Bacteria

Biochem J, 1985 Aug 1, 229(3), 663 - 8
Transcription of Rhodospirillum rubrum atp operon; Falk G et al.; The photosynthetic non-sulphur bacterium Rhodospirillum rubrum contains a cluster of five genes encoding the subunits of F1-ATPase {Falk, Hampe & Walker (1985) Biochem . J . 228, 391-407} . Transcription of these genes has been studied by two methods, transcriptional mapping with S1 nuclease and primer extension analysis . Thereby a 5'-end in RNA derived from this region has been demonstrated at a guanine residue 236 bases before the initiation codon of the gene for the delta-subunit, the first in this cluster . DNA sequences on the 5' side of this nucleotide show some similarity to promoters in Escherichia coli, but are not apparently related to sequences upstream of the Rhodopseudomonas blastica atp operon . A 3'-end in RNA derived from this gene cluster has been demonstrated by S1-nuclease mapping . This is found before a run of thymidylate residues in the DNA, on the 3' side of a region of dyad symmetry . In E . coli these features are characteristic of rho-independent transcriptional termination signals . It appears from these studies and from the organization of the genes that the five genes in the atp cluster may be co-transcribed from this promoter and that transcripts terminate at the region of dyad symmetry.

J Biol Chem, 1985 Jul 15, 260(14), 8430 - 7
Branch point control by the phosphorylation state of isocitrate dehydrogenase . A quantitative examination of fluxes during a regulatory transition; Walsh K et al.; To understand how enzymatic pathways respond to changing external conditions, the fluxes through the tricarboxylic acid cycle and ancillary reactions were determined under three different growth conditions in Escherichia coli . The velocities through the major steps in each pathway were measured (a) for growth on acetate alone, (b) for growth on acetate plus glucose, and (c) during the transition caused by addition of glucose to cells growing on acetate . During the transition, the carbon flow through the Krebs cycle decreased by a factor of 5 despite an increase in the growth rate of the culture . Under these conditions, the dephosphorylation of isocitrate dehydrogenase caused a 4-fold increase in its activity . This, together with the decreased rate of substrate production and the kinetic parameters of the branch point enzymes, led to a cessation of the flux through the glyoxylate shunt . The decreased rate of acetyl-CoA turnover, not an inhibition of acetate transport, caused a slower rate of acetate uptake in the presence of glucose . The modulation of protein phosphorylation and metabolite levels is one of the regulatory mechanisms which enables the bacterium to make dramatic shifts between metabolic pathways within a fraction of a doubling time.

Jpn J Cancer Res, 1985 Jul, 76(7), 657 - 62
Antitumor activity of Sphaerotilus natans and its slime fraction in mice; Mifuchi I et al.; Antitumor activity of the whole cell and slime of an aquatic sheathed bacterium, Sphaerotilus natans IAM 12068, against ascites form of Ehrlich carcinoma in ddY mice was investigated . Intraperitoneal injection of whole cells and the slime fraction showed remarkable antitumor activity against mice inoculated with 10(4) to 10(5) tumor cells, the slime fraction being more effective . To examine the chemical nature of the active principle in the slime fraction, separation by Sepharose 4B gel filtration was carried out and two fractions designated as GF-P-1 and GF-P-2, which are mainly composed of protein, carbohydrate, and lipid, were obtained . GF-P-1 fraction, which contains large amounts of fucose and unidentified sugar as neutral sugar, showed marked antitumor activity at half the dose of the slime fraction, whereas the antitumor activity of GF-P-2, which is composed mainly of protein, was weak . This finding indicates that GF-P-1 fraction of S . natans slime may be a main active principle . The consistently demonstrable antitumor activity of GF-P-1 was abrogated by treatment of mice with silica, an anti-macrophage agent, suggesting that the antitumor activity of GF-P-1 depends on the activation of macrophages.

Nature, 1985 Jun 20-26, 315(6021), 686 - 8
Lattice mobility and anomalous temperature factor behaviour in cytochrome c'; Finzel BC et al.; Atomic temperature factors (B-values) obtained from X-ray refinement experiments provide empirical estimates of protein mobility that have been correlated with both theoretical simulations of protein dynamics and experimental studies of antibody reactivity . The comparison of B-values with protein solution properties requires adjustment of the apparent atomic mobilities to compensate for the effects of the crystal environment . Here we compare crystallographically independent subunits of the dimeric cytochrome c' from the bacterium Rhodospirillum molischianum to examine how lattice effects influence refined B-values . In addition to local effects on protein mobility at crystal contacts, we show that B-value differences up to 12 A between subunits result from lattice disordering effects that approximate to concerted rotations of the molecules about a crystal symmetry axis.

Biochem J, 1985 Jun 15, 228(3), 769 - 71
A novel hopanoid, 30-(5'-adenosyl)hopane, from the purple non-sulphur bacterium Rhodopseudomonas acidophila, with possible DNA interactions; Neunlist S et al.; A novel hopanoid, 30-(5'-adenosyl)hopane, was isolated from the purple non-sulphur bacterium Rhodopseudomonas acidophila and identified . The significance of this triterpenoid in terms of bacteriohopanepolyol biosynthesis, membrane reinforcement and possible interactions with nucleic acids is discussed.

J Biochem (Tokyo), 1985 Jun, 97(6), 1679 - 88
Intermolecular fructosyl and levanbiosyl transfers by levan fructotransferase of Arthrobacter ureafaciens; Tanaka K et al.; A purified levan fructotransferase preparation from the culture of the bacterium Arthrobacter ureafaciens, which produces di-D-fructose 2,6':6,2' dianhydride (difructose anhydride IV) from levan by an intramolecular levan fructosyl transfer (ILFT) reaction, was found to produce a trioligofructan and a tetraoligofructan from levan in the presence of levanbiose, indicating the intermolecular fructosyl and levanbiosyl transfer (LFT and LBT) reactions . The tri- and tetraoligofructans were identified to be levantriose and -tetraose respectively . Increase in the levanbiose concentration brought about increased production of both oligofructans with decreased formation of difructose anhydride IV, supporting the previous theory proposed by Tanaka et al . (1983) that the ILFT, LFT, and LBT reactions are catalyzed by the same enzyme . In addition, there existed a roughly stoichiometric relationship between the increase and decrease in the productions of these oligofructans, and the LBT reaction was found to occur more intensively than the LFT reaction . Acceptor specificity of the LFT and LBT reactions was studied using fifteen sugars including mono-, di-, and trisaccharides . The enzyme showed both of the reactions only with levanbiose, -triose, and kestose, indicating that the exposed non-reducing levanbiosyl residue was essential for the acceptor and suggesting the existence of a levanbiosyl acceptor site on the enzyme molecule.

Proc Natl Acad Sci U S A, 1985 Jun, 82(11), 3616 - 20
Bacterial peptide chain release factors: conserved primary structure and possible frameshift regulation of release factor 2; Craigen WJ et al.; Escherichia coli peptide chain release factors are proteins that direct the termination of translation in response to specific peptide chain termination codons . The mechanisms of codon recognition and peptidyl-tRNA hydrolysis are unknown . We have characterized the genes encoding release factor 1 (RF-1) and release factor 2 (RF-2) to study the structure-function relationships of the proteins and their regulation in the bacterium . In this report, we present the gene structure of RF-1 and RF-2, and a partial peptide sequence of RF-2 . RF-1 and RF-2 are highly homologous in their primary structure . In addition, an in-frame premature opal (UGA) termination codon is located within the RF-2 coding region at amino acid position 26 . This region of the protein was sequenced by automated Edman degradation to confirm the predicted reading frame, and a second independent isolate of the RF-2 gene was identified and sequenced to confirm the DNA sequence . These results imply that a frameshift occurs prior to the premature termination codon, thus allowing for translation of RF-2 to be completed . This may represent a mechanism of translational control of RF-2 expression . An alternative possible means of translational regulation is discussed.

Biochem J, 1985 Jun 1, 228(2), 391 - 407
Nucleotide sequence of the Rhodospirillum rubrum atp operon; Falk G et al.; The nucleotide sequence was determined of a 8775-base-pair region of DNA cloned from the photosynthetic non-sulphur bacterium Rhodospirillum rubrum . It contains a cluster of five genes encoding F1-ATPase subunits . The genes are arranged in the same order as F1 genes in the Escherichia coli unc operon . However, as in the related organism Rhodopseudomonas blastica, neither genes for components of F0, the membrane sector of ATP synthase, nor a homologue of the E . coli uncI gene are associated with this locus, as they are in E . coli.

Science, 1985 May 31, 228(4703), 1101 - 3
Adaptation of the membrane lipids of a deep-sea bacterium to changes in hydrostatic pressure; DeLong EF et al.; The fatty acid composition of the cell membrane of the barophilic marine bacterium CNPT3 was found to vary as a function of pressure . Greater amounts of unsaturated fatty acids were present in bacteria growing at higher pressures . The results suggest adaptations in the membrane lipids to environmentally relevant pressures . This response to pressure appears to be analogous to temperature-induced membrane adaptations observed in other organisms.

Biochim Biophys Acta, 1985 May 31, 807(3), 308 - 19
Soluble cytochrome composition of the purple phototrophic bacterium, Rhodopseudomonas sphaeroides ATCC 17023; Meyer TE et al.; A detailed study of the soluble cytochrome composition of Rhodopseudomonas sphaeroides (ATCC 17023) indicates that there are five c-type cytochromes and one b-type cytochrome present . The molecular weights, heme contents, amino acid compositions, isoelectric points, and oxidation-reduction potentials were determined and the proteins were compared with those from other bacterial sources . Cytochromes c2 and c' have previously been well characterized . Cytochrome c-551.5 is a diheme protein which has a very low redox potential, similar to certain purple bacterial and algal cytochromes . Cytochrome c-554 is an oligomer, which is spectrally similar to the low-spin isozyme of cytochrome c' found in other purple bacteria (e.g., Rhodopseudomonas palustris cytochrome c-556) . An unusual high-spin c-type heme protein has also been isolated . It is spectrally distinguishable from cytochrome c' and binds a variety of heme ligands including oxygen . A large molecular-weight cytochrome b-558 is also present which appears related to a similar protein from Rhodospirillum rubrum, and the bacterioferritin from Escherichia coli . None of the soluble proteins appear to be related to the abundant membrane-bound c-type cytochrome in Rps . sphaeroides which has a larger subunit molecular weight similar to mitochondrial cytochrome c1 and chloroplast cytochrome f.

Science, 1985 May 24, 228(4702), 958 - 62
Expression of Plasmodium falciparum circumsporozoite proteins in Escherichia coli for potential use in a human malaria vaccine; Young JF et al.; The circumsporozoite (CS) protein of the human malaria parasite Plasmodium falciparum may be the most promising target for the development of a malaria vaccine . In this study, proteins composed of 16, 32, or 48 tandem copies of a tetrapeptide repeating sequence found in the CS protein were efficiently expressed in the bacterium Escherichia coli . When injected into mice, these recombinant products resulted in the production of high titers of antibodies that reacted with the authentic CS protein on live sporozoites and blocked sporozoite invasion of human hepatoma cells in vitro . These CS protein derivatives are therefore candidates for a human malaria vaccine.

J Biol Chem, 1985 May 10, 260(9), 5526 - 32
Bordetella pertussis invasive adenylate cyclase . Partial resolution and properties of its cellular penetration; Hanski E et al.; The existence of an invasive adenylate cyclase in dialyzed urea extracts of the bacterium Bordetella pertussis has been suggested recently . Gel filtration of B . pertussis dialyzed urea extract shows that the invasive enzyme constitutes only a small portion of the total adenylate cyclase activity found in the extract . Its size is different than the size of the two peaks of adenylate cyclase activity identified in the extract . Ca2+ is absolutely required for the penetration of the invasive enzyme, it also controls the rate of intracellular cAMP accumulation in human lymphocytes exposed to dialyzed extract . These characteristics may be attributed to the increase in the size of the invasive enzyme as found by gel filtration chromatography of the extract in the absence of Ca2+ . Removal of nonpenetrating adenylate cyclase that adheres to lymphocytes permits a direct assay of the intracellular enzyme . The time course of intracellular accumulation of adenylate cyclase activity is similar to the time course of intracellular accumulation of cAMP, suggesting that the invasive enzyme is rapidly deactivated, but not degraded, since it can be detected upon cell disruption . No appreciable amount of the enzyme is introduced when cells are incubated with extract at 4 degrees C for 120 min, then washed and incubated further at 37 degrees C . Concanavalin A inhibits cAMP accumulation irrespective of the time of its addition, and EGTA prevents penetration of the invasive enzyme even if added 20 min after addition of extract . These findings are different from those observed in other bacterial toxins thought to be internalized by receptor-mediated endocytosis . However, the cellular penetration of B . pertussis adenylate cyclase is cell-selective . It does not occur in human erythrocytes . In addition to human lymphocytes, S49 cyc- murine lymphoma, turkey erythrocytes, and rat oocytes accumulate cAMP in response to B . pertussis extract.

Prikl Biokhim Mikrobiol, 1985 May-Jun, 21(3), 422 - 7
{Gas chromatographic determination of amino acid configuration in the optically active stationary phase}; Muratov VB et al.; The synthesis and physico-chemical properties of a novel optically active stationary phase--N-stearoyl-L-valyl-t-butylamide (I) applied for GLC separation of enantiomeric alpha-amino acids are described . The optical purity of the compound (I) is not less than 85% . The efficiency of the phase is shown on analyses of the configuration of amino acids in peptidolipids and glycopeptidolipids produced by the paraffin-oxidizing bacterium Mycobacterium paraffinicum.

Infect Immun, 1985 May, 48(2), 417 - 21
Nonimmune binding of equine immunoglobulin by the causative organism of contagious equine metritis, Taylorella equigenitalis; Widders PR et al.; This study identifies nonimmune binding of equine immunoglobulin by the causative organism of contagious equine metritis . Immunoglobulin binding to the bacterium was strongest for immunoglobulin G (IgG) and less for IgM; IgA was not bound . Binding of equine IgG was inhibited by human IgG, but not by IgG of domestic animals . Immunoglobulin binding by the bacterium appeared to be directed towards an epitope in the hinge region of the immunoglobulin molecule.

J Immunol, 1985 May, 134(5), 2900 - 7
Site-selective homing of antigen-primed lymphocyte populations can play a crucial role in the efferent limb of cell-mediated immune responses in vivo; Spangrude GJ et al.; Lymphoid cells of the mammalian immune system exhibit special migratory properties within their in vivo environment . This fundamental characteristic is important to the protection of the organism from infection and neoplastic transformation by a process termed immunologic surveillance . The importance of lymphocyte recirculation was addressed by investigating the role of site-selective homing of lymphocytes during the efferent phase of an in vivo adoptively transferred immune response . We approached this problem by using pertussis toxin (PT), a known inhibitor of lymphoid cell migration in vivo . PT is a protein secreted by the bacterium Bordetella pertussis, which induces a selective and long-lasting inhibition of the emigration of lymphocytes from the bloodstream into solid tissue . In this study, we demonstrate that the blockade of lymphocyte extravasation potential mediates inhibition of certain cell-mediated immune responses in vivo . We investigated the effect of PT on the extravasation of antigen-primed lymphocytes into solid tissue . The results show that the loss of lymphocyte homing potential after in vitro treatment of the primed cells with PT is accompanied by an inhibition of antigen-specific contact hypersensitivity after adoptive transfer . This result suggests that the process of lymphocyte extravasation into nonlymphoid tissue sites such as the skin shares fundamental similarities to the selective localization of circulating lymphocytes to lymph nodes . Furthermore, the inhibition of contact hypersensitivity observed after the i.v . adoptive transfer of PT-treated antigen-primed cells could be circumvented by transferring the PT-treated cells directly into a tissue site with the relevant antigen . In contrast, no inhibition in the number of antibody-forming cells present within the spleen was observed after an adoptive transfer of PT-treated sheep red blood cell-primed lymphocytes, a result that is in agreement with radiotracer data . Thus, the inhibitory effect of PT on the adoptive transfer of contact hypersensitivity was established to be a direct result of the PT-mediated alteration of cellular migration, because PT inhibits the entrance of lymphocytes into specific tissue sites without inhibiting other cellular functions . This conclusion is additionally supported by experiments that showed that lymphocytes that have been pretreated with PT exhibit normal in vitro responses, as assayed by mitogenesis in response to concanavalin A and by the differentiation and function of alloantigen stimulated or hapten-specific cytotoxic T lymphocytes.(ABSTRACT TRUNCATED AT 400 WORDS)

J Clin Microbiol, 1985 May, 21(5), 838 - 9
Unusual bacterium, group Ve-2, causing peritonitis in a patient on continuous ambulatory peritoneal dialysis; Silver MR et al.; We report a case of peritonitis in a continuous ambulatory peritoneal dialysis patient with an unusual bacterium known as group Ve-2 . This is the first reported case of peritonitis attributable to this organism and only the second well-documented case of infection with this organism in the English literature.

J Bacteriol, 1985 May, 162(2), 752 - 5
Presence of 2-methylthioribosyl-trans-zeatin in Azotobacter vinelandii tRNA; Ajitkumar P et al.; Hydroxylated cytokinin, 2-methylthio-N6-(4-hydroxy-3-methylbut-2-enyl) adenosine, was found in the tRNA of Azotobacter vinelandii . This cytokinin had the trans configuration, unlike the cis configuration reported for that from other bacteria . Culture-condition-dependent changes in the content of this thiocytokinin and a few other thionucleosides in the tRNA of this bacterium have been observed.

J Dent Res, 1985 May, 64(5), 793 - 8
Rapid identification of periodontal pathogens in subgingival plaque: comparison of indirect immunofluorescence microscopy with bacterial culture for detection of Actinobacillus actinomycetemcomitans; Bonta Y et al.; The sensitivity of indirect immunofluorescence microscopy using specific polyclonal or monoclonal serodiagnostic reagents for Actinobacillus actinomycetemcomitans in subgingival dental plaque ranged from 82-100% as compared with culture on selective or non-selective media . This bacterium was found in 100% of the periodontally diseased sites examined in localized juvenile periodontitis patients and was statistically related to clinical indices of periodontal disease including the Gingival Index, Plaque Index, and Pocket Depth . Indirect immunofluorescence microscopy is a useful technique for the rapid and reliable determination of A . actinomycetemcomitans in human subgingival dental plaque which may be applied to the clinical diagnosis, treatment, and monitoring of periodontitis associated with A . actinomycetemcomitans.

Arch Microbiol, 1985 May, 141(4), 273 - 8
The major soluble cytochromes of the obligately aerobic sulfur bacterium, Thiobacillus neapolitanus; Trudinger PA et al.; Four cytochromes were isolated from soluble extracts of the aerobic sulfur bacterium, Thiobacillus neapolitanus . The two most abundant proteins were purified to homogeneity and thoroughly characterized . Cytochrome c-554 (547) is a monomeric, small molecular weight protein which is unusual in having two well-resolved alpha peaks in UV-visible absorption spectra . The redox potential is 208 mV . Native cytochrome c-549 is oligomeric, but has a subunit size of about 26,000 . The yield of this protein could be improved dramatically by washing membranes with 30% ammonium sulfate, but the material solubilized by this method had a larger native molecular weight than that in the initial 0.1 M Tris-Cl extract and behaved differently on chromatography . The properties of cytochrome c-549 including subunit size and UV-visible absorption spectra are similar to mitochondrial cytochrome c1 and chloroplast cytochrome f, which suggests that it may be a modified form of the predominant membrane cytochrome . Based on cytochrome content, it is suggested that T . neapolitanus is not closely related to other thiobacilli.

Arch Biochem Biophys, 1985 May 1, 238(2), 373 - 7
Identification of the components of a putative cytochrome bc1 complex in Rhodopseudomonas viridis; Wynn RM et al.; Chromatophore membranes isolated from the bacteriochlorophyll b-containing, photosynthetic purple nonsulfur bacterium, Rhodopseudomonas viridis, have been shown to contain a Rieske iron-sulfur protein, a cytochrome similar to cytochrome c1, and also at least one b-type cytochrome . These observations suggest the presence of a previously undetected cytochrome bc1 complex in this bacterium.

J Bacteriol, 1985 May, 162(2), 804 - 9
Molecular and regulatory properties of glutamine synthetase from the phototrophic bacterium Rhodopseudomonas capsulata E1F1; Caballero FJ et al.; The glutamine synthetase of the phototrophic bacterium Rhodopseudomonas capsulata E1F1 was purified to homogeneity by a procedure which used a single affinity chromatography step . Like enzymes from other photosynthetic procaryotes, native glutamine synthetase from R . capsulata E1F1 was found to be a dodecameric protein of approximately 660 kilodaltons with identical subunits of about 55 kilodaltons each . The Stokes radius and S20,w of the native enzyme were 8.35 nm and 19.20, respectively . The enzyme exhibited different aggregation states with detectable oligomers of 1, 2, 3, 4, 6, 8, 10, and 12 subunits . Disaggregation of the glutamine synthetase occurred after the native protein was subjected to electrophoresis in polyacrylamide gels, as well as occurring spontaneously at low ionic strength . Glutamine synthetase from R . capsulata E1F1 was regulated by an adenylylation-deadenylylation mechanism, and the adenylylation state of the protein depended on the nitrogen source, growth phase, and light intensity . Ammonia repressed glutamine synthetase, whereas glycine, serine, alanine, valine, and aspartate were noncompetitive inhibitors of the glutamine synthetase biosynthetic activity.

J Bacteriol, 1985 May, 162(2), 584 - 90
DNA transfer occurs during a cell surface contact stage of F sex factor-mediated bacterial conjugation; Panicker MM et al.; Donor bacteria containing JCFL39, a temperature-sensitive traD mutant of the F sex factor, were used at the nonpermissive temperature to accumulate stable mating pairs with recipient cells . At this stage in conjugation, extracellular F pili were removed by treatment with 0.01% sodium dodecyl sulfate . Upon then shifting to the permissive temperature for JCFL39, transfer of the F plasmid was observed . The mating pairs that were accumulated with JCFL39 at the nonpermissive temperature were readily observed by electron microscopy in wall-to-wall contact with the recipient bacteria . These results demonstrate that the traD product, which is known to be required in transferring DNA to a recipient bacterium, acts after the stage at which extracellular F pili are required . In addition, we concluded that DNA transfer takes place while donor and recipient cells are in surface contact and not necessarily through an extended F pilus as envisioned in some models of bacterial conjugation.

Am J Vet Res, 1985 Apr, 46(4), 804 - 7
Treatment of acute ocular Moraxella bovis infections in calves with a parenterally administered long-acting oxytetracycline formulation; Smith JA et al.; Acute ocular Moraxella bovis infections were induced in the UV-irradiated eyes of 10 calves . Eight calves developed corneal ulcers in at least 1 eye and were used for the treatment experiment . One randomly selected group of 4 calves with corneal ulcers and M bovis infections in 7 eyes was given a long-acting oxytetracycline formulation in 2 IM dosages of 20 mg/kg of body weight each, 72 hours apart . The other 4 calves with corneal ulcers in 6 eyes and M bovis in all 8 eyes served as nontreated controls . Bilateral ocular cultures were obtained and clinical observations were made daily for 20 days after treatment . After administration of the long-acting drug, new ulcers did not develop in the treated calves, whereas 5 new ulcers developed in the control-group calves during this time . The average durations of increased lacrimation/ulcerated eye were 2 and 12 days after treatment in the treatment and control groups, respectively; the average durations of blepharospasm were 3 and 8 days, respectively . Moraxella bovis was not isolated from any of the eyes of the treatment-group calves for the first 6 days after the antibiotic was administered, but was isolated from 1 eye of 1 treated calf on posttreatment day 7 and daily thereafter, for a total of 14 positive cultures of 160 ocular cultures obtained from the treatment-group calves after treatment . The bacterium was isolated from all eyes and from 144 of 160 cultures from the control-group calves during this time.

Appl Environ Microbiol, 1985 Apr, 49(4), 975 - 80
Photoreactivation of UV-irradiated Legionella pneumophila and other Legionella species; Knudson GB; Shortwave UV light was assessed as a feasible modality for the control of Legionnaires disease bacterium in water . The results of this study show that Legionella pneumophila and six other Legionella species are very sensitive to low doses of UV . However, all Legionella species tested effectively countered the germicidal effect of UV when subsequently exposed to photoreactiving light.

Arch Biochem Biophys, 1985 Apr, 238(1), 97 - 110
Active transport of nonpolar amino acids in Chromatium vinosum; Cobb AD et al.; The photosynthetic purple sulfur bacterium, Chromatium vinosum, takes up the amino acids, L-phenylalanine and L-leucine, via two apparently different electrogenic, H+/amino acid symports . Na+ serves as an allosteric modulator for leucine transport, lowering the Km for leucine from 66 to 15 microM . C . vinosum cells also contain a system that transports both isoleucine and valine . The isoleucine/valine system has the attributes of a H+/amino acid symport at pH less than 7.5 but appears to function as a H+/Na+ (Li+)/amino acid symport at pH greater than or equal to 7.5 . Na+ gradients produce an allosteric lowering of the Km values for both isoleucine and valine, from 14 to 7 microM and from 34 to 17 microM, respectively . C . vinosum also accumulates D-alanine in an energy-dependent reaction . The transport process appears to involve the electrogenic cotransport of D-alanine and Na+ . The Km value for D-alanine was determined to be 9 microM . Unlike the previously characterized C . vinosum L-alanine/Na+ symport, Na+ gradients did not affect the Km for D-alanine transport . L-Alanine and glycine, but not alpha-aminoisobutyric acid, act as competitive inhibitors for D-alanine transport.

J Bacteriol, 1985 Mar, 161(3), 1146 - 55
Differential expression of protein S genes during Myxococcus xanthus development; Downard JS et al.; Protein S, the most abundant protein synthesized during development of the fruiting bacterium Myxococcus xanthus, is coded by two highly homologous genes called protein S gene 1 (ops) and protein S gene 2 (tps) . The expression of these genes was studied with fusions of the protein S genes to the lacZ gene of Escherichia coli . The gene fusions were constructed so that expression of beta-galactosidase activity was dependent on protein S gene regulatory sequences . Both the gene 1-lacZ fusion and the gene 2-lacZ fusion were expressed exclusively during fruiting body formation (development) in M . xanthus . However, distinct patterns of induction of fusion protein activity were observed for the two genes . Gene 2 fusion activity was detected early during development on an agar surface and could also be observed during nutritional downshift in dispersed liquid culture . Gene 1 fusion activity was not detected until much later in development and was not observed after downshift in liquid culture . The time of induction of gene 1 fusion activity was correlated with the onset of sporulation, and most of the activity was spore associated . This gene fusion was expressed during glycerol-induced sporulation when gene 2 fusion activity could not be detected . The protein S genes appear to be members of distinct regulatory classes of developmental genes in M . xanthus.

J Reprod Med, 1985 Mar, 30(3 Suppl), 279 - 83
A nonculture test for identification of Chlamydia trachomatis; Amortegui AJ et al.; PIP: The standard isolation test for Chlamydia trachomatis involves growth of C . trachomatis in cycloheximide-treated McCoy cells, but isolation is expensive and complicated and requires special equipment, knowledge, and at least 48 hours . A recent approach to a simple, accurate, and inexpensive test without isolation involves use of enzyme immunoassays . In March 1984, the Chlamydiazyme assay from Abbott Laboratories which detects chlamydial antigens in cervical and urethral swab specimens, was tested in 209 abortion patients in Pittsburgh . 2 swab speicmens were obtained from each patient, 1 to be analyzed for C . trachomatis antigens with Chlamydiazyme and 1 to be used for chlamydial isolation tests . 80% of the patients were white and 70% were unmarried . Their ages ranged from 18-38 years with a mean age of 24.4 years . 72 had had urogenital symptoms within the preceding month . C . trachomatis was isolated in McCoy cells after subculturing from 18 of 209 patients (8.6%) . C . trachomatis antigens were found with Chlamydiazyme in 13 of 18 patients (72.2%) whose specimens yielded the bacterium . The specificity of the enzyme immunoassay procedure was 98.4% (188 of 191) . Overall, 201 of 209 samples (96.2%) were identified correctly with Chlamydiazyme, as compared to isolation after subculture . Of the 18 isolates, only 13 were positive on primary isolation and 5 grew on subsequent subculture . 10 of the 13 primary isolate specimens and 3 of the 5 which grew on subculture were reactive with Chlamydiazyme . The same number of infections was detected with Chlamydiazyme and primary isolation, although only 10 of 13 patients were positive with both methods . 3 specimens were reactive with Chlamydiazyme although organisms were not isolated . 2 of the 3 patients had vaginal discharge . 2 of the 3 were recultured within 6 weeks and both yielded positive Chlamydiazyme results in the absence of C . trachomatis isolation . It was considered unlikely that C . trachomatis would be isolated since all patients had received prophylactic tetracycline treatment after the abortion procedures .

