IgG1 and IgE secretion and enhanced IgG2a secretion in affinity purified goat antibody specific for mouse IgD-injected mice; treatment of these mice with anti-IFN-gamma antibody reversed the effects of BA on IgG1 and IgG2a secretion, but not the suppressive effect of BA on IgE secretion . These observations demonstrate that IFN-gamma has an important and perhaps unique physiologic role in the stimulation of IgG2a secretion and in the suppression of secretion of IgG1, whereas bacterial antigens can suppress IgE secretion by other mechanisms in addition to IFN-gamma secretion.

Infect Immun, 1988 Feb, 56(2), 395 - 9
Effect of dietary restriction on total and bacterium-specific mucosal secretory immunoglobulin A in bile-diverted intestinal self-filling blind loops; Lichtman SN et al.; The effect of starvation on the mucosal secretory immunoglobulin A (sIgA) response to bacterial antigens was studied in bile-free rat self-filling blind loops constructed at the end of a Roux-en-Y branch of jejunum . Rats were fed a 50% restricted diet for 1 to 4 weeks after surgery . sIgA was measured in the mucosa and lumen by an enzyme-linked immunosorbent assay . Dietary restriction caused a final rise of luminal sIgA which was less than 50% of that of normally fed controls Luminal bacteria counts were not different in the two groups . The percentage of total sIgA precipitated with intestinal bacteria was not significantly affected by dietary restriction, and there was no change in the specific binding of sIgA to several bacterial species . Nonprecipitated sIgA exhibited a low but significant specific binding to bacteria in both diet-restricted and fed rats . Diet restriction therefore reduced the total sIgA response to luminal bacteria, but the specific bacterial binding capacity per microgram of sIgA was not altered . In these short-term experiments diet-restricted animals appeared to be capable of secreting sIgA in excess of requirement, since the nonprecipitable luminal fraction contained free sIgA with binding capacity for bacteria . The ability of sIgA to react with specific antigens may therefore be of more significance as an indicator of bacterial susceptibility than the measurement of total sIgA.

J Gen Virol, 1988 Feb, 69 ( Pt 2), 385 - 93
Transcriptional mapping of the bacteriophage Mu DNA; Barron C et al.; The transcription of temperate phage Mu throughout lytic development was analysed quantitatively by hybridization of pulse-labelled RNA to full-length Mu DNA and to plasmids that define Mu DNA segments covering the whole phage genome . The transcription rate (i.e . binding data corrected for the incorporation rate of the radioactive precursor, for the size of the DNA template, and for the number of phage genomes present in the bacterium at the time of analysis) revealed three defined phases of Mu transcription: early (0 to 9 min), intermediate (between 9 and the interval 14 to 17 min) and late (from the interval 14 to 17 min onward) . The analysis also revealed that the region comprising the genes involved in phage morphogenesis was organized into two independent 'late' transcription units.

J Bioenerg Biomembr, 1988 Feb, 20(1), 41 - 58
Molecular genetics of F1-ATPase from Escherichia coli; Futai M et al.; We have reviewed recent molecular biological studies on F1-ATPase of Escherichia coli and emphasized the advantages of using the bacterium in studies on this important enzyme . All subunits had homologies of varied degrees with those from other organisms . Mutations of F1 subunits caused defects in catalysis and assembly . Defects of the mutant enzymes were studied extensively together with the determination of the amino acid substitutions . Extensive molecular biological studies may help greatly in understanding the normal mechanism and assembly of the complex.

Histochem J, 1988 Feb, 20(2), 108 - 16
Pitfalls in ecto-5'-nucleotidase enzyme cytochemistry as demonstrated by the immunogold-labelling technique on macrophages; Cramer EM et al.; We have used both the enzyme cytochemical method with lead nitrate as a capture agent and an immunological method at the electron microscope level to localize plasma membrane 5'-nucleotidase in rat peritoneal resident macrophages during the initial interactions of latex beads or heat-killed Escherichia coli with the cell during phagocytosis . In macrophages at rest, cytochemical reaction product was evenly distributed along the external surface of the plasma membrane . However, when the cells were phagocytosing latex beads or bacteria, reaction product covered the entire surface of the adhering particles . To determine whether the apparent redistribution of 5'-nucleotidase onto the adhering particle was fact or artifact, we localized 5'-nucleotidase using a monoclonal antibody and an immunogold labelling technique . In macrophages binding or beginning to ingest bacteria, gold particles were distributed along the plasma membrane, except at the sites of cell-bacterium internalization . More significantly, the adhering bacteria were free of gold particles and therefore had no 5'-nucleotidase on their surfaces . Latex beads proved to be unsuitable as a test particle because the gold particles stuck to them non-specifically . We conclude that the artifactual redistribution of lead-phosphate reaction product is a major drawback of enzyme cytochemical methods when used on cell surfaces and that the immunogold labelling technique is more reliable.

Eur J Biochem, 1988 Jan 15, 171(1-2), 67 - 72
Purification and characterization of a bacterial dehalogenase with activity toward halogenated alkanes, alcohols and ethers; Janssen DB et al.; An enzyme that is capable of hydrolytic conversion of halogenated aliphatic hydrocarbons to their corresponding alcohols was purified from a 1,6-dichlorohexane-degrading bacterium . The dehalogenase was found to be a monomeric protein of relative molecular mass 28,000 . The affinity for its substrates was relatively low with Km values for short-chain haloalkanes in the range 0.1-0.9 mM . The aliphatic dehalogenase showed a much broader substrate range than has been reported for halidohydrolases so far . Novel classes of substrates include dihalomethanes, C5-C9 1-halo-n-alkanes, secondary alkylhalides, halogenated alcohols and chlorinated ethers . Several of these compounds are important environmental pollutants, e.g . methylbromide, dibromomethane, 1,2-dibromoethane, 1,3-dichloropropene, and bis(2-chloroethyl)ether . The degradation of chiral 2-bromoalkanes appeared to proceed without stereochemical preference . Optically active 2-bromobutane was converted with inversion of configuration at the chiral carbon atom, suggesting that the dehalogenase reaction proceeds by a nucleophilic substitution involving a carboxyl group or base catalysis.

Eur J Biochem, 1988 Jan 15, 171(1-2), 245 - 52
The hopanoids of the purple non-sulfur bacteria Rhodopseudomonas palustris and Rhodopseudomonas acidophila and the absolute configuration of bacteriohopanetetrol; Neunlist S et al.; Five complex hopanoids have been detected in the purple non-sulfur bacterium Rhodopseudomonas acidophila . Next to the polyfunctionalized methylcyclopentane bacteriohopanetetrol ether already isolated from Methylobacterium organophilum, 35-carbamoylbacteriohopane-32,33,34-triol, 34,35-dicarbamoylbacteriohopane-32,33-diol and two nucleoside analogues, (22R)-30-(5'-adenosyl)hopane and (22S)-30-(5'-adenosyl)hopane were isolated and identified by spectroscopic and chemical methods . In Rhodopseudomonas palustris, however, only 35-amino-bacteriohopane-32,33,34-triol was detected . Chemical correlation between adenosylhopane and bacteriohopanetetrol, as well as comparison of derivatives obtained from bacterial and synthetic hopanoids, permitted the determination of the configurations of all asymmetric centres of the side-chain of bacteriohopanetetrol as 22R, 32R, 33R and 34S . According to the stereochemistry, this side-chain could be a D-ribose derivative linked through its C-5 carbon atom to the hopane skeleton.

Eur J Biochem, 1988 Jan 15, 171(1-2), 351 - 4
Engineered rat insulin I analogue having a B16 Tyr/Asp replacement exhibits unchanged susceptibility to cleavage by insulin proteinase; Varley JM et al.; An analogue of rat insulin I was produced by oligonucleotide-directed mutagenesis of a cloned rat preproinsulin I cDNA, followed by expression of a resulting mutant gene in Escherichia coli K-12 and proteolytic cleavage of mutant proinsulin isolated from this bacterium . The Tyr-to-Asp replacement at residue B16 in the insulin analogue had been expected to diminish the rate of cleavage of the molecule by the enzyme insulin proteinase, since the bond TyrB16-LeuB17, invariant in all mammalian species, had been proposed by other authors as one of the early, major sites of proteolytic attack . In the event the substitution had no measurable effect on the rate of degradation by insulin proteinase . Thus we find no support in these experiments for the hypothesis that the site in question is of primary importance in the degradation of rat insulin I by the enzyme.

Br J Rheumatol, 1988, 27 Suppl 2, 32 - 3
Cross-reactivity studies on bacteria believed to be associated with inflammatory bowel disease (IBD), ankylosing spondylitis (AS) and reactive arthritis (ReA); Pease PE et al.; Six bacteria believed to be associated with IBD and/or AS and ReA were investigated for antigenic cross-reactivity using an ELISA . Considerable degrees of cross-reactivity were detected and it is suggested that if bacterial antigens are involved aetiologically in the diseases, no specific bacterium is concerned.

J Biochem (Tokyo), 1988 Jan, 103(1), 121 - 5
Purification and characterization of ferredoxin from Desulfovibrio vulgaris Miyazaki; Ogata M et al.; Two ferredoxins, Fd I and Fd II, were isolated and purified from Desulfovibrio vulgaris Miyazaki . The major component, Fd I, is an iron-sulfur protein of Mr 12,000, composed of two identical subunits . The absorption spectra of Fd I and Fd II have a broad absorption shoulder near 400 nm characteristic of iron-sulfur proteins . The purity index, A400/A280, of Fd I is 0.69, and its millimolar absorption coefficient at 400 nm is 3.73 per Fe . It contains two redox centers with discrete redox behaviors . The amino acid composition and the N-terminal sequence of Fd I are similar to those of Fd III of Desulfovibrio africanus Benghazi and Fd II of Desulfovibrio desulfuricans Norway . Fd I does not serve as an electron carrier for the hydrogenase of D . vulgaris Miyazaki, but it serves as a carrier for pyruvate dehydrogenase of this bacterium . The evolution of H2 from pyruvate was observed by a reconstructed system containing purified hydrogenase, cytochrome C3, Fd I, partially purified pyruvate dehydrogenase, and CoA . The H2-sulfite reducing system can be reconstructed from the purified hydrogenase, cytochrome C3, Fd I and desulfoviridin (sulfite reductase), but the reaction rate is very slow compared to that of the crude extract at the same molar ratio of the components.

J Wildl Dis, 1988 Jan, 24(1), 176 - 7
Actinobacillosis in free-ranging snowshoe hares (Lepus americanus) from Alaska; Zarnke RL et al.; Actinobacillus capsulatus was isolated from lung, liver, and/or spleen tissue of three snowshoe hares (Lepus americanus) in Alaska . This is the first report of the isolation of this bacterium from free-ranging hares . Actinobacillus capsulatus may have a negative impact on the population density of hares.

Appl Environ Microbiol, 1988 Jan, 54(1), 153 - 7
Existence of a new type of sulfite oxidase which utilizes ferric ions as an electron acceptor in Thiobacillus ferrooxidans; Sugio T et al.; A new type of sulfite oxidase which utilizes ferric ion (Fe3+) as an electron acceptor was found in iron-grown Thiobacillus ferrooxidans . It was localized in the plasma membrane of the bacterium and had a pH optimum at 6.0 . Under aerobic conditions, 1 mol of sulfite was oxidized by the enzyme to produce 1 mol of sulfate . Under anaerobic conditions in the presence of Fe3+, sulfite was oxidized by the enzyme as rapidly as it was under aerobic conditions . In the presence of o-phenanthroline or a chelator for Fe2+, the production of Fe2+ was observed during sulfite oxidation by this enzyme under not only anaerobic conditions but also aerobic conditions . No Fe2+ production was observed in the absence of o-phenanthroline, suggesting that the Fe2+ produced was rapidly reoxidized by molecular oxygen . Neither cytochrome c nor ferricyanide, both of which are electron acceptors for other sulfite oxidases, served as an electron acceptor for the sulfite oxidase of T . ferrooxidans . The enzyme was strongly inhibited by chelating agents for Fe3+ . The physiological role of sulfite oxidase in sulfur oxidation of T . ferrooxidans is discussed.

Biomed Biochim Acta, 1988, 47(6), 537 - 42
Polyclonal IgG synthesis of mononuclear cells induced by the homopolymer of 4,6-dideoxy-4-formamido-alpha-D-mannopyranosyl units isolated from Brucella melitensis; Montag T et al.; Brucella melitensis attaches selectively to B lymphocytes . The bacterium induces in vitro only a slight proliferation of mononuclear cells and inhibits the spontaneous IgG synthesis . In order to characterize these effects, the O-chain of the lipopolysaccharide of Brucella melitensis (a polysaccharide consisting of poly-4,6-dideoxy-4-formamido-alpha-D-mannoside) was prepared and its influence on lymphocyte functions tested . This compound had no effect on blast transformation whereas IgG synthesis of the cells was stimulated more than tenfold by the addition of the Brucella polymannoside.

Proteins, 1988, 3(3), 184 - 6
Crystallization and preliminary X-ray diffraction study of a protein with a high potential rubredoxin center and a hemerythrin-type Fe center; Sieker LC et al.; A newly discovered iron-containing protein, isolated from the bacterium Desulfovibrio vulgaris (Hildenborough, NCIB 8303), has been crystallized . The molecule appears to be a dimer of mass 44kDa . This protein has iron centers with spectrascopic similarities to those in rubredoxins and in hemerythrins . The X-ray diffraction shows symmetry consistent with space group I222 or I212121 . Cell parameters are a = 49.2 A, b = 81.3 A, c = 100.1 A, and alpha, beta, gamma = 90 degrees . X-ray diffraction data have been collected to 3.0 A, and a search for useful heavy atom derivatives is in progress for the analysis of the crystal structure of this Fe-protein.

Antonie Van Leeuwenhoek, 1988, 54(6), 483 - 96
Bilophococcus magnetotacticus gen . nov . sp . nov., a motile, magnetic coccus; Moench TT; The morphological, biochemical, and magnetotactic properties of a single magnetic bacterium are reported . Although this bacterium has not been cultured axenically, the unusual magnetotactic behavior has allowed the collection of cell material of sufficient quantity and purity to allow characterization . The results indicate that this organism represents a new genus of colorless, sulfur-depositing bacteria, albeit of uncertain affiliation . The name proposed for this new genus/species, Bilophococcus magnetotacticus, reflects the most distinctive traits of morphology, motility, and magnetic mineral formation . Classification is based on type descriptive material.

Adv Virus Res, 1988, 35, 219 - 49
Viral-bacterial synergistic interaction in respiratory disease; Babiuk LA et al.; In the present review we have identified how viruses can alter the host's susceptibility to bacterial infections by altering both environmental conditions in the lung which favor bacterial replication as well as by suppressing the host's defense mechanisms which prevent clearance of the bacteria . In many instances, these interactions are extremely complex but similar for many viruses . If the virus can overcome the initial host defense mechanisms, which include local antibody and mucus, the virus initiates tissue damage as a result of direct replication within the epithelial cells lining the mucosal surfaces of the respiratory tract . As a result of virus infection, the host cells respond by producing a variety of mediators including various types of interferons, which can alter both virus replication and host response . Replication also produces by-products of virus infection capable of initiating an inflammatory process, which in turn, through release of other mediators, can further modify lung defense mechanisms and encourage bacterial adherence and growth . The bacterium, in turn, releases chemotactic factors which encourage infiltration of specific effector cells into the lung . These effector cells can cause tissue damage and immunopathology, which encourage rapid bacterial growth and may result in death of the animal . In order to be able to control this complicated scenario, it is important either to prevent the initial infection with viruses or to reduce the degree of immunosuppression, so that bacterial clearance can occur rapidly before microcolony formation and extensive lung damage occur . Once a large amount of bacterial replication and lung damage is present, the use of antibiotics is generally of limited value . A schematic illustration of the complexity of the various interactions and counteractions occurring during virus--bacterial synergistic interactions is presented in Fig . 1.

Bull Soc Pathol Exot Filiales, 1988, 81(4), 726 - 31
{A new sensitivity test for substances used as antiseptics or disinfectants . I . Biological studies}; Dodin A et al.; In this first article, the authors present a fast method of determining the bactericide and bacteriostatic power of the germs, based on the disparition of the succino-dehydrogenase activity of a bacterium, objectified by a neotetrazolium chloride reaction . This reaction allows a colorimetric qualitative and quantitative determination of the activity of a preparation and the duration of its contact with the bacteria . This method allows a study in electronic microscopy which will be published in a second article.

Zentralbl Bakteriol Mikrobiol Hyg {B}, 1988 Jan, 185(4-5), 350 - 67
{The use of UV rays for the disinfection of water . I . Microbiologic studies of drinking water}; Martiny H et al.; As a physical disinfection method without chemicals required the ultraviolet irradiation was tested for disinfection of drinking water . The survival was measured as a function of exposure to radiation for S . enteritidis, E . cloacae, C . freundii, S . marcescens, E . coli, K . pneumoniae und S . faecium . The bacteria were grown in trypton soya broth until they were well into the exponential phase . Two different UV-disinfection units were tested . Both consist of cylindrical shaped chambers with one low-pressure mercury-discharge lamp with their longitudinal axis parallel to the chambers . With 10(6) cfu/ml the experiments were done with three different rates of flow of 7,2 m3/h, 4,0 m3/h and 2,0 m3/h . The minimum exposures to radiation necessary to cause a 99.999% reduction were 10-86 mWs/cm2 depending on the test bacterium and on the UV-disinfection unit . The minimum doses ranged for S . enteritidis up to 13 mWs/cm2, for E . coli up to 21 mWs/cm2, for K . pneumoniae up to 39 mWs/cm2, for S . faecium up to 42 mWs/cm2, for E . cloacae up to 43 mWs/cm2, for C . freundii up to 72 mWs/cm2, and for S . marcescens up to 86 mWs/cm2.

Arch Biochem Biophys, 1988 Jan, 260(1), 134 - 8
Lysine and arginine transport in the photosynthetic bacterium Chromatium vinosum; Kim YA et al.; The photosynthetic purple sulfur bacterium Chromatium vinosum can take up both arginine and lysine in the light and, to a lesser extent, in the dark . Competitive inhibition experiments suggest the likely presence of two transport systems in this bacterium: One capable of transporting either lysine or arginine and a second capable of transporting arginine but not lysine . Uptake of both amino acids is electrogenic and appears to involve the cotransport of neither protons nor sodium ions . It is suggested that the transport occurs via an electrogenic uniport.

Cold Spring Harb Symp Quant Biol, 1988, 53 Pt 1, 11 - 7
Roles of methylation and phosphorylation in the bacterial sensing system; Koshland DE Jr et al.; Chemotaxis is an intriguing model system for the study of second-messenger pathways . One of the puzzles of second-messenger pathways in eukaryotic cells has been that many of these pathways interact, with one pathway either desensitizing or sensitizing an alternate messenger pathway . The chemotaxis system offered a particularly interesting chance to analyze such systems, because one of them is a methylation pathway and the other a phosphorylation pathway . The above description indicates that these two pathways interact with each other in a highly sophisticated way to produce an extremely important survival system . The stimulus on a receptor activates an excitation system that operates through phosphorylation, or the inhibition of phosphorylation, depending on whether the stimulus is a repellent or an attractant . That system ultimately generates or inhibits phosphorylation of a small peptide, the CheY protein, which apparently is the response regulator . The instant that this fast excitation is generated by a change in gradient, the change in conformation of the protein sets in motion a second process, i.e., the adaptation . That is a device which, over a longer period of time, has two functions: It serves as the comparator, which allows the comparison of the past with the present, essential for deletion of a gradient; it also sets in motion the reset to zero, so that the bacterium will not be overwhelmed by any one stimulus but can use all of its receptors to optimize its environment . These two systems by themselves are adequate for chemotaxis, but there is a further elegent complexity: The excitation system feeds back into the adaptation system to produce an asymmetry in the responses . The reason for that asymmetry is that the bacterium wishes to travel in the wrong direction only long enough to produce a detectable signal that it is migrating incorrectly . It wishes to keep swimming in the positive direction as long as the signals indicate that the direction is favorable . Hence, the feedback between the phosphorylation and methylation system involves further fine tuning.

Acta Otolaryngol Suppl, 1988, 454, 167 - 74
Bacterial adherence and upper respiratory tract disease: a correlation between S . pyogenes attachment and recurrent throat infections; Galioto GB et al.; The attachment of bacteria to mucosal surfaces is the initial event in the pathogenesis of infectious diseases . The authors present a study about the adherence of strain of S . pyogenes isolated in subjects with recurrent tonsillitis . A correlation was found between the adherence ability of the bacterium and the number of episodes per year . The study about the SIgA, the infection development and the bacterium adherence showed a direct correlation between SIgA levels and the number of phlogistic episodes . The importance of the role assumed by bacterial adherence in the genesis of the phlogistic process is to be emphasized yet again.

Adv Exp Med Biol, 1988, 239, 1 - 11
Lymphokine regulation of macrophage effector activities; Nacy CA et al.; Our concept of the regulation of macrophage activation is ever expanding and contracting . In regard to the number of LK that regulate macrophages killing activities, we have entered a new phase . In the beginning there was one macrophage activation factor, MIF; then there were many macrophage activation factors, most uncharacterized and bearing a variety of names . Then came IFN, a genetically cloned single reagent that induced destruction of virtually every target assessed; all activities of macrophages were assumed to be regulated by IFN . Once again, however, the LK universe is expanding: the number of single, cloned reagents that induce macrophage killing activities is amazing . With just two targets, a fibrosarcoma cell and an intracellular amastigote of L . major, we can identify 5 different macrophage activation factors, four of which are cloned and sequenced . As more recombinant reagents become available, the story of macrophage activation is likely to become even more complex . It is fascinating not only that certain of the LK are capable of inducing single effector reactions in the absence of effects on other effector activities, but also that at least one effector reaction requires the cooperation of several molecularly distinct LK . The complexity of LK activation factors that regulate a single effector reaction in vitro is compounded by the complexity in effector cell populations . For example, inflammatory macrophages exposed to LK kill the fibrosarcoma tumor target 5 to 10-fold better than an equal number of resident peritoneal macrophages . In contrast, LK treated resident macrophages eliminate intracellular amastigotes of leishmania far more efficiently than inflammatory cells . Thus, changes in cell populations dramatically affect the capacity to demonstrate a single effector reaction . Further, simple changes in assay conditions also determine whether an effector reaction can be observed in vitro . And superimposed upon all these layers of complexity is the target itself . The mechanisms a macrophages uses to block the replication of a virus may be totally ineffective in the destruction of a multicellular helminth, such as Schistosoma mansoni . And there is no reason to suspect that the extracellular destruction of a tumor target occurs by the same means that the macrophage uses to kill an intracytoplasmic bacterium, such as a rickettsia.(ABSTRACT TRUNCATED AT 400 WORDS)

Cell Motil Cytoskeleton, 1988, 11(1), 46 - 63
Characterization of gliding motility in Flexibacter polymorphus; Ridgway HF et al.; Motility of the marine gliding bacterium Flexibacter polymorphus was studied by using microcinematographic techniques . Following adhesion to a glass surface, multicellular filaments and individual cells usually began to glide within a few seconds at a speed of approximately 12 micron per second (at 23 degrees C) . Adhesion to the glass surface was evidently mediated by multitudes of extremely fine extracellular fibrils . Gliding velocity was independent of filament length but directly related to electron-transport activity and substratum temperature in the range 3-35 degrees C . The rate of gliding was inversely related to medium viscosity, suggesting that the locomotor apparatus functions at constant torque . Forward motion was occasionally interrupted by direction reversals, somersaults (observed primarily in single cells of short filaments), or spinning of filaments tethered by one pole . The frequency of direction reversal was found to be an inverse function of filament length . Translational motility was invariably accompanied by sinistral revolution about the longitudinal axis of a filament . The sense and pitch of revolution were constant among filaments of different length . Polystyrene microspheres or India ink particles adsorbed to gliding cells were actively displaced in either direction, their movement tracing either a regular zigzag or helical path along the filament surface . Because microspheres were also observed to move on nonmotile filaments, particle translocation was evidently not obligatorily linked to gliding locomotion . Multiple particles adsorbed to a single filament often moved independently . The data are consistent with a motility mechanism involving limited motion in numerous mechanically independent (yet functionally coordinated) domains on the cell surface.

Proteins, 1988, 4(1), 63 - 70
Model of a complex between the tetrahemic cytochrome c3 and the ferredoxin I from Desulfovibrio desulfuricans (Norway strain); Cambillau C et al.; A three-dimensional model of an electron-transfer complex between the tetrahemic cytochrome c3 and the ferredoxin I from the sulfate-reducing bacterium Desulfovibrio desulfuricans (Norway strain) has been generated through computer graphics methods . The model is based on the known X-ray structure of the cytochrome and on a model of the ferredoxin that has been derived through computer graphics modeling and energy minimization methods, from the X-ray structure of the homologous ferredoxin from Peptococcus aerogenes . Four possible models of interaction between the two molecules were examined by bringing in close proximity each of the four hemes and the redox center (4Fe-4S) of the ferredoxin and by optimizing the ion pairs interactions . One of these models shows by far the "best" structure in terms of charges, interactions, and complementarity of the topology of the contact surfaces . In this complex, the distance between the iron atoms of the ferredoxin redox center and the hemic iron atom is 11.8 A, which compares well with those found between redox centers in other complexes . The contact surface area between the two molecules is 170 A2.

Virchows Arch A Pathol Anat Histopathol, 1988, 412(6), 563 - 72
Cat scratch disease . An epidemiological and ultrastructural study of lymphadenitis caused by Warthin-Starry positive bacteria; Kudo E et al.; The aetiological agent of cat scratch disease (CSD) has been unknown for more than 30 years . Recently, a micro-organism clearly shown with Warthin-Starry silver (W-S) stain was found and thought to be a possible cause of the disease . In this study, 32 cases of regional lymphadenopathy histologically compatible with CSD and 20 contrasting cases of lymphadenopathy were examined retrospectively with W-S stain . W-S positive pleomorphic organisms were clearly demonstrated in 20 of the 32 suspected cases of CSD, but in none of the other cases . The onset of disease in these 20 cases with W-S positive organisms occurred between July and January . This seasonal variation in the onset of disease was highly significant (P less than 0.005) and was not due to a single epidemic . Moreover, some characteristic morphological features of the organism were found by electron microscopic observations . Ultrastructurally, the organism was a bacterium showing a chain-like arrangement, septal formation, branching and clubbed ends.

J Immunol, 1987 Dec 15, 139(12), 4203 - 7
Lysis of cells infected with typhus group rickettsiae by a human cytotoxic T cell clone; Carl M et al.; Cytolytic human T cell clones generated in response to the intracellular bacterium Rickettsia typhi were characterized . Growing clones were tested for their ability to proliferate specifically in response to antigens derived from typhus group rickettsiae or to lyse targets infected with R . typhi or Rickettsia prowazekii . Two clones were able to lyse targets infected with typhus group rickettsiae . One of these clones was more fully characterized because of its rapid growth characteristics . This cytolytic clone was capable of lysing an autologous infected target as well as a target matched for class I and II histocompatibility leukocyte antigens (HLA) . It was not capable, however, of lysing either a target mismatched for both class I and II HLA or a target partially matched for class I HLA . In addition, the clone exhibited specificity in that it was able to lyse an autologous target infected with typhus group rickettsiae, but did not lyse an autologous target infected with an antigenically distinct rickettsial species, Rickettsia tsutsugamushi . These results demonstrate, for the first time, that cells infected with intracellular bacteria can be lysed by human cytotoxic T lymphocytes.

Biochim Biophys Acta, 1987 Dec 14, 922(3), 287 - 93
Inhibition of acetoacetyl-CoA synthetase from rat liver by fatty acyl-CoAs; Ito M et al.; The activity of acetoacetyl-CoA synthetase from rat liver was found to be negatively regulated by coenzyme A, fatty acyl-CoAs and acetoacetyl-CoA in vitro . With increasing concentrations of coenzyme A (substrate inhibition occurring at concentrations higher than 50 microM) the pH optimum shifted toward the acidic side (7.5-8.5 with 5 microM coenzyme A and 6.5-7.0 with 500 microM coenzyme A), in parallel with progressively decreasing enzyme activity . Fatty acyl-CoAs of various chain lengths dose-dependently inhibited acetoacetyl-CoA synthetase from rat liver, but much less effectively a similar enzyme from a bacterium, Zoogloea ramigera I-16-M . Palmitoyl-CoA, the most potent inhibitor of the rat liver enzyme, with an apparent Ki value of 9.8 microM, apparently inhibited the enzyme below its critical micellar concentration, not due to its detergent action . Acetoacetyl-CoA showed product inhibition with a Ki value of 15 microM . These results suggest a possible physiological regulation mechanism for this enzyme with respect to fatty acid biosynthesis.

J Bacteriol, 1987 Dec, 169(12), 5801 - 7
Involvement of transport in Rhodobacter sphaeroides chemotaxis; Ingham CJ et al.; The chemotactic response to a range of chemicals was investigated in the photosynthetic bacterium Rhodobacter sphaeroides, an organism known to lack conventional methyl-accepting sensory transduction proteins . Strong attractants included monocarboxylic acids and monovalent cations . Results suggest that the chemotactic response required the uptake of the chemoeffector, but not its metabolism . If a chemoeffector could block the uptake of another attractant, it also inhibited chemotaxis to that attractant . Sodium benzoate was not an attractant but was a competitive inhibitor of the propionate uptake system . Binding in an active uptake system was therefore insufficient to cause a chemotactic response . At different concentrations, benzoate either blocked propionate chemotaxis or reduced the sensitivity of propionate chemotaxis, an effect consistent with its role as a competitive inhibitor of uptake . Bacteria only showed chemotaxis to ammonium when grown under ammonia-limited conditions, which derepressed the ammonium transport system . Both chemotaxis and uptake were sensitive to the proton ionophore carbonyl cyanide m-chlorophenylhydrazone, suggesting an involvement of the proton motive force in chemotaxis, at least at the level of transport . There was no evidence for internal pH as a sensory signal . These results suggest a requirement for the uptake of attractants in chemotactic sensing in R . sphaeroides.

Acta Pathol Jpn, 1987 Dec, 37(12), 1973 - 7
Nonspecific simple eosinophilic granulomatous prostatitis with eosinophilia in peripheral blood . A case report; Sugiura H et al.; Nonspecific simple eosinophilic granulomatous prostatitis is extremely rare and in the present paper, the first case showing eosinophilia in the peripheral blood is reported . The patient was a 55-year-old Japanese man who was admitted because of difficulty in urination over a period of several years . The laboratory findings revealed marked eosinophilia (36%) in the peripheral blood, but the patient's past history showed neither bronchial asthma nor any allergic tendency . Transurethral resection of the prostate was performed and the histopathologic findings revealed a picture of non-caseating granulomatous prostatitis with massive eosinophilic infiltration without fibrinoid necrosis or vasculitis . Fragments of the prostatic urethra also showed the same findings . No fungus, bacterium or parasite was found . Although remnants of smooth muscle fibers were noted in the granulomas, neither immunoglobulins nor complement components could be demonstrated, and the etiology remained undetermined.

J Bacteriol, 1987 Dec, 169(12), 5808 - 14
Methylation-independent and methylation-dependent chemotaxis in Rhodobacter sphaeroides and Rhodospirillum rubrum; Sockett RE et al.; In vivo and in vitro methylation, methanol production assays, and the use of specific antibodies raised against the sensory transducing protein Tar in Escherichia coli all failed to demonstrate the presence of methyl-accepting chemotaxis proteins (MCPs) in the photosynthetic bacterium Rhodobacter sphaeroides, although such proteins did exist in another photosynthetic bacterium, Rhodospirillum rubrum . The range of chemicals to which Rhodobacter sphaeroides responds, the lack of an all-or-none response, and the lack of true repellents indicate an alternative chemosensory pathway . The existence of MCPs in Rhodospirillum rubrum means that the lack of MCPs is not the result of a phototrophic metabolism, but may be connected to the unidirectional flagellar motor of Rhodobacter sphaeroides.