Radiobiologiia, 1985 Mar-Apr, 25(2), 258 - 60
{A method of estimating the effectiveness of ionizing radiation and magnetic fields for phage induction in lysogenic bacterial culture}; Anosova MG et al.; Either the difference delta N of the content of free phage particles in the experiment and the control or K ratio of these values can be used to estimate the effectiveness of ionizing radiation or other agents inducing phage formation in a lysogenic bacterium culture . The estimation technique the results of which are nearly independent of the fluctuations in the number of phage particles in the control, the inductor dose being invariable, is the most adequate one . The induction of phage in E . coli K12 (lambda) culture by X-rays and magnetic field is an example illustrating that the K ratio, which can be called "the induction coefficient", is in a good agreement with the requirement mentioned above . A possible nature of the phenomenon observed is discussed.

Biochimie, 1985 Mar-Apr, 67(3-4), 343 - 7
The SOS system; d'Ari R; In the bacterium Escherichia coli DNA damaging treatments such as ultraviolet or ionizing radiation induce a set of functions called collectively the SOS response, reviewed here . The regulation of the SOS response involves a repressor, the LexA protein, and an inducer, the RecA protein . After DNA damage an effector molecule is produced--possibly single stranded DNA--which activates the RecA protein to a form capable of catalysing proteolytic cleavage of LexA . The repressors of certain temperate prophages are cleaved under the same conditions, resulting in lysogenic induction . SOS functions are involved in DNA repair and mutagenesis, in cell division inhibition, in recovery of normal physiological conditions after the DNA damage is repaired, and possibly in cell death when DNA damage is too extensive . The SOS response also includes several chromosomal genes of unknown function, a number of plasmid encoded genes (bacteriocins, mutagenesis), and lysogenic induction of certain prophages . DNA damaging treatments seem to induce DNA repair and mutagenic activities and proviral development in many species, including mammalian cells . In general, substances which are genotoxic to higher eukaryotes induce the SOS response in bacteria . This correlation is the basis of the numerous bacterial tests for genotoxicity and carcinogenicity.

Eur J Biochem, 1985 Feb 15, 147(1), 47 - 52
Identification of the major human sialoglycoprotein from red cells, glycophorin AM, as the receptor for Escherichia coli IH 11165 and characterization of the receptor site; Jokinen M et al.; The pyelonephritogenic Escherichia coli strain 1 H 11165 specifically agglutinates human erythrocytes carrying the M blood group antigen . The polymorphic forms of this antigen, M and N, are located in the NH2-terminal region of the major human red-cell sialoglycoprotein, glycophorin A . Radioactively labeled glycophorin A from M cells specifically bound to the bacteria . Purified glycophorin AM, but not glycophorin AN, efficiently inhibited for binding . Mild periodate treatment oxidized the NH2-terminal serine in glycophorin AM and this resulted in loss of binding to the bacteria . High concentrations of serine and alkali-labile oligosaccharides derived from glycophorin AM inhibited the binding, whereas the synthetic M-specific NH2-terminal pentapeptide Ser-Ser-Thr-Thr-Gly did not . Neuraminidase treatment of glycophorin AM did not destroy the binding . The most efficient inhibition of binding was observed with the N-terminal glyco-octapeptide obtained from glycophorin AM by CNBr cleavage . This peptide contains both the essential serine residue and the alkali-labile oligosaccharides, which both are recognized by the bacterium.

J Bacteriol, 1985 Feb, 161(2), 750 - 7
Three-dimensional architecture of the cell sheath and septa of Methanospirillum hungatei; Shaw PJ et al.; The methanogenic bacterium Methanospirillum hungatei exists as filaments which have a very unusual cell wall architecture, comprising a long cylindrical sheath within which there may be many individual cells arranged in a line . The sheath has a two-dimensional crystalline structure, and the cells are separated within the tube by septa which also have a crystalline structure . We have used computer image processing of tilted-view electron micrographs to analyze the structure in negative stains of both of these components in three dimensions . The repeating unit of the sheath consists of four approximately spherical domains ca . 2.5 nm in diameter arranged in a row . Based on observations of the type of lattice imperfections that occur, we suggest that each of the domains represents a separate polypeptide subunit and that the subunits are incorporated into the wall one by one . The septa are circular plates of remarkably constant size . They are normally found as double layers . They are hexagonally symmetrical and consist of trimerically associated subunits which interact about dimer axes to form an open network containing large pores ca . 15 nm in diameter.

J Cell Sci, 1985 Feb, 73, 389 - 98
Isolation and characterization of macronuclei of Paramecium caudatum infected with the macronucleus-specific bacterium Holospora obtusa; Freiburg M; Macronuclei from Paramecium caudatum infected with Holospora obtusa may be isolated on sucrose step gradients . Macronuclei containing primarily infectious forms can be separated from those bearing predominantly reproductive forms . RNA polymerase activity in infected macronuclei is greater by a factor of 5 than that in uninfected macronuclei . Proteinase activity is also significantly higher.

Antibiot Med Biotekhnol, 1985 Feb, 30(2), 109 - 13
{Effect of lipopolysaccharide of the pseudotuberculosis bacterium on the functional activity of macrophages}; Kuznetsova TA et al.; Study of the effect of lipopolysaccharide (LPS) of Y . pseudotuberculosis on the culture of peritoneal macrophages of guinea pigs has established that in concentrations of 1-10 micrograms/ml LPS stimulated the absorption and digestive activity of the macrophages . In concentrations of 50-100 micrograms/ml it had a cytotoxic effect on the cell elements and inhibited their phagocytic function . The study of the LPS effect on absorption and liberation of 14C-labeled bacteria of Y . pseudotuberculosis showed that the biopolymer increased 2-3 times the uptake of the labeled antigen from the macrophages and lowered its elimination . In the experiments on mice infected with a labeled culture of S . aureus no increase in the uptake under the effect of the pseudotuberculosis LPS was observed, whereas an increase in the rate of the label elimination was stated . The difference was statistically significant . The results of the experiments are indicative of the specific effect of LPS . The study demonstrated a significant role of LPS of Y . pseudotuberculosis in the pathogenesis and protection of the host from this infection.

J Exp Med, 1985 Feb 1, 161(2), 409 - 22
Isolation and characterization of the cytoplasmic and outer membranes of the Legionnaires' disease bacterium (Legionella pneumophila); Gabay JE et al.; Legionella pneumophila, the etiologic agent of Legionnaires' disease, is phagocytized in an unusual way and multiplies in human mononuclear phagocytes in a novel phagosome . As a first step toward understanding these L . pneumophila-phagocyte interactions, we have studied the envelope of L . pneumophila Philadelphia 1 strain . We isolated cell envelopes by treating whole bacterial cells with lysozyme and EDTA to convert them to spheroplasts, then lysing the spheroplasts osmotically or sonically . We resolved the cell envelopes into two membrane fractions by isopycnic centrifugation . We localized NADH oxidase to the fraction of buoyant density 1.145, which we designated cytoplasmic membrane, and lipopolysaccharide (LPS) to the fraction of density 1.222, which we designated outer membrane . Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) revealed that the L . pneumophila outer membrane contains a single major protein species migrating at 28,000 mol wt; this is the major protein of the bacterium . The cytoplasmic membrane also contains a single major protein species migrating at 65,000 mol wt . Surface iodination of the bacteria and agglutination and immunofluorescence studies with rabbit antibody produced against the purified major outer membrane protein (MOMP) revealed that this protein is exposed at the cell surface . We isolated LPS from L . pneumophila membranes by SDS-EDTA treatment . The pattern obtained by subjecting the LPS to SDS-PAGE and staining the gel with silver nitrate suggests that L . pneumophila LPS might be atypical . We studied patient serologic responses to cell envelope components of L . pneumophila Philadelphia 1, a serogroup 1 organism . Sera from patients with evidence of infection with serogroup 1 L . pneumophila contained large amounts of antibody to this strain . Few of these antibodies recognized the MOMP of L . pneumophila . In contrast, greater than 98% of these antibodies were directed against the LPS . This indicates that LPS is the dominant serogroup antigen and the major antigen responsible for the reactivity of patient sera in the indirect fluorescent antibody assay, currently the principal diagnostic assay for Legionella infection.

J Bacteriol, 1985 Feb, 161(2), 810 - 2
Induction of chloramphenicol and tetracycline resistance in Flexibacter sp . strain FS-1; Barcak GJ et al.; The gliding bacterium Flexibacter sp . strain FS-1 exhibits inducible resistance to chloramphenicol (Cmr) and tetracycline (Tcr) . Either chloramphenicol or tetracycline alone induced a Cmr Tcr phenotype . The resistance is apparently not plasmid encoded.

Biochem Biophys Res Commun, 1985 Jan 31, 126(2), 698 - 704
Heterologous hybridization of ribulose 1,5-bisphosphate carboxylase/oxygenase (RuBisCO) restores the enzyme activities; Incharoensakdi A et al.; The catalytic core (A8) and small subunit (B) of ribulose 1,5-bisphosphate carboxylase/oxygenase (RuBisCO) were isolated from two species of cyanobacteria (Aphanothece halophytica and Synechococcus ACMM 323) as well as from the photosynthetic purple sulfur bacterium, Chromatium vinosum . The subunit B is essential for the activity of all three enzymes . The heterologous hybridization of RuBisCO molecules from the three organisms was attempted and the reconstitution of the catalytically active hybrid was achieved between A8 derived from either Aphanothece or Synechococcus and subunit B from Aphanothece, Synechococcus or Chromatium . However, reconstitution of the enzymically active hybrid between A8 from Chromatium and B subunits from the cyanobacteria could not be achieved . Experiments by using high performance liquid column chromatography also showed the formation of a heterologous hybrid possessing RuBP carboxylase activity.

Biochem Biophys Res Commun, 1985 Jan 31, 126(2), 685 - 91
Evidence of tyrosine kinase activity in the photosynthetic bacterium Rhodospirillum rubrum; Vallejos RH et al.; The photosynthetic bacterium Rohodospirillum rubrum evidenced tyrosine protein phosphorylation under photoautotrophic conditions in the presence of {32P}Pi . The stability to alkaline treatment of the {32P} bound to the cell-free extract proteins suggested that tyrosine residues were carrying the labelling . One- and two-dimensional high voltage paper electrophoresis analysis revealed that such extracts do contain {32P}-phosphotyrosine residues . Furthermore, the association of alkali stable {32P} bound to specific proteins of the cell-free extract was confirmed by sodium dodecyl sulfate polyacrylamide gel electrophoresis combined with KOH treatment of the gel . A definite argument in favor of protein kinase(s) phosphorylating tyrosine residues in R.rubrum proteins was obtained by partial purification of a tyrosine kinase activity from cell-free extract capable of phosphorylating synthetic peptides that only contain a single tyrosine residue as phosphate acceptor.

Biochem J, 1985 Jan 15, 225(2), 441 - 8
The methane mono-oxygenase reaction system studied in vivo by membrane-inlet mass spectrometry; Joergensen L; A membrane-inlet mass spectrometer connected to an open-system cuvette was used for direct measurement of dissolved methane and O2 in bacterial samples of strain OU-4-1, a type II methanotrophic bacterium . A technique was applied for keeping the concentration of dissolved methane or O2 in the sample constant while the concentration of the other dissolved gas was varied . This allowed the reaction mechanism of methane mono-oxygenase to be studied in vivo . The enzyme was found to follow a random bi-reactant mechanism with respect to binding of methane and O2 . Binding of one substrate decreased the affinity for the other . The true binding constants were 1 microM for methane and 0.14 microM for O2 . Studies of HCN inhibition confirmed the random bi-reactant mechanism . HCN was found to be a non-exclusive inhibitor with a binding constant of 0.4 microM.

FEBS Lett, 1985 Jan 7, 179(2), 208 - 12
Purification of arogenate dehydrogenase from Phenylobacterium immobile; Mayer E et al.; Phenylobacterium immobile, a bacterium which is able to degrade the herbicide chloridazon, utilizes for L-tyrosine synthesis arogenate as an obligatory intermediate which is converted in the final biosynthetic step by a dehydrogenase to tyrosine . This enzyme, the arogenate dehydrogenase, has been purified for the first time in a 5-step procedure to homogeneity as confirmed by electrophoresis . The Mr of the enzyme that consists of two identical subunits amounts to 69000 as established by gel electrophoresis after cross-linking the enzyme with dimethylsuberimidate . The Km values were 0.09 mM for arogenate and 0.02 mM for NAD+ . The enzyme has a high specificity with respect to its substrate arogenate.

Nature, 1985 Jan 3-9, 313(5997), 22 - 7
RNA polymerase heterogeneity in Streptomyces coelicolor; Westpheling J et al.; Two forms of RNA polymerase holoenzyme have been identified in the filamentous differentiating bacterium Streptomyces coelicolor . They contain different species of sigma factor and are distinguishable by their ability to recognize different promoter classes . These and other holoenzyme forms may in part determine the selective expression of different gene sets in this morphologically-complex bacterium.

Adv Exp Med Biol, 1985, 189, 107 - 27
Immunological aspects of type 1 and 2 diabetes mellitus; Lernmark A et al.; IDDM occurs predominantly among individuals being class II antigen HLA-DR 3 and/or 4 positive, while NIDDM is not associated with HLA-D . Although the HLA-DR 3 or 4 specificities are prerequisites for IDDM to develop, their high frequencies (about 60%) in the background population preclude tissue typing as a predictive test, underlined by the observation that less than 50% of monozygotic twins are concordant for IDDM . The presence of a number of immune abnormalities argues that the causes of IDDM may be sought in an altered immune reaction against antigens present in the pancreatic B cells and/or in the environment . The majority of IDDM patients of short duration show both cellular and humoral autoimmunity against the pancreatic B cells . Similar phenomena may be observed in patients initially diagnosed as NIDDM and treated with oral hypoglycemic agents . It has been speculated that these patients have a retarded form of IDDM . It is possible that the combination of specific Class II antigen molecule(s) and an invading antigen (virus, bacterium, chemical etc.) presented to the immune system triggers the formation of effector cells such as B lymphocytes and cytotoxic T lymphocytes which also cross-react with the pancreatic B cells . Multiple exposures to this or related antigens throughout several years may eventually lead a sufficient loss of pancreatic B cells to cause insulin dependence.

J Lab Clin Med, 1985 Jan, 105(1), 124 - 31
Effect of prior influenza virus infections on susceptibility of AKR/J mice to respiratory challenge with Legionella pneumophila; Berendt RF et al.; Influenza virus administered intranasally to AKR/J mice, followed 3 days later by Legionella pneumophila inoculated intranasally, caused significantly greater mortality than did either of the two agents administered alone . Viable concentrations of both bacteria and viruses dropped in sequentially infected animals, despite the ultimate fatal outcome . Viral concentrations, however, did not decrease as rapidly in sequentially infected as in singly infected mice . Histopathologic lesions were consistent with viral replication aided by elaboration of a bacterial toxin . This observation contrasts with the more commonly observed sequence in which the bacterium proliferates after the virus interferes with host defense . Cell-free preparations were found to have toxic activity.

Infect Immun, 1985 Jan, 47(1), 301 - 5
Effect of local and parenteral immunization on implantation of Actinomyces viscosus T6 in rats; Olsson J et al.; Groups of rats immunized in the vicinity of the major salivary glands or immunized intraperitoneally with Actinomyces viscosus T6 and their sham-immunized controls were infected with the homologous bacterium . Significantly higher levels of salivary and serum antibody were induced by intraperitoneal than by salivary gland immunization . There were also significant inverse correlations between the levels of salivary and serum antibody and the levels of implantation of A . viscosus T6 . The level of implantation of A . viscosus T6 was significantly lower in the immunized animals than in the controls . However, antibody had limited capacity to inhibit the establishment of this bacterium.

Gene, 1985, 34(2-3), 219 - 26
Broad-host-range plasmid vector for the in vitro construction of transcriptional/translational lac fusions; Nano FE et al.; A broad-host-range plasmid was constructed that allows the in vitro formation of beta-galactosidase fusions . DNA from the photosynthetic bacterium Rhodopseudomonas sphaeroides was cloned into this plasmid and a number of R . sphaeroides isolates were recovered that had varying levels of beta-galactosidase activity . beta-galactosidase antigenic activity from the fusion strains could be localized immunologically in polypeptides with an Mr of 120 000 or greater . Expression of beta-galactosidase activity under control of fusion derivatives was either very low or nonexistent in Escherichia coli relative to R . sphaeroides, indicating that R . sphaeroides promoters or translational start signals function poorly in E . coli.

Prep Biochem, 1985, 15(5), 321 - 34
Purification of hydrogenase by fast protein liquid chromatography and by conventional separation techniques: a comparative study; Kovacs KL et al.; Hydrogenase was purified from the photosynthetic bacterium Thiocapsa roseopersicina to homogeneity by various methods . Conventional techniques included separation of the crude protein extract on Phenyl-Sepharose CL 4B, DEAE-cellulose DE52, and chromatofocusing columns or on preparative polyacrylamide gel-electrophoresis . The same protein was isolated by fast protein liquid chromatography (FPLC) in two steps . Comparison of the two different approaches clearly show the superiority of the FPLC method both in enzyme recovery yield and in time requirement.

Crit Rev Clin Lab Sci, 1985, 21(4), 323 - 81
Legionella and Legionnaires' disease: a review with emphasis on environmental studies and laboratory diagnosis; Winn WC Jr; Legionella pneumophila and related species are important causes of epidemic bacterial pneumonia and nosocomial infection . This review will discuss this new family of bacteria and the diseases they produce . The classification, general microbiologic characteristics, and ecology of the bacteria will be reviewed and the epidemiology and clinical aspects of the infection will be discussed . More emphasis will be given to issues that are more directly related to laboratory workers and with which the author has had more direct experience: pathology, laboratory diagnosis of human infection, pathogenesis of the infection, and virulence mechanisms of the bacterium . Therapy and prevention of the infection will be discussed more briefly.

Arch Oral Biol, 1985, 30(3), 291 - 4
Peptidoglycan from the potentially pathogenic oral bacterium Actinomyces viscosus is a B-cell mitogen; Baker JJ; Cell walls and peptidoglycan from Actinomyces viscosus, strain M-100 were compared for their ability to act as mitogens with spleen cells from germ-free Fischer rats . The cell walls were prepared from trypticase soy broth grown whole cells using a French press, followed by two consecutive washes with 0.1 M tris-HCl buffer, pH 8.0, 1 M NaCl and distilled water . Peptidoglycan was prepared from cell walls by three consecutive formamide extractions at 165 degrees C . On a dry-weight basis, the peptidoglycan was a significantly-better mitogen than cell walls, suggesting that the peptidoglycan is the major mitogenic component of A . viscosus cell walls . Mononuclear spleen cells were separated on a Nylon-wool column into a non-adherent subpopulation enriched for T lymphocytes and a weakly-adherent, plunger-removable subpopulation enriched for B lymphocytes . The non-adherent T-cell subpopulation responded strongly to the T-cell mitogen PHA, but was unresponsive to both the peptidoglycan and cell walls from A . viscosus . In contrast, the weakly-adherent enriched B-cell subpopulation was less responsive to PHA, but was strongly stimulated by A . viscosus peptidoglycan and cell walls . These results indicate that peptidoglycan and cell walls from A . viscosus are B-cell mitogens.

Prikl Biokhim Mikrobiol, 1985 Jan-Feb, 21(1), 114 - 21
{Bioluminescent method of determining picomolar amounts of nicotinamide-adenine dinucleotide using an immobilized extract of the luminescent bacterium Beneckea harveyi}; Lebedeva OV et al.; The luminous bacteria Beneckea Harveyi were immobilized on BrCN-sepharose and cellulose films activated with cyanuric chloride . Preparations with high luciferase and FMN-reductase activities were obtained, which showed no background luminescence without NADH being added . The storage conditions for the preparations obtained were optimized, and their kinetic parameters and thermostability were studied . Standard curves for NADH determining within the concentration range 1 nM-1 microM were plotted with the detection level of 1 picomol NADH . The preparations are very promising for bioluminescent assay due to their high activity, simple production, high stability during storage and a possibility for the repeated use.

Arch Oral Biol, 1985, 30(11-12), 855 - 8
The comparative cariogenicity and plaque-forming ability in vivo of four species of the bacterium Actinomyces in gnotobiotic rats; Shakespeare AP et al.; Gnotobiotic WAG/RIJ rats on a high sucrose diet were monoinfected with 12 strains of Actinomyces spp . Moderate levels of caries were induced by a single strain of Actinomyces naeslundii and low levels by two strains of Actinomyces viscosus, three strains of A . naeslundii and one strain of Actinomyces israelii . No caries was induced by single strains of A . viscosus and A . israelii or by three Actinomyces odontolyticus strains . Only fissure caries was observed . Scanning electron microscopy showed that all strains colonized the fissures and most colonized the lingual surface of the teeth, but to a limited extent . Production of abundant and dense plaque was not always accompanied by caries.

Arch Oral Biol, 1985, 30(9), 661 - 6
The mitogenicity for murine splenocytes of specific surface components of the oral periodontopathic bacterium, Actinomyces viscosus; Halfpap LM et al.; Many characterized fractions obtained from A . viscosus were examined to identify the macromolecules responsible for mitogenicity for lymphocytes . Spleen-cell suspensions of CBA/J mice were cultured with 50-200 micrograms dry weight of A . viscosus strains T14V and T14AV cellular components . Lipopolysaccharide (LPS) (Escherichia coli) was used as a positive control . Mechanical disruption with a French pressure cell or sonication produced preparations with a stimulation of 69,082 and 45,183 counts above background (CAB), respectively . Mitogenic activity was also present in the culture supernatant (38,000 CAB) . Other poorly mitogenic fractions included the peptidoglycan, cell-wall fractions, muramidase digests of cell walls, and the microcapsule extracted from whole cells with 0.5 M MgNO3 . The results suggest that mitogenic activity is not associated with the isolated cell-wall structure . The activity was released from the cell surface by physical shearing forces, as well as released into the medium growth.

Recent Results Cancer Res, 1985, 98, 135 - 41
Effect of intensive adjuvant chemotherapy on wound healing in 69 patients with osteogenic sarcomas of the lower extremities; Bertermann O et al.; Reported surgical adjuvant trials in humans have resulted in little clinically significant impairment of wound healing . Such trials are often carried out with subtherapeutic doses or with the drugs administered relatively late in the wound healing process . It is the objective of our study to investigate the effect of intensive pre- and postoperative chemotherapy (BCD, ADR, HD-MTX) on wound healing in patients with osteogenic sarcomas . Wound healing was defined in our study as lack of infection . In a series of 110 patients with osteogenic sarcomas we analyzed the data of 69 patients with lower extremity lesions: of these, 54 patients had distal femur lesions and 15 had upper tibia and fibula lesions . All the patients underwent en-bloc resections and insertion of a prosthetic device . Pre- and postoperative antibiotics were given routinely . In 80% of our patients (55/69) an uneventful postoperative course was recorded with respect to wound healing . None of these required a secondary operative procedure . Debridement of the wound or debridement of the wound followed by skin grafting had to be performed in 14% (10/69) of the patients . Most of the amputations were performed early in this series of cases . After secondary surgery wound healing was uneventful in most of the patients . No patient died as a consequence of wound infection . Mixed bacterial infections were found in 13/14 patients . No single specific bacterium could be identified . One patient developed a fungal infection (aspergillosis) . Eight infections were secondary to skin necrosis . In this series we later found the serious effects of the skin necrosis and slough could be reduced by early intervention with a muscle pedicle flap.(ABSTRACT TRUNCATED AT 250 WORDS)

Gene, 1985, 38(1-3), 233 - 7
A shuttle vector plasmid for studying carcinogen-induced point mutations in mammalian cells; Seidman MM et al.; We have constructed a shuttle vector plasmid for studying mutagenesis in mammalian cells . The plasmid replicates in cell lines permissive for SV40 virus as well as in the bacterium Escherichia coli and carries a bacterial suppressor tRNA gene (supF) that can serve as a mutagenesis marker . The plasmid replicates as efficiently as SV40 virus in African Green Monkey kidney CV1 cells, indicating that all traces of the inhibitory sequences normally found in pBR322 and its derivatives have been removed . The design of the plasmid and the small size of the mutagenesis target gene decrease the probability of recovering spontaneous deletion mutations that have been shown to occur at high frequency during passage in mammalian cells . The frequency of spontaneous-mutant plasmids recovered after passage in CV1 cells is substantially lower than with other vectors described previously . When the plasmid DNA is treated with UV radiation before passage in CV1 cells, mutants are observed at a frequency about 20-fold above the spontaneous background.

Gene, 1985, 34(2-3), 367 - 70
Cloning of a multicopy plasmid from the actinorhizad nitrogen-fixing bacterium Frankia sp . and determination of its restriction map; Normand P et al.; An 8.3-kb multicopy plasmid, pFQ31, from the nitrogen-fixing Frankia sp . strain ArI3, was cloned into Escherichia coli plasmid vectors and analysed physically . pFQ31 has no detectable sequence homology with another Frankia plasmid, pFQ32, which is present in the same host . Derivatives of pFQ31 with an antibotic resistance marker were introduced into Streptomyces lividans, which is taxonomically related to Frankia, but no stable replication could be achieved.

Acta Microbiol Pol, 1985, 34(1), 5 - 14
Autolysis of Caulobacter crescentus grown in the presence of glycine; Markiewicz Z et al.; Caulobacter crescentus was grown in complex medium supplemented with low (0.05%) concentration of glycine, a component of the murein peptide side chains of this bacterium . Murein synthesized in the presence of glycine was poorly crosslinked and the rate of its synthesis was slowed down compared to the control cells . The glycine-grown cells were considerably more sensitive to the chelating agent EDTA and Tris buffer than the control cells and also lysed faster when incubated with beta-lactam antibiotics . No changes in phospholipid composition in the presence of glycine were observed and the outer membrane protein composition of the glycine-grown cells was altered only in the amount of 130 000 protein which forms the surface array of C . crescentus . The effects of glycine can thus be tentatively put down to the reduced crosslinkage of murein synthesized in its presence.

Acta Microbiol Pol, 1985, 34(2), 121 - 9
Murein hydrolases of Caulobacter crescentus; Markiewicz Z; Caulobacter crescentus was found to exhibit a similar autolytic response to a variety of factors affecting the structure of the cell envelope and interfering with murein synthesis as several other species of bacteria . Autolysis was accompanied by the hydrolysis of murein with the release of soluble degradation products . Several murein hydrolases with different bond specificity were found and except for the absence of DD-carboxypeptidase and LD-carboxypeptidase activities the make-up of these enzymes resembled that of the well studied bacterium Escherichia coli.

Biochem Biophys Res Commun, 1984 Dec 28, 125(3), 1025 - 32
A cytoplasmic nickel-iron hydrogenase with high specific activity from Desulfovibrio multispirans sp . N., a new species of sulfate reducing bacterium; Czechowski MH et al.; A hydrogenase from a new species of sulfate reducing bacterium has been isolated and characterized . In contrast to other hydrogenases isolated from Desulfovibrio, this enzyme is found in the cytoplasmic fraction rather than in the periplasm . The specific activity of the enzyme, as measured in the hydrogen evolution assay, is twice as high as the specific activity of the hydrogenase from D . gigas . It also differentiates itself from the periplasmic Desulfovibrio hydrogenases by being more active in the hydrogen evolution rather than in the hydrogen uptake assay . The enzyme was shown to contain 0.9 atoms of nickel, 11 atoms of iron and 10 atoms of labile sulfide per mole of enzyme . It exhibits an unusually low intensity of the g = 2.31 nickel EPR signal in the isolated enzyme but shows a normal intensity for the g = 2.19 nickel EPR signal when reduced under hydrogen.

J Biol Chem, 1984 Dec 25, 259(24), 15502 - 8
Purification and properties of the activating enzyme for iron protein of nitrogenase from the photosynthetic bacterium Rhodospirillum rubrum; Saari LL et al.; The oxygen-labile, activating enzyme for iron protein from the photosynthetic bacterium, Rhodospirillum rubrum, was purified 11,800-fold using a combination of chromatophore washing, DE52-cellulose chromatography, hydroxylapatite chromatography, reactive red-120 cross-linked agarose chromatography, reactive red-120 cross-linked agarose chromatography, and Sephadex G-75 gel filtration . Activating enzyme appeared homogeneous on silver-stained sodium dodecyl sulfate-polyacrylamide gels, and the staining intensity of the activating-enzyme band was correlated with the activating-enzyme activity observed in in vitro assays . Either formaldehyde fixation or higher acrylamide concentration was required to accurately assess the purity of activating enzyme on silver-stained gels . Activating enzyme was stable for 30 days at 4 degrees C . Dithiothreitol was a necessary component for the stability of partially purified activating enzyme . NaCl inhibited the coupled assay for activating enzyme . The pI of activating enzyme was determined to be 6.5 . Activating enzyme is composed of a minimum of 336 amino acids and a minimum calculated Mr is 32,032 . The Mr of activating enzyme was estimated to be 21,700 by analytical gel filtration and 32,800 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis . An absorption maximum at 280 nm was observed for the activating enzyme.

J Biol Chem, 1984 Dec 10, 259(23), 14458 - 62
Molecular structure of trimethylamine dehydrogenase from the bacterium W3A1 at 6.0-A resolution; Lim LW et al.; An electron density map of trimethylamine dehydrogenase has been calculated at 6.0-A resolution . Protein phases were based on two isomorphous mercury derivatives with similar binding properties, and on anomalous scattering measurements . The map has been averaged about the noncrystallographic 2-fold axis, plotted on transparent sheets and used to construct a wooden model . The elipsoidal dimer has a large inter-subunit interface . Each subunit appears to contain three closely associated domains with the iron-sulfur cluster located between two of them . The map suggests an alpha/beta-structure for two of the domains and a large helix content for the third.

FEBS Lett, 1984 Dec 10, 178(2), 343 - 50
Two distinct quinone-modulated modes of antimycin-sensitive cytochrome b reduction in the cytochrome bc1 complex; Robertson DE et al.; Reduction of cytochrome b-560 (analogous to cyt b-562 of mitochondria) via an antimycin-sensitive route has been revealed in chromatophores of the photosynthetic bacterium, Rhodopseudomonas sphaeroides Ga . Indeed, the results suggest that two reductive mechanisms can be operative . One is consistent with the idea that the quinol generated at the reaction center QB site enters the Q pool and, via the Qc site, equilibrates with cytochrome b-560 . The other reductive mode circumvents redox equilibrium with the pool; we consider that this could result from a direct encounter of the reaction center with the bc1 complex perhaps involving a direct QB-Qc site interaction . This latter reaction is suppressed by occupancy of the Qc site, not only by antimycin but by ubiquinol and ubiquinone.

J Mol Biol, 1984 Dec 5, 180(2), 385 - 98
X-ray structure analysis of a membrane protein complex . Electron density map at 3 A resolution and a model of the chromophores of the photosynthetic reaction center from Rhodopseudomonas viridis; Deisenhofer J et al.; X-ray analysis of three-dimensional crystals of the photosynthetic reaction center from the purple bacterium Rhodopseudomonas viridis led to an electron density distribution at 3 A resolution calculated with phases from multiple isomorphous replacement . The protein subunits of the complex were identified . An atomic model of the prosthetic groups of the reaction center complex (4 bacteriochlorophyll b, 2 bacteriopheophytin b . 1 non-heme iron, 1 menaquinone, 4 heme groups) was built . The arrangement of the ring systems of the bacteriochlorophyll b and bacteriopheophytin b molecules shows a local 2-fold rotation symmetry; two bacteriochlorophyll b form a closely associated, non-covalently linked dimer ("special pair") . A different local 2-fold symmetry axis is observed for the heme groups of the cytochrome part.

Biophys J, 1984 Dec, 46(6), 781 - 6
Dispersal of motile bacteria from a plane layer; Cridland JV et al.; The dispersal of an initially well-defined concentration of the motile bacterium Escherichia coli was measured under nonchemotactic conditions . The distribution of bacteria along a glass observation cell was measured by recording the intensity of light scattered by the organisms . For comparison, the diffusion of fluorescein was also measured by determining the distribution of fluorescence throughout the observation cell . The dispersal of bacteria from a plane layer, under nonchemotactic conditions, can be adequately described by the Gaussian solution of the diffusion equation.

Can J Microbiol, 1984 Dec, 30(12), 1467 - 76
Oxygen toxicity in Treponema pallidum: deoxyribonucleic acid single-stranded breakage induced by low doses of hydrogen peroxide; Steiner BM et al.; The effect of hydrogen peroxide on Treponema pallidum was investigated . The in vitro loss of virulence (as measured by rabbit inoculation) of T . pallidum was accelerated by as low as 100 microM hydrogen peroxide in the complex maintenance medium used . Higher doses led to rapidly accelerated death with 500 microM hydrogen peroxide causing sterilization of the medium within 3 to 4 h . Since hydrogen peroxide is known to cause single-stranded breaks in DNA, the effect of hydrogen peroxide on the treponemal genome was examined . Extensive breakage was caused by 100 microM hydrogen peroxide as determined on alkaline sucrose gradients . A limit was reached at 250 microM and above . Single-stranded breaks could be demonstrated as early as 5-10 min after exposure to hydrogen peroxide when the treponemes were exposed to 250 microM hydrogen peroxide; accelerated death was evident by 2 h past exposure demonstrating that DNA breakage was preceding death . Treponemal death caused by penicillin did not result in DNA breakage . The repair-proficient bacterium Escherichia coli K-12 was compared with T . pallidum . It required 10-100 times more hydrogen peroxide to cause various levels of breakage . Escherichia coli K-12 rapidly repaired DNA breakage once hydrogen peroxide was removed by addition of catalase . Treponema pallidum, in comparison, showed little or no repair in vitro . Addition of catalase or dithiothreitol to the medium protected against all but a low level of breakage; this may reflect on the ability of catalase and reducing agents to protect T . pallidum against oxygen toxicity in vitro.

J Bacteriol, 1984 Dec, 160(3), 971 - 5
Isolation of a recombination-deficient mutant of Rhodopseudomonas capsulata; Genthner FJ et al.; To facilitate genetic analysis in the purple photosynthetic bacterium Rhodopseudomonas capsulata, a recombination-deficient derivative was sought . A UV irradiation-sensitive mutant (FG106F) was isolated after mutagenesis, and two procedures were used to determine the recombinational capacity of the mutant . First, recombinants were not detected after transduction of this derivative by the phage-like vector gene transfer agent . Second, an R-prime plasmid containing appropriately marked genes for photosynthesis was introduced by conjugation, and again no recombinants were observed . Additional phenotypes displayed by the mutant that are characteristic of a defect in recombination were an increased sensitivity to DNA-damaging antibiotics and a tendency to filament.

J Bacteriol, 1984 Dec, 160(3), 1137 - 45
Cloning of the major protein of the Caulobacter crescentus periodic surface layer: detection and characterization of the cloned peptide by protein expression assays; Smit J et al.; A precisely ordered crystalline array is found on the surface of the bacterium Caulobacter crescentus CB15 . Using an immunological assay, we identified recombinant bacteriophage clones expressing the predominant protein of this structure from a lambda 1059 library of C . crescentus CB15 DNA . A single 4.4-kilobase HindIII fragment encoded a polypeptide whose antigenic determinants, molecular weight, and peculiar solubilization properties were identical with those of the authentic predominant polypeptide (130K) of the surface array . The 130K protein was produced as a discrete product as a result of gene transcription initiated from a lambda promoter; several experiments suggested that the Caulobacter promoter for this gene is not efficiently recognized by the Escherichia coli transcription machinery . Genomic Southern analysis revealed a single copy of the 130K protein gene per genome . The 130K protein gene was hybridized with DNA of two closely related laboratory strains of C . crescentus which have lost their ability to produce a surface array . One of these strains, CB2, possesses an homologous copy of the 130K gene, whereas DNA from the other strain, CB13B1a, showed a lesser degree of hybridization to the 130K gene probe; genomic fragments which did hybridize were of different sizes in CB13 as compared with those of CB15 . These findings are discussed in relation to studies of the surface array function and its role in cellular morphogenesis in this stalk-forming bacterium.

Sci Total Environ, 1984 Nov, 39(3), 237 - 49
Incidence of Legionella organisms in selected Ontario (Canada) cities; Dutka BJ et al.; The distribution of Legionella pneumophila in water inside buildings was examined by means of culture methods . Cooling tower sumps and condenser valves harboured the organism at the highest frequency and in the highest concentrations . The bacterium was also frequently isolated from potable water systems, including hot and cold mixed taps, drinking water fountains and showers . When water quality parameters were examined, only elevated pH, total particulate nitrogen and alkalinity were correlated with the occurrence of L . pneumophila . Survival of the organism in water was increased at slightly basic pH and lower temperatures . The proliferation of the organism in water within buildings is probably due to a number of interrelated environmental factors that influence its survival and growth.

Arch Microbiol, 1984 Nov, 139(4), 319 - 25
Construction of a gene bank of Rhodopseudomonas capsulata using a broad host range DNA cloning system; Klug G et al.; A gene bank of the phototrophic bacterium Rhodopseudomonas capsulata was constructed using the binary plasmid system pRK290/pRK2013 . Fragments of about 20 kb of chromosomal DNA of R . capsulata strain 37b4 were inserted into the cloning vector pRK290 . The hybrid plasmids of the gene bank, maintained in Escherichia coli HB101 were transferred by conjugation to R . capsulata strains defective in the photosynthetic apparatus with frequencies of 5 X 10(-4) to 5 X 10(-2) . Phototrophically growing transconjugants occurred with frequencies of 5 X 10(-7) to 5 X 10(-6) . Recombination between the hybrid plasmids and the R . capsulata chromosome was shown . The hybrid plasmid pRCF1002, carrying a 25 kb insert of R . capsulata wild type DNA, was isolated from one E . coli clone of the gene bank . It reconstituted some bacteriochlorophyll- and photosynthetic negative mutants to phototrophic growth.

Chem Biol Interact, 1984 Nov, 52(1), 79 - 92
Irreversible binding of the chloropromazine radical cation and of photoactivated chlorpromazine to biological macromolecules; de Mol NJ et al.; The irreversible binding of chlorpromazine radical cation (CPZ+.) and photoactivated chlorpromazine (CPZ) to calf thymus DNA in vitro and bacterial macromolecules in intact bacterium cells was investigated . CPZ+ . may be formed in vivo metabolically and photochemically . CPZ+ . and photo-activated CPZ bind covalently to double- and single-strand DNA . The conformation of the DNA appeared to be important for the CPZ+ . reactivity: though CPZ+ . is less stabilized by complex formation with single-strand DNA, the reaction rate and the binding capacity of DNA-complexed CPZ+ . with single-strand DNA is larger than with double-strand DNA . Photoactivated CPZ binds considerably to proteins, DNA and RNA in the intact bacterium cells . In spite of the relatively short lifetime of CPZ+ . in the presence of the cells CPZ+ . also binds irreversibly to bacterial DNA, RNA and proteins . The consequences of covalent binding for the cytotoxicity and genotoxicity of CPZ+ . and photoactivated CPZ and the possible role for CPZ+ . as an intermediate in the photobinding of CPZ is discussed.

Genetika, 1984 Nov, 20(11), 1783 - 91
{Inheritance of hybrid plasmid pAS*-21 by cells of the purple phototropic nitrogen-fixing bacterium Rhodopseudomonas sphaeroides}; Dubeikovskii AN et al.; Clones of purple nitrogenfixing prototrophic bacterium Rhodopseudomonas sphaeroides carrying an incertion into the chromosome of the hybrid pAS8-121 (RP4-ColE1 (repA::Tn7} plasmid were analysed . It is revealed that plasmid integration could be due to both Tn7 and other migrating elements (IS8 and possibly, to resident migrating elements of purple bacteria) . The plasmid pAS 8-121 can be autonomously transferred from the cointegrate state into Escherichia coli K-12; the plasmid is not inherited autonomously in cells of the purple bacterium . In E . coli cells R' derivatives of the plasmid carrying R . sphaeroides chromosomal fragments may be formed . The R' plasmids with fragments of plasmid DNA substituted for chromosomal material of R . sphaeroides were selected in E . coli K-12 cells among deleted (Kms) derivatives of pAS8-121.

J Mol Biol, 1984 Oct 25, 179(2), 185 - 214
Rhodopseudomonas blastica atp operon . Nucleotide sequence and transcription; Tybulewicz VL et al.; The nucleotide sequence has been determined of a 12,368 base-pair region of DNA cloned from the non-sulphur photosynthetic bacterium Rhodopseudomonas blastica . It contains a cluster of six genes of which five encode the subunits of F1-ATPase; the sixth codes for an unknown protein . The genes are arranged in the same order as in the Escherichia coli unc operon, except that the unknown gene is placed between those for gamma and beta subunits . Neither the genes for F0 subunits, nor a homologue of the E . coli uncI gene is associated with this locus . The six genes are transcribed from a single promoter and we have designated this region the R . blastica atp operon . The two distal genes, beta and epsilon, may also be transcribed from a second promoter . Initiation and termination points for transcription have been identified by primer extensions and S1 nuclease mapping experiments . Signals involved in initiation of translation (Shine and Dalgarno sequences) and termination of transcription in the photosynthetic bacterium resemble those in E . coli . However, no common features can be identified in these two bacteria between 5' regions adjacent to sites of initiation of transcription . The sequence also contains a gene that encodes a protein homologous to discoidin, a cell surface lectin of Dictyostelium discoideum thought to be involved in cell--cell aggregation . Seven other reading frames have not been identified.

Biochim Biophys Acta, 1984 Oct 17, 777(1), 41 - 55
Cell-cycle-specific biosynthesis of the photosynthetic membrane of Rhodopseudomonas sphaeroides . Structural implications; Yen GS et al.; Structural changes association with the intracytoplasmic membrane during the cell cycle of the photosynthetic bacterium Rhodopseudomonas sphaeroides have been studied by freeze-fracture electron microscopy . The isolated intracytoplasmic membrane vesicles, chromatophores, were fused in order to obtain large fracture faces, allowing more precise measurements and statistical analysis of both intramembrane particle density and size determinations . The intramembrane particle density of the protoplasmic face (PF) of the intracytoplasmic membrane, (from 4970 to 8290/micrometers 2), was shown to be a linear function of the protein/phospholipid ratio (from 2.5 to 5.1, w/w) of the intracytoplasmic membrane . Under constant light intensity, both the average particle size and particle size distribution remained unchanged during the cell cycle . These results provide the structural basis for the earlier reported cell-cycle-specific variations in both protein/phospholipid ratio and alternation in phospholipid structure of the intracytoplasmic membrane of R . sphaeroides during photosynthetic growth . The average particle diameter in the PF face of the intracytoplasmic membrane was 8.25, 9.08 and 9.75 nm at incident light intensities of 4000, 500 and 30 ft X cd, respectively . When chromatophores were fused with small, unilamellar liposomes, the intramembrane particle density decreased as input liposome phospholipid increased, whereas the particle size remained constant and particle distribution became random.

J Mol Biol, 1984 Oct 15, 179(1), 151 - 5
Crystallization and preliminary x-ray diffraction study of the 3-Fe ferredoxin II from the bacterium Desulfovibrio gigas; Sieker LC et al.; The 3-Fe ferredoxin (FdII) from the bacterium Desulfovibrio gigas has been crystallized at pH 5.0 and 23 degrees C in two different crystal forms . One form is monoclinic, space group C2, with unit cell parameters a = 40.78 A, b = 44.98 A, c = 26.47 A, beta = 104.6 degrees, and one monomer of the FdII tetramer per asymmetric unit . The molecule can be either the monomer of molecular weight 6400 or a dimer of twice this molecular weight with 2-fold symmetry coincident with the 2-fold axis of the crystal . The other crystal form is orthorhombic, space group P2(1)2(1)2 and unit cell parameters a = 109.5 A, b = 37.0 A, c = 30.5 A . The asymmetric unit of this crystal contains two monomers of FdII . The orthorhombic crystal has not been reproduced since the initial crystallization.

Gan To Kagaku Ryoho, 1984 Oct, 11(10), 2227 - 35
{Preparation of repeatedly and effectively usable L-asparaginase by a chemical modification}; Nishimura H et al.; The anti-tumor activity of L-asparaginase (EC . 3.5.1.1.) has been conclusively demonstrated . Its therapeutic application, however, has been hampered by its short clearance time in the circulation and high immunogenicity . In order to solve these problems, polyethylene glycol, a linear synthetic and non-immunogenic polymer, was introduced covalently into the amino groups in the enzyme molecule . Monomethoxypolyethylene glycol with molecular weight of 5000 was activated with cyanuric chloride to obtain activated PEGs {2, 4-bis (O-methoxypolyethyleneglycol)-6-chloro-s-triazine} . L-Asparaginase lost its immunoreactivity against its antibodies after the modification of 52 out of 92 amino groups in the molecule . This modified asparaginase retained 11% of its enzymic activity under the physiological condition . When the modified asparaginase was administered in rodents, it diminished the serum asparagine level and its enzymic activity persisted in the circulation 10 to 20 times longer than that of native enzyme . Furthermore, repeated injections of modified asparaginase did not induce any significant anti-asparaginase antibody production . Modified asparaginase showed a superior anti-tumor activity to the native counterpart irrespective of the presence of anti-asparaginase antibodies, when it was tested with murine Gardner lymphoma . This chemical modification should make it possible for the first time to repeatedly and effectively use L-asparaginase obtained from a bacterium.

Environ Res, 1984 Oct, 35(1), 228 - 36
Growth rate of the bacterium Sphaerotilus natans in lead-containing medium and the effect of calcium ions; Medon P et al.; Growth rate of bacteria Sphaerotilus natans in lead-containing medium (1 X 10(-4) M Pb2+) and bioaccumulation of lead in the bacterial cells were investigated together with the effect of calcium ions on these processes . A rapid increase in biomass was observed in the presence of calcium and lead whereas calcium alone had no visible effect on the bacterial growth . The increase in biomass in the presence of lead and calcium was accompanied by a pronounced drop in lead content in the bacterial cells . This suggests that calcium ions protect the bacterial cells against lead poisoning.

J Submicrosc Cytol, 1984 Oct, 16(4), 619 - 23
Photosynthetic reaction centers in artificial membranes: estimating protein dimensions by freeze-fracture and freeze-etching; Miller KR et al.; Because estimates of size and shape for membrane proteins are difficult to obtain directly, many workers have incorporated purified proteins into artificial lipid bilayers . Freeze-fracturing has then been used to provide a measure of the approximate size and shape of the membrane protein . We have formed reconstituted membranes containing the photosynthetic reaction center of Rhodopseudomonas viridis, a photosynthetic bacterium . The size and shape of this reaction center is accurately known from studies of negatively stained crystals of the protein to be approximately 4.5 X 6.0 nm . Freeze-fracture images of the reaction center in phosphatidyl choline liposomes show particles formed after reconstitution with an average diameter of 12.3 nm, much larger than the actual size of the protein . Deep-etched images of the surfaces of the liposomes, in which each individual reaction center complex can be seen clearly, show why the diameter of the protein is exaggerated in freeze-fracture . The individual reaction centers tend to cluster into large groups, allowing several individual reaction centers to be visualized as a single (much larger) particle in freeze-fracture . Freeze-fracturing, although a valuable tool in the analysis of membrane structure in natural and artificial membranes, must be used with caution in the estimation of molecular sizes and shapes.

J Appl Bacteriol, 1984 Oct, 57(2), 279 - 90
A general-purpose system for characterizing medically important bacteria to genus level; Feltham RK et al.; A computer program and accompanying data matrix have been prepared for bacteria of medical interest, to assist the assignment of an unidentified bacterium to the most likely genus . The results on a set of relatively simple tests are entered . The program prints the more likely genera, followed by a list of diagnostic tables in Cowan & Steel (1974) and Buchanan & Gibbons (1974) . Where available, identification matrices for further computer-assisted study, are presented . This program may be of particular help in laboratories where a wide range of bacteria have to be identified.

Arch Biochem Biophys, 1984 Oct, 234(1), 73 - 81
Comparison of the properties of two hydrogenases from the photosynthetic bacterium Chromatium vinosum; Serra JL et al.; Chromatium vinosum hydrogenases I and II were purified to specific activities of 9.6 and 28.0 units/mg protein, respectively . They have the same isoelectric point (pI = 4.1), and their visible spectra are typical of iron-sulfur proteins . Hydrogenase II in general was more stable than hydrogenase I . Both enzymes lost their activities slowly during storage in air, and this inactivation was more apparent in preparations of hydrogenase I . Bovine serum albumin helped to stabilize hydrogenase I against thermal and storage inactivation . The pH optima of H2-evolution activity of hydrogenases I and II were 7.4 and 5.4, respectively . Neither enzyme was able to evolve H2 from reduced ferredoxins as the sole electron carrier, but ferredoxins had an effect on the activity with methyl viologen as carrier to hydrogenase I . None of the natural compounds tested was able to serve as a physiological donor for H2 production . Hydrogenase I was more susceptible than hydrogenase II to inhibition by heavy metal ions and other enzyme inhibitors . Both enzymes were reversibly inhibited by CO with Ki values of 12 and 6 Torr for hydrogenase I and II, respectively . Hydrogenase I was more sensitive to denaturation by urea and guanidinium chloride while hydrogenase II was more susceptible to sodium dodecyl sulfate . Both enzymes were rapidly and irreversibly inactivated by dimethyl sulfoxide . Hydrogenase I evolved H2 from methyl viologen and ferredoxin photoreduced by chloroplasts . The enzymes differed in their iron and acid-labile sulfur contents.

Biochem Biophys Res Commun, 1984 Sep 28, 123(3), 1234 - 9
Purification and properties of cytochrome b from photosynthetic bacterium Rhodopseudomonas sphaeroides R-26; Yu L et al.; Cytochrome b of R . sphaeroides R-26 has been purified from the isolated cytochrome b-c1 complex to homogeneity . The purification procedure involves Triton X-100 and urea solubilization, calcium phosphate column chromatography at different pH values, and ammonium sulfate fractionation . The purified protein contains 23 nmol heme per mg protein and has an apparent molecular weight of 43,000, as determined by sodium dodecylsulfate polyacrylamide gel electrophoresis . The spectral characteristics of purified cytochrome b are similar to those of cytochrome b in the active cytochrome b-c1 complex but with a lower absorbance . The amino acid composition has been determined and compared with cytochrome b purified from other sources.

J Biochem (Tokyo), 1984 Sep, 96(3), 691 - 9
Proton correlation NMR studies of metabolism in Rhodopseudomonas palustris; Imai Y et al.; A 1H correlation NMR study is reported, on the metabolism of a photosynthetic bacterium, Rhodopseudomonas palustris, in dark and light anaerobic conditions . Alkali treatment as well as sonication of the cells were employed to follow the process of accumulation and decomposition of poly-beta-hydroxybutyrate (PHB) which is the reserve material for the bacterium . It was shown that synthesis of PHB from trans-crotonate proceeds in the granules of the cells . It was also demonstrated that under anaerobic light conditions photometabolism and glycolysis generally compete with concomitant synthesis and decomposition of PHB, respectively, and that glycolysis gradually replaces photometabolism with aging of the cells . In contrast, glycolysis is always predominant in the dark and PHB is primarily used as the carbon source . It was observed that photo-induced transport of beta-hydroxybutyrate through the membrane occurs when photometabolism and glycolysis are equally active in the light . The implications of this observation are briefly discussed.

Isr J Med Sci, 1984 Sep, 20(9), 836 - 9
Spiroplasmas and the transfer of genetic material by transformation and transfection; Bove JM et al.; Two plasmids, pMH1 with 7 kbp and pM41 with 8 kbp were purified from Spiroplasma citri strains MH and M4 respectively . On the basis of guanine + cytosine content and restriction enzyme mapping, the two plasmids are different . The linearized pMH1 plasmid was introduced into Escherichia coli plasmid vector pBR328 and could be cloned in E . coli . Using radioactive probes specific for each plasmid, we found that pM41 was present in three additional S . citri strains and in three other spiroplasmas not belonging to the S . citri species . pMH1 was found as a free 7-kbp plasmid only in the S . citri strain MH . However, the pMH1 probe hybridized strongly with high molecular weight DNA of several S . citri strains and strains of spiroplasmas other than S . citri . The major membrane protein of S . citri, spiralin, is strongly antigenic and rabbit antibodies against whole S . citri cells strongly react with spiralin . Thus, the enzyme-linked immunosorbent assay (ELISA) has been used to screen E . coli clones that were transformed with HindIII-generated S . citri DNA fragments inserted into the HindIII site of pBR328 . One E . coli transformant strongly reacted in ELISA with S . citri polyclonal antiserum . The same transformant also gave a positive reaction with monospecific antiserum against spiralin . These results demonstrate that a gene from S . citri, the spiralin gene, could be expressed in a bacterium . The isometric virus SV4, infecting honeybee spiroplasmas of Group I-2, was shown to possess circular single-stranded DNA of molecular weight 1.7 X 10(6) Da . Transfection of spiroplasma G1 with purified DNA of SV4 was achieved . These experiments open the way to the introduction of foreign genes into spiroplasmas.

J Biochem (Tokyo), 1984 Sep, 96(3), 585 - 92
Ferredoxins from the photosynthetic purple non-sulfur bacterium Rhodopseudomonas palustris . Isolation and amino acid sequence of ferredoxin I; Minami Y et al.; Two ferredoxins, ferredoxins I and II, were prepared from Rhodopseudomonas palustris . They were separated on a Sephadex column after carboxymethylation and ferredoxin I, the major component, was subjected to an amino acid sequence study . The protein was composed of 63 amino acid residues and the sequence was as follows: (sequence; see text) . The molecular weight was calculated to be 6,718, excluding iron and sulfur atoms . The distribution of the nine cysteine residues was similar to but clearly distinct from those of ferredoxins of other photosynthetic bacteria . Comparison of this ferredoxin with those of other bacteria suggests that the photosynthetic bacteria evolved on separate lines . Ferredoxin II was also subjected to analyses of amino acid composition and terminal sequences, but no further study was possible due to the limited material . Although the composition was different from that of ferredoxin I, the terminal sequences were exactly the same as those of ferredoxin I.