J Bacteriol, 1987 Dec, 169(12), 5575 - 8
Actinomycin synthesis in Streptomyces antibioticus: enzymatic conversion of 3-hydroxyanthranilic acid to 4-methyl-3-hydroxyanthranilic acid; Jones GH; A methyltransferase which utilizes 3-hydroxyanthranilic acid (HAA) as a substrate was identified in detergent-treated extracts of the bacterium Streptomyces antibioticus . The enzyme catalyzes the transfer of methyl groups from {14C}S-adenosylmethionine to HAA, but does not catalyze the methylation of 3-hydroxy-DL-kynurenine . Enzyme, substrate, time, and pH dependencies for the methyl transfer reaction were examined . Reaction products obtained from scaled-up reaction mixtures were fractionated by chromatography on Dowex 1, and the Dowex 1 fractions were examined by paper and thin-layer chromatography . One Dowex fraction was shown to contain a radioactive product with the chromatographic properties of 4-methyl-3-hydroxyanthranilic acid (MHA), a known intermediate in the biosynthesis of actinomycin . Available evidence indicates that the conversion of HAA to MHA is an early step in the biosynthesis of actinomycin by S . antibioticus and other actinomycin-producing streptomycetes.

Eur J Biochem, 1987 Nov 16, 169(1), 167 - 73
The occurrence of 2'-5' oligoadenylates in Escherichia coli; Trujillo MA et al.; The use of a highly specific radioimmunoassay and of HPLC permitted us to confirm the occurrence of 2'-5' oligoadenylates {p chi (A2'p5')nA} in several strains of Escherichia coli . Cellular concentrations of 2'-5' oligoadenylates ranged from 50 nM to 300 nM . The mixture of 2'-5' oligoadenylates consisted primarily of pppA2'p5'A, pA2'p5'A,A2'p5'Ap and A2'p5'A under normal conditions of growth . None of them activated RNase L . Infection of the bacteria with the single-stranded DNA phage M13 or induction of a heat-inducible, non-lytic mutant of phage lambda led to a significant increase in the total pool of 2'-5' oligoadenylates, paralleling the progressive inhibition of growth . Likewise, the inhibition of protein synthesis with chloramphenicol stimulated the accumulation of 2'-5' oligoadenylates . Furthermore, the inhibition of bacterial growth by either phage or by chloramphenicol brought about a change in the composition of the 2'-5' oligoadenylate pool; 5'-phosphorylated 2'-5' oligoadenylates accumulated and became the major components . The findings indicate a parallelism between the effects of viral infection on the synthesis of 2'-5' oligoadenylates in eukaryotes and similar effects subsequent to phage growth in the bacterium E . coli.

J Biol Chem, 1987 Nov 5, 262(31), 14983 - 9
Respiratory enzymes of Thiobacillus ferrooxidans . A kinetic study of electron transfer between iron and rusticyanin in sulfate media; Blake RC 2nd et al.; Thiobacillus ferrooxidans is a chemolithotrophic bacterium capable of fulfilling all of its energy requirements from the oxidation of soluble ferrous sulfate . Rusticyanin is a soluble blue copper protein found in abundance in the periplasmic space of this bacterium . The one-electron transfer reaction between soluble iron and purified rusticyanin has been studied by stopped flow spectrophotometry in acidic solutions containing sulfate . Second order rate constants for the reduction of rusticyanin by Fe2+, FeHSO4+, and FeSO4(0) were 0.022, 0.73, and 2.30 M-1 s-1, respectively . The pseudo-first order rate constant for the reduction of rusticyanin exhibited substrate saturation when the concentration of the total ferrous ion was varied in solutions of limiting sulfate . This saturation behavior was quantitatively described using the values of the second order rate constants listed above and the distribution of the total ferrous ion into its water-, bisulfate-, and sulfate-coordinated forms . Second order rate constants for the oxidation of rusticyanin by Fe3+ and FeSO4+ were 0.73 and 0.26 M-1 s-1, respectively . The electron transfer reactions between iron and rusticyanin monitored in vitro were far too slow to support the hypothesis that rusticyanin is the primary oxidant of ferrous ions in the iron-dependent respiratory electron transport chain of T . ferrooxidans.

J Bacteriol, 1987 Nov, 169(11), 5279 - 88
Protein inclusions produced by the entomopathogenic bacterium Xenorhabdus nematophilus subsp . nematophilus; Couche GA et al.; The entomopathogenic bacterium Xenorhabdus nematophilus subsp . nematophilus produces two types of intracellular inclusion bodies during in vitro culture . Large cigar-shaped inclusions (designated type 1) and smaller ovoid inclusions (designated type 2) were purified from cell lysates, using differential centrifugation in discontinuous glycerol gradients and isopycnic density gradient centrifugation in sodium diatrizoate . The inclusions, composed almost exclusively of protein, are readily soluble at high and low pH values and in the presence of cation chelators such as EDTA, anionic detergents (sodium dodecyl sulfate), or protein denaturants (urea, NaBr) . Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of purified inclusions revealed a single 26-kilodalton protein (IP-1) in type 1 inclusions and a 22-kilodalton protein (IP-2) in type 2 inclusions . Analysis of these proteins by isoelectric focusing in the presence of 8 M urea showed that IP-1 is acidic and IP-2 is neutral . Furthermore, each protein occurred in multiple forms differing slightly in isoelectric point . Other variations in peptides released by trypsin digestion, immunological properties, and amino acid composition revealed significant structural differences between IP-1 and IP-2 . Kinetic studies using light microscopy, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and immunoblotting procedures showed that inclusion protein synthesis occurs only during the second half of exponential culture growth . Synthesis of inclusion proteins and their aggregation to form inclusions occurred concurrently . Possible functions for these abundant proteins are discussed.

Infect Immun, 1987 Nov, 55(11), 2701 - 5
Influence of growth temperature on virulence of Legionella pneumophila; Edelstein PH et al.; The effect of growth temperature on the virulence of a strain of broth-grown serogroup 1 Legionella pneumophila (Wadsworth F889) was examined by growing the bacterium at different temperatures and then infecting guinea pigs (by intratracheal injection) and guinea pig alveolar macrophages . The 50% lethal dose for guinea pigs infected with 25 degrees C-grown F889 was log10 5.0 CFU and that for 41 degrees C-grown F889 was log10 5.7 CFU, or a fivefold difference . Guinea pig alveolar macrophages were infected in quadruplicate with log10 3.8 CFU of F889 cells grown at either 25 or 41 degrees C . Counts of F889 in the alveolar macrophages infected with 25 degrees C-grown bacteria were 40% greater after 1 day of incubation (P = 2 X 10(-4)) than were counts in the alveolar macrophage suspensions inoculated with 41 degrees C-grown bacteria . However, the counts were not significantly different after 3 days of incubation . Examination of cover slip cultures of guinea pig alveolar macrophages infected with 25 degrees C-grown or 41 degrees C-grown bacteria showed that the bacteria grown at the lower temperature were twice as likely to be macrophage-associated after 1 h of incubation than were the bacteria grown at the higher temperature . Growth at the lower temperature was also associated with a change in reactivity with monoclonal antibodies, but not with a change in plasmid content . Thus, environmental temperature may play an important role in modulating the virulence of L . pneumophila, possibly by affecting bacterial adherence to host cells.

EMBO J, 1987 Nov, 6(11), 3515 - 20
Biological consequences of segmental alterations in mRNA stability: effects of deletion of the intercistronic hairpin loop region of the Rhodobacter capsulatus puf operon; Klug G et al.; It has been proposed that intercistronic stem and loop structures located in the puf operon of the photosynthetic bacterium Rhodobacter capsulatus account for segmental differences in transcript stability and consequently, the differential expression of the B870 and reaction center (RC) proteins encoded by puf . We report here that deletion of these structures leads to a failure to detect as discrete fragments the B870-encoding 0.49 kb and 0.50 kb mRNA segments located upstream from the site of the hairpins . The absence of these stable transcript fragments is associated with altered stoichiometry of the B870 and RC pigment-protein complexes in the bacterial intracytoplasmic membrane and a decreased rate of cell growth under photosynthetic conditions . These results support the view that the hairpin loop structures of the puf intercistronic region function in vivo to impede exoribonucleolytic degradation of upstream mRNA and establish that segmental variations in mRNA stability have a biologically important role in regulating the expression of puf operon genes.

J Exp Med, 1987 Nov 1, 166(5), 1377 - 89
Phagocytosis of Legionella pneumophila is mediated by human monocyte complement receptors; Payne NR et al.; We have examined receptors mediating phagocytosis of the intracellular bacterial pathogen, Legionella pneumophila . Three mAbs against the type 3 complement receptor (CR3), which recognizes C3bi, inhibit adherence of L . pneumophila to monocytes by 64 +/- 8% to 74 +/- 11% . An mAb against the type 1 complement receptor (CR1), which recognizes C3b, inhibits adherence by 68 +/- 1% . mAbs against other monocyte surface antigens do not significantly influence adherence . Monocytes plated on substrates of L . pneumophila membranes modulate their CR1 and CR3 receptors but not Fc receptors; such monocytes bind 70% fewer C3b-coated erythrocytes and 53% fewer C3bi-coated erythrocytes than control monocytes . Adherence of L . pneumophila to monocytes in nonimmune sera is dependent on heat-labile serum opsonins; adherence is markedly reduced in heat-inactivated serum (84% reduction) or buffer alone (97% reduction) compared with fresh serum . mAbs against CR1 and CR3 receptors also inhibit L . pneumophila intracellular multiplication and protect monocyte monolayers from destruction by this bacterium . This study demonstrates that human monocyte complement receptors, CR1 and CR3, mediate phagocytosis of L . pneumophila . These receptors may play a general role in mediating phagocytosis of intracellular pathogens.

Microbiol Sci, 1987 Nov, 4(11), 338 - 41
Temporal and spatial regulation of differentiation in Caulobacter crescentus; Newton A; Asymmetric cell division in the aquatic bacterium C . crescentus has proved to be a fruitful model for the study of cell differentiation . An understanding of the temporal and spatial mechanisms responsible for complex developmental programmes leading to polar morphogenesis is possible in these cells using a combination of genetic, biochemical, and molecular approaches.

Biochemistry, 1987 Oct 6, 26(20), 6521 - 6
Purification and partial characterization of the membrane-bound cytochrome o(561,564) from Vitreoscilla; Georgiou CD et al.; Cytochrome o(561,564) terminal oxidase was solubilized from the membrane fraction of the bacterium Vitreoscilla sp., strain C1, and purified by differential pH dialysis, gel filtration chromatography, and ion-exchange chromatography . Subunit molecular weights, determined on sodium dodecyl sulfate-polyacrylamide gels by the Ferguson plot method, were 49,500 and 23,500 . There were two protohemes IX, two coppers, and 45 mol of phosphorus per mole of protomer (73,000) . The molecular weight of the cytochrome o complex estimated by chromatography on Sephacryl-400 in deoxycholate was 265,000, which is consistent with the enzyme complex under these conditions being a dimer (146,000) with the remaining molecular weight contribution arising from bound phospholipid, deoxycholate, and possibly other, smaller subunits . Difference spectra of the dithionite-reduced enzyme have split alpha absorption maxima at 561 and 564 nm at room temperature and 558 and 561 nm at 77 K . The CO difference spectrum at room temperature has absorption maxima at 570, 534, and 416 nm . Dissociation constants for CO and cyanide binding to the reduced and oxidized forms of the oxidase are 5.2 microM and 3.5 mM, respectively . The hemes in the cytochrome are one electron accepting centers, both with midpoint potentials around +165 mV at pH 7.0 . The enzyme is highly autoxidizable, and its menadiol oxidizing activity is stimulated by phospholipids.

Int J Radiat Biol Relat Stud Phys Chem Med, 1987 Oct, 52(4), 603 - 13
Major E . coli heat-stress protein do not translocate: implications for cell survival; Yatvin MB et al.; When Escherichia coli are exposed to heat stress, the majority of proteins in the process of synthesis at the time of heat stress are rapidly translocated to the outer membrane of the bacterium . The synthesis of most of these proteins appears to take place on membrane-bound polyribosomes . With the temperature shift, overall protein synthesis is inhibited while the synthesis of a small group of proteins is initiated . These proteins are not translocated, but remain in the cytosolic compartment, and they are identifiable as heat-stress proteins . Both the translocation phenomenon and the retention of heat-stress proteins in the cytosolic compartment in proximity to the nucleoid could counteract the effects of heat stress . The translocated proteins may operate by stabilizing the outer membrane prior to the induction of heat-stress proteins and the latter, which are confined to the cytoplasmic compartment, may serve to protect the integrity of the nucleoid structures.

J Cell Biol, 1987 Oct, 105(4), 1821 - 8
Localizing the subunit pool for the temporally regulated polar pili of Caulobacter crescentus; Smit J; The pili of the stalked bacterium Caulobacter crescentus are assembled at a specific time in the life cycle at one pole of the cell and are composed of the monomer protein, pilin . A previous study demonstrated that the onset of pilin synthesis occurs well before pili appear on the surface, suggesting that pilin accumulates within the cell . In the present study, an electron microscope immunocytochemistry assay was used to determine the subcellular location of this unassembled pilin and its fate during pilus assembly and cell division . Populations of synchronously growing cells were embedded in epoxy resin at selected times during the cell cycle . Ultrathin sections were treated with pilin-specific antibody, followed by protein A coupled to colloidal gold . It was determined that the cellular location for unassembled pilin was the cell cytoplasm . All cell membranes and regions of nuclear material were poorly labeled . Quantitation demonstrated that label density increased during the period of pilin synthesis and declined during the period of pilus assembly and maintenance . The pilin pool was not unequally segregated at division; e.g., to the daughter cell that is elaborating pili . Mutants which have simultaneously lost the ability to produce flagella, pili, and other polar organelles, possibly due to alterations in the specialized region of polar organelle assembly, were also examined by the immunocytochemistry technique . There was no significant difference in the pilin pool size relative to the wild type, indicating that pilin synthesis continues in the absence of a functioning assembly site . This pattern of synthesis and assembly for the pilus is significantly different from that of the polar flagellum which is produced at the same time and location on the cell surface . These findings are discussed in relation to the hypothesized organization center at the cell pole which may have a major role in directing the assembly of all the polar structures.

Biochim Biophys Acta, 1987 Sep 25, 921(2), 275 - 80
Enzymes involved in the formation of 3 beta, 7 beta-dihydroxy-12-oxo-5 beta-cholanic acid from dehydrocholic acid by Ruminococcus sp . obtained from human intestine; Akao T et al.; Ruminococcus sp . PO1-3 from human intestinal flora reduced dehydrocholic acid to 3 beta-hydroxy-7,12-dioxo-5 beta-cholanic acid by means of the enzyme 3 beta-hydroxysteroid dehydrogenase (Akao, T., Akao, T., Hattori, M., Namba, T . and Kobashi, K . (1986) J . Biochem . (Tokyo) 99, 1425-1431) . This bacterium and its crude extract gave rise to another product, showing a lower RF value on TLC, from dehydrocholic acid . The product was identified as 3 beta, 7 beta-dihydroxy-12-oxo-5 beta-cholanic acid . The crude extract reduced 7-ketolithocholic acid and its methyl ester, but not 6-ketolithocholic acid and 12-ketochenodeoxycholic acid, in the presence of NADPH, and oxidized ursodeoxycholic acid and beta-muricholic acid, but not cholic acid, chenodeoxycholic acid, deoxycholic acid and hydrocholic acid, in the presence of NADP+ . Therefore, besides 3 beta-hydroxysteroid dehydrogenase, 7 beta-hydroxysteroid dehydrogenase was shown to be present in this bacterium . The two dehydrogenases were clearly separated from each other by butyl-Toyopearl 650 M column chromatography . From dehydrocholic acid, 7 beta-hydroxy-3,12-dioxo-5 beta-cholanic acid was produced by 7 beta-hydroxysteroid dehydrogenase and 3 beta, 7 beta-dihydroxy-12-oxo-5 beta-cholanic acid was produced by combination of two enzymes, 7 beta- and 3 beta-hydroxysteroid dehydrogenase.

FEBS Lett, 1987 Sep 14, 221(2), 299 - 304
Phenylhydrazine as probe for cofactor identification in amine oxidoreductases . Evidence for PQQ as the cofactor in methylamine dehydrogenase; van der Meer RA et al.; Homogeneous methylamine dehydrogenase (primary-amine:(acceptor) oxidoreductase (deaminating), EC 1.4.99.3, MADH) from the bacterium Thiobacillus versutus was treated with the inhibitor phenylhydrazine (PH) . Derivatization of the cofactor in MADH took place in a fast reaction to give compound I . A different product, compound II, was formed in a slow reaction at high O2 concentrations . The compounds I and II could be removed from the protein by proteolysis with pronase and purified to homogeneity . Products showing identical absorption spectra and chromatographic behaviour were isolated from the reaction mixture after incubating pyrroloquinoline quinone (PQQ) with PH . Upon dissolving in dimethyl sulphoxide, both the enzyme-derived as well as the model-system-derived compounds I and II were nearly quantitatively transformed into PQQ . The conclusion is, therefore, that MADH from T . versutus contains covalently bound PQQ, removable from the protein with pronase, and not a structural analogue of this cofactor without the carboxylic acid groups, as was recently proposed for MADH from Bacterium W3A1 {(1986) Biochem . Biophys . Res . Commun . 141, 562-568} . The properties of compounds I and II suggest that they are the 'azo adduct' and the 'hydrazone adduct' of PH and PQQ at the C(5)-position, respectively . The finding that the reaction of a hydrazine with PQQ can lead to two different products, in enzymes as well as in a model system, has important implications for the interpretation of recent comparative studies aimed at detection of PQQ in amine oxidoreductases with Raman spectroscopy.

J Biol Chem, 1987 Sep 5, 262(25), 12096 - 103
Non-adenylylated bis(5'-nucleosidyl) tetraphosphates occur in Saccharomyces cerevisiae and in Escherichia coli and accumulate upon temperature shift or exposure to cadmium; Coste H et al.; A new set of bis(5'-nucleosidyl) tetraphosphates, the Bp4B' nucleotides (B and B' = C, G, or U not equal to A), are demonstrated in living cells . In exponentially growing Saccharomyces cerevisiae, cellular concentrations of Cp4U, Up4U, Gp4G, Cp4C, Gp4U, and Gp4C are 210, 200, 60, 50, 40, and 30 nM, respectively . It is likely that these nucleotides originate from the action of diadenosine-5',5"'-P1,P4-tetraphosphate alpha,beta-phosphorylase, an enzyme recently found in yeast . Upon temperature shift or exposure to cadmium, the Bp4B' nucleotides strongly accumulate in the yeast cells . In Escherichia coli, the same nucleotides occur, and similar effects of temperature shift or of cadmium are observed . However, in the bacterium, the origin of these nucleotides is not known . To quantitate these nucleotides in cellular extracts, specific procedures were developed . In the first step, after purification of the mixture of Np4N' (N and N' = A, C, G, or U) nucleotides, the Ap4N nucleotides are specifically removed by incubation with lysyl-tRNA synthetase . In the second step, the Bp4B' species are resolved with the help of anion-exchange high performance liquid chromatography . In the third step, the concentration of each Bp4B' is measured using three coupled enzymatic reactions to produce ATP and bioluminescence . With this strategy, 0.01 pmol of any Bp4B' nucleotide can be reliably detected.

Infect Dis Clin North Am, 1987 Sep, 1(3), 595 - 614
Legionella infections; Ching WT et al.; Legionnaires' disease is a distinct clinical entity caused by Legionella pneumophila . Following an epidemic of pneumonia in Philadelphia in 1976, it was found that the bacterium had in fact been first isolated in 1947 . Other species of Legionella have been identified, many of which are indistinguishable from L . pneumophila infection . Legionella species also cause extrapulmonary infections and a mild nonpneumonic form of disease known in its epidemic form as Pontiac Fever.

Urologe A, 1987 Sep, 26(5), 256 - 62
{Genital chlamydia infections--clinical aspects, diagnosis and therapy}; Korting HC et al.; Non-gonococcal urethritis and its counterpart in women have become the most frequent genital infection worldwide . As Chlamydia trachomatis is the major causative agent interest has focused on this bacterium . While genital chlamydial infection in men often is manifest the opposite holds true for women . Major complications such as pelvic inflammatory disease can nevertheless turn up . Therefore efficient diagnostic tools are badly needed . If tissue culture procedures are not available direct specimen tests can be performed using fluorescence labelled monoclonal antibodies . For therapy tetracyclines and erythromycin are still the drugs of choice although the cure rates are not totally acceptable . Therefore evaluation of the new quinolones deserves interest.

Genetika, 1987 Sep, 23(9), 1708 - 10
{Inhibition of colicin synthesis during integration of transposons into the ColE1 plasmid in Escherichia coli}; Krashennikova LV; Insertions of transposons into ColE1 plasmid have been shown to influence the plasmid-specified colicin synthesis . The quantity of colicin produced by a single bacterium being unchanged, a portion of colicin-producing cells in the population of those containing insertion mutants was 10(1)-10(4)-fold lower than in the case of ColE1 . The effect of transposon was only observed in cis . Insertions were located in different sites of plasmid in both orientations . No secondary DNA rearrangements were formed in regions adjacent to the points of insertions . On the basis of data obtained . It is concluded that the phenomenon can be connected with neither of known types of mutations induced by transposons . A possibility of existence of a new type of such mutations is discussed.

J Biol Chem, 1987 Aug 15, 262(23), 11012 - 9
Steady-state kinetic analysis for the reaction of ammonium and alkylammonium ions with methylamine dehydrogenase from bacterium W3A1; McIntire WS; The steady-state kinetic mechanism for the reaction of n-alkylamines and phenazine ethosulfate (PES) or phenazine methosulfate (PMS) with methylamine dehydrogenase from bacterium W3A1 is found to be of the ping-pong type . This conclusion is based on the observations that 1/v versus 1/{methylamine} or 1/{butylamine} plots, at various constant concentrations of an oxidizing substrate, and 1/v versus 1/{PES} or 1/{PMS} plots, at various constant concentrations of a reducing substrate, are parallel . Additionally, the values of kcat/Km for four n-alkylamines are identical when PES is the oxidizing substrate, as were the kcat/Km values for four reoxidizing substrates when methylamine was the reducing substrate . Last, analysis of steady-state kinetic data obtained when methylamine and propylamine are presented to the enzyme simultaneously and PES and PMS are used simultaneously also supports the involvement of a ping-pong mechanism . The enzymic reaction with either methylamine or PES is dependent on the ionic strength, and the data indicate that each interacts with an anionic site on methylamine dehydrogenase . The presence of ammonium ion at low concentration activates the enzyme, but at high concentration this ion is a competitive inhibitor in the reaction involving methylamine and the enzyme . A complete steady-state mechanism describing these ammonia effects is presented and is discussed in light of the nature of the pyrroloquinoline quinone cofactor covalently bound to the enzyme.

Zentralbl Bakteriol Mikrobiol Hyg {A}, 1987 Aug, 266(1-2), 116 - 26
Interaction of Escherichia coli and macrophages: alteration by treatment of bacteria with beta-lactam antibiotics; Opferkuch W et al.; Antibiotics are known to exert an influence on the host-parasite relationship either by impairment of immunocompetent cells or by alteration of the bacterium, such as changes of surface properties or the production of toxins . The main problem in investigating the effect of antibiotics on the surface properties of bacteria consists in morphological changes of bacteria (round cell or filament formation) after treatment e.g . with beta-lactam antibiotics . These changes of morphology lead to problems in the comparison of such bacterial forms with untreated organisms . Therefore, in this study outer membrane vesicles from bacteria were used as a model to investigate the effect of antibiotics on the surface properties of Escherichia coli with regard to the interaction with mouse peritoneal macrophages tested by chemiluminescence reaction . It could be shown that these membrane vesicles induce a luminol dependent chemiluminescence response . Treatment of E . coli with different beta-lactams lead to an increase of the stimulating properties . The relative effectiveness of certain antibiotics depended on the particular E . coli strain . Analysis of the different adhesions involved in the stimulation of macrophages revealed that only mannose-sensitive adhesins were increased after treatment with beta-lactam antibiotics . No stimulation of the membrane-bound NAD(P)H-oxidase could be found following the reaction with outer membrane vesicles . Even the treatment of bacteria with antibiotics did not evoke such a reaction.

J Periodontol, 1987 Aug, 58(8), 540 - 5
Tissue localization of Actinobacillus actinomycetemcomitans in human periodontitis . II . Correlation between immunofluorescence and culture techniques; Christersson LA et al.; Recent immunohistological studies have suggested that Actinobacillus actinomycetemcomitans is present in the gingival tissues in juvenile periodontitis lesions . The present study examined tissue bound A . actinomycetemcomitans by bacterial culture and immunohistological demonstration of antigen in tissue . A total of 14 periodontitis lesions were examined . Eleven biopsies were obtained from gingiva adjacent to A . actinomycetemcomitans infected pockets, while the remaining three control biopsies were obtained from gingiva adjacent to pockets where subgingival A . actinomycetemcomitans infection could not be detected . Each biopsy was hemisected, one half was used for immunofluorescence microscopic examination while the other half was processed for culture of A . actinomycetemcomitans . The latter section was surface-disinfected, repeatedly washed and then minced to release bacteria from within the tissues . Aliquots from the serial washings and the minced tissue suspension were cultured on medium selective for A . actinomycetemcomitans . Surface disinfection and serial washings gradually decreased cultivable A . actinomycetemcomitans in the washings aliquots . Following tissue disruption, an increase in colony-forming units of A . actinomycetemcomitans was seen from eight of the 11 test biopsies . This bacterium could not be detected in washings or minced tissue suspensions from the control biopsies obtained from lesions in which subgingival A . actinomycetemcomitans was previously not detected . A positive correlation was seen between the presence of A . actinomycetemcomitans antigens in the gingival biopsies and; (1) A . actinomycetemcomitans colony-forming units released from the minced tissues (r = 0.90, p = 0.000), as well as; (2) the colony-forming units from the periodontal pocket (r = 0.62, P = 0.017).(ABSTRACT TRUNCATED AT 250 WORDS)

Zentralbl Bakteriol Mikrobiol Hyg {B}, 1987 Aug, 184(6), 495 - 500
{Multiplication and killing temperatures of naturally occurring legionellas}; Schulze-Robbecke R et al.; Suspensions of legionellae and associated bacteria found in a hot water distribution system were maintained in the exponential phase of growth without addition of nutrients by constant agitation and oxygenation and by periodically transferring them to autoclaved tap water . The suspensions were exposed to different temperatures to determine growth and inactivation kinetics of legionellae kept under conditions similar to their natural environment . Multiplication of the legionellae was found to occur in a temperature range between 20 and 43 degrees C and inactivation was observed above 50 degrees C . Decimal reduction times decreased with increasing temperatures . These findings do not support the hypothesis that naturally occurring legionellae are more heat resistant than strains of the bacterium cultured on artificial media . Frequent failure to eradicate legionellae from hot water systems by elevating the water temperature indicates that it is impossible to achieve effective temperature levels concomitantly in all parts of the system.

J Bacteriol, 1987 Aug, 169(8), 3801 - 8
Cloning of the gene for myxobacterial hemagglutinin and isolation and analysis of structural gene mutations; Romeo JM et al.; Myxobacterial hemagglutinin (MBHA) is a major developmentally induced protein that accumulates during the period of cellular aggregation in the bacterium Myxococcus xanthus . It has been shown that this lectin is targeted to the cell surface and periplasmic space of developmental cells, suggesting that it may play a role in cell-cell recognition or agglutination . We have cloned the structural gene for MBHA by using synthetic deoxyoligonucleotides containing sequences deduced from the amino acid sequence of MBHA and have used the cloned gene to construct strains of M . xanthus that cannot synthesize MBHA . We found that although the MBHA-deficient strains are delayed in their developmental time course, they are otherwise able to aggregate and sporulate normally . Our results suggest that MBHA may function to increase the efficiency of fruiting-body formation but is not a critical component of cellular aggregation.

J Bacteriol, 1987 Aug, 169(8), 3669 - 78
Cloning of the gene for phosphoribulokinase activity from Rhodobacter sphaeroides and its expression in Escherichia coli; Hallenbeck PL et al.; A 3.4-kilobase EcoRI restriction endonuclease fragment has been cloned from the facultatively photoheterotrophic bacterium Rhodobacter sphaeroides and shown to contain the structural gene (prkA) for phosphoribulokinase (PRK) activity . The PRK activity was characterized in Escherichia coli, and the product of the reaction was identified . The prkA gene was localized to a 1,565-base-pair EcoRI-PstI restriction endonuclease fragment and gave rise to a 33-kilodalton polypeptide both in vivo and in vitro . The gene product produced in E . coli was shown to be identical to the gene product produced in R . sphaeroides . The amino acid sequence for the amino-terminal region deduced from the DNA sequence confirmed that derived for partially purified PRK derived from both E . coli and R . sphaeroides . In addition, the 3.4-kilobase EcoRI restriction endonuclease fragment coded for a 37-kilodalton polypeptide of unknown function, and preliminary evidence indicates that this DNA fragment is linked to genes coding for other activities significant in photosynthetic carbon assimilation . The genetic organization and proposed operon structure of this DNA fragment are discussed.

J Immunol, 1987 Jul 15, 139(2), 551 - 6
Cytolytic activity of human peripheral blood leukocytes against Legionella pneumophila-infected monocytes: characterization of the effector cell and augmentation by interleukin 2; Blanchard DK et al.; The present study was an in vitro attempt to define the effector mechanisms against the intracellular bacterium Legionella pneumophila . Monocytes from human peripheral blood leukocytes (PBL) were infected in vitro with L . pneumophila and cultured for 2 days to allow intracellular replication of the bacterium . Cells were then labeled with 51Cr and used as targets in a 4-h 51Cr-release assay . We report here that autologous nonadherent PBL effectively lysed infected monocytes, and this activity was enhanced when the effector cells were precultured with IL 2 for 2 days . The IL 2-activated killer cells were also cytolytic against uninfected cultured monocytes, but cytotoxicity was higher against Legionella-infected target cells in a dose-dependent manner . The effector cells were located in Percoll density fractions that were enriched for large granular lymphocytes . The phenotype of the effector cell activated by IL 2 was determined to be OKM1+, OKT11+, partially Leu-11+, and negative for Leu-M1, OKT4, OKT8, and Leu-7, indicating that it is neither a T cell nor a monocyte, and is possibly and NK subset that is Leu-11+ and Leu-7- . Cold target inhibition studies indicated that a similar recognition structure is shared by both infected and uninfected monocytes, but differs from that on K562 tumor target cells . Thus, in addition to tumor surveillance and controlling viral infections, killer cells can be activated to provide protection against intracellular bacterial infections.

FEBS Lett, 1987 Jul 13, 219(1), 244 - 8
Electron paramagnetic resonance and magnetic circular dichroism studies of a hexa-heme nitrite reductase from Wolinella succinogenes; Blackmore RS et al.; The nature of the heme centers in the hexa-heme dissimilatory nitrite reductase from the bacterium Wolinella succinogenes has been investigated with EPR and magnetic circular dichroism spectroscopy . The EPR spectrum of the ferric enzyme is complex showing, in addition to magnetically isolated low-spin ferric hemes with g values of 2.93, 2.3 and 1.48, two sets of signals at g = 10.3, 3.7 and 4.8, 3.21, which we assign to two pairs of exchange coupled hemes . The MCD spectra show that the isolated hemes are bis-histidine coordinated and that there is one high-spin ferric heme . The exchange coupling is lost on treatment with SDS.

Avian Dis, 1987 Jul-Sep, 31(3), 597 - 600
Lack of protection against Bordetella avium in turkey poults exposed to B . avium-like bacteria; Jackwood MW et al.; Six laboratory experiments were designed to determine whether poults infected with the nonpathogenic Bordetella avium-like (BAL) bacteria would develop immunity to B . avium (BA), the causative agent of turkey coryza . The BAL bacteria were isolated from poults given that organism, but few colonies were observed by 3 weeks postexposure . No serum-agglutinating antibody to the BAL bacterium was detected in poults exposed to that organism . Poults exposed to BAL bacteria either once or twice at different ages were not protected from infection or disease following experimental challenge between 1 and 7 weeks of age with pathogenic BA.

Can J Microbiol, 1987 Jul, 33(7), 642 - 6
Effects of temperature upon the cell-free translation system from Coxiella burnetii; Donahue JP et al.; The rate and extent of coliphage Q beta RNA translation by cell-free extracts prepared from Coxiella burnetii were studied . When translations were conducted at temperatures elevated above 37 degrees C, both polypeptide elongation and frequency of initiation were by comparison increased . The ratios of products synthesized from the polycistronic phage mRNA also changed upon increases in translation temperature, especially at 45 degrees C . Although the organism is a moderate acidophile, initiation of protein synthesis in extracts did not occur below pH 6.2, and was superior when the pH was 6.8-7.2 . The results are discussed in context with the known physiological characteristics of this obligate intracellular bacterium.