Pediatr Infect Dis, 1984 Sep-Oct, 3(5), 467 - 86
The concept of pertussis as a toxin-mediated disease; Pittman M; Pertussis (whooping cough), a two-stage process of disease (respiratory colonization and toxin-mediated disease) is caused by B . pertussis . The bacterium is unique . It is a pathogenic parasite with habitat only in human beings . Growth in the pathogenic form, both in in vitro and in vivo, requires conditions that permit the expression of pertussis toxin (PT) (also known as histamine-sensitizing factor, lymphocyte-leukocyte-promoting factor, islet-activating factor and pertussigen) . The expression of growth and PT appear to be genetically interrelated . For multiplication in vitro the medium must be free of substances, such as fatty acids, that inhibit the enzymatic action required for elaboration of PT . In vivo the bacteria are uniquely localized to the cilia of the respiratory epithelium where they multiply . In situ the bacteria inhibit natural defenses of the respiratory tract (cilial, phagocytic and other activities); they tend not to spread and do not invade the underlying tissue . The extent of the areas of colonization, directly related to the number of bacteria in the infecting inoculum, influences the amount of toxin elaborated and consequently the intensity of the clinical symptoms . Other factors that influence the clinical disease are the inordinate susceptibility of the infant and genetically controlled susceptibility . A specific role for PT in the initial establishment of the infection is not clear, but it seems definite that PT-specific immunity influences the clearance of colonization in about 4 to 5 weeks . The clinical symptoms become manifest when the bacteria are waning . This clearance is influenced by the synthesis of IgA antibodies and pertussis toxin antibodies that may act by inhibiting the "enzyme" required for growth or by another mechanism . The pathology of the disease is the result of altered cellular functions of toxin-sensitized cells, not by histologic damage . PT is composed of two functional components like other exotoxins that cause infectious disease (e.g . diphtheria, cholera) . Certain sites on one component enable PT to bind to specific receptors on tissue cells and enter the cell . The toxin ADP ribosylates a regulatory protein of the cytoplasmic membrane and thereby alters the function of the cell . Affected (sensitized) cells are insulin-secretory islets of the pancreas, lymphocytes and leukocytes, heart cells and others that have not been clearly identified, e.g . those that effect paroxysms and neurologic disturbances . The altered function of the cell in vitro is irreversible, and the restoration of the function of a particular tissue in vivo appears to be dependent on the renewal of the cells.(ABSTRACT TRUNCATED AT 400 WORDS)

Proc Natl Acad Sci U S A, 1984 Sep, 81(18), 5816 - 20
Construction of Tn5 lac, a transposon that fuses lacZ expression to exogenous promoters, and its introduction into Myxococcus xanthus; Kroos L et al.; A promoterless trp-lac fusion fragment was inserted near one end of the bacterial transposon Tn5 in the correct orientation to fuse lacZ gene expression to promoters outside Tn5 . The resulting transposon, Tn5 lac, retains the kanamycin-resistance gene of Tn5 and transposes in Escherichia coli at 6% the frequency of Tn5 to many different sites in a bacteriophage lambda target . Expression of beta-galactosidase, the product of the lacZ gene, from Tn5 lac insertions in phage lambda depends both on insertion into a transcription unit in the correct orientation and on the regulation of the promoter of the transcription unit, verifying that by transposition Tn5 lac can fuse lacZ expression to outside promoters . An insertion of Tn5 lac in bacteriophage P1 was isolated and used to introduce Tn5 lac into Myxococcus xanthus, a bacterium that undergoes multicellular development . Stable kanamycin-resistant transductants are obtained that contain no P1 DNA sequences but have Tn5 lac inserted at different sites in the Myxococcus chromosome . Individual transductants express different levels of beta-galactosidase . A chromogenic substrate of beta-galactosidase, 5-bromo-4-chloro-3-indolyl beta-D-galactoside, is toxic in Myxococcus when cleaved in large amounts . In principle, Tn5 lac could be used to assay transcription in any bacterium in which Tn5 can transpose and beta-galactosidase can be measured.

J Bacteriol, 1984 Aug, 159(2), 776 - 9
Changes in cell surface hydrophobicity of Myxococcus xanthus are correlated with sporulation-related events in the developmental program; Kupfer D et al.; Cell surface hydrophobicity was measured in the bacterium Myxococcus xanthus during vegetative growth, fruiting body formation, and glycerol-induced spore formation by the method of Rosenberg et al . (FEMS Microbiol . Lett . 9:29-33, 1980) . A significant decrease in cell surface hydrophobicity was observed 12 to 36 h after fruiting body formation and 60 to 120 min after glycerol-induced sporulation . The hydrophilic shift was correlated with the ability of the cells to sporulate but not with their ability to aggregate . Sucrose gradient purification removed the hydrophilic substance from the fruiting body spores but not from the glycerol-induced spores . The change in cell surface hydrophobicity in M . xanthus should be a useful developmental marker.

Hastings Cent Rep . 1984 Aug;14(4):17.
A cotton dust study unmasked; Levine C; KIE: The Dan River Company, citing news reports damaging to its image, has abandoned a proposed study to test a theory that byssinosis (brown lung disease) is caused by a bacterium growing in cotton rather than by inhalation of cotton dust . With state approval to exceed federal standards on cotton dust exposure, the company submitted the study to the Occupational Safety and Health Administration as a "variance," not as human subjects research . Levine contends that the proposal violated all major criteria of the federal regulations for protection of research subjects--scientific objectivity, balanced risks and benefits, and voluntary and informed consent .

J Bacteriol, 1984 Aug, 159(2), 693 - 9
Carbon monoxide dehydrogenase from Rhodospirillum rubrum; Bonam D et al.; The carbon monoxide dehydrogenase from the photosynthetic bacterium Rhodospirillum rubrum was purified over 600-fold by DEAE-cellulose chromatography, heat treatment, hydroxylapatite chromatography, and preparative scale gel electrophoresis . In vitro, this enzyme catalyzed a two-electron oxidation of CO to form CO2 as the product . The reaction was dependent on the addition of an electron acceptor . The enzyme was oxygen labile, heat stable, and resistant to tryptic and chymotryptic digestion . Optimum in vitro activity occurred at pH 10.0 . A sensitive, hemoglobin-based assay for measuring dissolved CO levels is presented . The in vitro Km for CO was determined to be 110 microM . CO, through an unknown mechanism, stimulated hydrogen evolution in whole cells, suggesting the presence of a reversible hydrogenase in R . rubrum which is CO insensitive in vivo.

Eur J Biochem, 1984 Jul 2, 142(1), 21 - 8
Purification, characterization and redox properties of hydrogenase from Methanosarcina barkeri (DSM 800); Fauque G et al.; A soluble hydrogenase from the methanogenic bacterium, Methanosarcina barkeri (DSM 800) has been purified to apparent electrophoretic homogeneity, with an overall 550-fold purification, a 45% yield and a final specific activity of 270 mumol H2 evolved min-1 (mg protein)-1 . The hydrogenase has a high molecular mass of approximately equal to 800 kDa and subunits with molecular masses of approximately equal to 60 kDa . The enzyme is stable to heating at 65 degrees C and to exposure to air at 4 degrees C in the oxidized state for periods up to a week . The overall stability of this enzyme is compared with other hydrogenase isolated from strict anaerobic sulfate-reducing bacteria . Ms . barkeri hydrogenase shows an absorption spectrum typical of a non-heme iron protein with maxima at 275 nm, 380 nm and 405 nm . A flavin component, identified as FMN or riboflavin was extracted under acidic conditions and quantified to approximately one flavin molecule per subunit . In addition to this component, 8-10 iron atoms and 0.6-0.8 nickel atom were also detected per subunit . The electron paramagnetic resonance (EPR) spectrum of the native enzyme shows a rhombic signal with g values at 2.24, 2.20 and approximately equal to 2.0 . probably due to nickel which is optimally measured at 40 K but still detectable at 77 K . In the reduced state, using dithionite or molecular hydrogen as reductants, at least two types of g = 1.94 EPR signals, due to iron-sulfur centers, could be detected and differentiated on the basis of power and temperature dependence . Center I has g values at 2.04, 1.90 and 1.86, while center II has g values at 2.08, 1.93 and 1.85 . When the hydrogenase is reduced by hydrogen or dithionite the rhombic EPR species disappears and is replaced by other EPR-active species with g values at 2.33, 2.23, 2.12, 2.09, 2.04 and 2.00 . These complex signals may represent different nickel species and are only observable at temperatures higher than 20 K . In the native preparation, at high temperatures (T greater than 35 K) or in partially reduced samples, a free radical due to the flavin moiety is observed . The EPR spectrum of reduced hydrogenase in 80% Me2SO presents an axial type of spectrum only detectable below 30 K.

Biophys J, 1984 Jul, 46(1), 57 - 64
Magnetosome dynamics in magnetotactic bacteria; Ofer S et al.; Diffusive motions of the magnetosomes (enveloped Fe3O4 particles) in the magnetotactic bacterium Aquaspirillum magnetotacticum result in a very broad-line Mossbauer spectrum (T approximately 100 mm/s) above freezing temperatures . The line width increases with increasing temperature . The data are analyzed using a bounded diffusion model to yield the rotational and translational motions of the magnetosomes as well as the effective viscosity of the material surrounding the magnetosomes . The results are {theta 2} l/2 less than 1.5 degrees and {x2} 1/2 less than 8.4 A for the rotational and translational motions, respectively, implying that the particles are fixed in whole cells . The effective viscosity is 10 cP at 295 K and increases with decreasing temperature . Additional Fe3+ material in the cell is shown to be associated with the magnetosomes . Fe2+ material in the cell appears to be associated with the cell envelope.

J Bacteriol, 1984 Jul, 159(1), 26 - 35
Isolation and characterization of nonspreading mutants of the gliding bacterium Cytophaga johnsonae; Chang LE et al.; Three approaches were taken to isolate a total of 153 nonspreading mutants derived from our laboratory strain of Cytophaga johnsonae, UW101, or from its auxotrophic derivative, UW10538 . Characterization of 109 of these mutants led to their placement in five general categories: (i) motile, nonspreading (MNS) mutants whose cells are motile to various degrees but whose colonies fail to spread on agar gels under any conditions of incubation; (ii) conditional nonspreading (CNS) mutants with motile cells whose colonies require more moisture to spread on agar gels than do those of wild-type cells; (iii) filamentous conditional motility (FCM) mutants whose cells grow as nonmotile filaments or as motile cells with wild-type morphology, depending on conditions of incubation; (iv) short, tumbling, nonspreading (STN) mutants with short cells that tumble constantly; and (v) truly nonmotile (TNM) mutants whose cells never move and whose colonies never spread under any conditions tested . All TNM mutants exhibited a remarkable pleiotropy not seen in the other four classes of mutants: all were resistant to 39 phages to which wild-type cells are sensitive, and all were unable to digest chitin, which is digested by wild-type cells . The correlation between ability to move and phage sensitivity was strengthened further by showing that 150 additional TNM mutants derived from UW101 and 43 TNM mutants derived from 29 independent isolates of C . johnsonae were resistant to all phages to which their parents were sensitive . Furthermore, motile revertants of TNM mutants became phage sensitive, and temperature-sensitive mutants were motile and phage sensitive at 25 degrees C and nonmotile and phage resistant at 32 degrees C . Evidence supports the conclusion that any mutation rendering cells truly nonmotile invariably alters cell surface-associated properties such as phage sensitivity and chitin digestion merely as a consequence of changing a moving cell surface to a static surface.

J Bacteriol, 1984 Jul, 159(1), 222 - 7
Isolation of pigmentation mutants of the green filamentous photosynthetic bacterium Chloroflexus aurantiacus; Pierson BK et al.; Mutants deficient in the production of bacteriochlorophyll c (Bchl c) and one mutant lacking colored carotenoids were isolated from the filamentous gliding bacterium Chloroflexus aurantiacus . Mutagenesis was achieved by using UV radiation or N-methyl-N'-nitro-N-nitrosoguanidine . Several clones were isolated that were deficient in Bchl c synthesis . All reverted . One double mutant deficient both in Bchl c synthesis and in the synthesis of colored carotenoids under anaerobic conditions was isolated . Isolation of a revertant in Bchl c synthesis from this double mutant produced a mutant strain of Chloroflexus that grew photosynthetically under anaerobic conditions and lacked colored carotenoids . Analysis of pigment contents and growth rates of the mutants revealed a positive association between growth rate and content of Bchl c under light-limiting conditions.

Microbiologica, 1984 Jul, 7(3), 263 - 6
A bald superfertile U.V.-resistant strain in Streptomyces coelicolor A3(2); Puglia AM et al.; The 'bald'(bld) mutants of filamentous bacterium Streptomyces coelicolor A3(2) are characterized by a lack of aerial myceliumand spores . A 'bald' mutant was isolated exhibiting unusual features . It forms slightly sculptured colonies producing a red-orange mycelial pigment, large amounts of agarase and methylenomycin A; it is also highly resistant to U.V . killing . The bld mutation (bld F1) never reverted to bld+ phenotype and was localized very closed to met A.

Rev Infect Dis, 1984 Jul-Aug, 6(4), 579 - 86
Classics in infectious diseases . Toxic products of Bacterium enteritidis and of related micro-organisms . By Sara Elizabeth Branham . Journal of Infectious Diseases 1925; Biosynthesis of the sulfonolipid 2-amino-3-hydroxy-15-methylhexadecane-1-sulfonic acid in the gliding bacterium Cytophaga johnsonae; The biosynthesis of the sulfonolipid 2-amino-3-hydroxy-15-methylhexadecane-1-sulfonic acid (capnine) was studied by measuring the incorporation of possible precursors into the lipid by cells grown in the presence of precursors which were labeled with stable isotopes . Cells grown on yeast extract in the presence of DL-{3,3-2H2}serine contained 40.1 mol% of the protein-bound serine and 5.0 mol% of the protein-bound cysteine derived from the labeled serine . Cells grown in the presence of DL-{3,3-2H2}cystine acid contained 86.4 mol% of the molecules that had two deuteriums . These results are consistent with the possibility that biosynthesis of capnine occurs by the condensation of 13-methylmyristoyl-coenzyme A with cysteic acid, in a reaction analogous to the condensation of a palmitoyl-coenzyme A with serine to form 3-keto-sphinganine during the biosynthesis of sphingolipids.

Infect Immun, 1984 Jul, 45(1), 101 - 6
Antigen from Francisella tularensis: nonidentity between determinants participating in cell-mediated and humoral reactions; Sandstrom G et al.; After tularemia vaccinations, most individuals respond with cell-mediated and humoral immunity as disclosed by the lymphocyte stimulation test and enzyme-linked immunosorbent assay (ELISA), respectively . There is, however, no correlation between the magnitudes of the two responses, and some individuals show one of the responses only . We now report that the two responses are directed towards different antigenic determinants of the bacterium . Ether-water extraction of the live vaccine strain of Francisella tularensis gave a high yield of material reacting in ELISA as well as in the lymphocyte stimulation test . However, the specificity of the extract was low insofar as it reacted not only with lymphocytes and antibodies of tularemia-vaccinated individuals but also to a fairly high extent with those of nonvaccinated individuals . By using the extract as a starting material, a preparatory procedure was developed, resulting in antigen of high specificity in the two tests . The antigen prepared was a high-molecular-weight, carbohydrate-protein complex . Proteinase K treatment of the antigen abolished the lymphocyte-stimulating activity but did not decrease ELISA activity at all . Periodate treatment, on the other hand, greatly reduced ELISA activity but did not decrease the lymphocyte-stimulating activity . Thus, determinants of F . tularensis responsible for immunospecific lymphocyte stimulation seem to reside in protein, whereas ELISA activity seems to be due mostly to carbohydrate determinants.

Biochem Biophys Res Commun, 1984 Jun 29, 121(3), 755 - 61
Inhibition of photosynthetic sulfide oxidation by organic cations; Brune DC et al.; Photosynthetic sulfide oxidation by the purple sulfur bacterium Chromatium vinosum is strongly inhibited by the organic cations benzyl viologen ( BV2 +) and tetraphenylphosphonium (TPP+) at micromolar concentrations . Both are much more inhibitory at pH 8 than at pH 7 . Inhibition probably results from uptake of benzyl viologen and tetraphenylphosphonium in response to an electrical potential gradient across the plasma membrane which increases in magnitude with increasing pH . Although both compounds appear to have the same mode of action, the biochemical mechanism of their inhibition remains to be determined.

J Theor Biol, 1984 Jun 7, 108(3), 405 - 11
Coevolution of directly contacting proteins in phage-bacterium ecosystem: possibility or fiction?
Ratner VA, Rodin SN.
The possibility of phage and bacterium coevolution at the level of directly contacting proteins is considered . The arguments are presented that a deterministic approach is quite legitimate in theoretical descriptions of the main features of the process.

J Mol Biol, 1984 Jun 5, 175(4), 469 - 92
Gene expression during development of Myxococcus xanthus . Analysis of the genes for protein S; Downard JS et al.; Protein S is an abundant spore coat protein produced during fruiting body formation (development) of the bacterium Myxococcus xanthus . We have cloned the DNA which codes for protein S and have found that this DNA hybridizes to three protein S RNA species from developmental cells but does not hybridize to RNA from vegetative cells . The half-life of protein S RNA was found to be unusually long, about 38 minutes, which, at least in part, accounts for the high level of protein S synthesis observed during development . Hybridization of restriction fragments from cloned M . xanthus DNA to the developmental RNAs enabled us to show that M . xanthus has two directly repeated genes for protein S (gene 1 and gene 2) which are separated by about 10(3) base-pairs on the bacterial chromosome . To study the expression of the protein S genes in M . xanthus, eight M . xanthus strains were isolated with Tn5 insertions at various positions in the DNA which codes for protein S . The strains which contained insertions in gene 1 or between gene 1 and gene 2 synthesized all three protein S RNA species and exhibited normal levels of protein S on spores . In contrast, M . xanthus strains exhibited normal levels of protein S on spores . In contrast, M . xanthus strains with insertions in gene 2 had no detectable protein S on spores and lacked protein S RNA . Thus, gene 2 is responsible for most if not all of the production of protein S during M . xanthus development . M . xanthus strains containing insertions in gene 1, gene 2 or both genes, were found to aggregate and sporulate normally even though strains bearing insertions in gene 2 contained no detectable protein S . We examined the expression of gene 1 in more detail by constructing a fusion between the lacZ gene of Escherichia coli and the N-terminal portion of protein S gene 1 of M . xanthus . The expression of beta-galactosidase activity in an M . xanthus strain containing the gene fusion was shown to be under developmental control . This result suggests that gene 1 is also expressed during development although apparently at a much lower level than gene 2.

J Appl Bacteriol, 1984 Jun, 56(3), 457 - 63
A new rapid and sensitive bioluminescence assay for antibiotics that inhibit protein synthesis; Naveh A et al.; A new sensitive, rapid and simple bioluminescence assay for antibiotics inhibiting protein synthesis is described . In this assay the ability of the tested antibiotic to inhibit the de novo synthesis of the enzymes participating in the bacterial luminescence system is determined by means of a dark variant of a luminous bacterium that undergoes prompt induction of the luminescence system with certain DNA-intercalating agents . Upon induction, the in vivo luminescence of the dark variant is increased more than 50-fold within 30 min . Antibiotics that block the de novo synthesis of protein limit the development of luminescence at a level that was found to be a function of the antibiotic concentration . The minimum detectable concentration of antibiotics in the bioluminescence test, after 45-60 min of incubation, was 0.1 microgram/ml for streptomycin, gentamicin, kanamycin, lincomycin and chloramphenicol and 0.3 microgram/ml for neomycin, clindamycin and spectinomycin . The new bioluminescence test has been used to assay these antibiotics in serum.

Appl Environ Microbiol, 1984 Jun, 47(6), 1307 - 10
Effectiveness of 1-bromo-3-chloro-5,5-dimethylhydantoin against Legionella pneumophila in a cooling tower; Fliermans CB et al.; Cooling towers are considered to be man-made amplifiers of Legionella spp . Thus, the proper maintenance and choice of biocides is important . The only biocidal measure that has thus far been shown to be effective in field tests is the judicious use of chlorination . Perturbation studies with 1-bromo-3-chloro-5, 5-dimethylhydantoin (Bromicide; Great Lakes Chemical Corp., West Lafayette, Ind.) (BCD) were conducted on an industrial cooling tower shown to contain Legionella pneumophila . At the concentrations recommended by the manufacturer, neither the density nor the activity of L . pneumophila was affected . At comcentrations greater than 2.0 ppm (2.0 micorgram/ml) free of residual, BCD was not effective in reducing L . pneumophila to source water concentrations, nor was it effective in reducing the 2-p-iodophenyl-3-p-nitrophenyl-5-phenyl tetrazolium chloride activity of the bacterium in situ . The data indicate that at concentrations up to 2.0 ppm, BCD is not effective in these tower studies.

Biochimie, 1984 Jun, 66(6), 471 - 6
Quantification of SSB protein in E . coli and its variation during RECA protein induction; Villani G et al.; Using a two-site immunometric assay (IRMA) we quantified the concentration of single-stranded DNA binding protein (SSB) in several E . coli strains . We found approximately 7,000 monomers of SSB present per bacterium, and this number remained constant throughout the exponential phase of growth . Two ssb- mutants (ssb-1 and ssb-113) are defective in the induction of the S.O.S . pathway . One of the first functions expressed upon induction of the S.O.S . pathway is the amplification of recA protein (RECA), which we monitored by an IRMA assay similar to the one used for SSB quantification . By combining the two assays we determined the level of SSB and RECA in ssb- mutants or in SSB and RECA overproducer strains . We found: a) a normal induction of RECA following UV irradiation of E . coli bacteria overproducing SSB, b) a normal level of SSB in wild type and ssb-1 and ssb-113 mutants either in the absence or in the presence of S.O.S . inducing agents . We confirmed a severe impairment in the induction of RECA in these two mutants after nalidixic acid treatment . Our results suggest that the concentrations of RECA and SSB protein in E . coli are regulated by independent biochemical pathways.

J Bacteriol, 1984 Jun, 158(3), 1094 - 103
Plasmid rearrangements in the photosynthetic bacterium Rhodopseudomonas sphaeroides; Nano FE et al.; Mu d1(Ap lac) was introduced into the photosynthetic bacterium Rhodopseudomonas sphaeroides 2.4.1 . via the R-plasmid R751 in an attempt to isolate fusion derivatives involving photosynthetic operons . The selection system is potentially very powerful since R . sphaeroides is normally Lac negative . Among the exconjugants, photosynthesis-deficient mutants were recovered, some of which had elevated beta-galactosidase levels . Among the mutants examined, beta-galactosidase expression was linked exclusively to R751 . Many of the photosynthesis-deficient mutants were found to have alterations in their indigenous plasmids which apparently involved the exchange of DNA from one plasmid to another . Southern blot analysis revealed that there are extensive DNA sequences which are shared by the two plasmids that are involved in the rearrangements and that no exogenous DNA sequences appear to be involved . It was further discovered that plasmid rearrangement is a general phenomenon which can occur spontaneously in R . sphaeroides 2.4.1 and shows a high correlation with a photosynthesis minus phenotype.

J Mol Biol, 1984 May 5, 175(1), 99 - 102
Preliminary X-ray diffraction study of ribulose-1,5-bisphosphate carboxylase from Rhodospirillum rubrum; Schneider G et al.; Crystals from the dimeric enzyme ribulose-1,5-bisphosphate carboxylase of the photosynthetic bacterium Rhodospirillum rubrum have been obtained from the gene product expressed in Escherichia coli . The crystals are of the quarternary complex comprising enzyme: activator CO2 (as a carbamate): Mg2+: 2- carboxyarabinitol -1,5-bisphosphate (as a transition state analog) . X-ray diffraction photographs show symmetry consistent with space group P4(1)2(1)2 or the corresponding enantiomorphic space group . Cell parameters are a = b = 82 A, c = 324 A with two subunits per asymmetric unit . The crystals diffract to at least 3 A resolution.

Mol Biol (Mosk), 1984 May-Jun, 18(3), 719 - 24
{Protein fluorescence of photosynthetic reaction centers from Rhodopseudomonas sphaeroides}; Zakharova NI et al.; Luminescence emitted by tryptophan residues of reaction center (RC) preparations was studied . The RG preparations were isolated from the photosynthetic bacterium Rhodopseudomonas sphaeroides by treatment with lauryl dimethyl amine oxide (LDAO) . After excitation at lambda 280 nm the quantum yield of luminescence is 0,02 . It is shown that 60% of tryptophanyls are located inside the protein globule in the surrounding of relaxating polar groups and the rest approximately 40% on the outer surface of the globule--predominantly in the positively charged region of the LDAO-RC protein--in the surrounding of protein-bound water molecules . There is a correlation between the pH dependencies of the position of the peak of luminescence from tryptophanyls and effectivity of electron transfer from the primary (quinone) to secondary acceptor . The two parameters are invariant at pH from 7 to 9 and vary at pH less than 7 and pH greater than 9 . The phenomena responsible for the observed correlation are discussed on the basis of pH-dependent changes in the RC protein which govern electron transport activity at the reaction center.

J Microsc, 1984 May, 134 ( Pt 2), 213 - 6
Extraction of lipids during freeze-substitution of Acholeplasma laidlawii-cells for electron microscopy; Weibull C et al.; Cells of the bacterium Acholeplasma laidlawii were rapidly frozen against a copper block cooled by liquid helium . The frozen cells were transferred to liquid nitrogen and subsequently to acetone or methanol at 183 K . After 24 h the cells were infiltrated at 203 K with a non-polar methacrylate resin of the same type as Lowicryl HM20 . The resin was cured at the same temperature . Acetone extracted approximately 5% of the lipid content of the cells, methanol 15-45% and the resin only negligible amounts . Similar results were obtained with A . laidlawii-ghosts . The cells appeared well preserved when examined in the electron microscope.

Infect Immun, 1984 May, 44(2), 386 - 93
Isolation of a major cell envelope protein from Fusobacterium nucleatum; DiRienzo JM et al.; A major, heat-modifiable cell envelope protein was identified in Fusobacterium nucleatum FDC 364 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis . This protein, designated HM-1, had apparent molecular weights of 38,500 and 50,000 when heated in sodium dodecyl sulfate at 50 and 100 degrees C, respectively . Whole cells were labeled with 125I, and the results suggested that the HM-1 protein may be exposed on the bacterial surface . The HM-1 protein was isolated in association with the peptidoglycan by extraction of whole cells or cell envelopes with 2% sodium dodecyl sulfate at 55 degrees C . Heating the peptidoglycan-HM-1 protein complex in the detergent at 100 degrees C resulted in the quantitative release of the protein . Isoelectric focusing experiments and amino acid analysis revealed that the HM-1 protein had a basic character and was moderately hydrophilic . Various strains of F . nucleatum as well as three oral fusiform isolates contained a serologically related protein . The abundance and location of the HM-1 protein in F . nucleatum suggest that it has the potential to participate in cell surface-related interactions of this bacterium.

Biochem Biophys Res Commun, 1984 Apr 16, 120(1), 164 - 71
Structure of a bacterial photosynthetic membrane: integrity of reaction centers following proteolysis and detergent solubilization; Jacob JS et al.; The photosynthetic membranes of the purple bacterium Rhodopseudomonas viridis are composed of a semi-crystalline lattice of subunits . Proteolysis of isolated membranes with trypsin or pronase results in the degradation of polypeptides associated with the photosynthetic reaction center . However, two low molecular weight peptides which may form the light-harvesting complex survive the enzymatic treatment . The proteolysis does not affect the major absorbance peak (830 nm) associated with the reaction center . However, treatment of proteolyzed membranes with detergents such as LDAO abolishes the 830 nm absorbance peak . The 830 nm peak is stable following LDAO solubilization of non-proteolyzed membranes . These results suggest that a combination of covalent and non-covalent interactions are important in maintaining the configuration of the reaction center, and are consistent with a model of membrane organization in which the light-harvesting components are buried in a lipid phase of the membrane and reaction center components form the large structures which electron microscope studies have shown to extend from either membrane surface.

J Comp Pathol, 1984 Apr, 94(2), 175 - 81
Bacterial infection of the common bile duct in chronic fascioliasis in the rat; Foster JR; Bile taken from rats infected with the liver fluke, Fasciola hepatica contained spiral bacteria whereas bile from uninfected rats was free from spiral bacteria . The bacterium and its relationship to the bile duct epithelium and the liver fluke was studied with a combination of light microscopy, scanning and transmission electron microscopy . Its morphological characteristics suggest that the bacterium belongs to the genus Spirillum . In contrast to many other co-infections of bacteria and helminths, the present one seems to be a fairly passive relationship so that neither the helminth nor the rat suffers from the presence of bacteria . The presence of the bacteria is thought to be due to changes in the biliary environment, produced as a result of the fluke infection; these changes subsequently allow a multiplication of bacteria normally present in the uninfected animal.

Minerva Med, 1984 Mar 17, 75(11), 535 - 42
{Mycobacterial infections}; Mazzarone R; Author dwells upon the recent acquisitions about Mycobacterial diseases, that can be the clinical emerging problem now that tuberculosis is on the decrease . The natural "habitat" of non tubercular Mycobacteria is external environment . In human pathology there are several possible localizations . The boundary line between infection and disease is not easily identifiable, in that these Mycobacteria tend to infect the already damaged tissues . Author then examines the clinical aspects of pulmonary Mycobacterial diseases, emphasizing their frequent association with other pulmonary diseases . The specificity of cutaneous tests is challenged, since a certain diagnosis of Mycobacterial disease is only made by repeated isolations of bacterium . The therapeutic programme and prognosis are conditioned by Mycobacterial pharmacoresistances and by predisposing host conditions.

Biochem Biophys Res Commun, 1984 Mar 15, 119(2), 549 - 55
Purification of the rice embryo lectin and its binding to nitrogen-fixing bacteria from the rhizosphere of rice; Tabary F et al.; A lectin was purified from rice embryos by aqueous acid extraction of crude embryo powder, followed by ammonium sulfate precipitation, affinity chromatography on agarose p-aminophenyl-beta-D-N-acetylglucosamine and gel-filtration on AcA 54 . Its homogeneity was checked by polyacrylamide gel electrophoresis, gel-filtration and immunological methods . The hemagglutinating activity of the purified rice lectin was 0.02 micrograms/ml . This lectin labelled with {14C} acetic anhydride was shown to interact in vitro with different bacteria isolated from the rhizosphere of rice . The most efficient binding was obtained with Beijerinckia V. . The affinity constant Ka was (1.04 +/- 0.30) X 10(7) M-1 and each bacterium contained 1660 +/- 150 lectin receptor sites . In contrast, no interaction between bacteria isolated from the rhizosphere of maize or E . coli K 12 and rice lectin was evidenced.

Can J Microbiol, 1984 Mar, 30(3), 375 - 80
The effects of the insecticide acephate on the growth and nutrient uptake of an aquatic bacterium; Williams GL et al.; The effects of high (1000 ppm) and low (1 ppm) concentrations of acephate on the rate of growth and nutrient uptake by an aquatic bacterium (identified as Chromobacterium lividum ) were investigated . This insecticide increased doubling time, decreased maximum cellular yield, and reduced cell size when C . lividum was grown in the presence of high acephate concentrations . Total {14C}glucose and 14C-labeled amino acids uptake rates were reduced by the high acephate concentration . The high acephate concentration did not affect active uptake of {14C}cycloleucine, a nonmetabolized amino acid analogue . Low concentration of acephate had little apparent influence upon these metabolic processes.

Am J Med Sci, 1984 Mar-Apr, 287(2), 40 - 2
Histologic demonstration of intradermal spirochetes in a patient with Lyme disease; Kantoff PW et al.; Spirochetal organisms were demonstrated histologically in skin biopsy specimens from a patient with Lyme disease and erythema chronicum migrans . The patient responded rapidly to penicillin G benzathine administration . Convalescent serum contained a high titer of antibody to an lxodes dammini spirochete antigen . The finding of spirochetes in an erythema chronicum migrans lesion in a patient with clinical Lyme disease supports further recent evidence that this illness is an infectious disease caused by a tick-borne bacterium . The skin biopsy may be a useful diagnostic tool in this disease.

Appl Environ Microbiol, 1984 Mar, 47(3), 467 - 71
Proliferation of Legionella pneumophila as an intracellular parasite of the ciliated protozoan Tetrahymena pyriformis; Fields BS et al.; In a series of experiments, we have determined that Legionella pneumophila will proliferate as an intracellular parasite of the ciliated holotrich Tetrahymena pyriformis in sterile tap water at 35 degrees C . After 7 days of incubation, serpentine chains of approximately 10(3) L . pneumophila cells were observed throughout the cytoplasm of the protozoan infected initially with 1 to 30 L . pneumophila cells . The overall L . pneumophila population increased from ca . 1.0 X 10(2) to ca . 5.0 X 10(4) cells per ml in the coculture within this time frame . The interactions between the protozoan and the bacterium appear to depend upon their concentrations as well as temperature of incubation . L . pneumophila did not multiply in sterile tap water alone, in suspensions of lysed T . pyriformis, or in cell-free filtrates of a T . pyriformis culture . In addition to establishing an ecological model, we found that addition of T . pyriformis to environmental specimens served as an enrichment method that improved isolation of legionella from the specimens.

J Immunol, 1984 Mar, 132(3), 1550 - 5
Immunologic memory to phosphocholine . IV . Hybridomas representative of Group I (T15-like) and Group II (non-T15-like) antibodies utilize distinct VH genes; Chang SP et al.; The anti-phosphocholine (PC) memory response elicited in BALB/c mice by phosphocholine-keyhole limpet hemocyanin (PC-KLH) contains two groups of antibodies distinguished by their fine specificity for PC and p-nitrophenylphosphocholine (NPPC) . Group I antibodies are inhibited by both PC and NPPC, while Group II antibodies are inhibited appreciably only by NPPC; only Group I antibodies are dominated by the T15 idiotype . Anti-PC hybridomas representative of the memory response to PC-KLH were produced to examine the variable region genes expressed by memory B cells . Two IgM hybridomas were of the Group I type, because they were inhibited by both PC and NPPC and they bound to the pneumococcus R36A . However, only one of these antibodies (PCM-2) expressed a T15 idiotope, while the other (PCM-1) did not express any of three T15 idiotopes . Despite its negative T15 idiotype profile, N-terminal amino acid sequencing of PCM-1 purified heavy chain and Southern blots of the hybridoma DNA indicated that it utilizes the T15 VH and JH1 genes . Three hybridomas, IgG1, IgM, and IgE, typical of Group II antibodies, were examined; these were negative for three T15 idiotopes and displayed measurable avidity only for NPPC in a PC-protein binding inhibition assay . These three hybridoma antibodies, like serum Group II IgG1, did not measurably bind to the bacterium R36A . The heavy chain amino termini of all three of these antibodies were inaccessible for Edman degradation . Southern blots of DNA from the IgG1 hybridoma revealed the T15 VH gene to be in the germ line configuration only and unassociated with any JH segment, indicating that this Group II antibody utilizes a VH gene different from the T15 family . These results signify that, whereas some diversity of the (anti-PC) memory response may be generated by somatic diversification of variable regions important in the primary response, a significant contribution to the overall heterogeneity of memory antibodies originates in the expression of additional variable region genes.

Arch Biochem Biophys, 1984 Mar, 229(2), 640 - 9
Uncoupler-stimulated Na+ pump and its possible role in the halotolerant bacterium, Ba; Ken-Dror S et al.; In cells of Ba1 suspended in K salt as the osmoticum, the respiratory rate declined by 80% between the pH values of 6.5 and 8.5 . Catalytic amounts of Na+ ions prevented this drop . The possibility that Na+ exerted its effect by an influence on proton fluxes across the membrane (Na+/H+ exchange) was explored . Addition of catalytic amounts of Na+ ions to cells respiring at pH 8.5 elicited an influx of protons and, as a result, the delta pH across the membrane became diminished . delta psi (membrane potential) was not affected by Na+ . At pH 6.5, Na+ caused no proton influx . FCCP (carbonylcyanide-p-trifluoromethoxyphenylhydrazone) collapsed delta psi, but the Na+-dependent proton influx observed at pH 8.5 became enhanced, leading to an inversion of delta pH (more acid inside) . When a Na salt was used as the osmoticum, delta pH of reversed polarity was generated by respiration also in the absence of FCCP . Respiring, inverted membrane vesicles responded to a Na+ pulse essentially as the intact cells . Based on the above and some additional findings it is suggested that these Na+-dependent effects are suited to prevent a raise in the intracellular pH over the level which hinders the respiratory activity . It may also play a role in the regulation of intracellular Na salt content.

J Bacteriol, 1984 Mar, 157(3), 979 - 83
Molecular construction and characterization of nif mutants of the obligate methanotroph Methylosinus sp . strain 6; Toukdarian AE et al.; We describe here a method for constructing mutants in bacteria that are not amenable to mutant isolation by conventional means . A one-step marker exchange procedure was used to construct nitrogen fixation (nif) mutants of the obligate methane-utilizing bacterium Methylosinus sp . strain 6, using transposon 5 (Tn5)-containing nif genes cloned into pBR325 . The resultant mutants appeared to contain defects in nif structural genes, and DNA hybridization analysis showed that although one out of five had apparently been produced as a result of double-crossover homologous recombination, a variety of molecular events had led to the production of the other four mutants.

Biochem J, 1984 Feb 15, 218(1), 269 - 72
Cleavage of formate from omega,4-dihydroxyacetophenone . An unusual oxygen-requiring reaction in the bacterial catabolism of 4-hydroxyacetophenone; Hopper DJ et al.; An enzyme, from a soil bacterium grown on 4-hydroxyacetophenone, cleaved the side chain of omega,4-dihydroxyacetophenone between the keto group and the carbon atom bearing a hydroxy group to give 4-hydroxybenzoate and formate . The reaction was O2-dependent . Partially purified enzyme required no added cofactors for activity.

Eur J Biochem, 1984 Feb 15, 139(1), 173 - 80
Separation and analysis of novel polyunsaturated mycolic acids from a psychrophilic, acid-fast bacterium, Gordona aurantiaca; Tomiyasu I et al.; More than 30 molecular species of highly unsaturated mycolic acids, ranging from C60 to C78 and possessing between two and seven double bonds, have been obtained from a new genus of acid-fast bacteria, Gordona aurantiaca . They were fully separated and identified as their trimethylsilyl ether derivatives by a combination of silica gel thin-layer chromatography (TLC), argentation thin-layer chromatography and gas chromatography/mass spectrometry (GC/MS) . On silica gel thin-layer chromatography two adjacent spots, corresponding to mycolic acids possessing different structures of straight-chain and alpha-alkyl branch, were detected . The lower spot was separated by argentation TLC into four subclasses: monoenoic (including a small amount of saturated), dienoic, trienoic and tetraenoic mycolic acids ranging from C62 to C74 and possessing a C16:0, C18:0 or C20:0 alkyl branch at the C-2 position . The upper spot was separated by argentation TLC into five subclasses: dienoic (including a small amount of monoenoic), trienoic, tetraenoic, pentaenoic and hexaenoic (heptaenoic) acids ranging from C64 to C78 and possessing a C18:1 or C20:1 alkyl branch at the C-2 position . These types of mycolic acid structure differ from those reported previously in Mycobacteria and Nocardia, in the numbers of both carbon atoms and double-bonds and the intermediate length of the alpha-alkyl branch . The characteristic polyenoic structure of the straight-chain alkyl unit was also confirmed by GC/MS analysis of the meromycolaldehydes obtained after pyrolysis of the methyl mycolates . The major aldehydes obtained from the lower-spot mycolic acids were C44, C46, C48, C50 and C52, while those from the upper-spot mycolic acids were C48, C50, C52, C54 and C56, centering at C54 . These aldehydes were also shown to possess between two and four double bonds in the lower-spot and between two and seven double bonds in the higher-spot mycolic acids, respectively . The physiological role of such highly polyunsaturated mycolic acids in psychrophilic acid-fast bacteria is discussed.

Biochem Biophys Res Commun, 1984 Feb 14, 118(3), 964 - 9
Isolation and characterization of cytochrome C1 from photosynthetic bacterium Rhodopseudomonas sphaeroides R-26; Yu CA et al.; Cytochrome c1 of photosynthetic bacterium R . sphaeroides R-26 has been purified from isolated cytochrome b-c1 complex to a single polypeptide, using a procedure involving Triton X-100 and urea solubilization, calcium phosphate column chromatography and ammonium sulfate fractionation . The purified protein contains 30 nmoles heme per mg protein and has an apparent molecular weight of 30,000, as determined by sodium dodecylsulfate polyacrylamide gel electrophoresis . Bacterial cytochrome c1 is soluble in aqueous solution in the absence of detergent and has spectral characteristics similar to mammalian cytochrome c1 . The amino acid compositions of these two proteins, however, are not comparable.

Biophys J, 1984 Feb, 45(2), 455 - 61
Light saturation curves and quantum yields in reaction centers from photosynthetic bacteria; Cho HM et al.; Reaction centers isolated from the photosynthetic bacterium Rhodopseudomonas sphaeroides R-26 mutant were irradiated with laser pulses of variable energy and the amount of photooxidation of the primary electron donor bacteriochlorophyll was measured . The resultant light saturation curve fits an exponential function and not a hyperbolic or hyperbolic tangent function . Analysis using either a Poisson statistical model or a simple kinetic model predicts an exponential light saturation curve in the limit where the light pulse is long relative to any transient intermediate states . The absolute quantum yield of photochemistry was found to be 0.98, utilizing the entire light saturation curve . Distortions from the simple exponential light saturation behavior are predicted when very short laser pulses are used.

J Biochem (Tokyo), 1984 Feb, 95(2), 575 - 9
X-ray diffraction studies on photosystem I fragments from a blue-green alga, Anabaena variabilis, and spinach; Tsukamoto Y et al.; Photosystem I fragments were prepared from thylakoid membranes of a blue-green alga (Anabaena variabilis) and spinach by treatment with a detergent, Triton X-100 . Equatorial X-ray diffraction patterns were recorded on films for oriented specimens of thylakoid membranes and photosystem I fragments . The thylakoid membranes and photosystem I fragments gave essentially the same equatorial diffraction patterns in both Anabaena variabilis and spinach, indicating that the major X-ray scatterers in these thylakoid membranes are the molecular assembly of photosystem I . The equatorial X-ray diffraction from the photosystem I fragments of Anabaena variabilis and spinach extends to the reciprocal space of 1/7 A-1 . The diffraction pattern exhibits six to nine distinct maxima though they are diffuse, indicating that the arrangement of the constituent molecules in photosystem I has a definite geometrical regularity . The radial autocorrelation functions indicate that the maximal sizes of photosystem I in these thylakoid membranes are about 100 A, and the geometrical regularity does not correspond to a crystalline order . The X-ray diffraction patterns from photosystem I fragments from Anabaena variabilis and spinach are quite similar to each other, suggesting the possibility that the molecular structures of photosystem I in Anabaena variabilis and spinach have a fundamental similarity . These diffraction patterns, however, are different from that of the chromatophore obtained from a photosynthetic bacterium, Rhodospirillum rubrum.

Eur J Biochem, 1984 Feb 1, 138(3), 611 - 5
The effect of EDTA and related chelating agents on the oxidation of methanol by the methylotrophic bacterium, Methylophilus methylotrophus; Carver MA et al.; The effects of EDTA and related metal-chelating agents on the respiratory system of the methylotrophic bacterium Methylophilus methylotrophus have been investigated . EDTA completely inhibited whole cell methanol oxidase activity and concomitantly decreased the aerobic steady-state reduction level of cytochrome c, but only partially inhibited methanol dehydrogenase activity . Analysis of the inhibition kinetics of EDTA and other chelating agents on methanol oxidase activity indicated that they were effective in the order CDTA greater than EDTA greater than HEDTA greater than EGTA greater than EDDA, and that they inhibited in an uncompetitive manner . Inhibition by EDTA varied as a function of the ambient cell mass in the assay, and could be partly reversed by the addition of divalent cations . EDTA had no effect on the activity of solubilised methanol dehydrogenase . These and other results indicate that EDTA binds a divalent metal ion, probably Mg2+, which is involved in the functional association of methanol dehydrogenase with the respiratory membrane . This concept is discussed in terms of the electron transfer properties and spatial organisation of the terminal respiratory chain of M . methylotrophus.

Eur J Biochem, 1984 Feb 1, 138(3), 509 - 18
Synthesis of pigment-binding protein in toluene-treated Rhodopseudomonas capsulata and in cell-free systems; Dierstein R; Pigment-binding protein of the facultatively phototrophic bacterium Rhodospeudomonas capsulata could be selectively synthesized in toluene-treated cells as well as in homologous and heterologous cell-free translation systems by isolated polysomes . It is shown that the pigment-binding polypeptides of the light-harvesting complexes are encoded by messenger RNA of extreme longevity . The dependence of their synthesis on the concomitant synthesis of tetrapyrroles was demonstrated in the toluene-treated cells . The large Mr-28 000 polypeptide of the reaction center and the Mr-10 000 pigment-binding polypeptide of the light-harvesting complex II were found to be synthesized by free (water-soluble) polysomes without a cleavable 'leader' or 'signal' peptide {reviewed by W . Wickner (1979) Annu . Rev . Biochem . 48, 23-45} . The Mr-10 000 polypeptide, as synthesized in vitro, was studied in more detail . Unlike the membrane-assembled polypeptide in vivo it was insoluble in an organic solvent mixture (chloroform/methanol 1:1, v/v) . After detergent denaturation in the presence of membrane isolated from the organism it became organic-solvent-soluble . Obviously the polypeptide could be induced to assume alternative conformations in which its apolar residues were either exposed to the solvent or buried within . These findings, in agreement with Wickner's hypothesis, indicate that the Mr-10 000 polypeptide may enter the lipid bilayer by a 'membrane-triggered' conformational change.

Immun Infekt, 1984 Feb, 12(1), 13 - 9
{Current theories of phagocytosis and methodological problems in the study of phagocytosis defects in diabetics}; Horn W; The process of phagocytosis on bacteria is described: recognition of the bacterium by C3b- and Fc-receptors and possibly lektin-like substances on PMN surfaces; ingestion by an actin-myosin interaction in a local Ca++ gradient; simultaneous activation of a NADPH-oxidase and oxidative attack of the bacterial membrane . Special aspects: opsonization, dependence of the rate of phagocytosis on day-time, conditions of diabetics.

J Mol Biol, 1984 Jan 5, 172(1), 109 - 39
Refined structure of cytochrome c3 at 1.8 A resolution; Higuchi Y et al.; The structure of cytochrome c3 from the sulfate-reducing bacterium Desulfovibrio vulgaris Miyazaki has been successfully refined at 1.8 A resolution . The crystallographic R factor is 0.176 for 9907 significant reflections . The isotropic temperature factors of individual atoms were refined and a total of 47 water molecules located on the difference map were incorporated in the refinement . The four heme groups are closely packed, with adjacent pairs of heme planes being nearly perpendicular to each other . The fifth and the sixth ligands of the heme iron atoms are histidine residues with N epsilon 2-Fe distances ranging from 1.88 A to 2.12 A . The histidine co-ordination to the heme iron is different for each heme group . The heme groups are all highly exposed to solvent, although the actual regions exposed differ among the hemes . The four heme groups are located in different environments, and the heme planes are deformed from planarity . The differences in the heme structures and their environments indicate that the four heme groups are non-equivalent . The chemical as well as the physical properties of cytochrome c3 should be interpreted in terms of the structural non-equivalence of the heme groups . The characteristic secondary structural non-equivalence of the heme groups . The characteristic secondary structures of the polypeptide chain of this molecule are three short alpha-helices, two short beta-strands and ten reverse turns.

J Wildl Dis, 1984 Jan, 20(1), 21 - 6
Antibodies to spirochetes in white-tailed deer and prevalence of infected ticks from foci of Lyme disease in Connecticut; Magnarelli LA et al.; White-tailed deer (Odocoileus virginianus) were examined for the tick, Ixodes dammini, and sera were analyzed for antibodies to spirochetes during 1982 . Of the 323 animals inspected in four areas endemic for Lyme disease, 188 (58%) had adult ticks; parasitism ranged from 43% at Haddam to 82% at East Lyme . Direct and indirect fluorescent antibody tests detected spirochetes in 18 of 133 (14%) ticks . Indirect immunofluorescence tests revealed antibodies at titers of 1:64-1:4,096 to this bacterium in 93 (28%) of the 332 sera assayed . There is a close correlation among the distribution of spirochete-infected I . dammini, deer with antibodies, and human cases of Lyme disease.

J Comp Pathol, 1984 Jan, 94(1), 25 - 32
Infection with Dermatophilus congolensis at a contact hypersensitivity site and its relevance to chronic streptothricosis lesions in the cattle of West Africa; Davis D; Guinea-pigs were sensitized to CDNB and infected with D . congolensis at the site of a subsequent application of this chemical . The bacterium was recovered from the skin over a longer period of time in sensitized individuals than in nonsensitized controls . Animals rendered tolerant to the chemical gave lower yields of bacteria than sensitized animals . However, the lesions produced at the site of infection did not become chronic . The growth of D . congolensis at a contact hypersensitivity site may possibly simulate infection in skin following an arthropod bite and be relevant to the pathogenesis of chronic streptothricosis lesions in the cattle of West Africa.

J Clin Microbiol, 1984 Jan, 19(1), 30 - 3
Legionella bozemanii serogroup 2: a new etiological agent; Tang PW et al.; A newly discovered bacterium, Toronto 3, isolated from a lung aspirate of a patient with pneumonia, has been characterized . The isolate was identified as Legionella bozemanii by chemical data from cellular fatty acid and ubiquinone analyses and by DNA relatedness studies . The isolate, however, differs phenotypically from L . bozemanii by its colonial characteristics and strong interspecies serological cross-reactions, which are unique among clinical isolates of legionellae . The name L . bozemanni serogroup 2 is proposed . The reference strain is Toronto 3 . The clinical illness caused by L . bozemanii serogroup 2 was not distinguishable from other Legionella infections . L . bozemanii is the third Legionella species with more than one serogroup . Rapid laboratory diagnosis of this strain by direct fluorescent antibody test may be complicated in the absence of culture isolation.

Immunol Commun, 1984, 13(3), 211 - 27
Nonspecific cell surface properties: contact angle of water on dried cell monolayers; Mege JL et al.; Measuring contact angle of water on dried cell or bacterium monolayers allowed van Oss (1) and others (2) to find a correlation between particle hydrophobicity and ingestion by phagocytic cells . The present study was undertaken to understand what was actually assayed with this method . Monolayers were prepared with different cell types at different densities, and they were dried under atmospheres with varying humidity before being studied with scanning electron microscopy and contact angle techniques . It is concluded that a) contact angles are independent of the cell density and substrate structure when more than 30% of the substrate area is covered with cells . b) Initial cell shape should not influence contact angle . c) Contact angles are markedly dependent on the nature of tested cells . d) Contact angles are substantially influenced by the cell drying procedure . e) A very small fraction of the energies we measured would be sufficient to account for cell-cell interactions . Hence these might play a role in some situations of biological interest.

Arch Oral Biol, 1984, 29(5), 349 - 52
The pattern of experimental colonization of a human and a rodent strain of the bacterium Actinomyces viscosus on the dentition of the rat; de Jong MH et al.; Samples were taken from mesial, buccal, lingual and approximal sites and from fissures . Initially, most A . viscosus were recovered from the retention sites . With the exception of lingual sites during the period of exponential growth, the apparent doubling times calculated for A . viscosus Nyl SR remained within narrow limits for all locations . After cessation of exponentional growth, both strains had colonized all surfaces . However, the rodent strain A . viscosus Nyl SR had formed 30-800 times larger populations on the smooth surfaces than the human strain A . viscosus Ut2 . On the retention sites, the populations of both strains were not significantly different.

Antonie Van Leeuwenhoek, 1984, 50(3), 261 - 8
Gemmata obscuriglobus, a new genus and species of the budding bacteria; Franzmann PD et al.; A single strain of a budding bacterium was isolated from freshwater . The strain had a life-cycle, with a multitrichous swarmer stage, and produced a phase-dark inclusion of packed ribosomes and nuclear material . The mol % G + C of the DNA was 64.4 +/- 1.0 . A new genus, Gemmata with the type species Gemmata obscuriglobus is proposed . The type strain is UQM 2246.

J Wildl Dis, 1984 Jan, 20(1), 27 - 30
Experimental infection of gray foxes (Urocyon cinereoargenteus) with Brucella abortus; Scanlan CM et al.; Ten gray foxes, eight principals that were fed approximately 4.4 X 10(10) colony forming units of Brucella abortus strain 2308 and two controls, were examined for serologic responses and tissue distribution of the organisms . Blood sera from each fox were tested on the day of exposure and at seven weekly intervals for antibodies to B . abortus, using the brucellosis card, standard tube agglutination, 2-mercaptoethanol and rivanol tests . Control foxes were serologically negative for all tests throughout the study and the principals were negative prior to exposure . On days 14, 21 and 28, the eight principals had positive card reactions and greater than or equal to 1:100 tube agglutination titers . After 28 days, the titers receded; and by day 49, three principals had negative card reactions and one of these was negative for all tests . Brucella abortus was isolated from one or more lymph nodes from seven of eight principals including the one which was seronegative . The bacterium was not isolated from lungs, livers, spleens, kidneys, uteri or testicles.

J Gen Microbiol, 1984 Jan, 130 ( Pt 1), 193 - 201
Control mechanisms governing the infectivity of Chlamydia trachomatis for HeLa cells: the role of calmodulin; Murray A et al.; Adhesion of the obligate intracellular bacterium Chlamydia trachomatis to host cells is associated with a flux of Ca2+ across the cell membrane, and infection is enhanced by treatment of host cells with Ca2+ ionophore . The possibility that Ca2+ might interact with host cell Ca2+ regulatory proteins to promote chlamydial infection was investigated . Treatment of HeLa 229 cells with the calmodulin inhibitors pimozide, trifluoperazine, chlorpromazine, promethazine or haloperidol reduced chlamydial infectivity as measured by inclusion counting or the specific incorporation of {3H}threonine . The inhibitory effect was reversible, dose-related and shown to be associated with impairment of chlamydial adhesion and uptake by the host cells . This effect was clearly distinguished from the delayed maturation of chlamydiae due to continuous exposure to calmodulin inhibitors which may result from a decrease in the availability of high energy compounds from the host cells necessary for chlamydial growth . The possible mechanisms for calmodulin-mediated chlamydial endocytosis are discussed.

Arch Oral Biol, 1984, 29(9), 739 - 43
Bacteriocin activity of the bacterium Bacterionema matruchotii isolated from dental plaque in man; Nakamura T et al.; Production of bacteriocin by five strains of Bacterionema matruchotii isolated from dental plaque was confirmed . It was detected in the culture supernatant and inhibited the growth of various species of oral indigenous bacteria . The bacteriocin adsorbed only to sensitive cells.