Biochem J, 1987 Jul 1, 245(1), 139 - 43
Structure of two new aminophospholipids from Methanobacterium thermoautotrophicum; Kramer JK et al.; The methanogenic bacterium Methanobacterium thermoautotrophicum (A.T.C.C . 29183) was shown to contain two new aminophospholipids . These are 2-aminoethyl phosphate ester of diphytanylglycerol diether and a sugar containing bisdiphytanyldiglycerol tetraether . The two aminophospholipids were stable to acid methanolysis except for the sugar on the bisdiphytanyldiglycerol tetraether . Strong acid (6 M-HCl) hydrolysed the alkyl ether and aminophosphate ester bonds . The structure of the phosphate linkage was demonstrated by 31P n.m.r., and the 2-ethanolamine structure was elucidated by 1H- and 13C-n.m.r . spectroscopy and by fast-atom-bombardment m.s.

J Bacteriol, 1987 Jul, 169(7), 3076 - 81
Substitution of Co alpha-(5-hydroxybenzimidazolyl)cobamide (factor III) by vitamin B12 in Methanobacterium thermoautotrophicum; Stupperich E et al.; Methanobacterium thermoautotrophicum grown on mineral medium contains 120 nmol of Co alpha-(5-hydroxybenzimidazolyl)cobamides (derivatives of factor III) per g of dry cell mass as the sole cobamide . The bacterium assimilated several corrinoids and benzimidazole bases during autotrophic growth . The corrinoids were converted into factor III; however, after three transfers in 5,6-dimethylbenzimidazole (200 microM)-supplemented mineral medium, derivatives of factor III were completely replaced by derivatives of vitamin B12, which is atypical for methanogens . The total cobamide content of these cells and their growth rate were not affected compared with factor III-containing cells . Therefore, the high cobamide content rather than a particular type of cobamide is required for metabolism of methanogens . Derivatives of factor III are not essential cofactors of cobamide-containing enzymes from methanogenic bacteria, but they are the result of a unique biosynthetic ability of these archaebacteria . The cobamide biosynthesis include unspecific enzymes, which made it possible either to convert non-species-derived corrinoids into derivatives of factor III or to synthesize other types of cobamides than factor III . The cobamide biosynthesis is regulated by its end product . In addition, the uptake of extracellular cobamides is controlled, and the assimilated corrinoids regulate cellular cobamide biosynthesis.

Mol Gen Mikrobiol Virusol, 1987 Jul, (7), 11 - 3
{Use of the plasmid R89S replicon for constructing integration vectors}; Zinchenko VV et al.; It has been shown that the plasmid R89S derivatives can be used as integrative vectors for bacteria in which the plasmid is unable to replicate autonomously . The chromosomal and plasmid fragments of phototrophic bacterium Rhodobacter sphaeroides have been cloned in plasmid pVZ365, a SmRKmR-derivative of R89S . The obtained recombinant plasmids were mobilized into R . sphaeroides cells by the I pcP-group conjugative plasmid R751 . The frequencies of the SmR-transconjugants formation are 3.7.10(-5) to 5.6.10(-3) per recipient cell . The formation of the SmR-transconjugants has not been revealed in case of the plasmid pVZ365 mobilization . The recombinant molecules containing R . sphaeroides plasmid fragments have been shown to integrate into endogenous plasmids and form cointegrates with them.

J Clin Periodontol, 1987 Jul, 14(6), 370 - 2
Cell surface hydrophobicity of Actinobacillus actinomycetemcomitans Y4; Kozlovsky A et al.; Oral bacteria colonize the dento-gingival tissues in a selective manner . Hydrophobic reactions have been suggested as one of the major mechanisms of adhesion . Hydrophobicity of Actinobacillus actinomycetemcomitans Y4 (Aa) cells was studied in vitro using adherence to the liquid hydrocarbon, octane . Adherence of Aa cells to octane varied from 60-90%, depending on the medium in which they were grown, age of the culture and the buffer in which the assay was carried out . These data suggest that Aa is a hydrophobic bacterium, the hydrophobicity of which is expressed to a varying degree, and may have a role in its adherence to oral tissues.

Infect Immun, 1987 Jul, 55(7), 1607 - 9
Evidence for sialyl glycoconjugates as receptors for Bordetella bronchiseptica on swine nasal mucosa; Ishikawa H et al.; The nature of the receptors for Bordetella bronchiseptica was investigated by using the in vitro adherence assay system . The results indicated that sialyl glycoconjugates acted as receptors on swine nasal mucosa . These results were obtained by two independent approaches: inhibition of epithelial cell adherence with sialic acid-containing compounds but not with compounds lacking sialic acid residues and loss of adherence after treatment of epithelial cells with periodate or neuraminidase . B . bronchiseptica seems to have strong affinity for mucin . This may help the bacterium to colonize the mucosal surfaces of the swine nasal cavity.

J Bacteriol, 1987 Jul, 169(7), 3035 - 43
Amino acid concentrations in Rhodospirillum rubrum during expression and switch-off of nitrogenase activity; Kanemoto RH et al.; The amino acid concentrations in the phototrophic bacterium Rhodospirillum rubrum were measured during growth under nif-repressing and nif-derepressing conditions . The effects of ammonium, glutamine, darkness, phenazine methosulfate, and the inhibitors methionine sulfoximine and azaserine on amino acid levels of cells were tested . The changes were compared to changes in whole-cell nitrogenase activity and ADP-ribosylation of dinitrogenase reductase . Glutamate was the dominant amino acid under every growth condition . Glutamine levels were equivalent when cells were grown on high-ammonia (nif-repressing) medium or glutamate (nif-derepressing) medium . Thus, glutamine is not the solitary agent that controls nif expression . No other amino acid correlated with nif expression . Glutamine concentrations rose sharply when either glutamate-grown or N-starved cells were treated with ammonia, glutamine, or azaserine . Glutamine levels showed little change upon treatment of the cells with darkness or ammonium plus methionine sulfoximine . Treatment with phenazine methosulfate resulted in a decrease in glutamine concentration . The glutamine concentration varied independently of dinitrogenase reductase ADP-ribosylation, and it is concluded that an increase in glutamine concentration is neither necessary nor sufficient to initiate the modification of dinitrogenase reductase . No other amino acid exhibited changes in concentration that correlated consistently with modification . Glutamine synthetase activity and nitrogenase activity were not coregulated under all conditions, and thus the two regulatory cascades perceive different signal(s) under at least some conditions.

Biochem Biophys Res Commun, 1987 Jun 15, 145(2), 868 - 75
Spectral properties of nitric oxide complex of cytochrome c' from Rhodopseudomonas capsulata B100; Yoshimura T et al.; The spectral properties for NO complexes of ferric and ferrous cytochrome c' from photosynthetic bacterium Rhodopseudomonas capsulata B100 are reported . The electronic absorption, MCD, and EPR spectra have been compared with those of the NO complexes of the other cytochromes c' and horse heart cytochrome c . The NO-ferrous cytochrome c' would be a mixture of NO complexes with six- and five-coordinate nitrosylheme, suggesting that the heme-iron to histidine bond in the ferrous cytochrome c' is more stable than that from chemoheterotrophic bacteria . The reaction product of ferric cytochrome c' with NO exhibited the spectra similar to NO-ferric derivatives of the other hemoproteins, which indicates the formation of NO-ferric cytochrome c'.

Mol Gen Genet, 1987 Jun, 208(1-2), 152 - 8
Effect of UTP and GTP pools on attenuation at the pyrE gene of Escherichia coli; Poulsen P et al.; We have used the galK gene, minus its promoter, to quantitate transcription of the orfE--pyrE operon of Escherichia coli in front of and after the intercistronic attenuator . Expression of the hybrid genes was studied in a bacterium with mutations that permit changes in the UTP and GTP pools during exponential growth . It was found that the greater part of pyrE gene regulation by the nucleotides takes place at the intercistronic attenuator and that promoter control contributes only little, ca . twofold . When pools of both UTP and GTP were high only 5%-6% of the mRNA chains were continued into the pyrE gene . However, when the UTP pool was reduced (from 1.3 to 0.2 mumol/g dry weight) nearly 100% of transcription passed the attenuator . Likewise, a reduction in the GTP pool (from 3.2 to 0.8 mumol/g dry weight) resulted in 25%-30% escape of attenuation . Regulation by attenuation disappeared when a premature stop-codon was introduced near the end of orfE such that translational coupling to transcription was prevented in the attenuator area . Therefore, we attribute the modulation of attenuation to nucleotide-induced variations in the kinetics of mRNA chain elongation . In support for this it was found that an RNA polymerase mutant with reduced RNA chain growth rate transcribed past the pyrE attenuator at a high frequency in the presence of a high UTP pool, but only when coupling of translation to transcription was allowed at the end of orfE.

J Bacteriol, 1987 Jun, 169(6), 2667 - 74
Nucleotide sequence of a gene cluster involved in entry of E colicins and single-stranded DNA of infecting filamentous bacteriophages into Escherichia coli; Sun TP et al.; Mutations in fii or tolA of the fii-tolA-tolB gene cluster at 17 min on the Escherichia coli map render cells tolerant to high concentrations of the E colicins and do not allow the DNA of infecting single-stranded filamentous bacteriophages to enter the bacterial cytoplasm . The nucleotide sequence of a 1,854-base-pair DNA fragment carrying the fii region was determined . This sequence predicts three open reading frames sequentially coding for proteins of 134, 230, and 142 amino acids, followed by the potential start of the tolA gene . Oligonucleotide mutagenesis of each open reading frame and maxicell analysis demonstrated that all open reading frames are expressed in vivo . Sequence analysis of mutant fii genes identified the 230-amino acid protein as the fii gene product . Chromosomal insertion mutations were constructed in each of the two remaining open reading frames . The phenotype resulting from an insertion of the chloramphenicol gene into the gene coding for the 142-amino acid protein is identical to that of mutations in fii and tolA . This gene is located between fii and tolA, and we propose the designation of tolQRA for this cluster in which tolQ is the former fii gene and tolR is the new open reading frame . The protein products of this gene cluster play an important role in the transport of large molecules such as the E colicins and filamentous phage DNA into the bacterium.

FEBS Lett, 1987 May 25, 216(1), 140 - 4
Isolation of succinate dehydrogenase from Desulfobulbus elongatus, a propionate oxidizing, sulfate reducing bacterium; Samain E et al.; Succinate dehydrogenase was purified from the particulate fraction of Desulfobulbus . The enzyme catalyzed both fumarate reduction and succinate oxidation but the rate of fumarate reduction was 8-times less than that of succinate oxidation . Quantitative analysis showed the presence of 1 mol of covalently bound flavin and 1 mol of cytochrome b per mol of succinate dehydrogenase . The enzyme contained three subunits with molecular mass 68.5, 27.5 and 22 kDa . EPR spectroscopy indicated the presence of at least two iron sulfur clusters . 2-Heptyl-4-hydroxy-quinoline-N-oxide inhibited the electron-transfer between succinate dehydrogenase and a high redox potential cytochrome c3 from Desulfobulbus elongatus.

Biochemistry, 1987 May 19, 26(10), 2740 - 6
Purification and characterization of Rhodobacter sphaeroides acyl carrier protein; Cooper CL et al.; Acyl carrier protein (ACP) has been purified from the facultative phototrophic bacterium Rhodobacter sphaeroides . The ACP preparation was greater than 95% homogeneous as determined by native and disodium dodecyl sulfate (Na2DodSO4)-polyacrylamide gel electrophoreses and N-terminal amino acid analysis . Amino acid compositional analysis revealed that the protein contains approximately 75 amino acids, has a calculated minimum molecular weight of 8700, and lacks the amino acids tyrosine and tryptophan . The presence of the characteristic 4'-phosphopantetheine prosthetic group was indicated by the occurrence of equimolar quantities of beta-alanine and taurine in amino acid hydrolysates and was confirmed by independent chemical analysis . The protein displayed a pI of 3.8 and had a calculated partial specific volume of 0.732 mL/g . The primary structure of the protein has been determined for the first 46 amino acid residues from the N terminus of the molecule, and the region of the molecule encompassing the amino acids from residues 31 to 44 was found to have 100% homology with the identical residues in Escherichia coli ACP . In contrast to E . coli ACP, R . sphaeroides ACP migrated according to its molecular weight during Na2DodSO4 gel electrophoresis, was resistant to pH-induced denaturation, and comigrated with the cis-vaccenoyl-ACP derivative during native gel electrophoresis . It is proposed that the basis for these properties is the enhanced hydrophobic character of the protein.

J Biol Chem, 1987 May 15, 262(14), 6871 - 6
Purification and characterization of a catalase-peroxidase from the photosynthetic bacterium Rhodopseudomonas capsulata; Hochman A et al.; Catalase-peroxidase was isolated from aerobically grown Rhodopseudomonas capsulata . The enzyme resembles typical catalases in some of its physicochemical properties . It has an apparent molecular weight of 236,000 and is composed of four identical subunits . It shows a typical high spin ferric heme spectrum with absorption maxima at 403 and 635 nm and shoulders at 503 and 535 nm . Upon binding of cyanide, the enzyme is converted to the low spin state, as shown by the shift of the Soret maximum to 418 nm and the band at 532 nm . It has an isoelectric point at pH 4.5 . The enzyme differs from typical catalases in also having a strong peroxidatic activity with dianisidine, pyrogallol, and diaminobenzidine as electron donors . Both the catalatic and the peroxidatic activities are similarly inactivated by treatment with 1 mM H2O2, heating to 50 degrees C, exposure to ethanol/chloroform, and photooxidative conditions . In contrast to typical catalases, but similarly to peroxidases, the enzyme is reduced by sodium dithionite . The pH optimum of the peroxidatic activity is 5-5.3 (in contrast to 6-6.5 of the catalatic activity) . 50% of the apparent maximal activities are reached at 0.3 and 4.2 mM H2O2 for the peroxidatic and catalatic activities, respectively . Both enzymic activities are equally inhibited by cyanide, 50% inhibition being achieved with 2.2 X 10(-5) M KCN . Contrarily, the two activities differ in their response to hydroxylamine and azide . 50% inhibition of the catalatic activity is obtained with 1.5 X 10(-4) M azide or 2.15 X 10(-6) M hydroxylamine; 50% inhibition of the peroxidatic activity requires 7.3 X 10(-4) M azide or 7.8 X 10(-5) M hydroxylamine . The activation energies of the catalatic and the peroxidatic activities are 1.9 and 1.7 kcal/mol, respectively.

J Immunol Methods, 1987 May 4, 99(1), 101 - 6
Separation of human IgA1 and IgA2 using jacalin-agarose chromatography; Gregory RL et al.; A lectin isolated from the tropical jackfruit, jacalin, previously reported to precipitate human immunoglobulin A (IgA), and conjugated to agarose was used to separate the two subclasses of IgA from secretions . Jacalin-agarose binds specifically to the D-galactose moiety of IgA1 but not to IgA2 which has a different carbohydrate content and structure . IgA2 passed through the jacalin-agarose column and was collected in the void volume . IgA1 was eluted from the lectin by 0.8 M galactose . Of a representative diluted anti-alpha chain-purified colostral IgA preparation containing 50.2 micrograms IgA1 and 55.8 micrograms IgA2, 40.3 micrograms IgA1 (80.3% of the original) and 49.6 micrograms IgA2 (88.9%) was collected following jacalin-agarose chromatography . The jacalin-purified IgA1 fraction contained 8.0% IgA2 and the IgA2 fraction contained no IgA1 . In addition, the IgA1 and IgA2 fractions had naturally occurring antibody activity to a normal oral bacterium . The method is easy, reproducible and specific and has many applications to mucosal immunological investigations.

J Bacteriol, 1987 May, 169(5), 1979 - 84
Contraction of filaments of Escherichia coli after disruption of cell membrane by detergent; Koch AL et al.; The osmotic pressure within a living bacterium creates stresses in the peptidoglycan that stretch the sacculus . We measured the amount of stretch by monitoring the shrinkage of growing cells of Escherichia coli after removal of the osmotic pressure by disruption of the phospholipid membranes with sodium dodecyl sulfate . Because the rods of the wild type are so short, length changes of filaments of longer than 7 microns were measured on phase-contrast micrographs . The filaments were prepared by growing ftsA and ftsI strains under permissive conditions in rich medium and then shifting them to 42 degrees C for 40 to 180 min . During this time, the mutant cells became elongated but did not divide . The growing filaments were mounted on a glass surface that had been treated with poly-L-lysine or RNase . The filaments were photographed before being treated with sodium dodecyl sulfate . The filaments were rephotographed at the time when the first change in phase contrast was noted . Some filaments were also measured at 10-min time intervals from 0 to 60 min . The reduction in phase contrast signaled the leakage of solutes and the loss of turgor pressure . The average length of the filaments decreased 17% . If the circumference were stretched to the same degree, then the surface area in vivo would be 45% greater than in the relaxed state . For comparison, a fully cross-linked monolayer of E . coli peptidoglycan in its most compact conformation could stretch up to 300% in achieving the most extended conformation possible without splitting covalent bonds.

Isr J Med Sci, 1987 May, 23(5), 414 - 7
Localization of spiralin in Escherichia coli cells transformed with the recombinant plasmid pESI; Blanchard A et al.; The expression of spiralin in the transformant strain HB101 Tsp of Escherichia coli has been investigated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), immunodetection after electrotransfer, and crossed immunoelectrophoresis . The protein has been sought in whole cells, cytoplasm, and plasma and outer membranes of the bacterium . Untransformed E . coli cells and Spiroplasma citri cells were used as negative and positive references, respectively . Contrary to earlier claims, spiralin was detected not only in the cytoplasm of E . coli, but also in the inner and outer membranes . In addition, our results show that the protein was not secreted by the bacterium . Three forms of spiralin could be distinguished with respect to differences in apparent molecular mass: 27.5, 29.5 and 30 kilodalton (kDa) . The presence of the high molecular mass polypeptide in the two membranes of E . coli invalidates the hypothesis according to which the 27.5-kDa (or 28-kDa) species is a mature form derived from the 30-kDa (or 30.5-kDa) species by the amputation of a signal sequence . Since spiralin is an acyl protein, the possibility of variation in the extent of acylation of the protein in E . coli, with subsequent variation of the apparent molecular mass, should be taken into account.

J Bacteriol, 1987 May, 169(5), 2307 - 9
Immunoelectron microscopic demonstration of ATPase on the cytoplasmic membrane of the methanogenic bacterium strain Göl; Mayer F et al.; ATPase was shown to be present on the cytoplasmic membrane of the methanogenic bacterium strain Gol . The enzyme was identified by an immunoelectron microscopic technique by using polyclonal antiserum directed against the beta subunit of Escherichia coli F0F1-ATPase . Negatively stained membrane vesicles exhibited a dense population of stalked particles similar in dimensions and fine structure to typical F0F1-ATPase particles.

Mol Cell Biol, 1987 May, 7(5), 1623 - 8
Use of the Escherichia coli gene for asparagine synthetase as a selective marker in a shuttle vector capable of dominant transfection and amplification in animal cells; Cartier M et al.; A new dominant amplifiable selective system for use in bacterium-animal cell shuttle vectors was developed by the insertion of a 2-kilobase genomic fragment containing the cloned Escherichia coli gene for asparagine synthetase (AS) into the pBR322-simian virus 40 recombinant vector pSV2 so as to place the translational initiator codon for the bacterial AS about 1,000 base pairs downstream from the simian virus 40 early promoter . This new construct, pSV2-AS, retains bacterial sequences for transcriptional and translational initiation and so can express AS in bacteria . The construct can also complement AS- mutants of mammalian cells, giving AS+ transfectants capable of growth in medium lacking asparagine, with relatively high efficiency (about 300 colonies per microgram of DNA per 10(6) cells exposed) . The vector can be amplified up to 100-fold in such AS+ transfectants by selection in asparagine-free medium containing increasing concentrations of the AS inhibitor beta-aspartyl hydroxamate . AS+ transfectants were found to be much more resistant to a second AS inhibitor, Albizziin, than were normal AS+ animal cell lines . This difference, which may indicate a strong resistance of the bacterial AS enzyme to Albizziin, was exploited to develop an effective selection for bacterial AS transfectants of a number of wild-type AS+ cell lines of rat, Chinese hamster, mouse, and human origin . LR-73 cells, a Chinese hamster AS+ cell line, were transfected with pSV2-AS with an efficiency of about 1,000 colonies per 0.5 microgram of DNA per 10(6) cells . The integrated construct in these cells was amplified by incubation of the transfectants in increasing concentrations of beta-aspartyl hydroxamate . Advantages and disadvantages of this new dominant, selectable, and amplifiable marker over markers commonly used in shuttle vectors are discussed.

Infect Immun, 1987 May, 55(5), 1216 - 23
Pilus-mediated binding of bovine enterotoxigenic Escherichia coli to calf small intestinal mucins; Mouricout MA et al.; In this study we show that the adhesion to mucus of the enterotoxigenic Escherichia coli strains responsible for diarrhea in calves involves a bacterium-mucin recognition phenomenon in which the bacterial pili and specific mucus receptors carried by the glycoproteins (2,000 to 400 kilodalton) play a major role . An adhesion maximum was observed at a pH of less than 6 (4.75 to 5.25) . The sialic acids and galactose appeared to be at least partly responsible for the attachment of K99 pili, whereas F41 pili preferentially recognized desialylated receptors . The attachment of different strains of E . coli characterized by the presence of the three main pili, K99, F41, and FY, known to be responsible for the binding of enterotoxigenic E . coli to the intestinal epithelium of the calf, was studied using Scatchard and Hill analyses . The attachment mechanism of bacteria carrying K99 pili showed positive cooperativity . FY and F41 pili recognized independent receptor sites, the first on sialylated mucus and the second on sialidase-treated mucus . Moreover, F41 pili were found to bind the native mucus according to a negative cooperativity phenomenon . Finally, the recognition sites carried by bacterial pilins may be saturated by some animal glycoprotein glycans which are therefore adhesion inhibitors.

Biochem Biophys Res Commun, 1987 Apr 14, 144(1), 143 - 51
Extracellular endoglucanase activity by a novel bacterium isolated from marine shipworm; Griffin HL et al.; An extracellular enzyme preparation from shipworm bacterium cultures dramatically increased reducing sugar content of carboxymethylcellulose (CMC3), but did not solubilize sugar from particulate cellulose . The preparation degraded cellodextrins larger than cellotriose (G3) . Only interior cellodextrin chain linkages were cleaved and the center-most bond of cellohexaose (G6) was preferentially cleaved . Activity maxima were observed at 60 degrees C and between pH 5.0 and 7.0 . The activity was resistant to protease treatment and little loss of activity was observed after 14 d at 25 degrees C.

Biochem Biophys Res Commun, 1987 Apr 14, 144(1), 224 - 31
Spectral properties of cytochrome c' from Rhodopseudomonas capsulata B100 and its CO complex; Yoshimura T et al.; The spectral properties of cytochrome c' from photosynthetic bacterium Rhodopseudomonas capsulata (= Rhodobacter capsulatus) B100 and its CO complex are reported . The electronic absorption, MCD, and EPR spectra have been compared with those of the other cytochromes c' and horse heart cytochrome c . EPR and electronic spectral results for the ferric cytochrome c' suggest that the ground state of heme-iron(III) at neutral pH consists of a quantum mechanical admixture of an intermediate-spin and a high-spin state and that at pH 11.0 is in a high-spin state . In the MCD spectrum of the CO-ferrous cytochrome c', the MCD intensity in the Soret band region was much higher than that of CO complexes of hemoproteins with a protoheme . The differences in a stereochemistry of the sixth-coordination position is discussed.

J Gen Microbiol, 1987 Apr, 133 ( Pt 4), 961 - 6
DNA repair systems in the phototrophic bacterium Rhodobacter capsulatus; Barbe J et al.; UV irradiation and mitomycin C exposure trigger a protease-activity-dependent inhibition of cell division in Rhodobacter capsulatus, which begins about 2 h after the treatment is applied . UV irradiation also induces a dose-dependent mutagenesis with a maximal rate between 5 and 10 J m-2, with increased synthesis of a protein of Mr approximately 30,000 between 2 and 3 h after UV irradiation . In addition, R . capsulatus has an efficient photoreactivation system that reverses the lethal effects of UV irradiation in the presence of intense visible light.

J Clin Gastroenterol, 1987 Apr, 9(2), 194 - 7
Multiple Fusobacterium nucleatum liver abscesses . Association with a persistent abnormality in humoral immune function; Tweedy CR et al.; A previously healthy 29-year-old man developed multiple hepatic abscesses secondary to Fusobacterium nucleatum . No underlying local disease was found . The leading portal of entry for the bacterium may have been the oral cavity; 4 days before the onset of his illness he had had extensive dental work . Immunological evaluation during the illness and in late convalescence (16 weeks after onset) revealed a persistent B cell abnormality characterized by markedly depressed in vitro secretion of immunoglobulins in response to pokeweed mitogen; however, serum immunoglobulins and IgG subclasses were normal . Abnormal numbers of suppressor T cells (OKT8+) and increased suppressor function were also present . Anaerobic pyogenic liver abscesses may occur in the absence of obvious underlying disease, but this case suggests that there may be an association with in vitro abnormalities of the immune system.

Avian Dis, 1987 Apr-Jun, 31(2), 277 - 86
Pili of Bordetella avium: expression, characterization, and role in in vitro adherence; Jackwood MW et al.; Electron microscopy revealed pili on all isolates of Bordetella avium and B . avium-like bacteria examined . Trypticase soy broth (TSB) and 2% peptone agar were the best media for promoting pilus expression . Cultures grown at 37 or 42 C had similar pilus production, whereas cultures grown at 18 C produced few or no pili . Pilus expression of the Art Vax strain was best when that strain was grown in TSB, but the strain yielded fewer pili than B . avium and B . avium-like isolates grown under the same cultural conditions . B . avium pili had a diameter of 2.0 nm, ranged in length from 370 nm to 1500 nm, and had a protein subunit molecular mass of about 13,100 daltons . Purified pili from B . avium did not hemagglutinate guinea pig erythrocytes, and a 1:20 dilution of hyperimmune antisera against B . avium pili did not block the hemagglutinating activity of whole-cell preparations of B . avium . In the indirect immunofluorescence test, B . avium isolates and the Art Vax strain adhered to the tracheal explants of turkeys, but B . avium-like isolates did not . Purified pili from B . avium adhered to the surface of the mucosal lining of the tracheal explants, and hyperimmune antisera against B . avium pili blocked the in vitro adherence of whole-cell preparations of B . avium . It was concluded that pili of B . avium are involved in the in vitro attachment of that bacterium to the mucosal surface of turkey tracheal explants.

J Bacteriol, 1987 Apr, 169(4), 1522 - 8
Identification of the RNA products of the ops gene of Myxococcus xanthus and mapping of ops and tps RNAs; Downard JS; The expression of the ops gene, like that of the highly homologous and closely linked tps gene, is induced during development of the fruiting bacterium Myxococcus xanthus . The RNA products of the ops gene have been identified and compared with tps RNA . The ops RNA was observed in developmental cells only after spore formation had commenced, and it was necessary to use a sporulation-defective mutant strain or to disrupt spores to isolate this RNA . RNA from the ops gene was not observed in vegetative cells but was readily detected in cells subjected to glycerol-induced sporulation . In contrast, a large amount of developmental tps RNA was observed in cells well before sporulation had occurred; low levels of tps RNA were observed in vegetative cells; and only a slight increase in tps RNA was found during glycerol-induced sporulation . Several ops and tps RNAs were observed in this study, and the positions of these RNAs were mapped on the M . xanthus genome . The 5' ends of both the ops and tps RNAs mapped predominantly to positions about 50 bases upstream from the respective translational initiation sites . The 3' ends of RNAs from both genes were heterogeneous . The four ops RNAs were 620, 775, 845, and 1,230 bases in length, while the tps RNAs were 612, 695, 730, and 935 bases.

J Mol Biol, 1987 Mar 5, 194(1), 71 - 80
Cascade regulation of Caulobacter flagellar and chemotaxis genes; Champer R et al.; The assembly of a functional flagellum in the bacterium Caulobacter crescentus requires the protein products of approximately 30 genes expressed in a temporally discrete and spatially distinct manner . Our current understanding of this system has been limited by the fact that purified protein products are available for only about one-fifth of these genes . A genetically engineered transposon promoter probe, Tn5-VB32, containing a promoterless gene encoding neomycin phosphotransferase II (NPTase II) was used to generate a series of non-motile (fla-), kanamycin resistant strains of C . crescentus . These transcription-fusions allow the expression of NPTase II to be controlled by flagellar promoters, and thus questions of temporal regulation of flagellar genes can be addressed without the need to obtain purified protein products . The flagellar promoters accessed by Tn5-VB32 exhibited temporal regulation analogous to the known flagellar and chemotaxis gene products . The expression of NPTase II in these mutants is read from a chimeric mRNA that initiates in a chromosomal fla promoter and continues through the inserted NPTase II gene . Thus, temporal regulation is controlled by modulating either the initiation of transcription, or transcript turnover, at specific times in the cell cycle . Epistatic interactions between the genes accessed by the promoter probe and other flagellar loci were studied in double fla mutants generated by transducing the promoter-probe mutations into spontaneously derived second-site fla-mutant backgrounds . The synthesis of both natural fla gene products and the accessed NPTase II was assayed in these strains using antisera to purified components of the flagellum and to purified NPTase II . On the basis of these interactions, a trans-acting hierarchy of flagellar and chemotaxis gene expression is proposed.

Biochim Biophys Acta, 1987 Feb 23, 917(3), 365 - 71
Purification and characterization of NADP-linked acetoacetyl-CoA reductase from Zoogloea ramigera I-16-M; Fukui T et al.; An NADP-linked acetoacetyl-CoA reductase was purified to electrophoretic homogeneity from Zoogloea ramigera I-16-M, a poly(3-hydroxybutyrate)-accumulating bacterium . The purified enzyme showed specific activity of 412 mumol acetoacetyl-CoA reduced per min per mg protein, which constituted an 880-fold purification compared to the crude extract, with a 32% yield . Electrophoretic analysis of the purified enzyme which had been cross-linked with dimethylsuberimidate showed that the native enzyme (Mr 92,000) is a tetramer of four identical subunits (Mr 25,500) . Among the various D-(-)- and L-(+)-3-hydroxyacyl-CoAs tested, the purified enzyme oxidized only D-(-)-3-hydroxybutyryl-CoA and to a lesser extent D-(-)-3-hydroxyvaleryl-CoA in the presence of NADP+ . The antiserum prepared against the purified enzyme completely inhibited poly(3-hydroxybutyrate) synthesis from acetyl-CoA by a crude extract of Z . ramigera I-16-M cells . These findings indicate that this enzyme plays an indispensable role as the supplier of D-(-)-3-hydroxybutyryl-CoA in poly(3-hydroxybutyrate) synthesis in this bacterium.

Nature, 1987 Feb 19-25, 325(6106), 728 - 30
Coevolution of codon usage and transfer RNA abundance; Bulmer M; The use of synonymous codons is strongly biased in the bacterium Escherichia coli and yeast, comprising both bias between codons recognized by the same transfer RNA and bias between groups of codons recognized by different synonymous tRNAs . A major determinant of the second sort of bias is tRNA content, codons recognized by abundant tRNAs being used more often than those recognised by rare tRNAs, particularly in highly expressed genes, probably owing to selection at the level of translation against codons recognized by rare tRNAs . Conversely, codon usage is likely to exert selection pressure on tRNA abundance . Here I develop a model for the coevolution of codon usage and tRNA abundance which explains why there are unequal abundances of synonymous tRNAs leading to biased usage between groups of codons recognized by them in unicellular organisms.

Eur J Biochem, 1987 Feb 16, 163(1), 161 - 6
The complete amino acid sequence of rubredoxin from the green phototrophic bacterium Chlorobium thiosulphatophilum strain PM; Woolley KJ et al.; A complete amino acid sequence for the rubredoxin from the photosynthetic bacterium Chlorobium thiosulphatophilum is proposed . The sequence, a single polypeptide chain of 53 amino acids, was deduced from the sequences of peptides obtained by chymotryptic, tryptic, thermolytic or mild acid digestion . The rubredoxin shows a high degree of sequence homology with rubredoxins from non-photosynthetic bacteria, and the evolutionary implications of this are considered.