J Cell Biochem, 1984, 24(3), 243 - 59
Herbicide-quinone competition in the acceptor complex of photosynthetic reaction centers from Rhodopseudomonas sphaeroides: a bacterial model for PS-II-herbicide activity in plants; Stein RR et al.; A select group of herbicides that inhibit photosystem II also act at the acceptor side of the reaction center (RC) from the photosynthetic bacterium Rhodopseudomonas sphaeroides, with much the same relative specificity as in plants . These include the triazines and some phenolic compounds . The proposal that herbicides inhibit the electron transfer from the primary quinone (QA) to the secondary quinone (QB) by competing for the secondary quinone binding site--the B-site--{5}, is tested here with terbutryn, the most potent of the triazines . Competition between terbutryn and ubiquinone (Q-10) was observed using the kinetics of the back-reaction as a measure of inhibition . The model includes binding equilibria before and after flash activation . The binding constants for the preflash (dark) equilibria, for reaction centers in 0.14% lauryl dimethylamine-N-oxide (LDAO), were KDi = 0.8 microM terbutryn, KDq = 2 microM Q-10; both are detergent-concentration dependent . After flash activation, binding equilibrium is not fully restored on the time scale of the back-reaction because terbutryn unbinds slowly . This gives rise to biphasic decay kinetics from which koff for terbutryn was estimated to be 3 sec-1 . Titrations of the rate of the slow back reaction indicated that the post-flash equilibrium is less sensitive to inhibitor, in a manner that is independent of the much stronger binding of the semiquinone, Q-B, and indicative of a direct effect of the redox state of QA on the affinity of the B-site for ligands . However, the effects on KLi and KDq could not be separated: either KLi greater than KDi or KLq less than KDq . Some triazine-resistant mutants have been isolated and are described . All appear to be herbicide binding site mutants . Whole cells and photosynthetic membrane vesicles (chromatophores) exhibit a 10-50-fold increase in resistance to triazines due, in large part, to an increase in the rate of unbinding (koff) . The modifications of the binding site appear to diminish the affinity of the B-site for ubiquinone as well as terbutryn . It is concluded that bacterial RCs are a useful model for the study of herbicide activity and specificity.

Acta Obstet Gynecol Scand, 1984, 63(3), 203 - 5
Genital colonization by Actinomyces israelii and serologic immune response to the bacterium after five years use of the same copper intra-uterine device; Persson E et al.; An increased risk of developing genital actinomycosis has been found with long-term use of IUDs . In this study a group of women who had used their IUDs for 60 +/- 6 months was compared with a group having worn their IUDs for 36 +/- 6 months . None of the women examined had symptoms of genital infection . No significant differences could be found in colonization frequency of A . israelii on the IUDs or in humoral antibody response to the bacterium.

Arch Surg, 1984 Jan, 119(1), 90 - 5
Acquired immune deficiency syndrome . A surgical perspective; Davis JM et al.; Eighty-nine lymph node biopsies were performed on 82 patients with lymphadenopathy, immunosuppression, and possible acquired immune deficiency syndrome . The 21 patients with diagnoses of lymphoma or Kaposi's sarcoma were older, had more sexual contacts, and were sexually active for more years than patients with benign diagnoses . Cytomegalovirus and Epstein-Barr viral titers were elevated in both groups but were not significantly different in the benign and malignant groups . Skin flora were cultured from lymph node tissue in 24.7% of the patients . Two patients (2.5%) had wound infections with the same bacterium present in the lymph node culture, while 66 patients initially had two different benign pathologic patterns . Fifty-six patients had explosive follicular hyperplasia, and ten had follicular involution . Four of the patients with follicular involution and one with follicular hyperplasia subsequently had malignant tumors.

Int J Biochem, 1984, 16(3), 315 - 21
Inorganic pyrophosphatase--II . Purification and studies of some properties of the enzyme isolated from thermophylic bacterium Thermus flavus 70 K; Kasho VN et al.; Inorganic pyrophosphatase was isolated from T . flavus in a homogeneous form with a specific activity of 400 U/mg . The enzyme has an isoelectric point 5.0 and consists of 4 subunits each of 24,000 mol . wt . Pyrophosphatase possesses high thermal stability . The enzyme can hydrolyze PPi, ATP and p-nitrophenylphosphate . Kinetic constants of the enzyme's interaction with the metal-activator and metal-substrate complex have been estimated.

Biotechnol Genet Eng Rev, 1984, 1, 223 - 59
Biotechnological approach to a new foot-and-mouth disease virus vaccine; Kupper H; Major contributions towards the development of an absolutely safe FMDV vaccine are evident . With the identification of VP1 as the immunogenic protein, it is possible to manufacture a subunit vaccine via biotechnology . DNA sequences encoding the VP1 protein can be introduced into a bacterium with ease; under the appropriate conditions, large amounts of VP1 can be produced in a short time . The accumulation of amino acid sequences generated by recombinant DNA techniques allows identification of antigenic domains, which are the basis of variability among serotype and subtype viruses . As a result, vaccine production by chemical synthesis of short peptides corresponding to the antigenic determinants is greatly facilitated . At present, results from experimental vaccines employing genetically engineered or chemically synthesized VP1 antigens against homologous virus infection are encouraging . The current approach of preparing vaccine is to utilize the antigenic specificity of the virus . Since FMDV undergoes antigenic drift, variants not neutralized by type-specific serum will arise . An alternative approach is to prepare vaccines based on antigenic sites shared among all serotype and subtype viruses.

Biochim Biophys Acta, 1983 Dec 19, 763(4), 435 - 6
Nuclear magnetic resonance studies of Ba1 bacterium and some model systems; Goldberg M et al.; Lithium NMR relaxation times of some model systems and E . coli cells in high LiCl concentration were measured . The lithium NMR relaxation times were compared to the relaxation times in the holotolerant bacterium Ba1 (Goldberg, M., Risk, M . and Gilboa, H . (1983) Biochim . Biophys . Acta 763, 35-40) . Complementary studies of the water protons NMR relaxation times were carried out . It is suggested that the lithium in the H.S . Ba1 bacterium is occulated in small pores of the cell envelope.

JAMA, 1983 Dec 16, 250(23), 3225 - 6
Landmark perspective: Tularemia; Sanford JP; The landmark studies on tularemia by Dr Francis have been recognized by designating the causative organism Francisella tularensis rather than Bacterium tularense . A review of his original 1925 article clearly demonstrates the lasting value of critical clinical, epidemiologic, and laboratory studies . Except for expansion of knowledge concerning some aspects of the epidemiology and clinical spectrum and advances in treatment and prevention, the 1925 article is as contemporary as the current literature and textbooks.

Eur J Biochem, 1983 Dec 1, 137(1-2), 155 - 61
The lipopolysaccharide of a chloridazon-degrading bacterium; Weisshaar R et al.; Lipopolysaccharide of a chloridazon-degrading bacterium was obtained by a two-stage extraction procedure with phenol/EDTA in a yield of 0.3% of dried bacteria . The carbohydrate moiety consisted of heptose, 3-deoxyoctulosonic acid and D-glucose in a molar ratio of 1:2:2 X 3 . Lipid A was composed of 1 mol 2,3-diamino-2,3-dideoxy-D-glucose, 2 mol amide-bound and 2.6 mol ester-bound fatty acids/mol . Amide-bound fatty acids were 3-hydroxydodecanoic acid and 3-hydroxyhexadecanoic acid; dodecanoic acid and R-(-)-3-hydroxydodec-5-cis-enoic acid were found to be present in ester linkage . Under conditions of acidic hydrolysis, the latter was converted into the cis and trans isomers of 5-hexyltetrahydrofuran-2-acetic acid . Dodecanoic acid was demonstrated to be linked with the hydroxy groups of the amide-bound fatty acids . The taxonomic significance of these results, especially the demonstration of 2,3-diamino-2, 3-dideoxy-D-glucose, is discussed.

J Bacteriol, 1983 Dec, 156(3), 1352 - 5
Cytoplasmic pH homeostasis in an acidophilic bacterium, Thiobacillus acidophilus; Zychlinsky E et al.; The cytoplasmic buffering capacity of Thiobacillus acidophilus (along with membrane properties) is responsible for the cytoplasmic pH homeostasis in metabolically compromised cells . When a large influx of H+ occurs, the cytoplasmic buffering capacity prevents drastic changes in pH; in addition, this influx, by increasing the positive membrane potential, eventually leads to a cessation of further H+ influx.

J Biochem (Tokyo), 1983 Dec, 94(6), 1815 - 26
Chemical nature of protein complex of photoreaction unit including reaction center in chromatophores of photosynthetic bacterium, Rhodospirillum rubrum, as detected by successive dissociation method; Tanaka K et al.; Reaction center of chromatophores of Rhodospirillum rubrum consists of three kinds of protein, H-, M-, and L-subunit, and is bound with many other kinds of protein to form a larger protein complex (PRU; photoreaction unit), which contains all the bacteriochlorophyll . In the present study, purified PRU was dissociated in a stepwise manner in the presence of various mixtures of lithium dodecyl sulfate, sodium cholate and/or sodium deoxycholate, and separated into five, smaller protein complexes (PL1, PL2, PL3, PL4, and PL4') by high-speed molecular-sieve chromatography . The protein complexes were analyzed for molecular mass (Mm), protein composition, and molecular weights of the constituent proteins by the chromatography described above and by lithium or sodium dodecyl sulfate-polyacrylamide gel electrophoresis . The results suggest that PRU consisted of 1 molecule each of 40K, 39K, 31K (H-subunit), 25K (M-subunit), and 22K (L-subunit), about 12 molecules each of 12K (light-harvesting bacteriochlorophyll-protein) and 11K, and about 6 molecules each of 10K and 9K (the protein nomenclature refers to the apparent molecular weights); the measured and calculated Mm values were 650K and 547K, respectively . The compositions of the other protein complexes were as follows . PL1 = PRU-10K-9K (measured & calculated Mm, 520K & 409K); PL2 = PL1-39K (340K & 267K); PL3 = PL2-40K (160K & 147K); PL4 = PL3-31K-25K (90K & 82K); PL4' = 31K + 25K + 22K (inactivated reaction center) (90K & 78K) . The molar ratios of 12K and 11K to 25K were lower in the dissociated protein complexes than in PRU, and they differed from one complex to another . The locations of the constituent proteins in PRU are discussed.

Antonie Van Leeuwenhoek, 1983 Dec, 49(6), 513 - 36
A deterministic model for monophasic growth of batch cultures of bacteria; Jason AC; Experimental observations of bacterial numbers employing high resolution electrical conductance measurements of the culture provide the basis for a proposed deterministic model of monophasic growth of populations in batch culture . The model postulates that the production and growth of each bacterium is accompanied by the generation of a constant mass of toxic end-products and that specific growth rate declines in proportion to the ratio of the accumulated mass of these substances to the dry mass of the nutrient medium when the substrate is non-limiting . The theoretical relationship is found to fit extensive data for Escherichia coli (NCIB 9132) very closely and offers an analytical basis for the logistic curve frequently observed to represent the time-dependence of growth . These data incidentally provide substantial evidence that lag time and generation time are each independent of both inoculum number and concentration of the medium.

Immunobiology, 1983 Dec, 165(5), 421 - 31
Polymorphonuclear leukocyte regulation of lymphocyte proliferation and differentiation; Fitzgerald J et al.; The polymorphonuclear neutrophil (PMN) regulates in vivo and in vitro immune responses . We report that the immunoenhancing properties of PMN culture supernatants from PMN recruited by the bacterium Actinomyces viscosus (AV) show its exclusive effects on the T cell lymphocyte population . A study of the effect of PMN supernatants on normal Balb/c splenocytes to T and B cell mitogens showed enhancing effects on T cell mitogens, but no effect on B cell mitogen responses when compared to a control . Adherent cells (macrophages) were not required for the enhancing effect, indicating that the supernatant worked directly on the T cell . Proliferation of El-4, a Lyt-1.2 positive lymphoma helper cell, was directly affected by these supernatants . Functionally, T cell-dependent plaque-forming cell responses to sheep red blood cells (SRBC) were enhanced . The polyclonal, T cell-independent plaque-forming cell response was unaffected when generated with LPS as assayed with Protein-A-SRBC . These results indicate that PMN supernatants from cells recruited by AV act on a helper T cell population to enhance both proliferation and differentiation in lymphocyte populations . These interactions provide insight into local inflammatory responses of PMN-lymphocyte infiltration with altered cell-mediated immunity.

FEBS Lett, 1983 Nov 28, 164(1), 185 - 90
The lactose carrier of Escherichia coli functionally incorporated in Rhodopseudomonas sphaeroides obeys the regulatory conditions of the phototrophic bacterium; Elferink MG et al.; Rhodopseudomonas sphaeroides was provided with the ability to transport lactose via conjugation with a strain of Escherichia coli bearing a plasmid containing the lactose operon (including the lac Y gene, coding for the lactose carrier or M protein) and subsequent expression of the lac operon in Rps . sphaeroides (Nano, F.E . and Kaplan, S . submitted) . The initial rate of lactose transport in Rps . sphaeroides was studied as a function of the light intensity and the magnitude of the proton-motive force . The results demonstrate that lactose transport is regulated by the rate of cyclic electron transfer in the same way as the endogenous transport systems.

J Biol Chem, 1983 Nov 25, 258(22), 13768 - 71
Spectral evidence for the existence of a second cytochrome o in whole cells of Vitreoscilla; DeMaio RA et al.; Cytochrome o, a protoheme IX pigment, has been proposed as the terminal oxidase of the filamentous bacterium, Vitreoscilla . Aerobic and anaerobic photolysis of CO-liganded whole cells demonstrated the presence of a second CO-reactive pigment, cytochrome o' . At temperatures lower than -100 degrees C, anaerobic photolysis dissociated only about 25% of the total CO-liganded components to reveal the unliganded cytochrome o' . At these temperatures, the photolysis of cytochrome o could not be demonstrated . At warmer temperatures, recombination of CO with the reduced cytochrome o' occurred with an apparent energy of activation of 5.8 kcal/mol . Aerobic photolysis of whole cells demonstrated two oxygen-bound intermediates . At temperatures lower than -95 degrees C, a spectrally distinct compound with absorption maxima at 428, 534, and 564 nm appeared (form I'); the apparent second order rate constant (k+1) for the formation of this intermediate was found to be 9.1 M-1 s-1, the reverse rate (k-1) was 9.9 X 10(-5) s-1, and the equilibrium constant (Kd) was 1.1 X 10(-5) M . This oxygen intermediate of cytochrome o' is spectrally and kinetically similar to the oxygen intermediate of cytochrome o seen in Escherichia coli . At temperatures warmer than -90 degrees C, photolysis of aerobic samples resulted in the immediate formation of a second oxygen-bound intermediate (form I) with absorption maxima at 422, 534, and 564 nm . This second intermediate results from the binding of oxygen to the cytochrome o (oxygenated cytochrome o) . These data support the proposal that whole cells of Vitreoscilla contain two alternative pathways of electron transport, one terminating with cytochrome o and the other with cytochrome o'.

J Biol Chem, 1983 Nov 10, 258(21), 13034 - 42
Altered acyltransferase activity in Escherichia coli associated with mutations in acyl coenzyme A synthetase; Greenway DL et al.; Growth of a temperature-sensitive general fatty acid synthesis mutant of Escherichia coli K12 at its restrictive temperature in the presence of exogenous palmitate results in lysis of the bacterium . Under these conditions, palmitate is incorporated into membrane phospholipid to a high level . Mutants of bacteria restricting this incorporation (having a palmitate-resistant phenotype) have been isolated and one such mutant, strain L8-2/3, has been further characterized . This mutant has lowered acyl-CoA synthetase (fadD) activity (25-33% of normal) and consequently is defective in fatty acid uptake . This lowered uptake could explain the palmitate-resistant phenotype of strain L8-2/3 . However, both in vivo (fatty acid composition and positional distribution data) and in vitro (acyltransferase activity measurements) experiments suggest that this mutant is also altered in its acyltransferase activities . The mutation(s) of strain L8-2/3 appears to allow increased (approximately 2-fold) incorporation of myristate (and possible unsaturated fatty acids) into position 2 of 1-acyl-sn-glycerol 3-phosphate but normal palmitate incorporation into the same position . The incorporation of palmitate, myristate, and oleate into position 1 of sn-glycerol 3-phosphate by strain L8-2/3 is also higher than that observed with the parent, strain L8-2 . Replacing the partially defective fadD gene of strain L8-2/3 with a wild type allele conferred on this strain the palmitate sensitivity and the acyltransferase activity of the parent strain L8-2 . This finding, taken together with other data, suggests that acyl-CoA synthetase interacts with the acyltransferase(s) in some manner to influence the fatty acid specificity of the acyltransferase.

Xenobiotica, 1983 Nov, 13(11), 689 - 700
Cysteine conjugate beta-lyase in the gastrointestinal bacterium Fusobacterium necrophorum; Larsen GL et al.; A cysteine conjugate beta-lyase from the anaerobic gastrointestinal bacterium Fusobacterium necrophorum was purified 51-fold by heat treatment, ammonium sulphate fractionation, gel-filtration chromatography, and anion-exchange chromatography . This enzyme catalyses the cleavage of the thioether linkage in cysteine conjugates of the following S-alkyl- or S-aryl-linked compounds: cysteine conjugate of propachlor (2-S-cysteinyl-N-isopropylacetanilide); 1,2-dihydro-1-hydroxy-2-S-cysteinylnaphthalene and S-(2-benzothiazolyl)cysteine . 2-Mercapto-N-isopropylacetanilide, pyruvic acid and ammonia were produced from the beta-lyase cleavage of the cysteine conjugate of propachlor in equimolar ratios . The apparent Km values for the cysteine conjugate of propachlor and S-(benzothiazolyl)cysteine were 1.1 and 1.0 mM, respectively . Pyridoxal phosphate was required for enzymic activity . Ammonium ion activated enzymic activity, while hydroxylamine completely inhibited the enzyme . Dithiothreitol and bovine serum albumin had no effect on enzymic activity.

Z Naturforsch {C}, 1983 Nov-Dec, 38(11-12), 968 - 71
Molecular properties of high potential iron sulfur protein of Chromatium warmingii; Wermter U et al.; High potential iron sulfur protein (HIPIP) of the purple sulfur bacterium Chromatium warmingii was purified to homogeneity by ion exchange chromatography, gel filtration and ammonium sulfate fractionation . The acidic protein was isolated in the reduced form . The best purity index (A280/A388) obtained was 2.52, and 3.8 mumol of the protein was isolated out of 100 g wet cell material . The molecular weights estimated by sodium dodecylsulfate polyacrylamide gel electrophoresis and gel filtration through Sephacryl S-200 were 8900 and 10 500, respectively . The protein has an isoelectric point at pH 3.6 for the reduced form and at pH 3.8 for the oxidized form, and a midpoint redox potential of +355 mV . One mol of HIPIP contains 4 mol nonheme iron and 4 mol acid-labile sulfur.

Z Naturforsch {C}, 1983 Nov-Dec, 38(11-12), 960 - 7
Cytochromes and anaerobic sulfide oxidation in the purple sulfur bacterium Chromatium warmingii; Wermter U et al.; Two soluble acidic c-type cytochromes--c' and c-552--were isolated by ion exchange chromatography, gel filtration and ammonium sulfate fractionation . Cytochrome c' is a high-spin cytochrome with maxima at 399 nm, 490 nm, and 634 nm in the oxidized form and at 550 nm, 425 nm and a characteristic shoulder at 434 nm in the reduced state . The best purity index obtained (A280/A399) was 0.35 . Cytochrome c' is autoxidizable, has a molecular weight of 12000 (estimated by sodium dodecylsulfate electrophoresis), a midpoint redoxpotential of +10 mV and an isoelectric point at pH 4.0 . The reduced cytochrome c' reacts with carbon monoxide . The reaction is reversible . Cytochrome c-552 shows maxima at 552 nm, 523 nm and 417 nm in the reduced form and at 408 nm in the oxidized state . The best purity index obtained (A280/A408) was 0.94 . Cytochrome c-552 has a molecular weight of 30000 and an isoelectric point between pH 4.3 and 5.0 . Chromatium warmingii also contains a membrane-bound cytochrome c-552 . During anaerobic sulfide oxidation, elemental sulfur and sulfate were formed at the same time . When all sulfide was consumed by the cells, the remaining intracellular elemental sulfur was further oxidized to sulfate.

Z Naturforsch {C}, 1983 Nov-Dec, 38(11-12), 933 - 8
Purification and characterization of a dissimilatory nitrite reductase from the phototrophic bacterium Rhodopseudomonas palustris; Preuss M et al.; A dissimilatory nitrite reductase from the facultatively phototrophic bacterium, Rhodopseudomonas palustris strain 1a1 was studied . A basic level of the enzyme (10-50 mU/mg protein) was measured in dark, aerated and anaerobic, photosynthetic cultures . A marked derepression of enzyme synthesis occurred under conditions of oxygen limitation (200-300 mU/mg protein) . The addition of nitrite (or nitrate) to the culture medium had only a slight effect on the maximal nitrite reductase titer of cells . The enzyme was purified from photosynthetically grown cells by precipitation with ammonium sulfate, gel filtration through Sepharose 6B and repeated chromatography on DE 52-cellulose . As estimated by gel filtration, the nitrite reductase had a molecular weight of about 120 000 +/- 12 000 and yielded only one band (mol . wt . of about 68 000 +/- 7000) in SDS-gel electrophoresis . The isoelectric point of the enzyme was at pH 5.1 . Nitric oxide (NO) was identified as the reaction product of nitrite reduction . The enzyme also exhibited cytochrome c-oxidase activity and was active with chemically reduced viologen dyes, FMN and cytochrome c as electron donors . Highly purified nitrite reductase preparations contained 10 mol% of a c-type cytochrome . Trace metal analyses indicated the presence of Cu in the enzyme . Consistent with the detection of Cu was the finding that the Cu-chelator, diethyldithiocarbamate, strongly inhibited the nitrite reductase.

Eur J Cell Biol, 1983 Nov, 32(1), 86 - 91
Conjugation and meiosis of Paramecium caudatum infected with the micronucleus-specific bacterium Holospora elegans; Gortz HD et al.; Cells of two complementary mating types of Paramecium caudatum, syngen 3, are infected with the micronucleus-specific bacterium Holospora elegans . Cells with bacteria in their micronuclei show the mating reaction with agglutination and pair formation . All the stages of meiosis in this species are observed and pronuclei are formed . During the pregamic divisions the bacteria are distributed to the division products, but many of the bacteria remain within the separation spindles, later being released into the medium . Therefore, the pronuclei contain only a few or no bacteria . In a test of the viability of exconjugant clones CNR-mutant (a behavioral mutant) and wild type cells, both infected with H . elegans, are crossed . The survival of exconjugants is very low (10.6% compared to 57.3% in the control) . After conjugation only parental types are found indicating the occurrence of macronuclear regeneration after conjugation . The same result is obtained with cells which had contained bacteria but were cured by means of antibiotics . It is concluded that infected micronuclei have become genetically defective and did not give rise of new functional macronuclei . Therefore, H . elegans-bearing paramecia are genetically dead, which shows the parasitic nature of the bacterium H . elegans.

J Biochem (Tokyo), 1983 Nov, 94(5), 1569 - 78
Action of levan fructotransferase of Arthrobacter ureafaciens on levanoligosaccharides; Tanaka K et al.; Levan fructotransferase of the bacterium Arthrobacter ureafaciens, which produces di-D-fructose 2,6':6,2' dianhydride (difructose anhydride IV) from levan by an intramolecular transfructosylation reaction, was purified to give a single protein band of pI 4.5-4.7 on isoelectric focusing . It had a molecular weight of 128,000 on gel-filtration on Sephadex G-200 and 60,000 on SDS-polyacrylamide disc gel-electrophoresis, suggesting that the enzyme is composed of two identical subunits . The shortest levanoligosaccharide chain required for the difructose anhydride IV formation was determined to be tetraose . TLC of the enzymic digest of a modified levanhexaose derived from levanhexaose by the reduction of the reducing end to an alditol residue with sodium borohydride gave the difructose anhydride IV spot, suggesting that the enzyme attacks the modified levanhexaose molecule from the direction of the non-reducing fructose end . The enzymic digests of levantetraose, -pentaose, and -hexaose as the substrate gave, in addition to the difructose anhydride IV spot, spots of oligofructans of lower mobility than the original substrate on TLC . From the digest of levantetraose, a hexaoligofructan and a smaller amount of a pentaoligofructan but no fructose were separated, indicating enzymic intermolecular levanbiosyl and fructosyl transfer reactions.

J Bacteriol, 1983 Nov, 156(2), 600 - 10
Separation and distribution of thiosulfate-oxidizing enzyme, tetrathionate reductase, and thiosulfate reductase in extracts of marine heterotroph strain 16B; Whited GM et al.; Thiosulfate-oxidizing enzyme (TSO), tetrathionate reductase (TTR), and thiosulfate reductase (TSR) were demonstrated in cell-free extracts of the marine heterotrophic thiosulfate-oxidizing bacterium strain 16B . Extracts prepared from cells cultured aerobically in the absence of thiosulfate or tetrathionate exhibited constitutive TSO and TTR activity which resided in the soluble fraction of ultracentrifuged crude extracts . Constitutive TSO and TTR cochromatographed on DEAE-Sephadex A-50, Cellex D, Sephadex G-150, and orange A dye-ligand affinity gels . Extracts prepared from cells cultured anaerobically with tetrathionate or aerobically with thiosulfate followed by oxygen deprivation showed an 11- to 30-fold increase in TTR activity, with no increase in TSO activity . The inducible TTR resided in both the ultracentrifuge pellet and supernatant fractions and was readily separated from constitutive TSO and TTR in the latter by DEAE-Sephadex chromatography . Inducible TTR exhibited TSR activity, which was also located in both membrane and soluble extract fractions and which cochromatographed with inducible TTR . The results indicate that constitutive TSO and TTR in marine heterotroph 16B represent reverse activities of the same enzyme whose major physiological function is thiosulfate oxidation . Evidence is also presented which suggests a possible association of inducible TTR and TSR in strain 16B.

J Biochem (Tokyo), 1983 Nov, 94(5), 1587 - 93
Inhibitory effect of N,N'-dicyclohexylcarbodiimide (DCCD) on the electron transfer involving cytochrome b-c2 oxidoreductase in Rhodopseudomonas sphaeroides; Takamiya K; N,N'-Dicyclohexylcarbodiimide (DCCD) inhibited dark re-reduction of cytochrome c2 and reduction of b-type cytochrome, both of which are closely associated with electron transfer involving a cytochrome b-c2 oxidoreductase, after a single-turnover flash excitation in the chromatophore membranes from a photosynthetic bacterium, Rhodopseudomonas sphaeroides . Rapid proton uptakes (HI+, HII+) and the formation of the membrane potential registered by carotenoid bandshift phase III were also inhibited by DCCD . The electron transfer was inhibited in the presence of either valinomycin or carbonylcyanide-m-chlorophenylhydrazone (CCCP) . These results indicated that DCCD inhibited the electron transfer involving the cytochrome b-c2 oxidoreductase in the bacterium . The inhibition was irreversible . A hydrophilic carbodiimide, 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide (EDAC), did not affect the above-mentioned reactions . Thus, DCCD may interact with the hydrophobic region(s) in the chromatophore membranes from photosynthetic bacteria resulting in the inhibition(s) of the photosynthetic cyclic electron transfer.

FEBS Lett, 1983 Oct 17, 162(2), 420 - 2
Evidence for two distinct pyruvate kinase genes in Escherichia coli K-12; Garrido-Pertierra A et al.; A strain of Escherichia coli K-12 defective in pyruvate kinase F has been produced . The existence of this mutant, in conjunction with earlier results, strongly suggests that the two pyruvate kinases in this bacterium are distinct forms and not interconvertible . Either form of pyruvate kinase appeared to be equally effective in the glycolytic conversion of phosphoenolpyruvate to pyruvate . Genes specifying pyruvate kinase A and pyruvate kinase F were present on the small F-prime F506 and the locus for pyruvate kinase F was found to be at minute 36.5 on the E . coli genetic map.

Biokhimiia, 1983 Oct, 48(10), 1726 - 32
{Coupling between 3-ketosteroid-delta'-dehydrogenase and the respiratory chain in the bacterium Arthrobacter globiformis}; Medentsev AG et al.; Intact bacterial cells and their cytoplasmic membranes obtained by ultrasonic desintegration are able to induce dehydration of hydrocortisone to prednisolone that is coupled with O2 uptake . This reaction is inhibited by cyanide and 2-n-nonyl-4-hydroxyquinoline-N-oxide (HOQNO) . Oxidation of hydrocortisone results in cytochrome reduction both in intact cells and in cytoplasmic membranes . Aerobic dehydration of hydrocortisone is linked with transmembrane potential generation . The data obtained suggest that the electron translocation from 3-ketosteroid-delta'-dehydrogenase to O2 occurs via the respiratory chain . The enzyme donates reduced equivalents directly to the respiratory chain, presumably at the level of menaquinone.

J Exp Med, 1983 Oct 1, 158(4), 1319 - 31
Formation of a novel phagosome by the Legionnaires' disease bacterium (Legionella pneumophila) in human monocytes; Horwitz MA; Previous studies have shown that L . pneumophila multiplies intracellularly in human monocytes and alveolar macrophages within a membrane-bound cytoplasmic vacuole studded with ribosomes . In this paper, the formation of this novel vacuole is examined . After entry into monocytes, L . pneumophila resides in a membrane-bound vacuole . During the first hour after entry, vacuoles containing L . pneumophila are found surrounded by smooth vesicles fusing with or budding off from the vacuolar membrane and by mitochondria closely apposed to the vacuolar membrane . By 4 h, vacuoles are found less frequently surrounded by these cytoplasmic organelles, but now ribosomes and rough vesicles are found gathered about the vacuole . By 8 h, the ribosome-lined vacuole has formed . Erythromycin, at concentrations that completely inhibit the intracellular multiplication of L . pneumophila, has no effect on vacuole formation . Formalin-killed L . pneumophila also reside in a membrane-bound vacuole after entry into monocytes . In contrast to the situation with live L . pneumophila, cytoplasmic organelles are not found surrounding vacuoles containing formalin-killed L . pneumophila at any time after entry . Formalin-killed bacteria are rapidly digested, and by 4 h, few remain intact . The L . pneumophila-containing vacuole has certain features in common with other intracellular organisms that inhibit phagosome-lysosome fusion; these organisms may share a common mechanism for vacuole formation and inhibition of phagosome-lysosome fusion.

J Cell Biol, 1983 Oct, 97(4), 1098 - 106
Distribution of sterol-specific complexes in a continually shearing region of a plasma membrane and at procaryotic-eucaryotic cell junctions; Tamm SL et al.; A narrow zone of plasma membrane between the head and body of a protozoan from termites undergoes continual in-plane shear because the head rotates continuously in the same direction relative to the cell body (Tamm, S.L., and S . Tamm, 1974, Proc . Natl . Acad . Sci . USA 71:4589-4593) . Using filipin and digitonin as cytochemical probes for cholesterol and related 3-beta-hydroxysterols, we found a high level of sterol-specific complexes, visible as membrane lesions in thin sections, in both shearing and nonshearing regions of the membrane, indicating no difference in sterol content . This confirmed previous observations that any region of the fluid membrane can undergo shear, but that this occurs only at certain locations due to cell geometry and proximity to rotating cytoskeletal structures . Filipin and digitonin did not disrupt the plasma membrane at the junctions with ectosymbiotic rod and fusiform bacteria (i.e., membrane pockets and ridges) . However, pepsin degradation of dense material coating the junctional membranes resulted in a positive response of these regions to filipin . Fluorescence microscopy revealed a bright halo around each rod bacterium, due to filipin-sterol binding in the sides of the membrane pockets, but no fluorescence at the bottom of the pockets; the same fluorescence pattern was found in pepsin-treated cells despite the presence of sterols throughout the pocket membrane, as shown by electron microscopy . These findings indicate that (a) regional constraints may restrict the ability of filipin to interact with sterols or form visible membrane lesions, and (b) a negative response to filipin, assayed by either electron or fluorescence microscopy, is not sufficient to demonstrate low membrane sterol concentration, particularly in membrane domains characterized by closely associated proteins.

J Cell Biol, 1983 Oct, 97(4), 1266 - 70
Two-dimensional crystals formed from photosynthetic reaction centers; Miller KR et al.; Photosynthetic reaction centers from the bacterium Rhodopseudomonas viridis were prepared after detergent solubilization of photosynthetic membranes . The purified reaction centers, in agreement with reports from other laboratories, contain four distinct polypeptides ranging in molecular weight from 28,000 to 41,000 . When the detergent was gradually removed by dialysis under appropriate conditions, large two-dimensional sheets of reaction centers were formed, suitable for analysis by electron microscopy . The crystals were rectangular, and the dimensions of a single unit cell were 121 X 129 A . Each unit cell contained four distinct subunits, each with approximate dimensions of 45 X 60 A . The thickness of the sheet was 60 A . Preliminary studies of the sheets with negative staining indicated that the sheets show a high degree of order: as many as six orders are visible in transforms of the images . Because of the fact that in R . viridis the native membrane from which these reaction centers were purified also displays a crystal-like structure, comparative studies between a membrane and one of its components, each analyzed by Fourier techniques, are now possible.

J Bacteriol, 1983 Oct, 156(1), 434 - 6
Transfer of plasmid RP1 into chemolithotrophic Thiobacillus neapolitanus; Kulpa CF et al.; RP1, a broad-host-range incompatibility group P1 plasmid specifying multiple drug resistances, has been transferred into the chemolithotrophic bacterium Thiobacillus neapolitanus . The ability of T . neapolitanus to receive, express, and transmit RP1-encoded antibiotic resistances was examined . The data show that this obligate chemolithotroph can accept, replicate, and express heterologous plasmid DNA from a heterotrophic bacterium.

J Bacteriol, 1983 Oct, 156(1), 348 - 53
Localization of the major dehydrogenases in two methylotrophs by radiochemical labeling; Kasprzak AA et al.; The localization of prominent proteins in intact cells of two methylotrophic bacteria, Hyphomicrobium sp . strain X and bacterium W3A1, was investigated by radiochemical labeling with {14C}isethionyl acetimidate . In bacterium W3A1, trimethylamine dehydrogenase was not labeled by the reagent and is, therefore, an intracellular protein, whereas the periplasmic location of the methylamine and methanol dehydrogenases was evidenced by being readily labeled in intact cells . Similarly, an intracellular location of the trimethylamine and dimethylamine dehydrogenases in Hyphomicrobium sp . strain X was indicated, whereas methanol dehydrogenase was periplasmic.

Zentralbl Bakteriol Mikrobiol Hyg {A}, 1983 Sep, 255(2-3), 294 - 8
Establishment of hybridoma cell lines secreting anti-Legionella pneumophila serogroup 1 monoclonal antibodies with immunodiagnostic potential; Sethi KK et al.; Three independent hybridoma cell lines (F4/CB5/K18, F4/CB5/K104, F4/JD3.8/K101) producing monoclonal antibodies that reacted specifically against cell surface molecule(s) of Legionella pneumophila serogroup 1 have been established . These monoclonal antibodies belong to IgM class and are capable of agglutinating exquisitely serogroup 1 organisms . These hybridoma-derived monoclonal antibodies can be used for the preparation of standardized immunodiagnostic reagents for detection and rapid identification of Legionnaire's disease bacterium in clinical laboratories and will also enable purification and subsequent characterization of the serogroup 1 specific molecule(s) of L . pneumophila.

Rev Infect Dis, 1983 Sep-Oct, 5 Suppl 4, S647 - 58
Models for studying the role of bacterial attachment in virulence and pathogenesis; Freter R et al.; Simple in vitro tests for bacterial adhesion can indeed identify the various adhesive mechanisms of bacteria on an immunologic, physiochemical, biochemical, and genetic basis . Difficulties in interpretation arise, however, when attempts are made to relate the presence of a given adhesion to the colonizing ability or virulence of a bacterium . The reasons for this confusion are threefold: (1) there is more than one basic mechanism by which bacteria may associate with mucosae; (2) numerous intervening reactions in the mucosal microenvironment modify the various steps leading to association; and (3) mucosal association may sometimes be detrimental to a bacterium . Bacterial association with the mucosa, therefore, is determined by the final equilibrium established as a consequence of various synergistic and antagonistic reactions . An understanding of such a complex, interdependent system of reactions cannot be gained solely by studying each of its component parts in isolation . More complex models, such as those developed in experimental animals, are therefore required, and the relationship between adhesion and colonization must be explored within the conceptual framework employed by ecologists.

Infect Immun, 1983 Sep, 41(3), 1132 - 7
Cellular immunity to Legionella pneumophila in guinea pigs assessed by direct and indirect migration inhibition reactions in vitro; Friedman H et al.; Spleen cell cultures from guinea pigs given legionella pneumophila vaccine in complete Freund adjuvant or as a sublethal infection were inhibited in their migration activity in vitro when incubated with specific antigen . Both direct and indirect migration inhibition assays revealed sensitization of the guinea pigs to the bacterium, with demonstrable reactivity 25 to 40 days or more after sensitization . No consistent reactions occurred when the guinea pigs were given the killed Legionella vaccine in incomplete Freund adjuvant in saline . However, spleen cells from guinea pigs injected with sublethal doses of the Legionella vaccine 3 to 4 weeks earlier showed positive migration inhibition factor reactivity . Cutaneous hypersensitivity and lymphocyte blastogenic responsiveness in vitro also developed in guinea pigs sensitized with killed Legionella vaccine in complete adjuvant or given a sublethal infection with the bacterium . These results indicate that in vitro assays for migration inhibitory activity may be utilized to monitor the development of the sensitization of guinea pigs to L . pneumophila, and such reactions correlate with skin reactivity and in vitro lymphocyte blastogenic responses.

Nature, 1983 Aug 4-10, 304(5925), 466 - 8
Inducible repair of oxidative DNA damage in Escherichia coli; Demple B et al.; Hydrogen peroxide is lethal to many cell types, including the bacterium Escherichia coli . Peroxides yield transient radical species that can damage DNA and cause mutations . Such partially reduced oxygen species are occasionally released during cellular respiration and are generated by lethal and mutagenic ionizing radiation . Because cells live in an environment where the threat of oxidative DNA damage is continual, cellular mechanisms may have evolved to avoid and repair this damage . Enzymes are known which evidently perform these functions . We report here that resistance to hydrogen peroxide toxicity can be induced in E . coli, that this novel induction is specific and occurs, in part, at the level of DNA repair.

J Bacteriol, 1983 Aug, 155(2), 634 - 42
In vivo 31P and 13C nuclear magnetic resonance studies of acetate metabolism in Chromatium vinosum; Nicolay K et al.; 31P and 13C nuclear magnetic resonance (NMR) experiments were performed on suspensions of the phototrophic bacterium Chromatium vinosum incubated anaerobically in the dark . 31P NMR spectra revealed that during prolonged dark incubation high ATP levels are maintained . This phenomenon was independent of the presence of the energy reserves polyglucose and polyphosphate . 13C NMR experiments revealed that the amino acids glutamate, aspartate, and alanine are the major products of acetate incorporation in the dark . Apart from these amino acids, poly-beta-hydroxybutyrate was also formed . Acetate metabolism was markedly stimulated by the presence of polyglucose . The specific 13C activity of glutamate C-2 was approximately 50% that of glutamate C-4 . The idea is discussed that this difference is the consequence of the maintenance of redox balance during entry of acetate into cell metabolism.

J Immunol, 1983 Aug, 131(2), 997 - 9
Involvement of lipopolysaccharide in the pathogenicity of Treponema hyodysenteriae; Nuessen ME et al.; Treponema hyodysenteriae, the etiologic agent of swine dysentery, caused gross and microscopic lesions in the large intestines of C3HeB/FeJ mice . No gross lesions were observed in the intestines of the closely related, but lipopolysaccharide-resistant, C3H/HeJ strain of mice, and microscopic lesions were mild, if present at all . In the presence of actinomycin D, 1 mg of T . hyodysenteriae lipopolysaccharide (LPS) was lethal for C3HeB/FeJ but not for C3H/HeJ mice . Also, the treponemal LPS was chemotactic for macrophages from C3H/HeJ mice but not for macrophages from C3HeB/FeJ mice . The difference between the two mouse strains in lesion development may be due to the nondestructive nature of LPS in C3H/HeJ mice, which suggests that the treponemal LPS is involved in the pathogenicity of T . hyodysenteriae . T . hyodysenteriae may prove to be a useful bacterium in the study of LPS-resistant C3H/HeJ mice, because resistance to the treponemal LPS and to the treponeme itself appear to correlate.

Arch Biochem Biophys, 1983 Aug, 225(1), 86 - 94
L-aspartate transport in the photosynthetic bacterium Chromatium vinosum; Cobb AD et al.; The photosynthetic purple sulfur bacterium Chromatium vinosum appears to contain two active transport systems for L-aspartate . The higher affinity system (S0.5 = 60 microM) appears to be an electrogenic aspartate/H+ symport and the lower affinity system (S0.5 = 220 microM) appears to involve an aspartate/Na+ symport . In addition to a possible role in providing the driving force for aspartate uptake, transmembrane Na+ gradients may also have allosteric effects on aspartate transport in C . vinosum.

J Mol Biol, 1983 Jul 15, 167(4), 823 - 48
Three-dimensional arrangement of the cell wall protein of Sulfolobus acidocaldarius; Deatherage JF et al.; The three-dimensional structure of the S-layer that surrounds the bacterium Sulfolobus acidocaldarius is described in detail . Pieces of the S-layer, which are two-dimensional crystals with p6 symmetry, have been studied by crystallographic analysis of electron micrographs of tilted specimens . In the density map, each asymmetric unit appears to consist of several domains connected by strong hinges . On the basis of the ragged appearance of the structure at torn edges, we now suggest that the single species of polypeptide is in a highly extended conformation, with much overlap between different molecules, and show how such molecules might be weaved together to produce the morphological domains . We show that the closed surface lattice of the intact cell wall contains 5-fold and 7-fold vertices and show how the subunit structure appears to be well suited to form 5-fold and 7-fold symmetric rings at these points in place of the 6-fold rings of the hexagonal lattice.

Arch Biochem Biophys, 1983 Jul 1, 224(1), 152 - 60
Biosynthetic mechanism of ribulose-1,5-bisphosphate carboxylase in the purple photosynthetic bacterium, Chromatium vinosum . III . Absence of extrachromosomal DNA; Kobayashi H et al.; Inducible formation of ribulose-1,5-bisphosphate (RuBP) carboxylase in the cells of Chromatium vinosum under autotrophic conditions was not affected by six different inhibitors of DNA synthesis . Photosynthetic CO2 fixation and RuBP carboxylase activities were not influenced by seven reagents known to eliminate plasmids . Plasmids were not detectable by agarose gel electrophoresis employing either the cleared lysate or alkaline sodium dodecyl sulfate method, nor were they detected by ethidium bromide-CsCl density gradient centrifugation . Overall experimental results tend to indicate that plasmids are absent in the Chromatium cells and that the induction of RuBP carboxylase is presumably not regulated in the DNA replication process.

Biokhimiia, 1983 Jul, 48(7), 1181 - 7
{High potential iron-sulfur protein from Thiocapsa roseopersicina}; Zorin NA et al.; A high potential protein (HiPIP) containing a {4Fe-4S} cluster was obtained in a homogeneous state from the purple sulfur bacterium T . roseopersicina strain BBS . The EPR and absorption spectra are specific for this type of proteins . In the absorption spectrum the A283/A390 ratio equals to 2.25; Mr = 10 000, pI is 4.08, E0' = +328 mV . The reduced form of HiPIP was found to be more stable upon storage; T 1/2 is 40 min at 80 degrees C . HiPIP can be reduced by ascorbate, cysteine, 2-mercaptoethanol and sulfide as well as by formate, H2 and NADPH in the presence of corresponding enzymes . Chromatophores oxidize HiPIP in the light . This suggests that the latter takes part in the photosynthetic electron transfer chain of T . roseopersicina.

Appl Environ Microbiol, 1983 Jul, 46(1), 120 - 7
Metabolism of T-2 toxin in Curtobacterium sp . strain 114-2; Ueno Y et al.; The metabolic pathway of T-2 toxin in Curtobacterium sp . strain 114, one of the T-2 toxin-assimilating soil bacteria, was investigated by thin-layer and gas-liquid chromatographic analyses . T-2 toxin added to the basal medium as a single carbon and energy source was biotransformed into HT-2 toxin and an unknown metabolite . Infrared, mass spectrum, proton magnetic resonance, and other physico-chemical analyses identified this new metabolite as T-2 triol . T-2 toxin was first deacetylated by the bacterium into HT-2 toxin, and this metabolite was then biotransformed into T-2 triol without formation of neosolaniol and T-2 tetraol . No trichothecenes remained in the culture medium after prolonged culture . Some properties of T-2 toxin-hydrolyzing enzymes were observed with whole cells, the cell-free soluble fraction, and the culture filtrate . Besides T-2 toxin, trichothecenes such as diacetoxyscirpenol, neosolaniol, nivalenol, and fusarenon-X were also assimilated by this bacterium.

Mikrobiologiia, 1983 Jul-Aug, 52(4), 533 - 7
{Growth of Seliberia carboxydohydrogena carboxy bacteria with an altered composition of the gas mixture}; Volova TG et al.; The growth and gas exchange of Seliberia carboxydohydrogena Z-1062 were studied in the regime of turbidostat when the conditions of gaseous nutrition were changed: a decrease in hydrogen concentration and an increase in carbon monoxide concentration, growth on two carbon sources (CO+CO2) and on two energy sources (H2+CO) . The inhibition of the bacterial growth by CO was expressed in a decrease of the specific growth rate and in the reduced effectiveness of using a gaseous substrate . When the concentration of carbon monoxide was elevated from 0 to 40% and that of hydrogen was reduced from 80 to 40%, the specific growth rate of the cells was decreased from 0.4 to 0.04 h-1; here, the economic coefficient in terms of hydrogen fell from 3.6 to 0.62 g/g . The CO-oxidizing system of the bacterium was shown to be resistant . The rate of CO oxidation by the culture was from 0.6 to 0.8 L/h per 1 g of the synthesized biomass at the following concentration of gases in the medium (%); H2, 80-40; CO2, 5; O2, 15; CO, 10-40 . The rate of CO oxidation by the culture rose when hydrogen concentration was decreased and CO concentration was increased.

Ann Microbiol (Paris), 1983 Jul-Aug, 134B(1), 151 - 8
Molecular-organization and biosynthesis of pigment-protein complexes of Rhodopseudomonas capsulata; Drews G et al.; The photosynthetic apparatus of the facultative phototrophic bacterium Rhodopseudomonas capsulata contains three bacteriochlorophyll-carotenoid-protein complexes: the reaction center and the light-harvesting (LH) antenna complexes LHI (B870) and LHII (B800--850) . In contrast to green anoxygenic phototrophic bacteria and the oxygenic cyanobacteria, the light-harvesting complexes of Rhodospirillaceae and Chromatiaceae are integral membrane particles . Variations in light fluxes induce membrane differentiation mainly expressed as variations in the size of the photosynthetic unit and in the area of intracytoplasmic membrane per cell . The B800--850 complex is the variable part of the photosynthetic apparatus . Synthesis of bacteriochlorophyll and of the polypeptides of the pigment complexes was found to be strongly coordinated . The synthesis of these polypeptides was followed immediately by the assembly of the complexes in the membrane . Bacteriochlorophyll or a signal substance triggered by bacteriochlorophyll synthesis regulated the synthesis of these polypeptides at the level of translation . The pigment-binding subunits of the B800--850 complex form oligomeric structures which interact with subunit H of the reaction center . A model of the topographical relationships of the pigment complexes is discussed.

Am Rev Respir Dis, 1983 Jul, 128(1), 98 - 103
The use of quantitative cultures and antibody coating of bacteria to diagnose bacterial pneumonia by fiberoptic bronchoscopy; Winterbauer RH et al.; This study uses quantitative cultures and immunofluorescent demonstration of antibody-coated bacteria to differentiate colonizing from infecting bacteria in lower respiratory secretions obtained by fiberoptic bronchoscopy . The fiberoptic bronchoscope was passed transnasally without the use of a nasotracheal tube, and a single-sheath cytology brush dipped in lower respiratory secretions served as inoculum for quantitative cultures . Secretions were also collected by aspiration through the bronchoscope side channel for fluorescent examination . None of 60 control patients had greater than 4,000 colony-forming units (CFU) per brush of a single bacterium on quantitative culture . In contrast, more than 4,000 CFU per brush were isolated from 29 of 33 episodes of clinically defined lower respiratory infection (p less than 0.001) . Only 1 of 60 control patients had antibody-coated bacteria in their lower respiratory secretions, but antibody coating was demonstrated in association with 24 of 33 episodes of infection (p less than 0.001).

J Bacteriol, 1983 Jul, 155(1), 107 - 12
Nitrogen fixation and ammonia switch-off in the photosynthetic bacterium Rhodopseudomonas viridis; Howard KS et al.; Rhodopseudomonas viridis ATCC 19567 grows by means of nitrogen fixation in yeast extract-N2 or nitrogen-free medium when sparged with 5% CO2 and 95% N2 in the light at 30 degrees C . Acetylene reduction assays for nitrogenase activity revealed an initially high level of activity during early-logarithmic growth phase, a lower plateau during mid- to late-logarithmic phase, and a dramatic reduction of activity at the beginning of the stationary phase . When viewed by electron microscopy, nitrogen-fixing R . viridis cells appeared to be morphologically and ultrastructurally similar to cells grown on nitrogen-rich media . Whole cells prepared under reducing conditions in the dark for electron spin resonance spectroscopy yielded g4.26 and g3.66 signals characteristic of the molybdenum-iron protein of nitrogenase . During growth on N2 in the absence of fixed-nitrogen sources, the nitrogenase activity of R . viridis measured by acetylene reduction stopped rapidly in response to the addition of NH4Cl as has been observed in other Rhodospirillaceae . However, unlike the nitrogenase of Rhodopseudomonas palustris or Rhodospirillum rubrum, which recover from this treatment within 40 min, the nitrogenase activity of R . viridis was not detectable for nearly 4 h.

J Bacteriol, 1983 Jul, 155(1), 180 - 5
The wild-type gene for glutamine synthetase restores ammonia control of nitrogen fixation to Gln- (glnA) mutants of Rhodopseudomonas capsulata; Scolnik PA et al.; The wild-type glnA gene, coding for glutamine synthetase, was cloned from the photosynthetic bacterium Rhodopseudomonas capsulata by using a cosmid library to complement the Gln- phenotype of an Escherichia coli glnA deletion strain . The original cosmid plasmid contained 37 kilobase pairs (kbp) of R . capsulata DNA, of which only 2 kbp was necessary for Gln complementation in E . coli . A plasmid containing this 2-kbp insert was mobilized into G29, a Gln- mutant of R . capsulata which is also unable to repress nitrogenase in ammonia-containing media (Nifc phenotype) . The 2-kbp fragment restored glutamine-independent growth and ammonia repression of nitrogenase, indicating that in R . capsulata, production of the signal for nitrogen repression of nif depends on the activity of the glnA gene . Repression of nitrogenase was shown, by hybridization of RNA to cloned nif DNA, to occur at the level of transcription in the wild-type and the complemented G29 strains.

Endocrinology, 1983 Jul, 113(1), 209 - 15
Pertussis toxin blocks the somatostatin-induced inhibition of growth hormone release and adenosine 3',5'-monophosphate accumulation; Cronin MJ et al.; A protein toxin synthesized by the bacterium Bordetella pertussis has the unique property of blocking a number of receptor-mediated inhibitory systems which are linked to adenylate cyclase . We found that pertussis toxin (PT) eliminates the ability of somatostatin to reduce both basal and GH-releasing factor-stimulated GH release in primary cultures of rat pituitary cells . Furthermore, the ability of somatostatin to reduce GH-releasing factor-induced cAMP accumulation in the cells is significantly attenuated after PT treatment . The PT effect, which is dose dependent and prevented by pretreatment with anti-PT antibodies, represents an alteration in somatostatin efficacy rather than potency . The modification of somatostatin responsiveness persists for at least 5 days after toxin removal . The PT actions on the somatotroph are similar to the effects on other eukaryotic cell types . The combination of available data indicates that the toxin acts on a highly conserved component(s) that is obligatory for transducing the inhibitory hormone message into the cell.

J Biol Chem, 1983 Jun 25, 258(12), 7276 - 9
A new opine derived from nopaline; Hall LM et al.; Nopaline (N-{4-{(aminoiminomethyl)amino-}-1S-carboxybutyl}-2R-aminopentanedioic acid and isonopaline (N-{4-{(aminoiminomethyl)amino-1S-carboxybutyl}- 2S-aminopentanedioic acid) have been synthesized and separated by crystallization . In addition, a derivative of each of these compounds that forms spontaneously from the parent compounds under the usual crystallization conditions was isolated and characterized . The chemical properties, elemental analysis, 1H-NMR spectrum, and electrophoretic behavior of the derivative from nopaline are consistent with N-{4-{ (aminoiminomethyl)amino}-1S-carboxybutyl}-2-pyrrolidone-5R-carboxylic acid, also called pyronopaline . The presence of pyronopaline in crown gall tumor tissue and the catabolism of it by the bacterium A . tumefaciens establish it as a new opine.

Nature, 1983 Jun 16-22, 303(5918), 633 - 5
Transposable elements as mutator genes in evolution; Chao L et al.; Strains of the bacterium Escherichia coli harbouring genes that increase mutation rates are known to have an evolutionary advantage in chemostat competition over otherwise isogeneic strains with lower mutation rates . This advantage is frequency-dependent, the mutator strain being favoured only above a starting ratio of approximately 5 x 10(-5), and it results from the fact that the necessary beneficial mutations cannot be generated in a mutator population below a certain size . Here we consider the possibility that the mutagenic properties of transposable elements confer an advantage in the same manner as mutator genes . A previous report has shown that the transposon Tn5 increases the fitness of E . coli in chemostats, although the reason for this effect has not been established . Our results show that the transposon Tn10 also confers an advantage in chemostats . In addition, we find that (1) this advantage, like that associated with mutator genes, is frequency-dependent, (2) whenever the Tn10 strains win, a segment of Tn10, probably its IS10 sequences, has undergone transposition to a new site, (3) the new insertions converge into a site contained within a 3.2 kilobase (kb) PvuII fragment of the genome, and (4) no transpositions are detected when the Tn10 population loses . We conclude that Tn10 confers an advantage by increasing the mutation rate of the host bacterium.

Biochem J, 1983 Jun 1, 211(3), 535 - 41
Identity of the subunits and the stoicheiometry of prosthetic groups in trimethylamine dehydrogenase and dimethylamine dehydrogenase; Kasprzak AA et al.; Trimethylamine dehydrogenases from bacterium W3A1 and Hyphomicrobium X and the dimethylamine dehydrogenase from Hyphomicrobium X were found to contain only one kind of subunit . The millimolar absorption coefficient of a single {4Fe-4S} cluster in trimethylamine dehydrogenase from bacterium W3A1 was estimated to be 14.8 mM-1 . cm-1 at 443 nm . From this value a 1:1 stoicheiometry of the prosthetic groups, 6-S-cysteinyl-FMN and the {4Fe-4S} cluster, was established . Millimolar absorption coefficients of the three enzymes were in the range 49.4-58.7 mM-1 . cm-1 at approx . 440 nm . This range of values is consistent with the presence of two {4Fe-4S} clusters and two flavin residues, for which the millimolar absorption coefficient had earlier been found to be 12.3 mM-1 . cm-1 at 437 nm . The N-terminal amino acid was alanine in each of the three enzymes . Sequence analysis of the first 15 residues from the N-terminus of dimethylamine dehydrogenase indicated a single unique sequence . Two identical subunits, each containing covalently bound 6-S-cysteinyl-FMN and a {4Fe-4S} cluster, in each of the enzymes are therefore indicated.