Eur J Biochem, 1987 Feb 2, 162(3), 547 - 54
Characterization of the cytochrome system of a nitrogen-fixing strain of a sulfate-reducing bacterium: Desulfovibrio desulfuricans strain Berre-Eau; Moura I et al.; Two c-type cytochromes were purified and characterized by electron paramagnetic resonance (EPR) and nuclear magnetic resonance (NMR) spectroscopic techniques, from the sulfate-reducer nitrogen-fixing organism, Desulfovibrio desulfuricans strain Berre-Eau (NCIB 8387) . The purification procedures included several chromatographic steps on alumina, carboxymethylcellulose and gel filtration . A tetrahaem and a monohaem cytochrome were identified . The multihaem cytochrome has visible, EPR and NMR spectra with general properties similar to other low-potential bis-histidinyl axially bound haem proteins, belonging to the class of tetrahaem cytochrome c3 isolated from other Desulfovibrio species . The monohaem cytochrome c553 is ascorbate-reducible and its EPR and NMR data are characteristic of a cytochrome with methionine-histidine ligation . Their properties are compared with other homologous proteins isolated from sulfate-reducing bacteria.

Infect Immun, 1987 Feb, 55(2), 487 - 9
Binding of Actinomyces naeslundii to glycosphingolipids; Brennan MJ et al.; The type 2 fimbrial lectin of Actinomyces naeslundii WVU45 mediated the binding of this bacterium to glycosphingolipids chromatographed on thin-layer silica gel plates . Radioiodinated bacteria attached to GM1, GD1b, and globoside . After chromatograms were treated with sialidase, the bacteria also bound to GD1a and GT1b . The actinomyces lectin apparently recognized the Gal beta 3GalNAc termini of these gangliosides and the GalNAc beta 3Gal terminus of globoside, suggesting that glycolipids containing these sequences may serve as receptors for A . naeslundii on mammalian cells.

J Bacteriol, 1987 Feb, 169(2), 514 - 8
Unidirectional, intermittent rotation of the flagellum of Rhodobacter sphaeroides; Armitage JP et al.; The single flagellum of the photosynthetic bacterium Rhodobacter sphaeroides was found to be medially located on the cell body . Observation of free-swimming bacteria, and bacteria tethered by their flagellar filaments, revealed that the flagellum could only rotate in the clockwise direction; switching of the direction of rotation was never observed . Flagellar rotation stopped periodically, typically several times a minute for up to several seconds each . Reorientation of swimming cells appeared to be the result of Brownian rotation during the stop periods . The flagellar filament displayed polymorphism; detached and nonrotating filaments were usually seen as large-amplitude helices of such short wavelength that they appeared as flat coils or circles, whereas the filaments on swimming cells showed a normal (small-amplitude, long-wavelength) helical form . With attached filaments, the transition from the normal to the coiled form occurred when the flagellar motor stopped rotating, proceeding from the distal end towards the cell body . It is possible that both the relaxation process and the smaller frictional resistance after relaxation may act to enhance the rate of reorientation of the cell . The transition from the coiled to the normal form occurred when the motor restarted, proceeding from the proximal end outwards, which might further contribute to the reorientation of the cell before it reaches a stable swimming geometry.

J Gen Microbiol, 1987 Feb, 133 ( Pt 2), 353 - 60
Co-adaptation of Escherichia coli and coliphage lambda vir in continuous culture; Spanakis E et al.; Populations of the bacterium Escherichia coli and of its phage lambda vir appeared to equilibrate in continuous cultures . The bacterial end-populations were heterogeneous in respect of their resistance to lambda vir and their ability to utilize maltose . The most competitive of the selected bacteria were mutants which had a reduced rate of synthesis of lambda-receptor so as to become highly, but not totally, resistant to the phage . The coexisting phage had an increased affinity for the receptor and an altered antigenic specificity, suggesting adaptation of its adsorption site in response to the evolution of resistance in the bacteria.

Mol Gen Mikrobiol Virusol, 1987 Feb, (2), 12 - 6
{Mobilization of the pACYC184 plasmid by hybrid pAS8-121 delta plasmids in Escherichia coli cells}; Muronets EM et al.; The plasmid pACYC184 is shown to be mobilized for conjugal transfer in Escherichia coli cells by the deleted (Tn7-TcR) derivatives of the hybrid conjugative plasmid pAS8-121 (RP4-Co1E1) . Both the mobilized and mobilizing plasmids are autonomously inherited by the recipient cells when the mobilizing plasmid carries single copy of IS8 (the plasmid pAS8-121 delta 16) . Cointegrates pAS8-121 delta 16D:: ::pACYC184 are found in the recipient cells with pACYC184 being inserted between two repeats of IS8 if the derivate plasmid pAS8-121 delta 16D having the duplication of IS8 is used to mobilize pACYC184 for conjugal transfer . The insertion of pACYC184 between IS8 repeats in the plasmid pAS8-121 delta 16D eliminates the plasmid ability to be inserted with high frequency into the chromosome of the phototrophic bacterium R . sphaeroides 2R . The cointegrate pAS8-121 delta 16D:: pACYC184 is stable but can be resolved during the transformation deriving the plasmid pACYC184:: IS8 . The latter may be used as a probe for isolation and analysis of IS8 DNA sequences and for constructing the vectors on the basis of pACYC184.

Infect Immun, 1987 Feb, 55(2), 433 - 7
Induction of tumor necrosis factor by Legionella pneumophila; Blanchard DK et al.; Mice were inoculated with Legionella pneumophila via an intratracheal route to establish an experimental model of infection . Lung lavage fluid obtained from infected mice contained a cytolytic factor identified as tumor necrosis factor (TNF) . Peak levels of TNF were produced at about 24 h postinfection and rapidly declined thereafter . Treatment of the mice with dextran sulfate before inoculation with the bacteria resulted in lowered amounts of TNF in the lung lavage fluid, suggesting that macrophages were responsible for production of the cytokine . Furthermore, cultures of adherent lung leukocytes and a macrophage cell line, PU 5-1.8, were stimulated to produce TNF by exposure to Legionella antigens . In addition, adherent lung leukocytes from Legionella-infected mice spontaneously released TNF into the culture supernatant . Inoculation of mice with saline or latex particles failed to induce TNF in vivo, indicating that bacterial antigens or products were the stimulating signals . Since there was no detectable TNF activity in sera at any time after intratracheal inoculation, TNF production appeared to be confined to the site of infection . Pretreatment of PU 5-1.8 cultures with gamma interferon, which was detected in the lung lavage fluid before TNF, resulted in augmented TNF production, suggesting cooperativity may exist between the two cytokines, either in the pathogenicity of the bacterium or in a possible immunomodulatory function of TNF and interferon during infection.

J Biol Chem, 1987 Jan 25, 262(3), 1144 - 7
Spectroscopic and kinetic properties of an oxygen-binding heme protein from Chromatium vinosum; Gaul DF et al.; Resonance Raman and electron paramagnetic resonance spectroscopy have been utilized to identify histidine as an axial heme ligand in a high spin, heme c-containing protein isolated from the photosynthetic purple sulfur bacterium Chromatium vinosum . Resonance Raman spectroscopy has also been used to characterize the CO adduct of the C . vinosum hemoprotein . Resonance Raman spectra of the heme site obtained within 10 ns of CO photolysis from the ferrous hemoprotein are virtually identical to those of the unligated protein, indicating that there is little or no rearrangement of the heme pocket in response to ligand photolysis . The equilibrium constant for CO binding to the ferrous hemeprotein was measured to be 1.7 X 10(-5) M-1 and the CO association rate constant determined to be 5.4 X 10(3) M-1 S-1 . The quantum efficiency for photodissociation of the hemoprotein X CO complex was greater than or equal to 0.9.

FEBS Lett, 1987 Jan 19, 211(1), 53 - 8
Structure of the porin from a bacterial stalk; Chalcroft JP et al.; The stalks (hyphae) of a prosthecate bacterium, directly sampled from the water surface of a hot pond, show extended regular patterns on their envelope in the electron microscope . Image processing revealed a structure of the crystalline complexes which is very similar to the gross morphology of the Escherichia coli porins OmpC and OmpF . The natural two-dimensional crystal of the outer membrane protein has p3 symmetry and a lattice constant of 7.95 nm . The three-dimensional structure of the stalk porin has been determined to an almost isotropic resolution of 1.7 nm . The reconstruction revealed a complex network of channels within the membrane matrix with a triplet of pores merging into a common outlet, similar to the structure of the E . coli porin OmpF in reconstituted membranes . In addition, a blindly ending pore exists which appears to be connected to the continuous pores via small channels . The significance of the regularly arrayed porin cylinders with respect to the shape and function of the stalks is discussed.

Eur J Biochem, 1987 Jan 15, 162(2), 413 - 8
Cloning and expression in Escherichia coli of a hygromycin B phosphotransferase gene from Streptomyces hygroscopicus; Zalacain M et al.; The Streptomyces hygroscopicus hyg gene encoding a hygromycin B phosphotransferase has been introduced into different sites of both the Escherichia coli plasmid pBR322 and the Escherichia coli-Saccharomyces cerevisiae shuttle vector YRp7 . When this gene was inserted into the BamHI site of pBR322 and then cloned in E . coli phosphorylating activity was not detected, indicating that the hyg gene promoter was not functional in this bacterium . However, when the hyg gene was inserted into either the unique PstI site of pBR322 or into each of the two PstI sites of YRp7, phosphotransferase activity was observed . Analysis of the translation products from these constructions by coupled in vitro transcription-translation systems suggested that in all cases transcrition was regulated by a promoter not provided by the inserted hyg gene and that the synthesized polypeptide was identical to that present in S . hygroscopicus.

Gene, 1987, 54(1), 133 - 9
Structure of the Bradyrhizobium japonicum gene hemA encoding 5-aminolevulinic acid synthase; McClung CR et al.; The nucleotide (nt) sequence of the hemA gene, which encodes 5-aminolevulinic acid synthase (ALAS) from the bacterium Bradyrhizobium japonicum, is presented . This sequence predicts a protein of 408 amino acids (aa) with an Mr of 44,599 . This predicted amino acid sequence is highly homologous to that of the chicken embryonic liver ALAS, exhibiting a 48.8% identical amino acid sequence over the entire length of the bacterial protein . A single mRNA start point was demonstrated by S1 protection analysis for the B . japonicum hemA . The 5' end of the transcript is 100 nt upstream from the start codon . The sequence of the promoter region has some sequence homology to the -35 nt region of the Escherichia coli consensus promoter sequence but not to the -10 nt region . There is also one block of 9 nt found in both the B . japonicum glnA and hemA promoter regions.

Biomed Biochim Acta, 1987, 46(5), 413 - 8
Influence of autoclaved Brucella melitensis on the proliferation of human lymphocytes; Tietz HJ et al.; Brucella melitensis is a facultative intracellular bacterium which binds spontaneously to human B-lymphocytes . In order to find out whether there exists a relation between bacterial adherence and lymphocyte reactivity, the proliferation response of normal adult peripheral blood lymphocytes to autoclaved B . melitensis has been studied . Our results indicate that autoclaved B . melitensis induce only a slight increase in proliferation . This low lymphocyte response is due to proliferating B-cells . In high doses B . melitensis inhibited the response of lymphocytes to Concanavalin A and phytohaemagglutinin . This effect is probably due to the presence of lectin binding saccharides on the bacterial surface competing with the T-cells for the mitogens.

Prog Clin Biol Res, 1987, 253, 151 - 62
The detection of neurotoxicant activity by a bacterial toxicity assay; Reinhartz A et al.; We present and evaluate a simple, rapid (2 hrs), colorimetric assay for the detection of toxicants, including neurotoxicants . The assay is based on the ability of toxicants to inhibit the de novo synthesis of an inducible enzyme, beta-galactosidase, by a rough mutant of E . coli, which is highly sensitive to a wide spectrum of toxic substances . The test is performed under stress conditions for the bacterium, since under such conditions better sensitivity for low concentrations of analytes is obtained . In the assay, the sample is mixed with the stressed bacteria and a cocktail containing the specific inducer for the chromogenic enzyme and factors essential to the recovery of the bacteria from their stressed condition . The ability of cells to synthesize B-galactosidase under these conditions depends on their ability to recover from the stress . Toxic materials interfere and/or inhibit the recovery process and with it the synthesis of beta-galactosidase.

Mol Cell Biol, 1987 Jan, 7(1), 218 - 24
DNA mismatch repair detected in human cell extracts; Glazer PM et al.; A system to study mismatch repair in vitro in HeLa cell extracts was developed . Preformed heteroduplex plasmid DNA containing two single base pair mismatches within the SupF gene of Escherichia coli was used as a substrate in a mismatch repair assay . Repair of one or both of the mismatches to the wild-type sequence was measured by transformation of a lac(Am) E . coli strain in which the presence of an active supF gene could be scored . The E . coli strain used was constructed to carry mutations in genes associated with mismatch repair and recombination (mutH, mutU, and recA) so that the processing of the heteroduplex DNA by the bacterium was minimal . Extract reactions were carried out by the incubation of the heteroduplex plasmid DNA in the HeLa cell extracts to which ATP, creatine phosphate, creatine kinase, deoxynucleotides, and a magnesium-containing buffer were added . Under these conditions about 1% of the mismatches were repaired . In the absence of added energy sources or deoxynucleotides, the activity in the extracts was significantly reduced . The addition of either aphidicolin or dideoxynucleotides reduced the mismatch repair activity, but only aphidicolin was effective in blocking DNA polymerization in the extracts . It is concluded that mismatch repair in these extracts is an energy-requiring process that is dependent on an adequate deoxynucleotide concentration . The results also indicate that the process is associated with some type of DNA polymerization, but the different effects of aphidicolin and dideoxynucleotides suggest that the mismatch repair activity in the extracts cannot simply be accounted for by random nick-translation activity alone.

Gene, 1987, 56(1), 99 - 108
A system for in vivo selection of genomic rearrangements with predetermined endpoints in Escherichia coli using modified Tn10 transposons; Francois V et al.; Using recombinant DNA techniques, the Tn10-specific tetA gene (coding for tetracycline resistance) has been mutagenized by insertion of a streptomycin-resistance or a kanamycin-resistance gene . The insertions occurred at loci separated by 920 bp . The mutated tetA fragments, respectively designated as Tes (for tetracycline-streptomycin) and Tek (for tetracycline-kanamycin), were subsequently cloned into a phage lambda cIII+cIts857cII+ in replacement of the att lambda region . The two recombinant phages are convenient delivery vehicles which permit the in vivo substitution of the tetA locus of any Tn10 insertion with the Tes or the Tek fragment . The procedure involves two selectable steps: (i) integration of a lambda-Tes (or lambda-Tek) prophage into the Tn10 of interest; (ii) excision of the prophage by a second exchange which leaves the extra resistance gene installed within the Tn10 . A major interest of the system is that, once a bacterium carries both Tn10-Tes and Tn10-Tek insertions, a recombination event between the two Tn10 sequences can reconstitute an active tetA gene . This selectable event may be associated with the rearrangement of the sequences surrounding the transposons . This unique property of the "Tes and Tek" system makes it very useful for selection of genomic rearrangements using the Tn10-Tes and Tn10-Tek as predetermined endpoints . The successful isolation of a chromosomal inversion is reported.

Biochem Biophys Res Commun, 1986 Dec 15, 141(2), 562 - 8
On the structure and linkage of the covalent cofactor of methylamine dehydrogenase from the methylotrophic bacterium W3A1; McIntire WS et al.; Short amino acid sequences around the two linkage sites of the cofactor of methylamine dehydrogenase are presented . Mass spectral data indicates that the covalently bound cofactor is the tricyclic pyrroloquinoline quinone (PQQ) . However, the 3 carboxyl groups characteristic of this o-quinone are absent . A cysteine thioether, via a methylene bridge, and a serine ether link the cofactor to the small subunit of methylamine dehydrogenase.

FEBS Lett, 1986 Dec 15, 209(2), 261 - 4
Preliminary X-ray studies of the tetra-heme cytochrome c3 and the octa-heme cytochrome c3 from Desulfovibrio gigas; Sieker LC et al.; A tetra-heme and an octa-heme cytochrome c3 from the sulfate bacterium Desulfovibrio gigas have been crystallized . Diffraction quality crystals of the tetra-heme cytochrome are obtained from solution by the addition of polyethylene glycol at pH 6.5 . The crystals are orthorhombic, space group P2(1)2(1)2 with unit cell parameters a = 42.27 A, b = 52.54 A and c = 52.83 A . The octa-heme cytochrome crystals develop from low ionic strength solutions of phosphate or Tris-Cl in the pH range 6.2-7.6 . The crystals belong to the trigonal system, space group P3(1) or the enantiomorph P3(2), with unit cell parameters a = b = 57.4 A, c = 97.3 A, gamma = 120 degrees . Single crystal diffraction studies of the structures of these two low-potential cytochromes are in progress.

Biochim Biophys Acta, 1986 Dec 3, 852(2-3), 203 - 11
Characterization of purified cytochrome c1 from Rhodobacter sphaeroides R-26; Yu L et al.; Cytochrome c1 from a photosynthetic bacterium Rhodobacter sphaeroides R-26 has been purified to homogeneity . The purified protein contains 30 nmol heme per mg protein, has an isoelectric point of 5.7, and is soluble in aqueous solution in the absence of detergents . The apparent molecular weight of this protein is about 150,000, determined by Bio Gel A-0.5 m column chromatography; a minimum molecular weight of 30,000 is obtained by sodium dodecylsulfate polyacrylamide gel electrophoresis . The absorption spectrum of this cytochrome is similar to that of mammalian cytochrome c1, but the amino acid composition and circular dichroism spectral characteristics are different . The heme moiety of cytochrome c1 is more exposed than is that of mammalian cytochrome c1, but less exposed than that of cytochrome c2 . Ferricytochrome c1 undergoes photoreduction upon illumination with light under anaerobic conditions . Such photoreduction is completely abolished when p-chloromercuriphenylsulfonate is added to ferricytochrome c1, suggesting that the sulfhydryl groups of cytochrome c1 are the electron donors for photoreduction . Purified cytochrome c1 contains 3 +/- 0.1 mol of the p-chloromercuriphenylsulfonate titratable sulfhydryl groups per mol of protein . In contrast to mammalian cytochrome c1, the bacterial protein does not form a stable complex with cytochrome c2 or with mammalian cytochrome c at low ionic strength . Electron transfer between bacterial ferrocytochrome c1 and bacterial ferricytochrome c2, and between bacterial ferrocytochrome c1 and mammalian ferricytochrome c proceeds rapidly with equilibrium constants of 49 and 3.5, respectively . The midpoint potential of purified cytochrome c1 is calculated to be 228 mV, which is identical to that of mammalian cytochrome c1.

Arch Biochem Biophys, 1986 Dec, 251(2), 479 - 86
Purification and properties of biotinyl-CoA synthetase from Mycoplana sp . No . 166; Tanaka M et al.; Biotinyl-CoA synthetase, the first enzyme involved in biotin degradation, was purified from a cell-free extract of a biotin-degrading bacterium, Mycoplana sp . No . 166 . The purification procedures comprised polyethyleneimine treatment, ammonium sulfate fractionation, and DEAE-Sepharose, Blue-Sepharose, Sephadex G-100, and FPLC (Mono Q HR 5/5) column chromatographies . The enzyme was found to be homogeneous on sodium dodecyl sulfate-polyacrylamide gel electrophoresis . The enzyme was a monomeric enzyme with a molecular weight and an isoelectric point of about 55,000 and 4.85, respectively . The purified enzyme catalyzed the stoichiometric conversion of biotin, ATP, and CoA into biotinyl-CoA, AMP, and PPi . Dethiobiotin and actithiazic acid, a synthetic biotin analog, were also effective as substrates . Other properties of the purified enzyme were also investigated.

J Bacteriol, 1986 Dec, 168(3), 1142 - 6
Photophosphorylation and oxidative phosphorylation in intact cells and chromatophores of an aerobic photosynthetic bacterium, Erythrobacter sp . strain OCh114; Okamura K et al.; Light-induced ATP synthesis was studied in intact cells and chromatophores of Erythrobacter sp . strain OCh114 . ATP synthesis was measured by both the pH method and the luciferin-luciferase luminescence method . The rate of ATP synthesis was moderate (a typical value of 0.65 mol of ATP per mol of bacteriochlorophyll per min), and synthesis was inhibited by antimycin A . ATP was synthesized under illumination only under aerobic conditions and not under anaerobic conditions . This characteristic was similar to that of other light-induced energy transduction processes in this bacterial species, such as oxidation of reaction center, oxidation of cytochrome c551, and translocation of H+, which were not observed under anaerobic conditions . This phenomenon was reconciled with the fact that the Erythrobacter sp . could not grow anaerobically even in the light . The characteristics of oxidative phosphorylation and ATP hydrolysis were also investigated . The respiratory ratio of chromatophores was 2.3 . Typical rates of oxidative phosphorylation by NADH and by succinate were 2.9 mol of ATP per mol of bacteriochlorophyll per min (P/O = 0.22) and 1.1 mol of ATP per mol of bacteriochlorophyll per min (P/O = 0.19), respectively . A typical rate of ATP hydrolysis was 0.25 mol of ATP per mol of bacteriochlorophyll per min in chromatophores . ATPase and adenylate kinase are also involved in the metabolism of adenine nucleotides in this bacterium.

CMAJ, 1986 Dec 1, 135(11), 1274 - 7
Legionnaires' disease caused by Legionella dumoffii in distilled water; Joly JR et al.; Five cases of Legionnaires' disease caused by Legionella dumoffii were identified within an 11-month period in a hospital in the Quebec City area . In four cases bacterial isolates were obtained from clinical specimens, and in one case seroconversion was demonstrated . All the patients had been admitted to hospital within 10 days before diagnosis . Two of the patients were immunosuppressed children . Only 1 of the 40 hot water samples from the hospital yielded L . dumoffii; however, 6 of 11 distilled water samples contained the bacterium . All the patients had been exposed to distilled water, four through respiratory therapy equipment and one through a room humidifier . Following the use of sterile distilled water in the apparatus, no further cases were identified . This is the first reported outbreak of Legionnaires' disease caused by L . dumoffii, and it is the first time that nosocomial legionellosis has been linked to contaminated distilled water in Canada.

J Oral Maxillofac Surg, 1986 Dec, 44(12), 1002 - 5
Submandibular space abscess due to Actinobacillus actinomycetemcomitans; Salman RA et al.; A submandibular space abscess is reported in which a pure culture of Actinobacillus actinomycetemcomitans was identified . The bacterium may often be overlooked as a pathogen due to its slow growth and its requirement for carbon dioxide for primary isolation . As A . actinomycetemcomitans is often resistant to commonly used antibiotics, proper management is based on careful utilization of microbiologic tests and clinical judgement . In this case prompt surgical drainage and appropriate antibiotic therapy resolved the abscess.

Microbiol Sci, 1986 Dec, 3(12), 376 - 8
Aerobic photosynthetic bacteria; Shiba T et al.; Erythrobacter species OCh 114 is a strictly aerobic bacterium containing bacteriochlorophyll a . Although its growth is dependent on heterotrophic nutrition, light enhances its growth yield and CO2-fixation activity . A new category--aerobic photosynthetic bacteria--is proposed for Erythrobacter species OCh 114.

J Biol Chem, 1986 Nov 15, 261(32), 15140 - 6
Three-dimensional structure of the iron-sulfur flavoprotein trimethylamine dehydrogenase at 2.4-A resolution; Lim LW et al.; The three-dimensional structure of trimethylamine dehydrogenase from the methylotrophic bacterium W3A1 has been determined to 2.4-A resolution . The enzyme is composed of two identical 83,000-dalton subunits, each of which is folded into three structural domains . The largest domain, at the NH2 terminus of the molecule, is folded as an eight-stranded parallel alpha/beta barrel . It contains the {4Fe-4S} and covalently bound FMN cofactors separated by about 4 A . The folding topology of the large domain and orientation of the FMN cofactor are very similar to those found in glycolate oxidase . The other two domains contain alpha/beta parallel beta sheet topologies with similar folding patterns . The topologies and spatial arrangements of these two domains are remarkably similar to the FAD- and NADPH-binding domains of glutathione reductase.

J Biol Chem, 1986 Nov 15, 261(32), 15102 - 5
Enzymes of vitamin B6 degradation . Purification and properties of pyridoxine 5'-dehydrogenase (oxidase); Jong YJ et al.; Isolation and identification of a soil bacterium, Arthrobacter Cr-7, that grows with pyridoxine as a sole source of carbon and nitrogen are described . An inducible pyridoxine 5'-dehydrogenase (oxidase) (EC 1.1.99.9) that catalyzes conversion of pyridoxine to isopyridoxal, Pyridoxine + X----isopyridoxal + XH2, the first step in utilization of pyridoxine as a growth substrate by this organism, was purified about 520-fold to homogeneity . The enzyme (Mr = 112,000) is a dimer of probably identical subunits and requires FAD (KD(app) = 0.24 microM) as coenzyme . It oxidizes only pyridoxine (Km = 0.18 mM) and a few related compounds (4-deoxypyridoxine, pyridoxamine, pyridoxal) that contain a free 5-CH2OH group and utilizes oxygen (Km = 0.28 mM), 2,6-dichloroindophenol, or quinones, but not NAD+ or NADP+, as hydrogen acceptors (X in reaction above) . With pyridoxine and oxygen as substrates, the enzyme has a broad pH optimum (from pH 7.0 to 8.3), a Vmax of 11.9 mumol X min-1 X mg-1, and a turnover number of 22 s-1 at 25 degrees C . The enzyme is strongly inhibited by sulfhydryl reagents . Except for its substrate specificity, these properties do not differ greatly from those of other flavin-dependent oxidases.

FEBS Lett, 1986 Nov 10, 208(1), 73 - 6
Structure of rubredoxin from the bacterium Desulfovibrio desulfuricans; Sieker LC et al.; The X-ray crystallographic structure of rubredoxin from Desulfovibrio desulfuricans strain 27774 is described . This molecule is 15% smaller than previously studied rubredoxins, lacking a seven-residue loop of chain but containing a histidine and a free-sulfhydryl cysteine . Except for solvent exposure of the single invariant tryptophan, no other major difference occurs in the molecule.

J Biol Chem, 1986 Nov 5, 261(31), 14593 - 9
Immunological comparison of the b and c1 cytochromes from bovine heart mitochondria and the photosynthetic bacterium Rhodopseudomonas sphaeroides R-26; Haley PE et al.; Antibodies against cytochromes b and c1 of bovine heart mitochondria and the photosynthetic bacterium, Rhodopseudomonas sphaeroides R-26, were raised in rabbits . The purified antibodies showed high titers against their respective antigens in enzyme-linked immunosorbent assays . Less than 15% cross-reactivity between the mitochondrial and bacterial cytochromes was detected . Although antibodies against mitochondrial cytochrome b did not inhibit the mitochondrial cytochrome b-c1 complex, a 70% inhibition was obtained when these antibodies were incubated with delipidated mitochondrial cytochrome b-c1 complex prior to reconstitution with phospholipids indicating that the catalytic site(s) of mitochondrial cytochrome b are masked by phospholipids . On the other hand, antibodies against bacterial cytochrome b showed significant inhibition of the intact bacterial cytochrome b-c1 complex, indicating that some of the catalytic site epitopes of bacterial cytochrome b are exposed to the hydrophilic environment . Similar to antibodies against mitochondrial cytochrome b, antibodies against bacterial cytochrome b inhibited 50% activity of the mitochondrial cytochrome b-c1 complex only when they were incubated with the delipidated mitochondrial cytochrome b-c1 complex prior to reconstitution with phospholipids, indicating that the common epitopes between the cytochromes b are masked by phospholipids . Antibodies against mitochondrial and bacterial cytochromes c1 completely inhibited their respective cytochrome b-c1 complexes but no cross-immunoinhibition was observed . However, when antibodies against bacterial cytochrome c1 were incubated with the delipidated mitochondrial cytochrome b-c1 complex before reconstitution with phospholipids, a 65% inhibition was observed, indicating that the common epitopes between the cytochromes c1 were also somewhat masked by phospholipids . Antibodies against mitochondrial cytochrome c1 inhibited 70% of the succinate oxidase activity in the intact mitochondria preparation, but no inhibition was observed in submitochondrial particles, indicating that some mitochondrial cytochrome c1 epitopes are exposed to the cytoplasmic side.

Eur J Biochem, 1986 Nov 3, 160(3), 557 - 61
Methylation in vivo of elongation factor EF-Tu at lysine-56 decreases the rate of tRNA-dependent GTP hydrolysis; Van Noort JM et al.; In this paper we show, that the in vivo methylation of the elongation factor Tu from Escherichia coli is correlated with the growth phase of the bacterium . Methylation occurs at one position only, i.e . Lys-56, and initially results in monomethylation during logarithmic growth . Upon entering the stationary phase of E . coli, monomethyllysine is gradually converted into dimethyllysine . We have undertaken an extensive comparison between the properties of the highly methylated EF-Tu and unmodified EF-Tu . No gross conformational differences, as measured by the rate of mild tryptic cleavage, were observed . The dissociation rates of the nucleotides GDP and GTP appear likewise to be unaffected by the methylation, just as is the stimulatory effect of the elongation factor Ts upon these rates . Whereas tRNA binding at the classical binding site of EF-Tu (site I) also appears not to be affected by the methylation of the protein, tRNA binding at site II is . Although the apparent affinity of tRNA for site II remains unaltered upon methylation of EF-Tu, the conformational effects of tRNA binding at this site become different . Both the GTPase activity of the protein and the reactivity of Cys-81 are significantly less stimulated by the tRNA when EF-Tu is methylated . A possible physiological implication of this phenomenon is discussed.

Arch Microbiol, 1986 Nov, 146(2), 111 - 4
Heliobacterium chlorum: cell organization and structure; Miller KR et al.; The basic cellular organization of Heliobacterium chlorum is described using the freeze-etching technique . Internal cell membranes have not been observed in most cells, leading to the conclusion that the photosynthetic apparatus of these organisms must be localized in the cell membrane of the bacterium . The two fracture faces of the cell membrane are markedly different . The cytoplasmic (PF) face is covered with densely packed particles averaging 8 nm in diameter, while the exoplasmic (EF) face contains far fewer particles, averaging approximately 10 nm in diameter . Although a few differentiated regions were noted within these fracture faces, the overall appearance of the cell membrane was remarkably uniform . The Heliobacterium chlorum cell wall is a strikingly regular structure, composed of repeating subunits arranged in a rectangular pattern at a spacing of 11 nm in either direction . We have isolated cell wall fragments by brief sonication in distilled water, and visualized the cell wall structure by negative staining as well as deep-etching.

Mikrobiologiia, 1986 Nov-Dec, 55(6), 1009 - 13
{Intracellular development of Escherichia coli bacteriophages after culturing the infected bacteria under conditions of anabiosis and hypothermia}; Tsutsaeva AA et al.; The intracellular growth of bacteriophages T3, T4 and phi X174 was studied in Escherichia coli cells frozen to -196 degrees C and cooled to 0 degree C at various intervals from the instant of phage infection . The processes of biosynthesis were delayed and the latent period was longer in the growth of cells frozen to -196 degrees C . The levels of RNA and protein biosynthesis as well as the yield of phages decreased when cells were frozen at a later stage of the phage growth . No changes were found in the intracellular growth processes of the phages during the subsequent cultivation of the bacterium when it was infected and then cooled to 0 degree C.

Mol Gen Mikrobiol Virusol, 1986 Nov, (11), 44 - 8
{Transposon-mediated integration of the RP1 plasmid into chromosomes of methylotrophic bacteria}; Naumov GN et al.; The homology region between the DNA of plasmid RP1ts::Tn601 and chromosome of the thermotolerant methylotrophic bacterium Methylobacterium sp . SKF240 has been constructed by transposon Tn601 translocation into the chromosome . The clones of Methylobacterium sp . SKF240 having integrated the plasmid RP1 into the chromosome have been obtained by conjugation on the basis of above mentioned genetic technique . The integration of plasmid RP1 into the chromosomal DNA of the methylotroph has been confirmed by the genetic and electrophoretic methods . Clones harbouring the integrated plasmid are able to transfer the chromosomal genes for methionine and isoleucine-valine synthesis to the recipient cells of P . aeruginosa PAO ML4262 by conjugation.

Biochem Biophys Res Commun, 1986 Oct 30, 140(2), 650 - 9
Induction of cytochrome P-450-dependent sulfonylurea metabolism in Streptomyces griseolus; Romesser JA et al.; Inducible cometabolism of several sulfonylurea herbicides by Streptomyces griseolus has been shown to occur by hydroxylation, O-dealkylation, or deesterification reactions . Only after growth of the bacterium in the presence of sulfonylurea did cell-free extracts exhibit NAD(P)H-dependent sulfonylurea metabolism . These extracts were shown to contain elevated levels of soluble cytochrome P-450 and exhibit sulfonylurea induced difference spectra consistent with binding of substrate to cytochrome(s) P-450 . These results establish the presence of an inducible cytochrome P-450-dependent sulfonylurea metabolizing system in S . griseolus.

J Mol Biol, 1986 Oct 5, 191(3), 579 - 80
Crystallization and preliminary X-ray diffraction study of ferrocytochrome c2 from Rhodopseudomonas viridis; Miki K et al.; Crystals of ferrocytochrome c2 from a non-sulphur purple photosynthetic bacterium, Rhodopseudomonas viridis, have been grown from ammonium sulphate solution at pH 8.5 by the sitting-drop vapour-diffusion procedure . The crystals belong to the trigonal system, space group P3(1)21 (or its enantiomorph P3(2)21) with unit-cell dimensions of a = b = 75.8 A and c = 40.1 A, and diffract to at least 2.0 A resolution . Assuming that an asymmetric unit contains one protein molecule (approx . 12,300 Mr), the solvent content of the crystal is approximately 54.5% (v/v).

J Biol Chem, 1986 Oct 5, 261(28), 12925 - 9
The gene crtI mediates the conversion of phytoene into colored carotenoids in Rhodopseudomonas capsulata; Giuliano G et al.; Carotenoids are membrane pigments present in all photosynthetic organisms, providing essential photoprotective functions . The first carotenoid formed in the pathway is phytoene, a colorless compound which is then converted into colored carotenoids by a series of dehydrogenation reactions . In the photosynthetic bacterium Rhodopseudomonas capsulata mutations that affect carotenoid biosynthesis before colored carotenoids are formed have a "blue-green" phenotype as opposed to the "red" of wild type cells . We have extracted carotenoids from several blue-green mutants and found that two strains (BPY69 and BPY102) accumulate phytoene and no colored carotenoids . These mutants failed to dehydrogenate phytoene in an in vitro assay . However, dehydrogenation of this compound can be achieved in vitro by adding a cell-free extract from another blue-green mutant blocked earlier in the pathway . Genetic complementation and deletion mapping indicate that the gene crtI is responsible for the conversion of phytoene into colored carotenoids in these mutants.

Dan Med Bull, 1986 Oct, 33(5), 257 - 65
Isolation and characterization of antigens from Treponema phagedenis biotype Reiter cross-reacting with Treponema pallidum; Petersen CS; The specific aims of the studies reviewed here were to design a rational purification strategy for Reiter treponeme antigens using combinations of different chromatographic principles, to isolate and characterize the Reiter treponemal antigens, especially the antigens labelled TR-b, TR-c, TR-dl, TR-d2, and TR-e cross-reacting with antigens in Treponema pallidum, to develop and evaluate the use of these purified antigens in syphilis diagnostic enzyme-linked immunosorbent assays (ELISA), to investigate whether Reiter treponeme antigens can induce protective immunity against experimental syphilis in rabbits . By combining anion exchange chromatography, gel filtration, agarose gel electrophoresis, hydrophobic interaction chromatography, and affinity chromatography on Iminodiacetic acid-Sepharose CL 4B and Lysine Sepharose 4B we were able to isolate seven different water soluble Reiter antigens from one single Reiter sonicate supernatant (I, II, III, IV, V, VI) . The applied chromatographic matrices were selected due to their efficiency for separation of the Reiter antigens in pilot experiments . In addition to the above mentioned Reiter antigens additional antigens labelled TR-o (V) and LPS (VI) were isolated . TR-b, TR-c, and TR-o were shown to be protein antigens (III, IV, V) . The TR-c antigen of the Reiter treponeme cross-reacted not only with an antigen in T . pallidum but also with an antigen common to a wide range of bacteria (IX) . The TR-d antigen composed of a ribonucleic acid component (TR-dl) (II) and a protein component (TR-d2) . The TR-e antigen represented the flagellum of the bacterium (I), and the LPS antigen was a pure lipopolysaccharide antigen (VI).(ABSTRACT TRUNCATED AT 250 WORDS)

J Bacteriol, 1986 Oct, 168(1), 167 - 72
Effect of uncoupler on assembly pathway for pigment-binding protein of bacterial photosynthetic membranes; Dierstein R et al.; The uncoupler carbonylcyanide m-chlorophenylhydrazone (CCCP) was used to investigate membrane protein assembly in the phototrophic bacterium Rhodobacter capsulatus . As found for Escherichia coli (T . Date, G . Zwizinsky, S . Ludmerer, and W . Wickner, Proc . Natl . Acad . Sci . 77:827-831, 1980) and mitochondrial proteins (N . Nelson and G . Schatz, Proc . Natl . Acad . Sci . USA 76:4365-4369, 1979), assembly across the bacterial photosynthetic membranes was sensitive to CCCP . At uncoupler concentrations which were sufficient to block the export of the periplasmic cytochrome c2 and an outer membrane protein, the integration of pigment-binding protein into the photosynthetic apparatus was abolished . The unassembled protein was detected on the inner surface of the intracytoplasmic membrane . After inactivation of CCCP, accumulated protein continued insertion into the membrane . The data suggest that after binding to the cytoplasmic face of the membrane, translocation of protein into a transmembrane orientation takes place, which is a prerequisite for the formation of a functional pigment-protein complex.

J Bacteriol, 1986 Oct, 168(1), 460 - 3
Development of a gene cloning system for the hydrogen-producing marine photosynthetic bacterium Rhodopseudomonas sp; Matsunaga T et al.; Seventy-six strains of marine photosynthetic bacteria were analyzed by agarose gel electrophoresis for plasmid DNA content . Among these strains, 12 carried two to four different plasmids with sizes ranging from 3.1 to 11.0 megadaltons . The marine photosynthetic bacterium Rhodopseudomonas sp . NKPB002106 had two plasmids, pRD06S and pRD06L . The smaller plasmid, pRD06S, had a molecular weight of 3.8 megadaltons and was cut at a single site by restriction endonucleases SalI, SmaI, PstI, XhoI, and BglII . Moreover, the marine photosynthetic bacterium Rhodopseudomonas sp . NKPB002106 containing plasmid pRD06 had a satisfactory growth rate (doubling time, 7.5 h), a hydrogen-producing rate of 0.96 mumol/mg (dry weight) of cells per h, and nitrogen fixation capability . Plasmid pRD06S, however, had neither drug resistance nor heavy-metal resistance, and its copy number was less than 10 . Therefore, a recombinant plasmid consisting of pRD06S and Escherichia coli cloning vector pUC13 was constructed and cloned in E . coli . The recombinant plasmid was transformed into Rhodopseudomonas sp . NKPB002106 . As a result, Rhodopseudomonas sp . NKPB002106 developed ampicillin resistance . Thus, a shuttle vector for gene transfer was constructed for marine photosynthetic bacteria.

J Bacteriol, 1986 Oct, 168(1), 49 - 54
Fatty acid degradation in Caulobacter crescentus; O'Connell M et al.; Fatty acid degradation was investigated in Caulobacter crescentus, a bacterium that exhibits membrane-mediated differentiation events . Two strains of C . crescentus were shown to utilize oleic acid as sole carbon source . Five enzymes of the fatty acid beta-oxidation pathway, acyl-coenzyme A (CoA) synthase, crotonase, thiolase, beta-hydroxyacyl-CoA dehydrogenase, and acyl-CoA dehydrogenase, were identified . The activities of these enzymes were significantly higher in C . crescentus than the fully induced levels observed in Escherichia coli . Growth in glucose or glucose plus oleic acid decreased fatty acid uptake and lowered the specific activity of the enzymes involved in beta-oxidation by 2- to 3-fold, in contrast to the 50-fold glucose repression found in E . coli . The mild glucose repression of the acyl-CoA synthase was reversed by exogenous dibutyryl cyclic AMP . Acyl-CoA synthase activity was shown to be the same in oleic acid-grown cells and in cells grown in the presence of succinate, a carbon source not affected by catabolite repression . Thus, fatty acid degradation by the beta-oxidation pathway is constitutive in C . crescentus and is only mildly affected by growth in the presence of glucose . Tn5 insertion mutants unable to form colonies when oleic acid was the sole carbon source were isolated . However, these mutants efficiently transported fatty acids and had beta-oxidation enzyme levels comparable with that of the wild type . Our inability to obtain fatty acid degradation mutants after a wide search, coupled with the high constitutive levels of the beta-oxidation enzymes, suggest that fatty acid turnover, as has proven to be the case fatty acid biosynthesis, might play an essential role in membrane biogenesis and cell cycle events in C . crescentus.

Infect Immun, 1986 Oct, 54(1), 37 - 42
Identification of the O-linked sialyloligosaccharides of glycophorin A as the erythrocyte receptors for S-fimbriated Escherichia coli; Parkkinen J et al.; The erythrocyte receptors for S-fimbriated Escherichia coli, which causes sepsis and meningitis in newborn infants, were investigated . Neuraminidase and trypsin treatments of erythrocytes abolished the hemagglutination ability of the bacteria . To identify the receptor glycoproteins, we separated erythrocyte membrane proteins by gel electrophoresis, blotted them to nitrocellulose, and incubated them with 125I-labeled bacteria . The only bacterium-binding bands identified corresponded to glycophorin A dimer and monomer, and the binding was abolished by neuraminidase treatment of the blot . Radiolabeled bacteria also bound to purified glycophorin A adsorbed to polyvinyl chloride microwells, and the binding was inhibited by other sialoglycoproteins and isolated sialyloligosaccharides containing the NeuAc alpha 2-3Gal sequence . Oligosaccharides which contain the NeuAc alpha 2-3Gal beta 1-3GalNAc and NeuAc alpha 2-3Gal beta 1-3(NeuAc alpha 2-6)GalNAc sequence and which are identical to the O-linked saccharides of glycophorin A were twofold more effective inhibitors of binding than were other oligosaccharides containing the NeuAc alpha 2-3Gal sequence . The replacement of sialic acid in asialoerythrocytes with a purified Gal beta 1-3GalNAc alpha 2-3 sialyltransferase, which forms the O-linked NeuAc alpha 2-3Gal beta 1-3GalNAc sequence in asialoglycophorins, restored bacterial hemagglutination . These results indicated that the major erythrocyte receptor for S-fimbriated E . coli is the NeuAc alpha 2-3Gal beta 1-3GalNAc sequence of the O-linked oligosaccharide chains of glycophorin A.

J Clin Microbiol, 1986 Sep, 24(3), 501 - 2
Endocarditis with Moraxella-like M-6 after cardiac catheterization; Perez RE; A patient developed bacteremia with CDC group M-6, a Moraxella-like bacterium, after a complicated heart catheterization . He was treated with tobramycin and ampicillin . The aortic valve was later replaced and did not show any signs of infection . The slow growth of M-6 can delay diagnosis and give misleading antibiotic susceptibility results . Penicillin is not always active against this organism.

J Bacteriol, 1986 Sep, 167(3), 1066 - 70
An ATP transport system in the intracellular bacterium, Bdellovibrio bacteriovorus 109J; Ruby EG et al.; The intracellularly growing bacterium Bdellovibrio bacteriovorus 109J transports intact ATP by a specific, energy-requiring process . ATP transport does not involve either an ADP-ATP or an AMP-ATP exchange mechanism but, instead, has characteristics of an active transport permease . Kinetically distinct systems for ATP transport are expressed by the two developmental stages of the bdellovibrio life cycle.

Biol Chem Hoppe Seyler, 1986 Sep, 367(9), 951 - 6
Purification and properties of an acetate kinase from Rhodopseudomonas palustris; Vigenschow H et al.; An acetate kinase from the photolithoautotrophically grown purple bacterium Rhodopseudomonas palustris was purified to apparent homogeneity by use of high resolving liquid chromatography steps . The monomeric enzyme was characterized by a relative molecular mass of 46,500 and an isoelectric point of 4.9 . There was an absolute requirement for divalent metal ions in the enzymatic reaction . Mg2+ and Mn2+ were the most activating cations . The acetate kinase used pyrimidine and purine nucleotides almost equally well as phosphoryl donors . The enzyme phosphorylated acetate, propionate, butyrate and isobutyrate . ATP and acetate revealed the lowest apparent Km values and seemed to act as the favoured substrates . The apparent Km values for ATP formation were considerable lower than those for the formation of acetyl phosphate . The activation energy Ea = 21 kJ/mol of the acetyl phosphate formation was determined by application of Arrhenius plots.

Dev Biol, 1986 Sep, 117(1), 252 - 66
A global analysis of developmentally regulated genes in Myxococcus xanthus; Kroos L et al.; Tn5 lac is a transposon that fuses the transcription of lacZ to exogenous promoters . We generated 2374 Tn5 lac insertion-containing strains of Myxococcus xanthus, a soil bacterium that undergoes multicellular development which culminates in the formation of spores . Thirty-six strains were identified that specifically increase beta-galactosidase expression at some particular time during development and these expression times range from minutes after starvation initiates development to 24 hr, when sporulation begins . Different maximum levels of beta-galactosidase expression were also observed and the maximum for many strains that begin beta-galactosidase expression late in development was observed only if spores were disrupted . Seven of the 36 strains display mild to severe defects in aggregation and/or sporulation, as did an additional five strains whose beta-galactosidase expression was not developmentally regulated . Restriction maps of the DNA adjacent to the Tn5 lac insertions that are developmentally regulated and/or cause developmental defects show that most of the 41 insertions are in different regions of the Myxococcus genome . The developmentally regulated Tn5 lac insertions described here provide a set of at least 29 new developmental markers for Myxococcus.

Eur J Biochem, 1986 Aug 15, 159(1), 189 - 94
13C NMR evidence for bacteriochlorophyll c formation by the C5 pathway in green sulfur bacterium, Prosthecochloris; Oh-hama T et al.; The 13C NMR spectra of the pheophorbide of bacteriochlorophyll c, formed in the presence of L-{1-13C}glutamate and {2-13C}glycine and {13C}bicarbonate in Prosthecochloris aestaurii, were analysed . The isotope in the glutamate was specifically incorporated into the eight carbon atoms in the tetrapyrrole macrocycle derived from the C-5 of 5-aminolevulinic acid, while no specific enrichment of these eight carbon atoms was observed in the spectrum of the pigment formed in the presence of {2-13C}glycine . These labelling patterns provide evidence for the operation of the C5 pathway of 5-aminolevulinic acid synthesis for bacteriochlorophyll c formation in the bacterium . The labelling of bacteriochlorophyll c by {13C}bicarbonate is consistent with its formation from 5-{1,4,5-13C}aminolevulinic acid formed by the C5 pathway from {1,2,5-13C}glutamic acid . It is proposed that this glutamate is the transamination product of 2-{1,2,5-13C}oxoglutaric acid, arising by carboxylation of {1,4-13C}succinyl-CoA with 13CO2 catalysed by 2-oxoglutaric acid synthase activity, and that the labelled succinyl-CoA is, in turn, derived by the fixation of 13CO2 by the reductive tricarboxylic acid cycle . The 13C chemical shifts of two sp2 quaternary carbons of bacteriopheophorbide c methyl ester (C-2 and C-4) were reassigned.

J Bacteriol, 1986 Aug, 167(2), 722 - 5
Putative signal peptide on the small subunit of the periplasmic hydrogenase from Desulfovibrio vulgaris; Prickril BC et al.; We sequenced the NH2 terminus of the large and small subunits of the periplasmic hydrogenase from the sulfate-reducing bacterium Desulfovibrio vulgaris (Hildenborough) and found that the small subunit lacks a region of 34 NH4-terminal amino acids coded by the gene for the small subunit (G . Voordouw and S . Brenner, Eur . J . Biochem . 148:515-520, 1985) . We suggest that this region constitutes a signal peptide based on comparison with known procaryotic signal peptides.

Cell Immunol, 1986 Aug, 101(1), 232 - 41
Dual effects of pertussis toxin on lymphoid cells in culture; Vistica BP et al.; Pertussis toxin (Ptx), a component of Bordetella pertussis, is responsible for many of the biological activities of this bacterium, including its potent adjuvant capacity . In attempt to better understand the Ptx activity on the immune response in vivo, we have examined the effect of Ptx on certain lymphoid cell responses in vitro which could be targets for the adjuvant activity of this molecule . Ptx was found to stimulate a variety of cell responses which include (a) increased production and release of interleukin-1 (IL-1) by human monocytes and murine macrophages; (b) co-mitogenesis, in combination with IL-1, in cultures of murine thymocytes; (c) mitogenesis in cultures of various peripheral lymphocytes; (d) increased production of IL-2 in cultures of human blood lymphocytes and rodent splenocytes; and (e) elevated release of IL-3 in cultures of murine spleen cells . In addition to its stimulatory effects, however, Ptx was found to inhibit responses of both mononuclear phagocytes and lymphocytes to other stimuli . Most activities of Ptx in vitro were achieved at the optimal concentration range of 1-10 micrograms/ml, which is 100-1000 times higher than that showing adjuvant effects in vivo . Possible explanations for the dual effect of Ptx and for the discrepancy in doses optimal for the effects in vivo and in vitro are discussed.

J Bacteriol, 1986 Aug, 167(2), 604 - 10
Expression of cellulase genes in Rhodobacter capsulatus by use of plasmid expression vectors; Johnson JA et al.; Broad-host-range plasmid vectors were constructed for expression of heterologous genes in the photosynthetic bacterium Rhodobacter capsulatus . These plasmids utilize an RK2-derived replicon for maintenance and conjugative transfer and the R . capsulatus rxcA promoter to obtain transcription of genes within appropriately positioned DNA fragments . The expression vectors were used to obtain synthesis of endoglucanase and exoglucanase in R . capsulatus from cellulase genes present on exogenously derived DNA fragments . The cellulase genes were expressed either by use of their native translation initiation signals or by in-frame fusion with the rxcA B870 beta gene translation initiation signals to form a hybrid protein . The level of cellulase gene expression was found to be modulated in response to the extent of aeration of plasmid host cultures.

Nature, 1986 Jul 31-Aug 6, 322(6078), 481 - 3
Primary sequence of a dimeric bacterial haemoglobin from Vitreoscilla; Wakabayashi S et al.; Vitreoscilla, a filamentous bacterium in the Beggiatoa family, synthesizes a soluble haem-protein which has two identical subunits of relative molecular mass 15,775 and two b haems per molecule . It is synthesized in relatively large quantities when the organism, a strict aerobe, is grown under hypoxic conditions . It forms a relatively stable oxygenated form which is spectrally similar to oxymyoglobin (oxyHb) and oxyhaemoglobin (oxyHb) . The amino acid sequence of this protein has been determined and aligned to fit the helical regions of several animal and plant globins . This alignment is consistent with its being a structural homologue of the eucaryotic haemoglobins although it diverged from the others in the N-terminal region and may lack an A-helix . It showed the maximum sequence homology (24%) with lupin leghaemoglobin (Lb) . Vitreoscilla Hb is the first bacterial haemoglobin to be sequenced . It may function to enable the organism to survive in oxygen-limited environments by acting as an oxygen storage-trap or to facilitate oxygen diffusion.

Scand J Haematol, 1986 Jul, 37(1), 18 - 24
Effect of C3 depletion on the genesis of thrombocytopenia induced in rats by Erysipelothrix rhusiopathiae; Nakato H et al.; The role of complement in the pathogenesis of marked thrombocytopenia induced in rats by Erysipelothrix rhusiopathiae (E . rhusiopathiae) was examined . In cobra venom factor (CoF)-treated rats thrombocytopenia was not induced by the bacterium . The content of 5-hydroxytryptamine (5-HT) in platelets was decreased significantly after inoculation only in untreated rats . E . rhusiopathiae could bind C3 and generate platelet-bacteria aggregation when incubated in the plasma diluted with veronal-buffered saline containing calcium and magnesium (VBS++) or gelatin-VBS containing magnesium and ethyleneglycol tetra-acetic acid (GVB-Mg-EGTA), but not when incubated in GVB-ethylenediamine tetra-acetic acid (GVB-EDTA) diluted plasma or in CoF-treated or anti rat C3-treated plasma . When platelets were preincubated with activated zymosan, no bacteria could bind to platelets . From the results, we speculate that the alternative complement pathway, activated by E . rhusiopathiae, appears to mediate the formation of platelet-bacterial aggregations that may accelerate the removal of platelets from circulating blood.

J Lipid Res, 1986 Jul, 27(7), 724 - 30
A diphytanyl ether analog of phosphatidylserine from a methanogenic bacterium, Methanobrevibacter arboriphilus; Morii H et al.; Several ninhydrin-positive lipids were found in methanogenic bacteria and the structure of one of them, designated as PNL2 from Methanobrevibacter arboriphilus, was identified as a diphytanyl ether analog of phosphatidylserine . The chromatographic behavior of the lipid on thin-layer plates and on a DEAE-cellulose column was identical to the ester form of phosphatidylserine . The infrared spectra showed the presence of amino, carboxyl, ether, and phosphate groups, and the absence of an ester linkage . The hydrophobic portion of the lipid was identified as diphytanyl glycerol diether on the basis of the mass spectrum of the acetolysis product and gas-liquid chromatography of the iodinated alkyl chain prepared by hydroiodic acid cleavage of PNL2 . The fast atom bombardment-ionization and field desorption mass spectrum provided a molecular weight of 819 and several fragment ions consistent with the proposed structure . Hydrofluoric acid hydrolysis resulted in water-soluble products including serine, phosphoserine, and ammonia, which accounted for 95% of hydrolyzed PNL2 . The lipid product of the hydrolysis was mainly the diether form of phosphatidic acid . This is the first report on the structural characterization of an amino-containing phospholipid in archaebacteria . Amino lipids have been found in many other methanogenic bacteria.

J Periodontol, 1986 Jul, 57(7), 441 - 6
Mucosal induction of systemic T cell tolerance by Fusobacterium nucleatum; Keys JM et al.; The present study was undertaken to determine if mucosal presentation of the periodontopathic bacterium Fusobacterium nucleatum could induce systemic tolerance . Two separate protocols of mucosal priming were carried out . In the first, mice were gastrically intubated on 2 consecutive days; this was repeated 5 days later . In the second protocol, mice were similarly primed but received another priming dose after a further 7 days . Positive control mice were similarly primed with sheep red blood cells (SRBC) while negative control animals were sham-primed with saline . Following mucosal priming, mice were systemically sensitized with the respective antigen and then subsequently challenged in the left hind footpad . The right footpad was challenged with saline and served as a negative control . Serum antibody levels were measured using enzyme-linked immunoabsorbent assay (ELISA) and haemagglutination assays . Mucosal priming with F . nucleatum was found to suppress the local delayed type hypersensitivity reaction as determined by footpad measurements . Sham-priming did not suppress the local response . On the other hand, the levels of serum antibodies were not influenced by mucosal priming . These results suggest that under the experimental conditions used, mucosal presentation of F . nucleatum can induce a degree of split tolerance in which T cell responses are suppressed while B cell responses remain intact . The implication of this finding to human periodontal disease is yet to be determined.

Arch Biochem Biophys, 1986 Jul, 248(1), 62 - 70
Role of the small subunit of ribulose-1,5-bisphosphate carboxylase/oxygenase in the activation process; Incharoensakdi A et al.; The large (A) and small (B) subunits of ribulose-1,5-bisphosphate carboxylase/oxygenase (EC 4.1.1.39) from the cyanobacterium Aphanothece halophytica and from the purple sulfur photosynthetic bacterium Chromatium vinosum (strain D) were separated by sucrose density gradient centrifugation at low ionic strength and alkaline pH (9.3), respectively . It was found that subunit B enhances the extent of activation by CO2 and Mg2+ at equilibrium of the two homologous enzymes consisting of Aphanothece large subunit and its own small subunit (AaBa) and the Chromatium large subunit and its own small subunit (AcBc) . The extent of activation induced by saturating amounts of subunit B was larger with AcBc than AaBa, amounting to 3.7- and 1.8-fold of that by each catalytic core alone, respectively . Subunit B stimulated both the extent of activation at equilibrium and catalysis in a parallel and simultaneous manner with respect to the concentration of B in both homologous enzymes . These results suggest that subunit B interacts with both activation and catalytic sites simultaneously . On the other hand, Chromatium subunit B only slightly stimulated the extent of activation in the hybrid enzyme AaBc . The role of subunit B in enhancing the extent of activation at equilibrium can be substituted by the effect exerted by 6-phosphogluconate . Both homologous enzymes AaBa and AcBc showed a faster deactivation rate when the enzyme was activated in the absence of subunit B . The mechanism by which subunit B promotes activation seems to involve its effect on stabilizing the activated enzyme molecule . From studies on the Km for substrate CO2 in the hybrid enzyme AaBc a major involvement of subunit B in influencing Km (CO2) seems unlikely.

J Bacteriol, 1986 Jul, 167(1), 89 - 95
Immunocytochemical ultrastructural analysis of chromatophore membrane formation in Rhodospirillum rubrum; Crook SM et al.; An immunocytochemical ultrastructural study of Rhodospirillum rubrum cultured under semiaerobic conditions was conducted to correlate the localization of functional components with membrane formation . R . rubrum is a facultatively phototrophic organism . Under reduced oxygen, this bacterium forms an intracytoplasmic chromatophore membrane that is the site of the photosynthetic apparatus . Immunogold techniques were used to localize intracellular protein antigens associated with the photosynthetic apparatus . Antibody, demonstrated by immunoblotting to be specific for the reaction center and light-harvesting photochemical components, was conjugated to colloidal gold particles and used for direct immunolabeling of fixed, sectioned specimens . Membrane invaginations appeared by 4 h after transition to induction conditions, and mature chromatophore membrane was abundant by 22 h . The occurrence of chromatophore membrane was correlated with bacteriochlorophyll a content and the density of the immunolabel . In uninduced (aerobic) cells and those obtained from cultures 0.5 h posttransition, the immunogold preferentially labeled the peripheral area of the cell . In contrast, in cells obtained after 22 h of induction, the central region of the cell was preferentially immunolabeled . These findings provided immunocytochemical evidence supporting the hypothesis that the chromatophore membrane is formed by invagination of the cytoplasmic membrane.

J Clin Microbiol, 1986 Jul, 24(1), 121 - 5
Monoclonal antibodies for serotyping the P fimbriae of uropathogenic Escherichia coli; de Ree JM et al.; Monoclonal antibodies (MAbs) against seven serologically different P fimbriae (F7(1), F7(2), F8, F9, F11, F12, and F13) of uropathogenic Escherichia coli were tested for their ability to detect the P fimbriae on wild-type strains . In a plate agglutination test the MABs could detect the fimbriae on strains which expressed cloned fimbriae but not on wild-type strains . In a coagglutination test and in a whole-bacterium enzyme-linked immunosorbent assay the MAbs recognized the fimbriae on strains with cloned fimbriae and on wild-type strains . However, the coagglutination test has some disadvantages: only immunoglobulin G MAbs can be used, and the results cannot be read in an objective way . From these results, we concluded that the whole-bacterium enzyme-linked immunosorbent assay is the most convenient method for the determination of P fimbriae on wild-type E . coli strains . With this fast and easy method it is possible to do epidemiological studies on the distribution of P fimbriae among clinical isolates of uropathogenic E . coli and to extend the O:K:H serotype with the F serotype.

J Gen Microbiol, 1986 Jun, 132 ( Pt 6), 1631 - 9
Host modification of the adherence properties of Chlamydia trachomatis; Bose SK et al.; The adherence of Chlamydia trachomatis LGV440(L1) to human HeLa 229 and mouse McCoy cells was stimulated by the lectin wheat germ agglutinin (WGA) and inhibited by the sugars N-acetyl-D-glucosamine, N-acetyl-D-galactosamine and chitobiose, but only when the chlamydiae had been passaged several times in HeLa cells . After passage in McCoy cells, the lectin and the sugars elicited little response . The non-LGV serovar UW-31(K), however, differed from LGV440(L1) in that, regardless of passage, the lectin and sugar effects were observed only in HeLa cells . Affinity chromatography on WGA-agarose confirmed that HeLa-grown LGV440(L1) bound to a significantly greater extent relative to McCoy-grown chlamydiae . In addition, participation of heterogeneous chlamydial ligands was suggested by the observation that the adherence of heated (60 degrees C, 5 min) UW-31(K) to HeLa cells at 37 degrees C was not inhibited at all, but at 5 degrees C, the adherence rate was greatly reduced, indicating the participation of heat-stable as well as heat-labile ligands . These data are interpreted to indicate that the passage history of C . trachomatis results in the acquisition of altered surface components that participate in the initial interaction of the bacterium with the host.

Clin Chem, 1986 Jun, 32(6), 987 - 91
A rapid enzymatic procedure for "fingerprinting" bacteria by using pattern recognition of two-dimensional fluorescence data; Pau CP et al.; We describe a rapid fluorescence technique for bacterial "fingerprinting," based on the differences in enzyme content and activity of various bacteria . Bacterial cells are incubated with a mixture of carefully chosen fluorogenic enzyme substrates to produce fluorophores with unique emission and excitation properties . The resulting two-dimensional fluorescence spectrum of the product mixture produces a pattern characteristic of the bacterium . A Fourier-transform-based pattern recognition algorithm is used for spectral matching and for differentiating visually similar spectra . This sensitive technique is potentially applicable to differentiation and identification of bacteria in clinical laboratories.

Biochem J, 1986 Jun 1, 236(2), 579 - 84
Substrate specificity and regulation of the maize (Zea mays) leaf ADP: protein phosphotransferase catalysing phosphorylation/inactivation of pyruvate, orthophosphate dikinase; Budde RJ et al.; The protein substrate specificity of the maize (Zea mays) leaf ADP: protein phosphotransferase (regulatory protein, RP) was studied in terms of its relative ability to inactivate/phosphorylate pyruvate, orthophosphate dikinase from Zea mays and the non-sulphur purple photosynthetic bacterium Rhodospirillum rubrum . The dimeric bacterial dikinase was inactivated by the maize leaf RP via phosphorylation, with a stoichiometry of approximately 1 mol of phosphate incorporated/mol of 92.7-kDa protomer . Inactivation required both ADP and ATP, with ADP being the specific donor for regulatory phosphorylation . The requirements for inactivation/phosphorylation in this heterologous system were identical with those previously established for the tetrameric maize leaf dikinase . The ADP-dependent maize leaf RP did not phosphorylate alternative protein substrates such as casein or phosvitin, and its activity was not affected by cyclic nucleotides, Ca2+ or calmodulin . The regulation of the maize leaf ADP: protein phosphotransferase was studied in terms of changes in adenylate energy charge and pyruvate concentration . The change in adenylate energy charge necessary to substantially inhibit phosphorylation of maize leaf dikinase was not suggestive of it being a physiological modulator of phosphotransferase activity . Pyruvate was a potent competitive inhibitor of regulatory phosphorylation (Ki = 80 microM), consistent with its interaction with the catalytic phosphorylated intermediate of dikinase, the true protein substrate for ADP-dependent phosphorylation/inactivation.

Infect Immun, 1986 Jun, 52(3), 840 - 5
A 160-kilodalton epithelial cell surface glycoprotein recognized by plant lectins that inhibit the adherence of Actinomyces naeslundii; Brennan MJ et al.; The adherence of Actinomyces naeslundii to human epithelial (KB) cells is mediated by the interaction of a fimbrial lectin on this oral bacterium with epithelial cell receptors exposed by sialidase . The D-galactose- and N-acetyl-D-galactosamine-reactive plant lectins from peanut and from Bauhinia purpurea inhibit this interaction . This report describes the partial purification and characterization of a 160-kilodalton (kDa) cell surface glycoprotein which is the principal receptor for these lectins . Radioiodinated lectins detected a band of 160 kDa on sialidase-treated Western blots of epithelial cell extracts but did not detect bands on nontreated filters . However, wheat germ agglutinin was reactive with the 160-kDa band on filters that were not treated with sialidase, suggesting that this lectin recognizes the sialic acid residues of this molecule . The 160-kDa component was partially purified from n-octylglucoside extracts of the epithelial cells by wheat germ agglutinin affinity chromatography . This molecule was metabolically labeled with D-{14C}glucosamine and labeled at the cell surface by lactoperoxidase-catalyzed iodination or periodate oxidation followed by sodium borotritide reduction . Incubation of epithelial cells with sialidase before extraction resulted in the loss of the 160-kDa band and the appearance of a band at 200 kDa which was directly reactive with 125I-labeled peanut agglutinin . These results indicate that the 160-kDa glycoprotein on the surface of the epithelial cell serves as a receptor for the agglutinins from the peanut and B . purpurea and presumably the fimbrial lectin of actinomyces.

Mikrobiologiia, 1986 May-Jun, 55(3), 391 - 4
{Selective method of isolating mutants sensitive to ultraviolet radiation from a culture of Rhodopseudomonas sphaeroides}; Rodina NE et al.; The method of penicillin selection used after UV-irradiation (lambda = 254 nm) allows one to select UV-sensitive mutants (uvs-mutants) of the phototrophous bacterium Rhodopseudomonas sphaeroides induced by nitrosomethylurea with an effectiveness greater by an order of magnitude . Over 30% of the uvs-mutants obtained using this method had an elevated sensitivity not only to far-UV (F-UV, lambda = 254 nm) but also to near-UV (N-UV, lambda greater than 280 nm) UV-irradiation . No correlation was found in the degree of sensitivity to F-UV and N-UV-irradiation of the uvs-mutants . Mutants highly sensitive to the lethal action of N-UV were isolated.

Zentralbl Bakteriol Mikrobiol Hyg {A}, 1986 May, 261(3), 255 - 65
Commemoration of the publication 100 years ago of the papers by Dr . Th . Escherich in which are described for the first time the organisms that bear his name; Bettelheim KA; The centenary of the publication by Dr . Th . Escherich of his papers on the colonization of the intestines of neonates by bacteria is commemorated . His papers are reviewed and discussed from the point of view of current knowledge . The organisms described by him as Bacterium coli commune and now known as Escherichia coli are particularly discussed and their role as enteropathogens assessed . Current work on these organisms is contrasted with studies on them over the last 100 years.

J Pediatr, 1986 May, 108(5 Pt 2), 866 - 70
Antibiotic therapy in cystic fibrosis: evaluation of clinical trials; Smith AL; Evaluation of antibiotic efficacy for infections in previously well individuals is based on eradication of the bacterium and resolution of the signs and symptoms of inflammation . In patients with cystic fibrosis, these criteria are less applicable: systemic signs of inflammation (fever, leukocytosis, and increased erythrocyte sedimentation rate) are variably present, and bacteria are present in the lower respiratory tract after clinical improvement . Administration of a variety of antibiotics produces resolution of subjective signs and symptoms and improvement in pulmonary function tests . Because of the cost of therapy, the need to evaluate new and potentially toxic antibiotics, and the desire to provide optimum care, the evaluation of therapy needs to be objective . Controlled studies evaluating efficacy in a blinded fashion and assessing lung function and resolution of local pulmonary inflammation may provide reliable data on antibiotic effectiveness in CF.

Infect Immun, 1986 May, 52(2), 617 - 9
Monoclonal antibodies reactive with K1-encapsulated Escherichia coli lipopolysaccharide are opsonic and protect mice against lethal challenge; Kaufman BM et al.; Seven murine monoclonal antibodies (MAbs) directed against O-side-chain determinants of the K1-encapsulated Bortolussi strain of Escherichia coli (O18:K1:H7) were evaluated for their in vitro and in vivo activities . All the MAbs reacted well in Western blots against E . coli O18 lipopolysaccharide antigens . Two MAbs of the immunoglobulin G (IgG) class promoted in vitro opsonophagocytosis and protected mice lethally challenged with bacteria . Two IgM MAbs showed partial protection, although they had no in vitro opsonic activity, and the remaining three IgM MAbs showed no apparent functional activities . Monoclonal IgG antibodies against bacterial lipopolysaccharide can be opsonic and protective in spite of the presence of the K1 capsule on the bacterium.

J Biochem (Tokyo), 1986 May, 99(5), 1425 - 31
3 beta-Hydroxysteroid dehydrogenase of Ruminococcus sp . from human intestinal bacteria; Akao T et al.; Ruminococcus sp . PO1-3 obtained from human intestinal flora is able to reduce dehydrocholate as well as 3-ketoglycyrrhetinate . From this bacterium dehydrocholate- and 3-ketoglycyrrhetinate-reducing activities were purified one thousand-fold together with 3-ketocholanate-reducing and 3-beta-hydroxyglycyrrhetinate (glycyrrhetic acid) oxidizing activities by means of Matrex Red A, Sephadex G-200 and Octyl-Sepharose column chromatography . The purified enzyme catalyzed the reduction of dehydrocholic acid to 3 beta-hydroxy-7,12-diketocholanic acid and of 3-ketocholanic acid to 3 beta-hydroxycholanic acid . Studies on substrate specificity revealed that the enzyme had absolute specificity for the beta-configuration of a hydroxyl group at the 3 position of bile acid and steroids having no double bond in the A/B ring . This enzyme was neither beta-hydroxysteroid dehydrogenase {EC 1.1.1.51} nor 3 beta-hydroxy-delta 5-steroid dehydrogenase {EC 1.1.1.145}, but a novel type of enzyme, defined as 3 beta-hydroxysteroid dehydrogenase.

J Bacteriol, 1986 May, 166(2), 513 - 8
Reversible regulation of the nitrogenase iron protein from Rhodospirillum rubrum by ADP-ribosylation in vitro; Lowery RG et al.; Nitrogenase activity in the photosynthetic bacterium Rhodospirillum rubrum is reversibly regulated by interconversion of the Fe protein between a modified and an unmodified form . Since the discovery of the activation process in 1976, investigators have been unable to demonstrate the inactivation (modification) reaction in vitro . In this study, NAD-dependent modification and concomitant inactivation of the Fe protein were demonstrated in crude extracts of R . rubrum . Activation of the in vitro-modified Fe protein by activating enzyme and structural similarity between the in vivo and in vitro modifications are presented as evidence that the in vitro modification is the physiologically relevant ADP-ribosylation reaction . Using a partially purified preparation, we showed that the inactivating enzyme activity is stimulated by divalent metal ions and ADP, that O2-denatured Fe protein will not serve as a substrate, and that dithionite inhibits the modification reaction.

Biochemistry, 1986 Apr 22, 25(8), 2276 - 87
Iron-depleted reaction centers from Rhodopseudomonas sphaeroides R-26.1: characterization and reconstitution with Fe2+, Mn2+, Co2+, Ni2+, Cu2+, and Zn2+; Debus RJ et al.; Reaction centers (RCs) from the photosynthetic bacterium Rhodopseudomonas sphaeroides R-26.1 were depleted of Fe by a simple procedure involving reversible dissociation of the H subunit . The resulting intact Fe-depleted RCs contained 0.1-0.2 Fe per RC as determined from atomic absorption and electron paramagnetic resonance (EPR) spectroscopy . Fe-depleted RCs that have no metal ion occupying the Fe site differed from native RCs in the following respects: (1) the rate of electron transfer from QA- to QB exhibited nonexponential kinetics with the majority of RCs having a rate constant slower by only a factor of approximately 2, (2) the efficiency of light-induced charge separation (DQA----D+QA-) produced by a saturating flash decreased to 63%, and (3) QA appeared readily reducible to QA2- . Various divalent metal ions were subsequently incorporated into the Fe site . The electron transfer characteristics of Fe-depleted RCs reconstituted with Fe2+, Mn2+, Co2+, Ni2+, Cu2+, and Zn2+ were essentially the same as those of native RCs . These results demonstrate that neither Fe2+ nor any divalent metal ion is required for rapid electron transfer from QA- to QB . However, the presence of a metal ion in the Fe site is necessary to establish the characteristic, native, electron-transfer properties of QA . The lack of a dominant role of Fe2+ or other divalent metals in the observed rate of electron transfer from QA- to QB suggests that a rate-limiting step (for example, a protonation event or a light-induced structural change) precedes electron transfer.

J Mol Biol, 1986 Apr 5, 188(3), 443 - 54
Structure and X-ray amino acid sequence of a bacteriochlorophyll a protein from Prosthecochloris aestuarii refined at 1.9 A resolution; Tronrud DE et al.; The structure of the water-soluble bacteriochlorophyll a protein (Bchl protein) from the green photosynthetic bacterium Prosthecochloris aestuarii has been refined at 1.9 A resolution to a crystallographic residual of 18.9% . The refinement was carried out without knowledge of the amino acid sequence and has led to an "X-ray sequence" . The structure consists of seven Bchl molecules enclosed within a protein "bag" and the refinement supports the general conformation of the molecule described previously . The refinement also supports the previous suggestion that the ligands to the seven Bchl magnesiums are, respectively, five histidines, a carbonyl oxygen from the polypeptide backbone of the protein, and a bound water molecule . The conformations of the seven Bchl head-groups are described in detail . In two cases the magnesium atoms are approximately 0.48 A "below" the plane of the conjugated macrocycle while in the other five cases the atoms are, on average, 0.48 A "above" the plane . The acetyl ring substituents are more-or-less coplanar with the dihydrophorbin macrocycle, consistent with a previous resonance Raman study . The conjugated atoms in each of the seven macrocycles have significant departures from strict planarity . These deviations are similar for Bchls 1, 2 and 3 (class I) and are also similar for Bchls 4, 5, 6 and 7 (class II) . Ethylchlorophillide also belongs to class II . The out-of-plane deformations for the class I and class II bacteriochlorophylls appear to correspond to two distinct modes of bending or curvature of the dihydrophorbin macrocycle.

Arch Biochem Biophys, 1986 Apr, 246(1), 192 - 8
13C-NMR evidence of bacteriochlorophyll a formation by the C5 pathway in Chromatium; Oh-hama T et al.; The 13C-NMR spectra of bacteriochlorophyll a formed in the presence of L-{1-13C}glutamate and {2-13C}glycine in Chromatium vinosum strain D were analyzed . The isotope in the glutamate was specifically incorporated into eight carbon atoms in the tetrapyrrole macrocycle derived from the C-5 of 5-aminolevulinic acid (ALA), and the 13C in glycine was incorporated into the methyl carbon of the methoxycarbonyl group attached to the isocyclic ring of bacteriochlorophyll a . These labeling patterns provide evidence for the exclusive operation of the C5 pathway in ALA biosynthesis in the bacterium . The 13C chemical shifts of two quaternary carbons (C-9 and C-16) of bacteriochlorophyll a were reassigned in the present study.

Appl Environ Microbiol, 1986 Apr, 51(4), 753 - 60
Effect of lectin on nodulation by wild-type Bradyrhizobium japonicum and a nodulation-defective mutant; Halverson LJ et al.; The nodulation characteristics of wild-type Bradyrhizobium japonicum USDA 110 and mutant strain HS111 were examined . Mutant strain HS111 exhibits a delayed-nodulation phenotype, a result of its inability to initiate successful nodulation promptly following inoculation of the soybean root . Previously, we showed that the defect in initiation of infection leading to subsequent nodulation which is found in HS111 can be phenotypically reversed by pretreatment with soybean root exudate or soybean seed lectin . This effect is not seen after pretreatment with root exudates and lectins obtained from other plant species . Treatment of strain HS111 with as little as 10 soybean seed lectin molecules per bacterium (3.3 X 10 (-12) M) resulted in enhancement of nodule formation . Pretreatment of wild-type B . japonicum USDA 110 with soybean root exudate or seed lectin increased nodule numbers twofold on 6-week-old plants . Wild-type strain USDA 110 cells inoculated at 10(4) cells per seedling exhibited a delay in initiation of infection leading to subsequent nodulation . Wild-type cells pretreated in soybean root exudates or seed lectin did not exhibit a delay in nodulation at this cell concentration . Mutant strain HS111 pretreated in seed lectin for 0 or 1 h, followed by washing with the hapten D-galactose to remove the lectin, exhibited a delay in initiation of nodulation . Phenotypic reversal of the delayed-nodulation phenotype exhibited by strain HS111 was seen if incubation was continued for an additional 71 h in plant nutrient solution following 1 h of lectin pretreatment . Reversal of the delayed-nodulation phenotype of HS111 through lectin pretreatment was prevented by chloramphenicol or rifampin.(ABSTRACT TRUNCATED AT 250 WORDS)

J Bacteriol, 1986 Apr, 166(1), 59 - 65
Mechanism of delta pH maintenance in active and inactive cells of an obligately acidophilic bacterium; Goulbourne E Jr et al.; The acidophilic bacterium PW2 possessed a delta pH of ca . 1.9 and a delta psi of 0 mV, corresponding to a proton motive force (delta p) of--114 mV . Protonophore-treated cells possessed little delta p but a delta pH of ca . 1.5, as measured by salicylic acid distribution or pH measurement of cell lysates . Starving PW2 cells continued to possess a delta pH of ca . 1.7, but exhibited converse changes in delta psi and delta p, with the former rising to +80 to +100 mV and the latter dropping essentially to 0; progressive loss of respiration, cellular ATP, and culture viability accompanied these changes . Thus, the protonophore-treated or starving PW2 cells attained an H+ electrochemical equilibrium . Net H+ influx resulting from declining respiration probably accounted for the increased delta psi in these cells; indeed, when respiration was progressively inhibited in active cells, there was increasing transient H+ influx and a proportional increase in delta psi . This transient H+ influx was sufficient to lethally acidify the cytoplasm, but for a buffering capacity of 85 nmol of H+/mg of protein per pH unit . Thus, the linkage of the transient H+ influx with the rise in the delta psi and the cytoplasmic buffering capacity play central roles in acidophilism, and it is conceivable that the same impermeant cellular macromolecule(s) accounts for both . If so, the delta psi would be a Donnan potential that in active cells is offset by energy-dependent H+ extrusion.

Biochem Biophys Res Commun, 1986 Mar 28, 135(3), 1000 - 7
Isolation of fumarate reductase from Desulfovibrio multispirans, a sulfate reducing bacterium; He SH et al.; Fumarate reductase was isolated and purified 100-fold to homogeneity from Desulfovibrio multispirans, a new species of sulfate-reducing bacteria . The enzyme contained 1 mol of non-covalently bound FAD and four subunits with Mr 45,000, 32,000, 30,000 and 27,000 . EPR spectroscopy showed the existence of two iron-sulfur clusters . The absorption spectrum showed a broad region of high absorbance from 450 nm to 300 nm with a protein peak at 278 nm . The ratio of A278:A400 was 2.60 . The specific activity was 110 mumoles H2/mg of protein . The Km for fumarate was 2.5 mM . The activation energy was 8.7 kcal/mol . Electron transport from H2 to fumarate in intact cells was inhibited by 2-heptyl-4-hydroxy-quinoline-N-oxide, a quinone inhibitor, indicating the participation of quinone (probably menaquinone) in fumarate reduction.

J Biol Chem, 1986 Mar 15, 261(8), 3607 - 15
The complete amino acid sequence of a bacteriochlorophyll a-protein from Prosthecochloris aestuarii; Daurat-Larroque ST et al.; The amino acid sequence of a bacteriochlorophyll a-protein from the green photosynthetic bacterium Prosthecochloris aestuarii strain 2K has been determined . Use was made of a tentative sequence deduced from a 2.8-A electron density map of the protein to help locate sequenced peptides . The polypeptide chain consists of 366 amino acids . The identities of 5 amino acids that ligand to the magnesium atoms of 5 of the 7 bacteriochlorophyll molecules present in each subunit of the trimeric complex have been confirmed as histidines.

J Biol Chem, 1986 Mar 15, 261(8), 3616 - 9
Methylamine dehydrogenase and cytochrome c552 from the bacterium W3A1; Chandrasekar R et al.; We describe a two-step purification of the methoxatin-containing enzyme methylamine dehydrogenase from crude extracts of the bacterium W3A1, and a longer purification of cytochrome c552 from the same organism . Some of the kinetic properties of the dehydrogenase are presented, together with the demonstration that c552 is an electron acceptor for this enzyme . Cytochrome c552 is the only hemeprotein we observed in the visible spectrum of intact W3A1 cells that were grown under the same culture conditions used for the protein purifications . Addition of methylamine to whole cells causes an increase in the rate of O2 uptake together with an abrupt reduction of c552 . We propose that, in vivo, the electrons from the amine reach the hemeprotein through the dehydrogenase.

J Clin Microbiol, 1986 Mar, 23(3), 650 - 1
Wound colonization by Ewingella americana; Bear N et al.; Ewingella americana was recovered from a wound on the left leg of a 46-year-old male after a compound fracture of the tibia and fibula . Compared with the reported characteristics of 44 American strains, this strain was shown to belong to biogroup 1 . The isolation of this bacterium in South Africa confirms its wide geographical distribution in clinical specimens . Colonization was not associated with clinical deterioration.

J Bacteriol, 1986 Mar, 165(3), 825 - 30
Cloning in Escherichia coli K-12 of a Na+-dependent transport system from a marine bacterium; MacLeod PR et al.; The transport of D-alanine by Escherichia coli K-12 neither requires nor is stimulated by Na+ . The transport of D-alanine by the marine bacterium Alteromonas haloplanktis 214 requires Na+ specifically . Mutants of E . coli which were unable to transport D-alanine were isolated by enrichment for D-cycloserine resistance . One of the mutants was transformed with a gene bank of A . haloplanktis chromosomal DNA . Two transformants, E . coli RM1(pPM1) and E . coli RM1(pPM2) were able to transport D-alanine by a Na+-dependent mechanism . Li+ and K+ were unable to replace Na+ . Both transformants contained chimeric plasmids with inserts which hybridized with A . haloplanktis but not E . coli chromosomal DNA or each other . Despite the lack of homology between the inserts, Na+-dependent D-alanine transport in the two transformants could not be distinguished either by kinetic studies or by differences in the capacity of various amino acids to compete for D-alanine uptake.

Mutat Res, 1986 Mar, 173(3), 163 - 8
Enhancement by cysteamine of N-methyl-N-nitrosourea mutagenesis in E . coli; Naslund M et al.; Cysteamine (MEA) is comutagenic to methylnitrosourea (MNU) in E . coli AB 1157 but not in the nonadaptable mutant derivative ada-6 of that strain . The comutagenic action of MEA was eliminated by cysteine at low concentrations, which also lowered mutation frequencies in AB1157 but not in ada-6 . In model experiments it was shown that cysteine counteracted the inhibition by MEA of beta-galactosidase induction in both bacterium strains . The comutagenic action of MEA is interpreted as being due to an inhibition of induction of methyltransferase during treatment with MNU.

Infect Immun, 1986 Mar, 51(3), 776 - 83
Collaboration of bovine T lymphocytes and macrophages in T-lymphocyte response to Brucella abortus; Splitter GA et al.; Brucella abortus-induced bovine macrophage-T-lymphocyte collaboration was studied as a prerequisite for the eventual clearance of this infectious organism . Esterase-positive, peripheral blood monocytes functioned as an adherent antigen-presenting cell population . A dual requirement for expression of bacterial antigens in combination with self major histocompatibility complex class II products was required by adherent cells for the activation of T lymphocytes . Comparison of antigen-presenting cell populations that were either trypsinized or nontrypsinized following B . abortus ingestion substantiated the need for phagocytosis and antigen processing . A monoclonal antibody (H4) directed against major histocompatibility complex class II determinants was able to block or, with complement, to abrogate T-lymphocyte responses . Measurement of both proliferation and interleukin 2 production via {3H}thymidine incorporation confirmed specific activation of an enriched T-lymphocyte population . These results indicate that in vivo-primed T lymphocytes of peripheral blood origin recognize phagocytized bacterial components of the facultative intracellular bacterium B . abortus and may contribute to the removal of the bacteria . Furthermore, bovine peripheral blood-adherent cells function as classic antigen-presenting cells, which suggests that macrophages are capable of processing this bacteria . Therefore, any lymphocyte-mediated dysfunction attributable to B . abortus most likely occurs at some point in the cascade of immune events following initial macrophage-T-lymphocyte collaboration.

J Biol Chem, 1986 Feb 25, 261(6), 2799 - 803
Phenylalanyl-tRNA synthetase from chloroplasts of a higher plant (Phaseolus vulgaris) . Purification and comparison of its structural, functional, and immunological properties with those of the enzymes from the corresponding cytoplasm, the cyanobacterium Anacystis nidulans, and the photosynthetic green sulfur bacterium Chlorobium limicola; Rauhut R et al.; Chloroplastic phenylalanyl-tRNA synthetase from bean leaves is purified under optimal protective conditions over 4,900-fold . Its apparent molecular weight is 78,000, as determined by gel filtration, with a dimeric subunit structure of alpha beta (alpha = 33,000 and beta = 42,000), as determined by sodium dodecyl sulfate gel electrophoresis . This indicates a drastic size reduction of 40% for each subunit compared to the corresponding cytoplasmic enzyme and a unique quaternary structure . Heterologous aminoacylation and substrate properties of ATP analogs indicate substantial differences in the topographies of the substrate binding domains of these two heterotopic intracellular plant enzymes . No common antigenic determinants with the bean cytoplasmic enzyme were detected by polyclonal antibodies against the chloroplastic enzyme . The same negative result applies to the immunological comparison with the partially purified enzymes from the cyanobacterium Anacystis nidulans and the photosynthetic green sulfur bacterium Chlorobium limicola that both have a molecular weight of 260,000.

Life Sci, 1986 Feb 24, 38(8), 677 - 85
The influence of Bordetella pertussis and its constituents on the beta-adrenergic receptor in the guinea pig respiratory system; van Heuven-Nolsen D et al.; In the present study, the effect of vaccination of guinea pigs with Bordetella pertussis was investigated, 4 days after treatment, on the cholinergic and beta-adrenergic receptor function in isolated tracheal spirals and the number of beta-adrenoceptor binding sites in guinea pig lung . It was found that B . pertussis caused an impairment in the beta-adrenoceptor function and a decrease in its number . Similar results were obtained with endotoxin . Leucocytosis promoting factor, however, was ineffective . These results indicate that endotoxin is the constituent responsible for the beta-adrenoceptor blocking effects of the bacterium . Also the combined whole cell diphtheria, B . pertussis and tetanus toxoid vaccine induced a beta-adrenoceptor blockade; the acellular vaccine was less effective . The results obtained with the B . pertussis vaccines are discussed in relation to the possible side-effects that sometimes occur after immunization of infants.

Appl Environ Microbiol, 1986 Feb, 51(2), 429 - 31
Isolation of an antigenically unique methanogen from human feces; Misawa H et al.; A methanogenic bacterium with the morphological and physiological properties of the genus Methanobrevibacter was isolated from the feces of a Japanese man who excreted methane in his breath . Indirect immunofluorescence staining revealed that the isolate had an antigenicity unrelated to that of any known members of the genus Methanobrevibacter.

Clin Immunol Immunopathol, 1986 Feb, 38(2), 150 - 60
Chlamydia trachomatis (L2 serovar) binds to distinct subpopulations of human peripheral blood leukocytes; Bard J et al.; We have previously shown that infants with pneumonitis caused by Chlamydia trachomatis, an obligate intracellular bacterium, possess increased percentages of B lymphocytes but not T lymphocytes in their peripheral blood . It was then demonstrated that chlamydiae induce proliferation in vitro of human peripheral blood B lymphocytes and, in the presence of T cells, differentiation of B cells to immunoglobulin-secreting cells . In this study, we show that C . trachomatis (L2 serovar) binds preferentially to 50% of human B lymphocytes from peripheral blood but only to a small percentage, if any, of T cells . Both monocytes and granulocytes bind and ingest chlamydiae . Despite chlamydial binding to B cells and ingestion by monocytes, no uptake by B cells and limited growth (fewer than 0.5% inclusion-containing cells) in monocytes occur . There is a dramatic decrease in the percentage of cells associated with the bacteria after culture . These results are the first demonstration of binding of C . trachomatis (L2 serovar) to lymphocytes and represent a direct step toward correlating physical interactions between bacteria and lymphocytes with specific immunostimulatory activities in vitro.

J Biochem (Tokyo), 1986 Feb, 99(2), 423 - 35
A novel FAD-protein that allows effective reduction of methyl viologen by NADH (NADH-methyl viologen reductase) from photosynthetic bacterium, Rhodospirillum rubrum: purification and characterization; Saeki K et al.; It was found that the cytoplasm of light-grown cells of Rhodospirillum rubrum could catalyze the reduction of methyl viologen (MV) (Em, 7 = -0.44 V) by NADH and NADPH . In the present study, the enzyme capable of catalyzing MV reduction by NADH (NADH-MV reductase) was purified 1,500-fold from an extract of cells with a yield of 4.4% . The purification procedure comprised (NH4)2SO4 fractionation, and chromatographies on Sepharose CL-6B, DEAE-Sepharose CL-6B, phenyl-Sepharose CL-4B, Blue-Cellulofine, and TSK-Gel G3000SW . Two NADPH-MV reductases were separated during the purification . The NADH-MV reductase obtained was nearly homogeneous, as judged on polyacrylamide gel electrophoresis both in the presence and absence of sodium dodecyl sulfate . The enzyme has a molecular weight of 220,000 and an isoelectric point of 4.8; it is composed of four subunits with a molecular weight of 57,000, and is bound with about 1 mol FAD/mol subunit . The activity is optimum at pH 8 . The Km values for NADH and MV are 115 microM and 1.3 mM, respectively, with a molecular activity of 13,000 min-1 . The activity was stimulated 2.4-fold in the presence of 20-100 mM ammonium ions . The enzyme also catalyzed the reduction of benzyl viologen, methylene blue and 2,6-dichlorophenol-indophenol (Em, 7 = -0.36, +0.011, and +0.217 V, respectively) at comparable rates . The ratios of the activity with NADH to that with NADPH were 80, 133, 41, and 5.5 with MV, benzyl viologen, methylene blue and 2,6-dichlorophenolindophenol, respectively . The enzyme was significantly stable in the presence of both 5mM 2-mercaptoethanol and 20% (w/v) glycerol . The activity was not appreciably influenced by the presence of 2 M urea, although the reagent caused dissociation to the subunits.

J Biochem (Tokyo), 1986 Feb, 99(2), 605 - 6
Crystallographic study of cytochrome c553 from Desulfovibrio vulgaris Miyazaki; Nakagawa A et al.; Cytochrome c553 from the sulfate-reducing bacterium, Desulfovibrio vulgaris Miyazaki, has been crystallized . The combination of microdialysis and vapor diffusion allowed successful crystallization . The crystals were of good quality, and useful data were obtained that extended to the nominal resolution of 1.3 A . The space group is P4(3)2(1)2 with cell dimensions of a = b = 42.7 A, c = 103.4 A . More than twenty heavy-atom reagents were screened with the isomorphous replacement technique, and only the mersalyl derivative could be used for the phase determination . The single isomorphous replacement method combined with the anomalous scattering effect of the Hg-atom in mersalyl and the Fe-atom of the heme group was used for the phase determination.

J Bacteriol, 1986 Feb, 165(2), 483 - 8
Partial purification and characterization of pyruvate, orthophosphate dikinase from Rhodospirillum rubrum; Ernst SM et al.; We confirmed an earlier report (B . B . Buchanan, J . Bacteriol . 119:1066-1068, 1974) that the nonsulfur purple photosynthetic bacterium Rhodospirillum rubrum contains pyruvate, orthophosphate dikinase (EC 2.7.9.1) activity that is absolutely dependent upon all three substrates by performing enzyme assays in both the forward (phosphoenolpyruvate formation) and reverse (ATP formation) directions . Of the various carbon sources tested, photoheterotrophic growth on DL-lactate plus bicarbonate proved to be best for the production of dikinase activity units . A four-step protocol, which included batch DEAE-cellulose processing, ammonium sulfate fractionation, and chromatography on hydroxylapatite and Blue A Dyematrex gels, was devised for partially purifying the enzyme from such cells . The protein was purified about 80-fold to an apparent electrophoretic purity of about 60% and a final specific activity of 3.6 U/mg of protein, with about a 35% overall recovery of activity units . Estimations of native and monomeric relative molecular weights by sucrose density gradient centrifugation, high-pressure liquid chromatography-based size exclusion chromatography, denaturing electrophoresis, and immunoblotting suggested that the holoenzyme was most likely a homodimer of 92.7-kilodalton subunits . The results are compared with related previous data on the nonphotosynthetic bacterial dikinase and the C4 mesophyll chloroplast enzyme.

J Mol Biol, 1986 Jan 20, 187(2), 305 - 8
Phosphorylation of an Escherichia coli protein at tyrosine; Cortay JC et al.; The analysis of protein phosphorylation in the bacterium Escherichia coli showed that, while most phosphoproteins are modified at serine and/or threonine residues, one of them is modified exclusively at tyrosine . This particular protein which has a molecular weight of 54,500 and a pHi value of 5.6 is found associated with the membrane/ribosome fraction of the cell.

Biochem J, 1986 Jan 15, 233(2), 547 - 52
The purification and some equilibrium properties of the nitrite reductase of the bacterium Wolinella succinogenes; Blackmore R et al.; The bacterium Wolinella succinogenes produces a nitrite reductase enzyme that can be purified to homogeneity in high yield by a combination of detergent extraction, hydroxyapatite chromatography and Mr fractionation . Nitrite reductase activity is found to be present in both a high- and a low-Mr fraction . The high-Mr fraction has been shown to consist of the low-Mr nitrite reductase enzyme associated with a hydrophobic 'binding protein' . The amino acid composition for both proteins is reported . The nitrite reductase enzyme shows spectral characteristics indicative of the presence of c-type haem groups . Measurements at 610 nm indicate the presence of some high-spin haem groups at neutral pH . This haem subgroup undergoes a pH-linked high-spin - low-spin transition at alkaline pH . Approximately two of the six haem groups present within the enzyme bind CO with low affinity (KD = 0.4 mM) . The enzyme also shows a range of redox activities with various inorganic reagents . The enzyme has been shown to exhibit dithionite reductase, oxygen reductase and CO2 reductase activities.

Eur J Biochem, 1986 Jan 15, 154(2), 383 - 6
Purification, crystallization and preliminary X-ray investigation of quinoprotein methylamine dehydrogenase from Thiobacillus versutus; Vellieux FM et al.; The enzyme methylamine dehydrogenase or primary-amine:(acceptor) oxidoreductase (deaminating) (EC 1.4.99.3) was purified from the bacterium Thiobacillus versutus to homogeneity, as judged by polyacrylamide gel electrophoresis . The native enzyme has a Mr of 123 500 and contains four subunits arranged in a alpha 2 beta 2 configuration, the light and heavy subunits having a Mr of 12900 and 47500 respectively . The isoelectric point is 3.9 . The purified enzyme was crystallized from 37--42% saturated ammonium sulphate in 0.1 M sodium acetate buffer, pH 5.0 . The space group is P3(1)21 or P3(2)21, with one alpha 2 beta 2 molecule in the asymmetric unit . The cell dimensions are: a = b = 13.01 nm; c = 10.40 nm . The X-ray diffraction pattern extends to at least 0.25-nm resolution.

Biochem J, 1986 Jan 15, 233(2), 333 - 7
The amino acid sequence of cytochrome c-555 from the methane-oxidizing bacterium Methylococcus capsulatus; Ambler RP et al.; The amino acid sequence of the cytochrome c-555 from the obligate methanotroph Methylococcus capsulatus strain Bath (N.C.I.B . 11132) was determined . It is a single polypeptide chain of 96 residues, binding a haem group through the cysteine residues at positions 19 and 22, and the only methionine residue is a position 59 . The sequence does not closely resemble that of any other cytochrome c that has yet been characterized . Detailed evidence for the amino acid sequence of the protein has been deposited as Supplementary Publication SUP 50131 (12 pages) at the British Library Lending Division, Boston Spa, West Yorkshire LS23 7BQ, U.K., from whom copies are available on prepayment.

J Mol Biol, 1986 Jan 5, 187(1), 141 - 3
New crystal forms of ribulose-1,5-bisphosphate carboxylase/oxygenase from Rhodospirillum rubrum; Schneider G et al.; Three crystal forms of the dimeric form of the enzyme ribulose-1,5-bisphosphate carboxylase from the photosynthetic bacterium Rhodospirillum rubrum have been obtained from the gene product expressed in Escherichia coli . Form A crystals formed from the quaternary complex comprising enzyme-activator carbamate-Mg2+-2'-carboxyarabinitol-1,5-bisphosphate are shown here to be devoid of ligands . In contrast, crystals of the quaternary complex formed with the hexadecameric L8S8 enzyme from spinach contain both the activator carbamate and 2'-carboxyarabinitol-1,5-bisphosphate . Form B crystals of the R . rubrum enzyme are monoclinic, space group P2(1) with cell dimensions a = 65.5 A, b = 70.6 A, c = 104.1 A and beta = 92.1 degrees, with two subunits per asymmetric unit . Rotation function calculations show a non-crystallographic 2-fold axis perpendicular to the monoclinic b-axis . Form C crystals are orthorhombic (space group P2(1)2(1)2(1)) with cell dimensions a = 79.4 A, b = 100.1 A and c = 131.0 A . The monoclinic crystal form diffracts to at least 2.0 A resolution on a conventional X-ray source.

Biol Chem Hoppe Seyler, 1986 Jan, 367(1), 33 - 8
The cell surface glycoprotein of Halobacterium halobium . Physico-chemical characterization in the absence and presence of salt; Hecht K et al.; The cell surface glycoprotein of Halobacterium halobium is soluble in dilute buffer at neutral pH . At low counterion concentrations, the protein is monomeric (Ms,D = 209 kDa) and exhibits the characteristics of a highly charged polyelectrolyte . Evidence obtained from intrinsic fluorescence and far-UV circular dichroism shows that the monomer at low salt loses both its native conformation and its inherent tendency to form high molecular mass assemblies . In 4M NaCl, 25 mM KCl, and in the presence of divalent ions (greater than or equal to 50mM Mg2+ or Ca2+), association to well-defined assemblies of up to approximately 4 X 10(6) Da occurs . At low Mg2+ concentration and in the presence of Ba2+, a wide size-distribution of aggregates is observed . The assembly pattern of the protein may be correlated with salt-dependent alterations in the morphology of the bacterium.

J Bacteriol, 1986 Jan, 165(1), 215 - 8
Biosynthesis of the 7-methylated pterin of methanopterin; White RH; The incorporation of {15N}glycine and {U-methyl-2H}methionine into methanopterin by growing cells of a methanogenic bacterium was measured to establish the biosynthetic route of the methylated pterin in the structure . The tetrahydromethanopterin produced by the cells was oxidatively cleaved to produce 7-methylpterin, and the amount of label incorporated into this pterin was measured by gas chromatography-mass spectrometry of the ditrimethylsilyl derivative of this compound . Approximately 27% of the 7-methylpterin and the guanine present in the cell was derived from the fed {15N}glycine . {U-methyl-2H}methionine was incorporated with the initial retention of all three deuteriums . These results are consistent with the biosynthesis of the pterin of methanopterin originating from GTP and its 7-methyl group arising from the methyl group of methionine.

Ann Biol Clin (Paris), 1986, 44(4), 373 - 9
{Capnocytophaga infections . Apropos of 8 cases}; Arlet G et al.; Eight Capnocytophaga infections are described: bacteremia in immunodepressed patients (three cases), endocarditis (one case), pneumopathy (one case), buccal infection (two cases) and endometritis during use of an intrauterine contraceptive device (one case) . The role of this bacterium in infections presented by immunodepressed patients is discussed in terms of literature data . Identification of the genus posed no problems . Species diagnosis is considered in terms of the use of conventional biochemical tests and the API ZYM collection.

Growth, 1986 Spring, 50(1), 32 - 40
Mycobacterium avium-intracellulare infection and immunoblastic sarcoma in a fatal case of AIDS; Cantwell AR Jr; A pleomorphic bacterium exhibiting both acid-fast rod forms and non-acid-fast coccal forms, and identified as Mycobacterium avium-intracellulare was cultured from a facial lesion diagnosed as immunoblastic sarcoma . The patient was a 36 year-old homosexual man who died of the acquired immune deficiency syndrome (AIDS) . In addition, the patient had pre-existing cutaneous lesions of Kaposi's sarcoma (KS), and was treated for probable but never proven, Pneumocystis carinii pneumonia (PCP) . Variably acid-fast coccoid forms, and extremely rare acid-fast rods were demonstrated within the microscopic sections of the immunoblastic sarcoma . Similar-staining coccoid forms were also observed within the microscopic sections of the pre-existing KS tumors, and within the lung biopsy material showing inflammation suggestive of PCP . These findings, along with previously reported findings of similar bacterial forms in vivo in other cases of KS and AIDS, again suggest that variably acid-fast bacteria may play a role in the development of malignant tumors and inflammatory lung disease, which frequently occur in homosexual men with AIDS.

Nauchnye Doki Vyss Shkoly Biol Nauki, 1986, (11), 33 - 6
{Competitive interaction of serotonin and the dye acridine orange with DNA}; Strakhovskaia MG et al.; The interaction of serotonin and acridine orange dye with DNA isolated from bacterium Escherichia coli and the yeast Candida utilis has been analysed by spectrofluorimetric method . Using data on competitive binding to DNA of serotonin and acridine orange, known as DNA intercalator, a conclusion concerning the formation of intercalated complex between serotonin and DNA has been made . It is shown that for yeast DNA the constant of intercalated binding of serotonin is 3,5-fold smaller than for the bacterial one.

Int Rev Exp Pathol, 1986, 28, 45 - 78
The immunobiology of leprosy; Kaplan G et al.; Leprosy, a chronic infectious disease of man, is caused by the obligate intracellular bacterium M . leprae . Infection with M . leprae affects the peripheral nerves and the dermis, causing an accumulation of macrophages and other immune cells at the infected sites . Host resistance to the bacterium determines the extent of local inflammatory reactions and its resulting damage to the affected tissues . In lepromatous disease little if any cellular immunity develops . Bacterial multiplication is uncontrolled and M . leprae disseminate throughout most of the dermis . In tuberculoid disease, marked cellular immunity is observed and bacterial growth and dissemination are controlled . The depression of cellular immunity in lepromatous patients is not fully understood . Since M . leprae cannot be grown in vitro, and a suitable animal model has not yet been developed, the study of host immunity to the pathogen is limited primarily to investigations of the cutaneous lesions of patients and to in vitro responses of the peripheral blood leukocytes to M . leprae . While the blood monocytes of leprosy patients appear to be activated normally by lymphokines, T cell proliferation and production of lymphokines in response to M . leprae are impaired in lepromatous patients . Attempts to restore responsiveness in cells from these patients have been unsuccessful in our hands . The addition of exogenous IL-2 to leukocyte cultures does not appear to restore responsiveness to M . leprae in cells from nonresponsive patients . Rather, some enhancement, often not antigen specific, is observed in cells from patients with a preexisting response . Similarly, depletion of monocytes does not restore responsiveness to M . leprae in nonresponder patients, but a nonspecific enhancement of proliferation is observed in monocyte-free cultures from patients that do respond to M . leprae . Thus, the defect in lepromatous nonresponder patients does not result from a simple lack of IL-2 production or suppression by monocytes and/or their products . Possibly, there is a low level or lack of M . leprae-responsive T cells in the circulation of these patients . Attempts to overcome the defect in immunity of patients with lepromatous leprosy by immunoprophylaxis and immunotherapy are being investigated . This approach has become of major importance since the development of widespread drug resistance to Dapsone as well as to the other chemotherapeutic agents used to control leprosy.

Nauchnye Doki Vyss Shkoly Biol Nauki, 1986, (7), 98 - 102
{Rhodopseudomonas sphaeroides mutants defective in nitrogen fixation}; Frolova VD et al.; Mutants of phototrophic bacterium Rhodopseudomonas sphaeroides deficient in nitrogen fixation and unable to utilize alanine, proline, arganine and glutamic acid as nitrogen sources have been obtained as a result of nitrosomethylurea mutagenesis . The majority of the nif-mutants have no nitrogenase activity and aminotransferase activity of glutamine synthetase during their growth in glutamine containing medium is sharply lowered . The specific activity of glutamate synthase and alanine dehydrogenase in the mutants does not differ from that of the wild type strain . One of the mutants (NF-42) has higher glutamine synthetase activity in comparison with the wild type strain . The pleiotropic character of the changes obtained in the nif-mutants shows that the loss of nitrogen fixation ability is due to defects in regulation system of nitrogen metabolism.

Mikrobiologiia, 1986 Jan-Feb, 55(1), 152 - 4
{Bioluminescent method of assessing the toxicity of colored substances in waste waters from celluose sulfate manufacture}; Novikova LN et al.; The aim of this work was to study the applicability of a bioluminescent technique for assaying the toxicity of solutions containing lignin sulfate and coloured compounds isolated from the sewage of the sulfate-cellulose industry after biological purification . Solutions of the studied compounds (pH 7.0) quenched the bioluminescence of the luminescent bacterium Beneckea harveyi in proportion to their colour index and their content of phenol hydroxyls . This biotest based on quenching the luminescence of bacteria under the action of a toxic agent is rapid and highly reproducible . Therefore, it can be used for assaying the toxicity of sulfate-cellulose industry sewage containing hardly oxidizible coloured compounds . The toxic action of sewage can be predicted basing in the found dependence between the colour index of solutions containing coloured compounds and the intensity of bacterial bioluminescence.

J Bacteriol, 1986 Jan, 165(1), 1 - 5
Ferrochelatase from Rhodopseudomonas sphaeroides: substrate specificity and role of sulfhydryl and arginyl residues; Dailey HA et al.; Purified ferrochelatase (protoheme ferrolyase; EC 4.99.1.1) from the bacterium Rhodopseudomonas sphaeroides was examined to determine the roles of cationic and sulfhydryl residues in substrate binding . Reaction of the enzyme sulfhydryl residues with N-ethylmaleimide or monobromobimane resulted in a rapid loss of enzyme activity . Ferrous iron, but not porphyrin substrate, had a protective effect against inactivation by these two reagents . Quantitation with 3H-labeled N-ethylmaleimide revealed that inactivation required one to two sulfhydryl groups to be modified . Modification of arginyl residues with either 2,3-butanedione or camphorquinone 10-sulfonate resulted in a loss of ferrochelatase activity . A kinetic analysis of the modified enzyme showed that the Km for ferrous iron was not altered but that the Km for the porphyrin substrate was increased . These data suggested that arginyl residues may be involved in porphyrin binding, possibly via charge pair interactions between the arginyl residue and the anionic porphyrin propionate side chain . Modification of lysyl residues had no effect on enzyme activity . We also examined the ability of bacterial ferrochelatase to use various 2,4-disubstituted porphyrins as substrates . We found that 2,4-bis-acetal- and 2,4-disulfonate deuteroporphyrins were effective substrates for the purified bacterial enzyme and that N-methylprotoporphyrin was an effective inhibitor of the enzyme . Our data for the ferrochelatase of R . sphaeroides are compared with previously published data for the eucaryotic enzyme.

Fam Pract Res J, 1986 Winter, 6(2), 67 - 71
Recurrent Legionnaires' disease: a case report; Skrobot BJ et al.; In 1979, an isolated case of legionnaires' disease in a 46 year old Caucasian male Ohio physician was reported . Diagnosis was later confirmed by a fourfold increase in indirect immunofluorescent antibody titer level . Recovery began rapidly after the administration of erythromycin therapy and appeared to be complete . The following year the same patient suffered an apparent reinfection, once again realizing prompt and total recovery upon receiving erythromycin therapy . Although not commonly reported, the possibility of reinfection with the Legionella bacterium is a reality . The source of human innoculation need not necessarily be a common water supply or large cooling system reservoir (as was previously thought) . Erythromycin continues to be widely regarded as the treatment of choice for infections with the Legionella bacterium even though this case demonstrates that it does not prevent reinfection.

Antonie Van Leeuwenhoek, 1986, 52(5), 387 - 92
The apparent oxidation of NADH by whole cells of the methylotrophic bacterium Methylophilus methylotrophus . A cautionary tale; Patchett RA et al.; Previous reports that whole cells of Methylophilus methylotrophus oxidase exogenous NADH have been investigated . Essentially identical rates of oxygen consumption were observed following the addition of methanol or NADH to whole cells . Both activities were inhibited by EDTA and hydroxylamine, but not by HQNO, and exhibited similar pH optima . Analyses of the reaction stoichiometry with NADH as substrate showed that the expected amount of oxygen was consumed, but also revealed acidification (instead of alkalinisation) and no oxidation of NADH . Further studies showed that commercial NADH is contaminated with ethanol which is oxidised to acetic acid by the low specificity methanol oxidase system present in this organism . The oxidation of exogenous NADH by whole cells of M . methylotrophus reported previously is therefore spurious.

Biochimie, 1986 Jan, 68(1), 97 - 101
Redox properties and active center of phototrophic bacteria hydrogenases; Zorin NA; It is shown that the activity of phototrophic bacteria hydrogenases depends on the redox potential (Eh) of the medium . Hydrogenase from the purple sulfur bacterium Thiocapsa roseopersicina strain BBS reversibly activates H2 at Eh less than -290 mV (pH 7.0) . When Eh is increased from -290 to -170 mV, the enzyme is converted into an inactive form which is accompanied by one-electron oxidation of its Fe-S cluster . In contrast, the hydrogenases of the purple nonsulfur bacterium Rhodobacter capsulatus B10 and the green sulfur bacterium Chlorobium limicola forma thiosulfatophilum exhibit maximum activity at Eh greater than -300 mV, favourable only for H2 uptake . When Eh decreases the activities of these enzymes drop dramatically; this accounts for their unidirectional effect directed mainly towards H2 uptake . Such dependence on Eh of activity of hydrogenases from these bacteria correlates with their physiological function in the metabolism of phototrophic bacteria, i.e . with the catalysis of the H2 uptake reaction . Hydrogenases from purple bacteria contain nickel and a single Fe-S cluster . Metal chelators do not affect the activity of these enzymes, which indicates that iron and nickel are tightly bound to the apoprotein . Sulfhydryl compounds irreversibly inactivate T . roseopersicina hydrogenase by 30-40% in the presence of sulfide . Acetylene and carbon monoxide are reversible inhibitors of the enzyme . EPR and inhibitory analysis indicate a direct interaction of H2 with the nickel ion in the active center of the T . roseopersicina hydrogenase.

Arch Biochem Biophys, 1986 Jan, 244(1), 285 - 91
Cyanide- and carbon monoxide-resistant mutants of Vitreoscilla: altered cytochromes and respiratory properties; Tamura-Lis W et al.; Two respiratory mutants of the aerobic bacterium, Vitreoscilla, have been studied: a CO-resistant mutant that can grow in 50% CO-50% oxygen, and a cyanide-resistant mutant that can grow in 1 mM KCN . Wild-type cells are unable to grow under either condition . This report presents evidence that the resistance of the CO mutant is due to an altered membrane-bound cytochrome o {cytochrome o(m)}, and that of the cyanide mutant is due to the presence of an increased amount of cytochrome d, which has a lower affinity for cyanide than cytochrome o(m) . The evidence was obtained from spectral studies on the three types of intact cells as well as enzymatic and ligand-binding techniques on the cytoplasmic cytochromes o{cytochrome o(s)} and the respiring membrane vesicles isolated from these cells . Carbon monoxide difference spectra of intact cells revealed a 5-nm shift in an absorption maximum of a CO-binding pigment in the CO mutant relative to that of the wild type . The formation of oxygenated cytochrome o(s) and its conversion to the reduced form when the cells became anaerobic due to cellular respiration were inhibited when 1 mM KCN was added to a cell suspension of wild-type cells; the cyanide mutant cells showed resistance to cyanide in this experiment . Cytochrome o(s) purified from all three cell types had identical physical, electron transferring, and ligand binding properties within experimental error . Respiring membrane vesicles isolated from the two mutants showed more resistance to inhibition by cyanide and carbon monoxide than those from the wild type . Carbon monoxide difference spectra of these membrane vesicles revealed that there was a fivefold increase in the amount of cytochrome d in the cyanide mutant relative to the wild type . A CO absorption band of the membrane-bound cytochrome o in the CO mutant membrane vesicles showed a 5-nm shift relative to that of the wild type.

Arch Biochem Biophys, 1986 Jan, 244(1), 122 - 7
Functional characterization of the uncoupler-insensitive Na+ pump of the halotolerant bacterium, Ba1; Ken-Dror S et al.; Respiration initiates Na+ efflux from Na+-preloaded cells of the halotolerant bacterium, Ba1 . This efflux can take place against the concentration and electrochemical gradients . Since it is not inhibited by carbonylcyanide-p-trifluoromethoxyphenyl-hydrazone or N'N'-dicyclohexylcarbodiimide, it seems unlikely that either delta p (electrochemical potential difference of H+ across the membrane) generated by the primary proton pump or ATP play a role in the transduction of the energy supplied by electron transport . The electrogenic extrusion of Na+ causes passive counterflow of protons and/or simultaneous flux of permeant anions . In the absence of permeant anions the charge compensation attained by influx of protons is not complete . The membrane potential which persists in this case is inside negative and insensitive to uncoupler . The influx of protons builds up a delta pH of reversed sign (more acid inside), which is insensitive to uncoupler . The simultaneous efflux of Na+ and permeant anions diminishes the intracellular salt content and, as a corollary, causes volume contraction . Thus, the respiration-linked, uncoupler-insensitive Na+ pump may play a role in the regulation of the intracellular salt content.

Ann Inst Pasteur Microbiol, 1986 Jan-Feb, 137A(1), 55 - 64
Growth of Azotobacter vinelandii in dialysed soil medium: studies upon the life cycle; Ballesteros F et al.; Azotobacter vinelandii ATCC 12837 cultured in dialysed soil medium with addition of 0.5% glucose showed four distinct morphological cell types: large cells, precyst forms, mature cysts and filterable corpuscles (0.3 micron in diameter) . These results indicate that Azotobacter is a bacterium with a complex life cycle under certain culture conditions . Intracellular levels of RNA and poly-beta-hydroxybutyric acid were significantly affected when cells grown in dialysed soil were compared with those obtained after growth on defined medium (N-free) . Further studies showed that the chemical composition of filterable corpuscles obtained from dialysed soil medium were different from the composition of normal Azotobacter cells produced in both culture media (dialysed soil and defined media) . We suggest that filterable corpuscles represent a stage in the life cycle of Azotobacter in their natural environment.

C R Acad Sci III, 1986, 302(17), 617 - 20
{A genetic method for exposing a given epitope at the surface of the bacterium Escherichia coli . Perspectives}; Charbit A et al.; We describe a genetic method leading to insertion of a defined epitope into certain sites of a protein . This method is applied to LamB, an outer membrane protein from Escherichia coli K12 . It allowed us to construct an "exposition vector" . The bacterial clone harboring this vector with its passenger exposes the epitope at its surface . We discuss briefly some of the perspectives which are opened by this approach concerning the study of structure and localization of proteins, the development of live vaccines and the direct cloning and exposure of unknown epitopes.

Biochemistry, 1985 Dec 17, 24(26), 7516 - 21
Picosecond kinetics of the initial photochemical electron-transfer reaction in bacterial photosynthetic reaction centers; Woodbury NW et al.; The absorption changes that occur in reaction centers of the photosynthetic bacterium Rhodopseudomonas sphaeroides during the initial photochemical electron-transfer reaction have been examined . Measurements were made between 740 and 1300 nm at 295 and 80 K by using a pulse-probe technique with 610-nm, 0.8-ps flashes . An excited singlet state of the bacteriochlorophyll dimer P* was found to give rise to stimulated emission with a spectrum similar to that determined previously for fluorescence from reaction centers . The stimulated emission was used to follow the decay of P*; its lifetime was 4.1 +/- 0.2 ps at 295 K and 2.2 +/- 0.1 ps at 80 K . Within the experimental uncertainty, the absorption changes associated with the formation of a bacteriopheophytin anion, Bph-, develop in concert with the decay of P* at both temperatures, as does the absorption increase near 1250 nm due to the formation of the cation of P, P+ . No evidence was found for the formation of a bacteriochlorophyll anion, Bchl-, prior to the formation of Bph- . This is surprising, because in the crystal structure of the Rhodopseudomonas viridis reaction center {Deisenhofer, J., Epp, O., Miki, K., Huber, R., & Michel, H . (1984) J . Mol . Biol . 180, 385-398} a Bchl is located approximately in between P and the Bph . It is possible that Bchl- (or Bchl+) is formed but, due to kinetic or thermodynamic constraints, is never present at a sufficient concentration for us to observe . Alternatively, a virtual charge-transfer state, such as P+Bchl-Bph or PBchl+Bph-, could serve to lower the energy barrier for direct electron transfer between P* and the Bph.

Eur J Biochem, 1985 Dec 16, 153(3), 477 - 84
Isolation and partial characterization of the messenger RNA encoding the B880 holochrome protein of Rhodospirillum rubrum; Belanger G et al.; The B880 holochrome messenger RNA was extracted from cultures of the photosynthetic bacterium Rhodospirillum rubrum . It was purified by chromatography on Sepharose 4B followed by sucrose density gradient centrifugation . The purified fractions were shown to program an Escherichia coli cell-free system into synthesizing both the alpha and the beta polypeptides of the holochrome . The translation products were identified by immunoprecipitation with specific antibodies raised against these polypeptides . The latter are effective competitors with the translation products for antigen-antibody complex formation . The purest mRNA preparations contained approximately 33% holochrome messenger RNA activity . Its most probable size, as determined by agarose gel electrophoresis in the presence of 6 M urea or methylmercuric hydroxide, is approximately 620 nucleotides . Since the combined sizes of the alpha and beta polypeptides add up to only 106 amino acid residues, we conclude that the holochrome mRNA is most probably polycistronic.

J Theor Biol, 1985 Dec 7, 117(3), 431 - 52
Evolution of bacterial surface exclusion against incompatible plasmids; van der Hoeven N; Many conjugative transferable plasmids exhibit surface exclusion against plasmids of the same incompatibility group . A mathematical model is developed to calculate under which conditions surface exclusion against incompatible plasmids can evolve . It appears that plasmids inducing surface exclusion can evolve and even replace non-excluding plasmids if the copy number is low and the transfer rate high provided that the cost of surface exclusion is small . They can more easily expel the non-excluding plasmids if the possession of a plasmid is not very harmful for a bacterium and if the rate at which plasmids are lost is small.

Vet Parasitol, 1985 Dec, 18(4), 367 - 73
Ticks on livestock in St . Lucia; Garris GI et al.; Cattle, sheep, goats and horses were examined for ticks . Over 95% of Holstein cross-breeds, 28% of sheep (local mixed breeds) and 18% of goats (local mixed breeds) examined from 18 August to 4 September 1983 were infested with the southern cattle tick, Boophilus microplus Canestrini . About 90 and 17% of the horses examined were infested with the tropical horse tick, Anocentor nitens Neumann, and the tropical bont tick, Amblyomma variegatum Fabricius, respectively . The tropical bont tick was found infesting 10% of cattle in the Gros Islet area of St . Lucia . The tropical bont tick was also found associated with a severe skin disease, dermatophilosis, caused by the bacterium Dermatophilus congolensis, in 54% of the cattle infested by A . variegatum in the Gros Islet and Dauphin areas of St . Lucia.

Eur J Epidemiol, 1985 Dec, 1(4), 235 - 56
Recent advances in Chlamydia trachomatis; Ladany S et al.; Chlamydia trachomatis is an obligate intracellular energy parasitic bacterium with a genome of 660 X 10(6) daltons, possessing a plasmid and unique life cycle which includes the differentiation of the infective elementary body to a replicative reticulate body . C . trachomatis is the etiological agent of trachoma, which affects approximately 500 million people in developing countries . Recently it became evident that in industrialised Western nations certain strains of C . trachomatis are the most common cause of sexually transmitted infections such as non-gonococcal urethritis, cervicitis, endometritis, salpingitis and subsequent ectopic pregnancies or infertility, perihepatitis, neonatal conjunctivitis and pneumonia, adult conjunctivitis and epididymitis . Since C . trachomatis infections are often asymptomatic, widespread screening of sexually active young people is needed in order to initiate early antibiotic treatment which may prevent serious complications such as ectopic pregnancies and infertility . Development of sensitive and simple techniques for mass screening for detection of Chlamydia in excretions as well as techniques for detection of specific markers of chronic internal infections (such as Chlamydia specific IgA antibodies) is of great importance.

Biochem J, 1985 Dec 1, 232(2), 513 - 9
Antibody-independent interaction between the first component of human complement, C1, and the outer membrane of Escherichia coli D31 m4; Aubert B et al.; The heptoseless mutant of Escherichia coli, E . coli D31 m4, binds C1q and C1 at 0 degrees C and at low ionic strength (I0.07) . Under these conditions, the maximum C1q binding averages 3.0 X 10(5) molecules per bacterium, with a Ka of 1.4 X 10(8) M-1 . Binding involves the collagen-like region of C1q, as shown by the capacity of C1q pepsin-digest fragments to bind to E . coli D31 m4, and to compete with native C1q . Proenzyme and activated forms of C1 subcomponents C1r and C1s and their Ca2+-dependent association (C1r-C1s)2 do not bind to E . coli D31 m4 . In contrast, the C1 complex binds very effectively, with an average fixation of 3.5 X 10(5) molecules per bacterium, and a Ka of 0.25 X 10(8) M-1, both comparable with the values obtained for C1q binding . C1 bound to E . coli D31 m4 undergoes rapid activation at 0 degrees C . The activation process is not affected by C1-inhibitor, and only slightly inhibited by p-nitrophenyl p'-guanidinobenzoate . No turnover of the (C1r-C1s)2 subunit is observed . Once activated, C1 is only partially dissociated by C1-inhibitor . Our observations are in favour of a strong association between C1 and the outer membrane of E . coli D31 m4, involving mainly the collagen-like moiety of C1.

J Bacteriol, 1985 Dec, 164(3), 1271 - 7
Purification and properties of the nitrogenase of Azospirillum amazonense; Song SD et al.; The nitrogenase of the free-living, microaerobic, N2-fixing bacterium Azospirillum amazonense (strain Y1) was purified by chromatography on DEAE-52 cellulose, by heat treatment, and by preparative polyacrylamide gel electrophoresis . The specific nitrogenase activities were 2,400 nmol of C2H4 formed per min per mg of protein for dinitrogenase (MoFe protein) and 1,800 nmol of C2H4 formed per min per mg of protein for dinitrogenase reductase (Fe protein) . The MoFe protein was composed of a minimum of 1,852 amino acid residues, had an isoelectric point of 5.2, and contained 2 atoms of Mo, 24 atoms of Fe, and 28 atoms of acid-labile sulfide per molecule . The Fe protein had 624 amino acid residues and an isoelectric point of 4.6 and contained four atoms of Fe and six atoms of acid-labile sulfide per molecule . The purified MoFe protein showed two subunits with molecular weights of 55,000 and 50,000 . The purified Fe protein revealed two polypeptides on sodium dodecyl sulfate-polyacrylamide gel electrophoresis with apparent molecular weights of 35,000 and 31,000 . The two Fe protein polypeptides were demonstrated with immunological techniques in the purified, highly active enzyme as well as in extracts . Also, Azotobacter vinelandii Fe protein showed two closely migrating polypeptides that migrated differently from the Fe protein polypeptides of Azospirillum brasilense or Rhodospirillum rubrum . The nitrogenase activity of Azospirillum amazonense Y1 was independent of Mn2+, and the addition of activating enzyme had no effect . No activating enzyme could be found in Azospirillum amazonense . Obviously, the nitrogenase system of Azospirillum amazonense Y1 is different from that of Azospirillum brasilense Sp7 and resembles the Azotobacter system.

Nature, 1985 Nov 21-27, 318(6043), 257 - 63
Transposition of structural genes to an expression sequence on a linear plasmid causes antigenic variation in the bacterium Borrelia hermsii; Plasterk RH et al.; In Borrelia hermsii, a spirochaete that causes relapsing fever, the switch between expression of two frequent variable major protein (VMP) types (7 and 21) is associated with a DNA rearrangement . Both cell types 7 and 21 contain untranscribed 7 and 21 VMP genes on linear plasmids . The serotype 7 cells contain an additional copy of the 7 VMP gene fused to an expression sequence on another linear plasmid . Switching to the 21 serotype involves removal of the transcribed 7 VMP gene and fusion of a copy of the 21 VMP gene to this same expression sequence . Thus recombination between linear plasmids can activate different VMP genes.

FEBS Lett, 1985 Nov 18, 192(2), 283 - 8
Expression of genes for subunits of plant-type RuBisCO from Chromatium and production of the enzymically active molecule in Escherichia coli; Viale AM et al.; A DNA fragment containing genes for both large (A) and small (B) subunits of ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO) from a photosynthetic bacterium Chromatium vinosum was ligated with vectors for expressing unfused proteins and introduced into cells of Escherichia coli . The expressers of RuBisCO were screened on agar plates using the specific antibody raised against the native enzyme from Chromatium . The production of both subunits A and B in the expressers was demonstrated by an immunoblotting experiment . The amount of RuBisCO produced in the E . coli cells was as high as 15% of the total soluble protein after induction with isopropyl-beta-D-thiogalactoside . The specific activity of enzyme molecules produced in E . coli was nearly the same as that of the original Chromatium enzyme . On gel filtration high-performance liquid chromatography the two enzymes showed identical elution behavior, strongly indicating their similar quaternary structures.

J Mol Biol, 1985 Nov 5, 186(1), 201 - 3
Characterization of bacterial photosynthetic reaction center crystals from Rhodopseudomonas sphaeroides R-26 by X-ray diffraction; Chang CH et al.; An orthorhombic crystal form (P2(1)2(1)2(1)) of the reaction center from the photosynthetic bacterium Rhodopseudomonas sphaeroides R-26 has been characterized . The crystals were grown from polyethylene glycol; the unit cell dimensions are a = 142.2 A, b = 139.6 A, and c = 78.7 A; and they contain one reaction center in each crystallographic asymmetric unit . The crystals diffract to at least 3.0 A resolution, and are suitable for detailed structural studies.

Biochemistry, 1985 Nov 5, 24(23), 6356 - 62
Purification and characterization of a calmodulin-sensitive adenylate cyclase from Bordetella pertussis; Shattuck RL et al.; Bordetella pertussis, the bacterium responsible for whooping cough, releases a soluble, calmodulin-sensitive adenylate cyclase into its culture medium . B . pertussis mutants deficient in this enzyme are avirulent, indicating that the adenylate cyclase contributes to the pathogenesis of the disease . It has been proposed that B . pertussis adenylate cyclase may enter animal cells and increase intracellular adenosine cyclic 3',5'-phosphate (cAMP) levels . We have purified the enzyme extensively from culture medium using anion-exchange chromatography in the presence and absence of calmodulin and gel filtration chromatography . The enzyme was purified 1600-fold to a specific activity of 608 mumol of cAMP min-1 mg-1 and was free of islet activating protein . The molecular weight of the enzyme was 43 400 in the absence of calmodulin and 54 200 in the presence of calmodulin . The Km of the bacterial enzyme for adenosine 5'-triphosphate was 2.0 mM, whereas the Km of the calmodulin-sensitive adenylate cyclase from bovine brain was 0.07 mM . Although the enzyme was not purified to homogeneity, its turnover number of 27 000 min-1 is the highest documented for any adenylate cyclase preparation.

J Gen Microbiol, 1985 Nov, 131 ( Pt 11), 2901 - 7
Purification and characterization of the secondary alcohol dehydrogenase from propane-utilizing Mycobacterium vaccae strain JOB-5; Coleman JP et al.; Mycobacterium vaccae strain JOB-5 cultured in the presence of propane contained an inducible secondary alcohol dehydrogenase . The enzyme was purified 198-fold using DEAE-cellulose, omega-aminopentyl agarose and NAD-agarose chromatography . The Mr of the enzyme was approximately 136000, with subunits of Mr 37000 . The pH optimum for the reaction oxidizing propan-2-ol to propanone was 10-10.5 while the optimum for the reverse reaction was 7.5-8.5 . The isoelectric point was 4.9 . NAD but not NADP could serve as electron acceptor . The apparent Km values for propan-2-ol and NAD were 4.9 X 10(-5)M and 2.8 X 10(-4)M, respectively . The enzyme was inhibited by thiol reagents and metal chelators . It appears to play an essential role in the metabolism of propane by this bacterium.

Mutat Res, 1985 Nov, 144(3), 151 - 8
Modification of survival after ultraviolet light exposure in a wild-type and a polA strain of Escherichia coli B/r by preirradiation treatment with chloramphenicol or rifampin; Doudney CO et al.; The shoulder of the UV fluence-survival curve of exponentially growing Escherichia coli B/r WP2 trpE65 was expanded by chloramphenicol pretreatment and an exponential segment with intermediate slope appeared between the shoulder and the final exponential segment . These changes were dependent on DNA replication . The transitions with UV exposure to increased slopes were ascribed to UV inactivation of qualitatively different repair systems, each dependent upon the accumulation in each bacterium of multiple DNA-containing redundant repair components, which must be inactivated before the respective transitions to decreased resistance occur . Rifampin, which blocks DNA-dependent RNA polymerase function, limited drastically expansion of the shoulder and development of the intermediate exponential slope . Bacteria defective in DNA polymerase I (polA) showed only a slight expansion of the shoulder with pretreatment with chloramphenicol . Since certain bacterial plasmids require RNA primer formation for initiation of replication and are not maintained in a polA strain, it is proposed that the chloramphenicol-promoted increase in resistance depends on the formation of multiple numbers of specific resistance episomes (called repairons in view of their role in DNA repair).

J Exp Med, 1985 Nov 1, 162(5), 1715 - 9
Fibronectin tetrapeptide is target for syphilis spirochete cytadherence; Thomas DD et al.; The syphilis bacterium, Treponema pallidum, parasitizes host cells through recognition of fibronectin (Fn) on cell surfaces . The active site of the Fn molecule has been identified as a four-amino acid sequence, arg-gly-asp-ser (RGDS), located on each monomer of the cell-binding domain . The synthetic heptapeptide gly-arg-gly-asp-ser-pro-cys (GRGDSPC), with the active site sequence RGDS, specifically competed with 125I-labeled cell-binding domain acquisition by T . pallidum . Additionally, the same heptapeptide with the RGDS sequence diminished treponemal attachment to HEp-2 and HT1080 cell monolayers . Related heptapeptides altered in one key amino acid within the RGDS sequence failed to inhibit Fn cell-binding domain acquisition or parasitism of host cells by T . pallidum . The data support the view that T . pallidum cytadherence of host cells is through recognition of the RGDS sequence also important for eukaryotic cell-Fn binding.

J Bacteriol, 1985 Nov, 164(2), 941 - 3
Regulation by carbon source of enzyme expression and slime production in bacterium W3A1; Davidson VL; Slime production by bacterium W3A1 was greatly enhanced during growth on methanol and, to a lesser extent, during growth on trimethylamine . Of the major dehydrogenases synthesized, trimethylamine and methylamine dehydrogenases were induced to different levels by certain carbon sources, while methanol dehydrogenase was expressed during growth on all carbon sources.

Mol Gen Mikrobiol Virusol, 1985 Nov, (11), 24 - 9
{Variants of the plasmid pAS8 delta with increased frequency of integration into Rhodopseudomonas sphaeroides chromosome--the result of IS8-element duplication}; Muronets EM et al.; The possible participation of IS8 and IS elements of Rhodopseudomonas sphaeroides in cointegrate formation by chromosome of the purple bacterium and plasmid pAS8-121 delta has been studied . The plasmid derivatives having deleted Tn7 have been studied . Plasmid integration into the chromosome of the purple bacterium is shown to be mediated by IS8 element of the plasmid . Plasmid derivatives having the integration potential increased for two orders were isolated by a series of intergeneric conjugational crosses during which plasmid pAS8-121 delta was transferred from Rhodopseudomonas sphaeroides (cointegrate of plasmid and chromosome) to Escherichia coli (plasmid in an autonomous state) and back to Rhodopseudomonas sphaeroides . The restriction analysis of plasmid DNA digested by Hpal and Smal restriction endonucleases has revealed the tandem duplications of IS8 in plasmids capable of integration into the chromosome of the purple bacterium with a high frequency.

Am J Surg, 1985 Nov, 150(5), 554 - 7
A cluster of true appendicitis cases; Martin DL et al.; A cluster of cases of appendicitis occurred primarily in school-age boys in a small Texas town . The expected rate of appendicitis is 1.5 cases per 1,000 persons, or about 1 case per month in that town . However, in the spring of 1984, 13 cases, 10 in school-age boys, occurred . In eight of these patients, the initial onset of abdominal pain occurred over a 15 day period . A case controlled study of school-age patients indicated that sweets in the diet and consumption of local farm eggs may have been associated with the appendicitis . We hypothesize that a group of young male patients who were susceptible to appendicitis because of the high sugar content of their diets were exposed to a bacterium or virus that precipitated this outbreak of appendicitis.

Science, 1985 Nov 1, 230(4725), 541 - 3
Transposon tagging to detect a latent virus in Myxococcus xanthus; Starich T et al.; Transposon mutagenesis of the bacterium Myxococcus xanthus with the transposon Tn5 revealed a special class of bacterial mutants that transduced the transposon through culture supernatant fluids . Virus-like particles copurified with transducing activity . Transposon tagging for detecting these virus-like particles may be generally useful in isolating endogenous viral agents capable of transferring genetic information between cells.

J Mol Biol, 1985 Oct 20, 185(4), 781 - 3
Crystallization of the activated ternary complex of ribulose-1,5-bisphosphate carboxylase-oxygenase isolated from Rhodospirillum rubrum and from an Escherichia coli clone; Choe HW et al.; Ribulose-1,5-bisphosphate carboxylase-oxygenase was purified from the photosynthetic bacterium Rhodospirillum rubrum as well as from an Escherichia coli clone overproducing the enzyme . Although the latter enzyme contains 25 additional amino acid residues at the N terminus, both preparations yielded isomorphous tetragonal, bipyramidal crystals of the ternary complex of the enzyme with CO2 and Mg2+ . Crystallization is sensitive to variation in pH and to the addition of the transition state analog, 2-carboxyarabinitol-1,5-bisphosphate . The systematic absences in the X-ray diffraction photographs suggest a tetragonal space group P4(3)2(1)2 or the enantiomorph P4(1)2(1)2 with cell dimensions a = b = 83 A, c = 290 A . There is one molecule per asymmetric unit . The resolution on still photographs is 3 A . The crystals are comparable to some of those already published but differ from others.

Biochem Biophys Res Commun, 1985 Oct 15, 132(1), 352 - 9
Suicide inhibition as a likely cause of variable specific activity in trimethylamine dehydrogenase from bacterium W3A1; Steenkamp DJ; Trimethylamine hydrogenase isolated from bacterium W3A1 grown on dimethylamine was of variable, but low specific activity and had modified spectral properties . Chemical analyses for Fe, S and P indicated that the {4Fe-4S} clusters of the modified enzyme are intact and that the covalently bound flavin is probably present, but in modified form . A peptide with absorbance maximum at 358 nm and fluorescence excitation and emission maxima in dimethylformamide at 358 nm and 495 nm, respectively, was isolated by gel chromatography and HPLC of tryptic peptides of acetamidylated, modified trimethylamine dehydrogenase . These spectral properties are similar to those of 4a- or 5a-substituted flavins and suggest that the enzyme had been modified by in vivo reaction with a suicide inhibitor . This inhibitor, or a compound giving rise to it, seems to be present in a commercial source of dimethylamine.

Nature, 1985 Oct 10-16, 317(6037), 536 - 8
GTP-binding proteins couple cardiac muscarinic receptors to a K channel; Pfaffinger PJ et al.; Binding of acetylcholine (ACh) to cardiac muscarinic ACh receptors (mAChR) activates a potassium channel that slows pacemaker activity . Although the time course of this activation suggests a multi-step process with intrinsic delays of 30-100 ms, no second-messenger system has been demonstrated to link the mAChR to the channel . Changes in cyclic nucleotide levels (cyclic AMP and cyclic GMP) do not affect this K channel or its response to muscarinic agonists . Indeed, electrophysiological experiments argue against the involvement of any second messenger that diffuses through the cytoplasm . We report here that coupling of the mAChR in embryonic chick atrial cells to this inward rectifying K channel requires intracellular GTP . Furthermore, pretreatment of cells with IAP (islet-activating protein from the bacterium Bordetella pertussis) eliminates the ACh-induced inward rectification . As IAP specifically ADP-ribosylates two GTP-binding proteins, Ni and No, that can interact with mAChRs, we conclude that a guanyl nucleotide-binding protein couples ACh binding to channel activation . This represents the first demonstration that a GTP-binding protein can regulate the function of an ionic channel without acting through cyclic nucleotide second messengers.

Immunology, 1985 Oct, 56(2), 377 - 9
Susceptibility and HLA-B27 in post-dysenteric arthropathies; van Bohemen CG et al.; A recent outbreak of bacillary dysentery in The Netherlands revealed that, despite the close association of HLA-B27 with post-dysenteric or reactive arthritis (ReA), not even in one family did all HLA-B27 positive patients infected by an arthritogenic bacterium, develop ReA . This dissociation shows that additional factors beside B27 may determine susceptibility to ReA.

J Pharmacobiodyn, 1985 Oct, 8(10), 800 - 7
Enzymatic reduction of sennidin and sennoside in Peptostreptococcus intermedius; Akao T et al.; Peptostreptococcus intermedius, one of the dominant bacteria of human intestine, reduced sennidin and sennoside to rheinanthrone and 8-glucosyl-rheinanthrone, respectively, and these reduction rates were stimulated by the addition of nicotinamide adenine dinucleotide (reduced form) (NADH), flavin adenine dinucleotide (FAD) and glucose . The reduction was accelerated by removing oxygen from the incubation tubes, which indicates the inhibition of the reduction by O2 . Thus, for the maximal activity, the reaction system required an anaerobic condition and cofactors, NADH and FAD . This bacterium also reduced methyl orange, whose mode of reduction resembled that of sennidin reduction . More than 80% of these activities were recovered in the supernatant fraction after sonication of the bacterial suspension, and these activities were purified together by means of Sephadex G-200 gel-filtration and diethylaminoethyl-cellulose column chromatography . The purified enzyme reduced FAD and benzyl viologen in the presence of NADH under an anaerobic condition.

Appl Environ Microbiol, 1985 Oct, 50(4), 1014 - 20
Glutamine synthetase activity in the ruminal bacterium Succinivibrio dextrinosolvens; Patterson JA et al.; Succinivibrio dextrinosolvens C18 was found to possess glutamine synthetase (GS), urease, glutamate dehydrogenase, and several other nitrogen assimilation enzymes . When grown in continuous culture under ammonia limitation, both GS and urease activities were high and glutamate dehydrogenase activity was low, but the opposite activity pattern was observed for growth in the presence of ample ammonia . The addition of high-level (15 mM) ammonium chloride to ammonia-limited cultures resulted in a rapid loss of GS activity as measured by either the gamma-glutamyl transferase or forward assay method with cells or extracts . No similar activity losses occurred for urease, glutamate dehydrogenase, or pyruvate kinase . The GS activity loss was not prevented by the addition of chloramphenicol and rifampin . The GS activity could be recovered by washing or incubating cells in buffer or by the addition of snake venom phosphodiesterase to cell extracts . Manganese inhibited the GS activity (forward assay) of untreated cells but stimulated the GS activity in ammonia-treated cells . Alanine, glycine, and possibly serine were inhibitory to GS activity . Optimal pH values for GS activity were 7.3 and 7.4 for the forward and gamma-glutamyl transferase assays, respectively . The glutamate dehydrogenase activity was NADPH linked and optimal in the presence of KCl . The data are consistent with an adenylylation-deadenylylation control mechanism for GS activity in S . dextrinosolvens, and the GS pathway is a major route for ammonia assimilation under low environmental ammonia levels . The rapid regulation of the ATP-requiring GS activity may be of ecological importance to this strictly anaerobic ruminal bacterium.

Biochemistry, 1985 Sep 10, 24(19), 5247 - 53
Characterization of membrane lipids of a general fatty acid auxotrophic bacterium by electron spin resonance spectroscopy and differential scanning calorimetry; Hauser H et al.; Lipids in the plasma membrane of the general fatty acid auxotroph Butyrivibrio S2 pack as a bilayer that is characterized by a high order and high motional anisotropy and a low membrane fluidity compared to mammalian plasma membranes . Lipid packing as determined by the electron spin resonance (ESR) order parameter and membrane fluidity as measured by ESR correlation times are, however, comparable to those of other bacterial membranes . Membranes of the organism grown with saturated fatty acids of well-defined hydrocarbon chain length undergo a broad reversible endothermic phase transition, the peak temperature of which is well below the growth temperature; the end-point temperature of this thermal transition approximately coincides with the minimum temperature supporting significant growth of the organism . The lipid phase transition is also reflected in the temperature dependence of various ESR parameters, whereby the transition temperature thus derived is higher than the peak temperature of the endothermic transition but still lower than the growth temperature . ESR and calorimetry evidence taken together suggest that the endothermic transition is a gel to liquid-crystal transition and that, at the growth temperature, the plasma membrane of Butyrivibrio S2 is in the liquid-crystalline state . Similar values were measured for the order parameter of cell membranes of Butyrivibrio S2 regardless of whether the organism was grown on myristic, palmitic, or stearic acid . Butyrivibrio S2 has a mechanism enabling it to maintain membrane packing and fluidity at a fairly constant level.(ABSTRACT TRUNCATED AT 250 WORDS)

Eur J Biochem, 1985 Sep 2, 151(2), 333 - 5
The amino acid sequences of the copper/zinc superoxide dismutases from swordfish and Photobacter leiognathi confirm the predictions made from the compositions; Cornish-Bowden A; Recent suggestions that the amino acid sequence of the copper/zinc superoxide dismutases of swordfish and Photobacter leiognathi do not support the theory that the bacterium obtained the gene for the enzyme by transfer from its eucaryotic symbiont {Rocha, H . A., Bannister, W . H . and Bannister, J . V . (1984) Eur . J . Biochem . 145, 477-484} are examined . The amount of difference between the sequence is in good agreement with expectation from the amino acid compositions . Moreover, the gene-transfer hypothesis cannot be discarded without postulating an enormous increase in the rate at which the superoxide dismutase gene has accumulated amino acid substitutions since the divergence of the swordfish and cattle lineages.

Arch Microbiol, 1985 Sep, 142(4), 333 - 9
The Rhodopseudomonas viridis photosynthetic membrane: arrangement in situ; Miller KR et al.; The organization of photosynthetic membranes in the cytoplasm of the photosynthetic bacterium Rh . viridis has been examined by several techniques for electron microscopy . Thin sections of membrane stacks show that the regular lattice of membrane subunits reported in other studies can be observed in thin section . Tilting of sections in the electron microscope shows that the regular lattices of several membranes overlap in a way that suggests they are in register with each other . This observation can be confirmed by freeze-fracture images in which a regular arrangement of membrane lattices can be observed, each perfectly aligned . Analysis of the spacings of membrane pairs shows that the photosynthetic membranes of Rh . viridis are very closely apposed . The mean diameter of two membranes is 160A, and the average space between two such membranes is only 42A . When a recently developed atomic level model of Rh . viridis reaction center is superimposed against these spacings, each reaction center extends from the surface of its respective membrane far enough to make contact with an apposing membrane . The limited free space between membranes and regular alignment of lattices has a number of implications for how this membrane is organized to carry out the process of energy transfer.

Infect Immun, 1985 Sep, 49(3), 775 - 9
Correlation of plasmid type and disease caused by Coxiella burnetii; Samuel JE et al.; The obligate intracellular bacterium Coxiella burnetii is the etiological agent of acute Q-fever and chronic endocarditis in humans and of several zoonotic infections . The DNA from a variety of these disease isolates was compared for homology to the plasmid QpH1, found in the Nine Mile strain . Three patterns of homology were found in these isolates, i.e., one pattern identical to that of QpH1, one common to several endocarditis isolates and goat abortion isolates, and one common to the remaining group of endocarditis isolates . Plasmid DNA from the endocarditis-abortion isolate group, designated QpRS, was mapped by restriction enzyme analysis and compared with QpH1 . These data show that QpRS was 2 to 3 kilobase pairs larger, contained DNA not found in QpH1, but was not generated from QpH1 by a single insertional event . Isolation of plasmid DNA from the second endocarditis group of isolates was not successful and may indicate that the plasmid has integrated into the chromosome . This analysis provides the first clear evidence that differences exist between C . burnetii isolates which cause various diseases, indicating that different C . burnetii strains may have unique virulence characteristics.

J Gen Microbiol, 1985 Sep, 131 ( Pt 9), 2377 - 85
Growth inhibition of Escherichia coli by E colicin plasmids; Brunner DP et al.; Plasmids were isolated from E colicinogenic strains and transformed into prototrophic Escherichia coli K 12 strain DB364 . Screening of E colicinogenic transformants for growth on defined medium revealed an apparent amino acid auxotrophy mediated by E4 and, to a lesser extent, E7 colicin plasmids . The auxotrophy was further investigated in E4 colicinogenic strains . From such auxotrophic transformants, denoted Pmi+ (plasmid-mediated inhibition of growth), Pmi- variants were obtained at a frequency of 3 X 10(-4) per bacterium . Plasmid loss was not detected among Pmi- clones . Isolation of E4 colicin plasmids from Pmi- clones and retransformation of strain DB364 with these plasmids showed that 40% of the plasmids were unable to inhibit growth of DB364 and were inferred to have alterations in an E4 colicin plasmid gene termed pmi . All such plasmids were indistinguishable from native E4 colicin plasmids, with respect to colicin immunity, colicin production and excretion, and sensitivity to lysis by mitomycin C . Experiments examining the nutritional basis of the plasmid-mediated auxotrophy indicated that at least seven amino acids, isoleucine, leucine, valine, arginine, methionine, serine and glycine, were involved in the auxotrophy . However, supplementation with only these seven amino acids did not completely restore growth . Assays of the activities of enzymes involved in amino acid biosynthesis in colicinogenic and non-colicinogenic strains under repressing and derepressing growth conditions suggested that E4 colicin plasmids did not repress synthesis of the implicated amino acids.

Proc Natl Acad Sci U S A, 1985 Sep, 82(17), 5973 - 7
Mini-F plasmid-induced SOS signal in Escherichia coli is RecBC dependent; Bailone A et al.; Dispensable replicons such as F plasmid {95 kilobases (kb)} or its mini-derivatives such as mini-F (9.3 kb) or lambda mini-F efficiently induced cellular SOS genes such as sfiA (sulA) when they were damaged by UV irradiation and then introduced into a recipient bacterium . To generate an SOS signal, UV light-damaged mini-F or mini-F conditional mutants deficient in replication required that the bacterial RecBC enzyme retained some activity different from the nuclease activity that was dispensable . In contrast, UV light-damaged F plasmid produced an SOS signal independently of the activity of the RecBC enzyme and of the expression of the mini-F, -H, and -G proteins . Our findings are consistent with a picture in which the SOS signal is constituted by stretches of single-stranded DNA on a replicon . Moreover, our present data combined with other data previously published lead to the hypothesis that the SOS signal induced by mini-F plasmid is located in trans on the host chromosome, whereas the one generated by UV light-damaged F plasmid is in cis on the transferred DNA.

J Biochem (Tokyo), 1985 Sep, 98(3), 819 - 24
Mechanisms of growth inhibition by propionate and restoration of the growth by sodium bicarbonate or acetate in Rhodopseudomonas sphaeroides S; Maruyama K et al.; Mechanisms of growth inhibition by propionate on the growth of Rhodopseudomonas sphaeroides were studied . Partially purified pyruvate dehydrogenase complex (PDC) from R . sphaeroides was inhibited by propionyl-CoA, one of the metabolic intermediates of propionate, while propionate itself did not inhibit the enzyme . This suggests that the inhibitor of the growth in vivo is not propionate but propionyl-CoA . The inhibition by propionyl-CoA was competitive with respect to coenzyme A concentration . The K1 value for propionyl-CoA was 0.84 mM . Addition of NaHCO3, which restored the growth of this bacterium in the presence of propionate, increased the rate of propionate incorporation by 1.7-fold and decreased the intracellular level of propionyl-CoA by half . These findings suggest that HCO3-ion lowers the level of propionyl-CoA by accelerating its carboxylation reaction, which is catalyzed by propionyl-CoA carboxylase . Effects of NaHCO3 and acetate on the growth restoration were also studied by the use of propionyl-CoA carboxylase-deficient mutants . NaHCO3 did not restore the growth of the mutants, indicating an essential role of propionyl-CoA carboxylase on the restoration of growth by NaHCO3 as suggested above . Addition of acetate restores the growth of the mutants in the presence of propionate . Acetate probably restores the growth by supplying acetyl-CoA.

J Hosp Infect, 1985 Sep, 6(3), 323 - 5
Branhamella catarrhalis cellulitis around a cerebrospinal fluid shunt: case report; Kaufman BA et al.; A cellulitis surrounding a cerebrospinal fluid shunt caused by Branhamella catarrhalis is described . This is the first reported case of a cellulitis caused by this bacterium.

J Biol Chem, 1985 Aug 25, 260(18), 10288 - 92
Photoaffinity labeling of an antimycin-binding site in Rhodopseudomonas sphaeroides; Wilson E et al.; Tritium-labeled 3-azidosalicyl-N-(n-octadecyl)amide was synthesized and used as a photoaffinity probe for the antimycin-binding site in both purified ubiquinone-cytochrome b-c1 oxidoreductase and chromatophore vesicles from the photosynthetic bacterium Rhodopseudomonas sphaeroides . In both systems, a prominently labeled protein had a molecular weight of 11,000 . Binding to this protein was inhibited by preincubation of the reaction mixture with antimycin prior to addition of the radioactive analog and subsequent irradiation . The antimycin analog, 3-azidosalicyl-N-(n-octadecyl)amide, inhibited succinate-cytochrome c reductase activity in chromatophore vesicles by 50% at a concentration of 150 nmols/mg of protein.

J Biol Chem, 1985 Aug 15, 260(17), 9642 - 7
The biosynthesis and assembly of methanol dehydrogenase in bacterium W3A1; Davidson VL et al.; Bacterium W3A1, a restricted facultative methylotroph, produces a periplasmic methanol dehydrogenase composed of two identical subunits of Mr = 57,300, and two noncovalently bound methoxatin prosthetic groups . A precursor form of Mr = 1,500 larger than the mature subunit was identified among the products of an in vitro translation of total RNA isolated from bacterium W3A1 . The precursor form of the protein could not be detected in cells during in vivo pulse-labeling studies, suggesting that the processing of this precursor occurs entirely co-translationally . Whereas the holoenzyme was detectable only as a dimer, removal of the prosthetic group yielded an apoenzyme that could be detected as either a dimeric or monomeric species . After readdition of the purified prosthetic group to the apoenzyme, only the dimeric form of the protein, bearing the cofactor and exhibiting an absorption spectrum similar to that of the holoenzyme, was detected . Neither the mature apoprotein nor the holoenzyme demonstrated any affinity for phospholipid membranes, as assayed by their inability to bind to liposomes . Taken together, these data suggest a scheme of co-translational processing and export of the apoprotein subunits, followed by assembly of the subunits and prosthetic groups in the periplasmic space to form the mature holoenzyme . The suitability of bacterium W3A1, and other methylotrophic bacteria, for use in studies of protein biosynthesis and export, is also discussed.

J Mol Biol, 1985 Aug 5, 184(3), 479 - 502
Refined structure of alpha-lytic protease at 1.7 A resolution . Analysis of hydrogen bonding and solvent structure; Fujinaga M et al.; The structure of alpha-lytic protease, a serine protease produced by the bacterium Lysobacter enzymogenes, has been refined at 1.7 A resolution . The conventional R-factor is 0.131 for the 14,996 reflections between 8 and 1.7 A resolution with I greater than or equal to 2 sigma (I) . The model consists of 1391 protein atoms, two sulfate ions and 156 water molecules . The overall root-meansquare error is estimated to be about 0.14 A . The refined structure was compared with homologous enzymes alpha-chymotrypsin and Streptomyces griseus protease A and B . A new sequence numbering was derived based on the alignment of these structures . The comparison showed that the greatest structural homology is around the active site residues Asp102, His57 and Ser195, and that basic folding pathways are maintained despite chemical changes in the hydrophobic cores . The hydrogen bonds in the structure were tabulated and the distances and angles of interaction are similar to those found in small molecules . The analysis also revealed the presence of close intraresidue interactions . There are only a few direct intermolecular hydrogen bonds . Most intermolecular interactions involve bridging solvent molecules . The structural importance of hydrogen bonds involving the side-chain of Asx residues is discussed . All the negatively charged groups have a counterion nearby, while the excess positively charged groups are exposed to the solvent . One of the sulfate ions is located near the active site, whereas the other is close to the N terminus . Of the 156 water molecules, only seven are not involved in a hydrogen bond . Six of these have polar groups nearby, while the remaining one is in very weak density . There are nine internal water molecules, consisting of two monomers, two dimers and one trimer . No significant second shell of solvent is observed.

J Biochem Biophys Methods, 1985 Aug, 11(2-3), 83 - 93
A polyvinylchloride-membrane based anion selective electrode for continuous registration of delta pH (interior alkaline) with salicylate as the indicator probe; Hellingwerf KJ et al.; An anion sensitive electrode has been constructed with the use of the lipid soluble cation benzyl-dimethyl-hexadecylammonium analogous to the procedure described for tetraphenylphosphonium-sensitive electrodes {Shinbo, T., Kamo, N., Kurihara, K . and Kobatake, Y . (1978) Arch . Biochem . Biophys . 187, 414-422} . The anion electrode responds to salicylate concentrations above 400 microM with a Nernstian sensitivity . Less lipid soluble anions like chloride and phosphate do not interfere . Below 400 microM salicylate the response of the electrode decreases gradually so that the sensitivity of the electrode is less than 10 mV per decade change at concentrations of the anion of 50 microM . A computer program has been developed to fit the electrode response curve with a polynomal function of the fourth power . Additional software-allows calculation of changes in the concentration of the salicylate anion, also under conditions where the sensitivity of the electrode for the anion is not constant . In this way the electrode can be used to measure changes in salicylate concentration that occur in a suspension of bacteria when, upon energization, a pH gradient is generated . 31P nuclear magnetic resonance measurements demonstrated that the pH gradient measured with the salicylate-sensitive electrode in the phototrophic bacterium Rhodopseudomonas sphaeroides is quantitatively correct . The response time of the electrode decreases from 1 min at 20 microM salicylate to 10 s at concentrations greater than or equal to 200 microM.

J Bacteriol, 1985 Aug, 163(2), 635 - 9
Purification and characterization of hydrolytic haloalkane dehalogenase from Xanthobacter autotrophicus GJ10; Keuning S et al.; A new enzyme, haloalkane dehalogenase, was isolated from the 1,2-dichloroethane-utilizing bacterium Xanthobacter autotrophicus GJ10 . The purified enzyme catalyzed the hydrolytic dehalogenation of n-halogenated C1 to C4 alkanes, including chlorinated, brominated, and iodinated compounds . The highest activity was found with 1,2-dichloroethane, 1,3-dichloropropane, and 1,2-dibromoethane . The enzyme followed Michaelis-Menten kinetics, and the Km for 1,2-dichloroethane was 1.1 mM . Maximum activity was found at pH 8.2 and 37 degrees C . Thiol reagents such as p-chloromercuribenzoate and iodoacetamide rapidly inhibited the enzyme . The protein consists of a single polypeptide chain of a molecular weight of 36,000, and its amino acid composition and N-terminal sequence are given.

Zentralbl Bakteriol Mikrobiol Hyg {A}, 1985 Aug, 260(1), 100 - 7
Adherence of Fusobacterium necrophorum to Vero cells; Kanoe M et al.; The adherence of the anaerobic species Fusobacterium necrophorum to the surface of Vero cells was studied . Adherence between the bacterium and the tissue culture cells was paralleled by the hemagglutinability of F . necrophorum . Treatment of the bacterial cells with lactoalbumin hydrolysate or anti-F . necrophorum-hemagglutinin serum reduced the intensity of the attachment . The purified hemagglutinin bound to the membranes of Vero cells . It lost its adherent property when mixed with the homologous anti-hemagglutinin serum . These observations suggest that the adherence of F . necrophorum to the surface of Vero cells is mediated by the bacterial hemagglutinin.

Biophys J, 1985 Aug, 48(2), 311 - 20
The effect of an applied electric field on the charge recombination kinetics in reaction centers reconstituted in planar lipid bilayers; Gopher A et al.; Reaction Centers (RCs) from the photosynthetic bacterium Rhodopseudomonas sphaeroides were incorporated in planar bilayers made from monolayers derived from liposomes reconstituted with purified RCs . The photocurrents associated with the charge recombination process between the reduced primary quinone (QA-) and the oxidized bacteriochlorophyll donor (D+) were measured as a function of voltage (-150 mV less than V less than 150 mV) applied across the bilayer . When QA was the native ubiquinone (UQ) the charge recombination was voltage independent . However, when UQ was replaced by anthraquinone (AQ), the recombination time depended on the applied voltage V according to the relation tau = 8.5 X 10(-3) eV/0.175S . These results were explained by a simple model in which the charge recombination from UQ- proceeds directly to D+ while that from AQ occurs via a thermally activated intermediate state, D+I-QA, where I is the intermediate acceptor . The voltage dependence arises from an electric field induced change in the energy gap, delta G0, between the states D+I-QA and D+IQA- . This model is supported by the measured temperature dependence of the charge recombination time, which for RCs with AQ gave a value of delta G0 = 340 +/- 20 meV . In contrast, delta G0 for RCs with UQ as the primary acceptor, is sufficiently large (approximately 550 meV) so that even in the presence of the field, the direct pathway dominates . The voltage dependence shows that the electron transfer from I- to QA is electrogenic . From a quantitative analysis of the voltage dependence on the recombination rate it was concluded that the component of the distance between I and QA along the normal to the membrane is about one-seventh of the thickness of the membrane . This implies that the electron transfer from I to Q contributes at least one-seventh to the potential generated by the charge separation between D+ and QA-.

Biochem J, 1985 Aug 1, 229(3), 701 - 10
Lipid biosynthesis in synchronized cultures of the photosynthetic bacterium Rhodopseudomonas sphaeroides; Knacker T et al.; Lipid biosynthesis has been studied in photosynthetic cultures of Rhodopseudomonas sphaeroides that had been synchronized by stationary-phase cycling or by a centrifugation selection procedure . Synchrony index values in the range 0.70-0.80 were obtained for the first cell cycle with both synchronization methods . The major membrane lipids phosphatidylethanolamine and phosphatidylglycerol were accumulated discontinuously during the cell cycle, their mass doubling immediately before cell division . This accumulation of lipid corresponded to peaks in incorporation of radioactivity from either {1-14C}acetate or {2-3H}glycerol into individual acyl lipids as measured in individual portions of bacteria . For phosphatidylglycerol an additional peak of incorporation of radioactivity from {2-3H}glycerol was found midway through the cell cycle . In spite of their rather similar endogenous fatty acid compositions, the individual phosphoacylglycerols showed distinctive patterns of incorporation of radioactivity from {1-14C}acetate into their acyl moieties . The discontinuous synthesis of acyl lipids observed in cultures of Rhodopseudomonas sphaeroides synchronized by either stationary-phase cycling or centrifugation selection procedures contrasted with the accumulation of chlorophyll-protein complexes whose amounts were found to increase throughout the cell cycle . The implications of these findings for the control of lipid synthesis in bacterial photosynthetic membranes are discussed.

Arch Microbiol, 1985 Aug, 142(3), 248 - 52
Expression of genes from the marine bacterium Alteromonas haloplanktis 214 in Escherichia coli K-12; MacLeod RA et al.; DNA from the marine bacterium Alteromonas haloplanktis 214 was partially digested with Sau 3A and inserted into the Bam HI site of the cloning vector pBR322 . The ligation mixture was used to transform Escherichia coli HB101 . The gene bank plasmid preparation obtained was used to transform Escherichia coli K-12 strain EO2717, an organism auxotrophic for histidine, arginine, adenine, uracil and thiamin . Prototrophic transformants for each of the five metabolites were isolated using appropriate minimal media for selection . Plasmids isolated from each of the transformants were shown by hybridization to contain A . haloplanktis DNA and to be capable of complementing the appropriate mutation in E . coli EO2717 . Restriction maps showed that each of the plasmids was different.

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