Arch Microbiol, 1983 Jun, 134(3), 212 - 6
Lipopolysaccharides of two strains of the phototrophic bacterium Rhodopseudomonas capsulata; Omar AS et al.; The lipopolysaccharides of Rhodopseudomonas capsulata strains St . Louis (ATCC 23782) and Sp 11 both contain L-acofriose, rhamnose, glucose and glucosamine as the main sugar constituents . 2-Keto-3-deoxyoctonate and neuraminic acid were tentatively identified . The fatty acid spectrum found with both strains comprises 3-OH-C10 and C12:1 (ester-linked) and 3-oxo-C14 (amide-linked) . Isolated lipid A from strain Sp 11 contains glucosamine, glucosamine-phosphate and the total of the fatty acids of the lipopolysaccharide . Methylation analysis of the degraded polysaccharide of this lipopolysaccharide shows L-acofriose in both terminal and 1 leads to 2 chain-linked positions in a 1:4 molar ratio . Rhamnose is exclusively chain-linked (1 leads to 2), glucose is both terminally and chain-linked (1 leads to 6) in a 1:1 molar ratio . The serological activity of the lipopolysaccharide of both the R . capsulata strains is low in antisera against living or heat-killed cells when tested by passive hemagglutination, Ouchterlony immunoprecipitation or gel-immunoelectrophoresis . No crossreaction was observed among the lipopolysaccharides of R . capsulata strains St . Louis, Sp 11 and 37b4 in immunoprecipitation . Lipopolysaccharide of strain Sp 11 was found to lack lethal toxicity in galactosamine-sensitized mice.

Hoppe Seylers Z Physiol Chem, 1983 Jun, 364(6), 647 - 50
Characteristics and amino-acid composition of a c-type cytochrome in electron acceptor function during thiosulfate-linked photoautotrophic growth of Rhodopseudomonas palustris; Schmitt W et al.; The purple bacterium Rhodopseudomonas palustris (Rhodospirillaceae) was grown in the light with thiosulfatee as the only electron source and HCO theta 3/CO2 as carbon requirement . During thiosulfat oxidation, photolithoautotrophically growing cells transferred the electrons enzymatically towards an endogenous, soluble cytochrome of type c . The cytochrome c in electron acceptor function was purified to homogeneity and appeared as a single protein band in a dodecyl sulfate disc gel electrophoresis . Its molecular mass was determined to be about 16000 Da and its pI value 10.0 . The determination of its amino-acid composition revealed a long-chained cytochrome represented by more than 120 amino-acid residues with a characteristic content of lysine and a lack of tryptophan.

J Bacteriol, 1983 Jun, 154(3), 1309 - 14
Cloning and insertional inactivation of the dye (sfrA) gene, mutation of which affects sex factor F expression and dye sensitivity of Escherichia coli K-12; Buxton RS et al.; Deletions of the Escherichia coli K-12 chromosome between trpR and thr render the bacterium sensitive to the dye toluidine blue (Dye-), and if male (Hfr or F'), the strain is sterile (Fex-), failing to donate F' or chromosomal markers and resistant to male-specific phages as a consequence of its inability to elaborate F pili . A 6-kilobase SalI fragment of E . coli chromosomal DNA cloned into the plasmid pBR322 has been shown to complement both the Dye- and Fex- phenotypes . Insertion of the transposon gamma delta (Tn1000) into a specific part of this plasmid invariably results in both the Dye- and Fex- phenotypes, indicating that these phenotypes derive from mutation in a single gene . Complementation tests between such insertions and sfrA4, a previously isolated mutation resulting in a Fex- phenotype and reported to code for a transcriptional control factor for F (L . Beutin, P . A . Manning, M . Achtman, and N . Willetts, J . Bacteriol . 145:840-844, 1981), indicated that dye and sfrA4 were mutations in a single cistron . It is proposed that the dye (sfrA) gene product is necessary not only for efficient transcription of the F factor genes, but also for some component(s) of the bacterial envelope, loss of which results in sensitivity to toluidine blue.

FEBS Lett, 1983 May 8, 155(2), 187 - 91
The terminal respiratory chain of the methylotrophic bacterium Methylophilus methylotrophus; Carver MA et al.; Cytochrome oxidase o has been isolated from the obligately aerobic, methylotrophic bacterium Methylophilus methylotrophus in the form of a cytochrome cL-o complex . The latter is comprised of cytochrome cL (Mr 21 000) and cytochrome o (Mr 29 000) in a 1-2:1 ratio, possibly in association with one or more minor polypeptides; the complex exhibits a high ascorbate-TMPD oxidase activity which is inhibited non-competitively by cyanide (Ki approximately 2 microM) . In contrast, the oxidation of methanol by whole cells is inhibited uncompetitively by cyanide (Ki approximately 4 microM), thus indicating the involvement in methanol oxidation of cytochrome oxidase aa3 rather than o.

J Clin Microbiol, 1983 May, 17(5), 819 - 23
Agar microdroplet assay for delayed hypersensitivity to Legionella pneumophila serogroup 1; Widen R et al.; An agarose microdroplet technique was utilized to assess the cellular immunity of guinea pig lymphoid cells to Legionella pneumophila antigen in vitro . Both direct and indirect migration inhibition procedures were shown to be capable of detecting sensitization of guinea pigs to L . pneumophila antigens . Animals injected with adjuvant alone or unrelated antigens did not yield spleen cells responsive to L . pneumophila, indicating the specificity of the response . Migration inhibition factor induction by Legionella antigen in vitro correlated well with skin test responses in vivo . The positive reaction detected by migration inhibition occurred at times similar to that of skin reactivity but later than that of the earliest serum antibody titers . The assay appears to be useful for monitoring sensitization to Legionella and may be applicable to the study of cell-mediated immunity to this bacterium in infected individuals.

Biokhimiia, 1983 May, 48(5), 811 - 7
{Properties of two forms of ferredoxin from Rhodopseudomonas capsulata}; Iakunin AF et al.; Electrophoretically homogenous preparations of two forms of ferredoxin were isolated from the nitrogen-fixing cells of the purple non-sulphur bacterium Rhodopseudomonas capsulata B10 . The values of Mr for ferredoxins I and II are 12000 and 18000, respectively . Ferredoxin I contains 8 atoms of Fe+2 and 8 atoms of S2-; ferredoxin II--4 atoms of Fe2+ and 4 atoms of S2- per molecule . The ferredoxins differ also in their absorption spectra, stability and catalytic activity during electron transfer to nitrogenase of Rh . capsulata . The reduction of C2H2 and evolution of H2 in the presence of ferredoxin I occurs twice as fast as compared to that in the presence of ferredoxin II . Ferredoxin I synthesis takes place in the nitrogen-fixing cells of Rh . capsulata alone, whereas ferredoxin II formation does not depend on the growth conditions.

J Bacteriol, 1983 May, 154(2), 604 - 11
Correlation between bacteriophage chi adsorption and mode of flagellar rotation of Escherichia coli chemotaxis mutants; Ravid S et al.; We studied the adsorption of phage chi to various behavioral mutants (che mutants) of Escherichia coli having different swimming modes . Bacteriophage chi infects only bacteria with active flagella, and it was therefore of interest to examine whether the mode of swimming has an effect on the susceptibility of the bacteria to the phage . Neither the mode of swimming (smooth swimming or tumbling) nor the direction of flagellar rotation affected the degree of chi adsorption to the bacterial cells . Furthermore, the tumbling frequency, the rotation speed (tethered cells of all of the strains examined had the same average speed of rotation), the time proportion of rotation, and the reversal frequency were not important in determining susceptibility to chi . The only variable that influenced chi adsorption was the fraction of the population whose flagella rotated incessantly . A direct, linear correlation was found between chi adsorption and the fraction of unceasing rotation in each population . It seems, therefore, that an individual bacterium whose flagella pause periodically and briefly during rotation is not susceptible to irreversible adsorption of the phage . Pausing of rotation thus seems to be a new feature of motility that is prevalent especially in che mutants . It is concluded that irreversible chi adsorption can serve as a quantitative assay only for incessant flagellar rotation of E . coli.

Nature, 1983 Apr 14, 302(5909), 630 - 2
Caulobacter flagellin mRNA segregates asymmetrically at cell division; Milhausen M et al.; Molecular processes which promote the spatial localization of subcellular components are fundamental to cell development and differentiation . At various stages in development unequal segregation of molecular information must occur to result in the differentiated characteristics which distinguish cell progeny . Biological attributes of the dimorphic bacterium, Caulobacter crescentus, provide an experimental system permitting examination of the generation of asymmetry at the molecular level . When a Caulobacter cell divides, two different daughter cells are produced--a motile swarmer cell with a polar flagellum and a non-motile cell with a static appendage referred to as a stalk . The two cell types are distinct with respect to surface morphology, developmental potential, protein composition and biosynthetic capabilities . One of the more conspicuous manifestations of asymmetric expression of macromolecules in this system, the flagellum, has been studied extensively . We have cloned the flagellin genes of Caulobacter and report here the use of these sequences as probes to demonstrate that (1) the level of flagellin mRNA is regulated during the cell cycle in a pattern coincident with flagellum polypeptide synthesis and (2) flagellin mRNA synthesized before cell division is segregated with progeny swarmer cells . This provides molecular evidence of specific partitioning of an mRNA at the time of cell division.

J Biol Chem, 1983 Apr 10, 258(7), 4419 - 23
Solubilization of the UDP-glucose:1,4-beta-D-glucan 4-beta-D-glucosyltransferase (cellulose synthase) from Acetobacter xylinum . A comparison of regulatory properties with those of the membrane-bound form of the enzyme; Aloni Y et al.; A procedure has been developed for the effective solubilization of UDP-glucose:1,4-beta-D-glucan 4-beta-D-glucosyltransferase (cellulose synthase) by treatment of membranes from the bacterium Acetobacter xylinum with digitonin . Low concentrations of digitonin (0.1%, w/v) cause stimulation of the enzyme activity in membranes; treatment with higher concentrations of digitonin (1-10%) results in solubilization of up to 70% of the digitonin-stimulated activity . The digitonin-solubilized enzyme displays regulatory properties quite similar to those of the membrane-bound form of the enzyme, showing specific activation by GTP . GTP activation requires the presence of a protein factor which can be separated from the enzyme by washing the membranes prior to enzyme solubilization . Association of this protein factor with the membrane-bound enzyme is promoted by polyethylene glycol or by Ca2+; however, these compounds are ineffective in enhancing enzyme-factor association for the enzyme in the solubilized state . The observation that Ca2+ promotes enzyme-factor association in the membranes suggests that this cation, in addition to GTP, may play a role in the regulation of cellulose synthesis in vivo in A . xylinum.

J Bacteriol, 1983 Apr, 154(1), 185 - 91
Proton efflux coupled to dark H2 oxidation in whole cells of a marine sulfur photosynthetic bacterium (Chromatium sp . strain Miami PBS1071); Kumazawa S et al.; Whole cells of photoanaerobically grown Chromatium sp . strain Miami PBS1071, a marine sulfur purple bacterium, oxidized H2 in the dark through the oxyhydrogen reaction at rates of up to 59 nmol of H2 per mg (dry weight) per min . H2 oxidation was routinely measured in H2 pulse experiments with air-equilibrated cells . The reaction was accompanied by a reversible H+ efflux from the cells, suggesting an outward H+ translocation reaction coupled to H2 oxidation . The H+/e- ratio, calculated from simultaneous measurements of H2, O2, and H+ changes in the medium, varied with the cultures from 0.7 to 1.2 . The ratio increased considerably when the backflow of H+ was taken into account . Anaerobic H2 uptake with 2,5-dimethyl-p-benzoguinone as an oxidant also showed a weak H+-translocating activity . No H+-translocating activity was detected with methylene blue as an oxidant . Carbonylcyanide 3-chlorophenylhydrazone (1 microM) stimulated H2 oxidation and abolished the associated H+ changes when H2 oxidation was observed in O2 pulse experiments with H2-Ar-equilibrated cells . However, the uncoupler inhibited both H2 oxidation and H+ changes when measurements were made in H2 pulse experiments with air-equilibrated cells . It is suggested that in this bacterium the susceptibility of hydrogenase to reversible O2 inactivation in situ is enhanced by the presence of uncoupling agents.

J Periodontol, 1983 Apr, 54(4), 193 - 6
Suppression of penicillin-resistant oral Actinobacillus actinomycetemcomitans with tetracycline . Considerations in endocarditis prophylaxis; Slots J et al.; Actinobacillus actinomycetemcomitans is an oral bacterium which is being encountered with increasing frequency in infective endocarditis . This organism occurs in high numbers in periodontitis lesions of patients with localized juvenile periodontitis (periodontosis) . It is present infrequently, and only in low numbers in most other individuals . Its common resistance to penicillin, erythromycin and vancomycin represents a clinical problem in patients at risk of developing endocarditis after dental treatment . However, the high activity of tetracyclines against A . actinomycetemcomitans may be useful in prophylactic endocarditis considerations by allowing a suppression of the organism prior to the institution of recommended prophylactic protocols . In this study, we determined the effect of systemic tetracycline-HCl therapy (1 gm/day) on the oral A . actinomycetemcomitans population in five localized juvenile periodontitis patients who were heavily infected with the organism . A . actinomycetemcomitans could not be detected in samples of subgingival and supragingival dental plaque and cheek mucosal surfaces following 14 days of administration of systemic tetracycline . The organism was still undetectable 3 weeks after therapy but it reappeared at a few oral sites at week 8 post-treatment . On the basis of this data, it is proposed that the prophylactic endocarditis therapy of patients with high numbers of penicillin-resistant A . actinomycetemcomitans include a two-stage approach: first, the systemic administration of tetracycline for 14 days, and second, institution of a conventional prophylactic protocol during the time of dental treatment.

Arch Biochem Biophys, 1983 Apr 1, 222(1), 78 - 86
Partial purification and characterization of two soluble c-type cytochromes from Chromatium vinosum; Gray GO et al.; Two c-type cytochromes from Chromatium vinosum have been partially purified and characterized . Cytochrome c550, which appears to function as an electron carrier in the cyclic electron transport chain of this photosynthetic purple sulfur bacterium, has a molecular weight of approximately 15,000 and an oxidation-reduction midpoint potential (Em) of +240 mV at pH 7.4 . It has (in the reduced form) an alpha band at 550 nm and a beta band at 520 nm . Cytochrome c551 is characterized by absorbance maxima at 354 and 409 nm in the oxidized form and 418, 523, and 551 nm in the reduced form . The reduced cytochrome reacts with CO . Cytochrome c551 is a monomeric protein with a molecular weight of 18,800 +/- 700 and Em = -299 +/- 5 mV (pH independent between pH 6.3 and 8.0) . It appears to lack a methionine axial ligand as indicated by the absence of an absorbance band at 695 nm in the oxidized form.

J Bacteriol, 1983 Apr, 154(1), 58 - 64
Cloning and orientation of the gene encoding polynucleotide phosphorylase in Escherichia coli; Crofton S et al.; Mutations which affect the activity of polynucleotide phosphorylase (PNPase) map near 69 min on the bacterial chromosome . This region of the chromosome has been cloned by inserting the kanamycin-resistant transposon Tn5 near the argG and mtr loci at 68.5 min . Large SalI fragments of chromosomal DNA containing the Tn5 element were inserted into pBR322, and selection was made for kanamycin-resistant recombinant plasmids . Two of these plasmids were found to produce high levels of PNPase activity in both wild-type and host strains lacking PNPase activity . The pnp gene was further localized and subcloned on a 4.8 kilobase HindIII-EcoRI fragment . This fragment was shown to encode an 84,000-molecular weight protein which comigrated with purified PNPase during sodium dodecyl sulfate-polyacrylamide gel electrophoresis . The orientation of the pnp gene was determined by insertion of Tn5 into the 4.8 kilobase fragment cloned in pBR322 . Some of the insertions had lost the ability to elevate the level of PNPase activity in the host bacterium . Restriction mapping of the positions of the Tn5 insertions and analysis of plasmid-encoded polypeptides in UV-irradiated maxi-cells indicated that the pnp gene is oriented in the counterclockwise direction on the bacterial chromosome.

Am Ind Hyg Assoc J, 1983 Mar, 44(3), 156 - 60
An outbreak of acute fever among steam turbine condenser cleaners; Lauderdale JF et al.; Ten of twelve men who participated in the cleaning of an electric power steam turbine condenser clogged with freshwater sponge experienced an acute febrile illness . Two similar outbreaks have been previously described, one of which has been attributed to the Legionnaires' Disease bacterium . Epidemiologic studies of this case showed a syndrome very similar to the two previously reported episodes . However, the exact etiology for this outbreak has not been identified . Environmental sampling was not initiated until after the cleaning was completed . Subsequent testing did not reveal any likely cause for the outbreak . The delayed onset of symptoms and the nature of the illness pointed to an infectious agent . In the absence of any suitable criteria for employee exposure evaluation, it is suggested that crews cleaning condensers under unusually dirty conditions, especially if eye or respiratory symptoms are reported, should be provided with respiratory protection.

Proc Natl Acad Sci U S A, 1983 Mar, 80(6), 1669 - 73
Bacterial and phage mutations that reveal helix-unwinding activities required for bacteriophage T4 DNA replication; Gauss P et al.; An Escherichia coli strain with a mutation in the optA gene restricts the growth of bacteriophage T4 strains partially defective in gene 43 (DNA polymerase) or missing gene dda (DNA-dependent ATPase) . The mutations in the dda gene inactivate a DNA-dependent ATPase that has been shown to have DNA helicase activity in vitro . We show that the restriction of phage growth after infection of the optA bacterium is the result of a block in DNA replication . We infer that the block arises from a defect in DNA unwinding.

FEBS Lett, 1983 Feb 21, 152(2), 251 - 5
Characterization of a new membrane-bound cytochrome c of Rhodopseudomonas capsulata; Hudig H et al.; A cytochrome c (cyt . c) was solubilized with Triton-X-100 and co-purified with cytochrome c oxidase from membranes of chemotrophically grown cells of Rhodopseudomonas capsulata . Cyt . c and cytochrome oxidase were separated on Sephadex G-50 columns . Antibodies against cytochrome c2 from the same bacterium did not cross react with the membrane-bound cyt . c . The IEP of the membrane-bound cyt . c was found to be pH 8.2, the midpoint potential was 234 +/- 11 mV at pH 7.0 . This cyt . c binds CO . The native cyt . c is a dimer with an apparent Mr of 25000 containing 2 mol heme per mol dimer, which is believed to function as an electron donor for the high-potential cytochrome c oxidase.

J Bacteriol, 1983 Feb, 153(2), 867 - 71
Energy coupling to nitrite respiration in the sulfate-reducing bacterium Desulfovibrio gigas; Barton LL et al.; By use of a membrane fraction prepared from Desulfovibrio gigas grown in a lactate-sulfate medium, synthesis of ATP was demonstrated to be coupled to the oxidation of molecular hydrogen and reduction of either nitrite or hydroxylamine . This phosphorylation was uncoupled from electron transport by pentachlorophenol, methyl viologen, and gramicidin, but not by oligomycin . The extrusion of protons from the cells was shown to be coupled to the hydrogen-nitrite respiratory system, and, assuming the localization of nitrite reductase on the outer side of the plasma membrane, H+/2e- values of 2.0 +/- 0.3 were obtained . Energy coupling observed with this system appears to be due to electron transfer-coupled proton translocation rather than vectorial electron transfer associated with hydrogen oxidation.

J Bacteriol, 1983 Feb, 153(2), 652 - 7
Genetic transformation of obligately chemolithotrophic thiobacilli; Yankofsky SA et al.; Genetic transformation of Thiobacaillus thioparus auxotrophs to prototrophy was obtained at frequencies of up to 10(-2) when proliferating cell populations were exposed to chromosomal DNA from a nutritionally independent strain of the same bacterium . The rate at which transformation occurred depended on recipient growth rate and could be drastically reduced by depriving otherwise competent cells of either nitrogen or exogenous energy substrate . Interspecies marker transfer was also shown among several obligately chemolithotrophic members of the genus.

Biochem J, 1983 Feb 1, 209(2), 445 - 54
Purification and properties of the membrane-bound by hydrogenase from Desulfovibrio desulfuricans; Lalla-Maharajh WV et al.; The membrane-bound hydrogenase from the anaerobic sulphate-reducing bacterium Desulfovibrio desulfuricans (Norway strain) has been purified to homogeneity, with an overall 80-fold purification and a specific activity of 70 mumol of H2 evolved/min per mg of protein . The hydrogenase had a relative molecular mass of 58 000 as determined by gel filtration and was estimated to contain six iron atoms and six acid-labile sulphur groups per molecule . The absorption spectrum of the enzyme was characteristic of an iron-sulphur protein . The E400 and E280 were 28 500 and 109 000 M-1.cm-1 respectively . The e.s.r . of the oxidized protein indicated the presence of {4Fe-4S}3+ or {3Fe-3S}3+, and another paramagnetic centre, probably Ni(III) . The hydrogenase was inhibited by heavy-metal salts, carbon monoxide and high ionic strength . However, it was resistant to inhibition by thiol-blocking and metal-complexing reagents . N-Bromosuccinimide totally inhibited the enzyme activity at low concentrations . The enzyme was stable to O2 over long periods and to high temperatures . It catalyses both H2-evolution and H2-uptake with a variety of artificial electron carriers . D . desulfuricans cytochrome C3, its natural electron carrier, had a high affinity for the enzyme (Km = 2 microns) . Rate enhancement was observed when cytochrome C3 was added to Methyl Viologen in the H2-evolution assay . The pH optimum for H2-evolution was 6.5.

J Bacteriol, 1983 Feb, 153(2), 1060 - 2
Evidence for a plasmid in a methanogenic bacterium; Thomm M et al.; Among 15 strains of methanogens, one plasmid, pMP1, was identified in the new coccoid isolate PL-12/M . It could not be detected in the cleared lysate, but it was detected in the viscous pellet . The plasmid had a molecular weight of ca . 4.6 x 10(6) . A restriction enzyme cleavage map of the cloned plasmid was derived.

Fortschr Med, 1983 Jan 27, 101(4), 113 - 7
{The significance of Peyer's plaques for intestinal immunity . Animal experimental inferences}; Enders G et al.; The removal of Peyer's patches alters the first line of defence against a known bacterium . Whereas in control animals all reactive cells could be found within the lamina propria of the gut, in rats without Peyer's patches only small amounts of IgA and IgM secreting cells could be detected there . In contrast IgA and IgM secreting cells could be found within mesenteric lymph nodes and spleen . The removal of the Peyer's patches diminishes the reaction of the lamina propria . Therefore other lymphatic structures like mesenteric lymph nodes and spleen get contact with antigenic material and generate E . coli specific immune globulin secreting cells . These cells were able to secrete IgA which was detected within the bile . This compensatory mechanism helps to restore the disturbed balance . The consequence of the systemic reaction against the E . coli must be discussed in view of cross reacting antibodies or the generation of inflammatory cells within the gut.

Cell Motil, 1983, 3(1), 93 - 103
Invited review: bacterial flagellar sheaths: structures in search of a function; Sjoblad RD et al.; Although bacterial flagellar sheaths were observed over 30 years ago, they may still be characterized as structures in search of a function . In addition to true sheaths, bacterial flagella may possess other adornments that cause an increase in the organelle's cross-sectional diameter . These "complex flagella" are sharply differentiated from sheathed flagella . Immunological and chemical distinctions have been found between flagellar sheaths, flagellar cores, and LPS layers inferred to be the sheath sensu stricto . Although complex flagella may serve as specific receptors for flagellotropic phages or in allowing for more efficient swimming in viscous environments, similar functions have not yet been attributed to true sheaths . It is postulated that flagellar sheaths may allow for specific interaction between a bacterium and a surface . In addition, there is a problem as to the relationship between a rapidly rotating flagellum and the sheath.

J Comp Pathol, 1983 Jan, 93(1), 115 - 26
An in vivo method of assay for Dermatophilus congolensis; Davis D; An in vivo method of assay for Dermatophitus congolensis in rats is described . The optimal conditions for preparing skin before infection and subsequently harvesting the zoospores from infected skin were investigated . These experiments showed that clipping the skin had no effect on infection with this bacterium and that when the infected skin was soaked in water, increased amounts of dissolved CO2 had no effect on the release of zoospores, which was maximal within 2.5 h of immersion . Vaccination studies demonstrated that this assay gave results comparable to previously published data, where these data were quantitative . Infection with D . congolensis was not related to the production of exudate on the skin surface . This is the first report that D . congolensis can infect skin without producing an exudate . Hypotheses linking skin damage and susceptibility to infection with this bacterium are discussed in the light of this observation.

Comp Immunol Microbiol Infect Dis, 1983, 6(3), 227 - 34
Transmission studies with the contagious equine metritis bacterium in albino Swiss mice; Timoney PJ et al.; Aspects of experimental transmission of the causal bacterium of contagious equine metritis (CEM) to albino Swiss mice were investigated . Whereas infection was established in the majority of female mice, the organism was recovered from only a limited number of male mice after challenge . No clinical evidence of infection was observed in the experimental mice . There was only one instance of presumptive venereal transmission of the CEM bacterium . One third of infected females conceived and had normal litters.

J Cell Biochem, 1983, 22(4), 251 - 61
Primary photochemistry in the facultative green photosynthetic bacterium Chloroflexus aurantiacus; Blankenship RE et al.; The mechanism of primary photochemistry has been investigated in purified cytoplasmic membranes and isolated reaction centers of Chloroflexus aurantiacus . Redox titrations on the cytoplasmic membranes indicate that the midpoint redox potential of P870, the primary electron donor bacteriochlorophyll, is +362 mV . An early electron acceptor, presumably menaquinone has Em 8.1 = -50 mV, and a tightly bound photooxidizable cytochrome c554 has Em 8.1 = +245 mV . The isolated reaction center has a bacteriochlorophyll to bacteriopheophytin ratio of 0.94:1 . A two-quinone acceptor system is present, and is inhibited by o-phenanthroline . Picosecond transient absorption and kinetic measurements indicate the bacteriopheophytin and bacteriochlorophyll form an earlier electron acceptor complex.

Microbiol Immunol, 1983, 27(10), 847 - 59
Relationship between luminous fish and symbiosis . I . Comparative studies of lipopolysaccharides isolated from symbiotic luminous bacteria of the luminous marine fish, Physiculus japonicus; Kuwae T et al.; In order to investigate the relationship between host and symbiosis in the luminous marine fish, Physiculus japonicus, the bacterial lipopolysaccharides (LPS) of symbiotic luminous bacteria were compared serologically and electrophoretically . Five symbiotic luminous bacteria (PJ strains) were separately isolated from five individuals of this fish species caught at three points, off the coasts of Chiba, Nakaminato, and Oharai . LPS preparations were made from these bacteria by Westphal's phenol-water method and highly purified by repeated ultracentrifugation . These LPSs contained little or no 2-keto-3-deoxyoctonate and had powerful mitogenic activity . In sodium dodecylsulfate polyacrylamide gel electrophoresis, these PJ-1 to -5 LPSs were separated by their electrophoretic patterns into three groups; the first group included PJ-1 and PJ-4, the second group PJ-2 and PJ-3, and the third group PJ-5 alone . The results agreed with those of the double immunodiffusion test; precipitin lines completely coalesced within each group but not with other groups . In immunoelectrophoresis, one precipitin line was observed between anti PJ-2 LPS serum and PJ-5 LPS but the electrophoretic mobility of PJ-5 LPS was clearly different from that of the PJ-2 LPS group . Furthermore, in a 50% inhibition test with PJ-2 LPS by the passive hemolysis system, the doses of PJ-2 LPS, PJ-3 LPS, and PJ-5 LPS required for 50% inhibition (ID50) in this system were 0.25, 0.25, and 21.6 micrograms/ml for each alkali-treated LPS, respectively, and the ID50's of both PJ-1 LPS and PJ-4 LPS were above 1,000 micrograms/ml . These results indicate that PJ-5 LPS has an antigenic determinant partially in common with LPS from the PJ-2 group but not with LPS from the PJ-1 group and that the symbiotic luminous bacterium PJ-5 is more closely related to the PJ-2 group than to the PJ-1 group . These results show that the species Physiculus japonicus is symbiotically associated with at least three immunologically different strains of luminous marine bacteria in its specialized light organ.

Z Allg Mikrobiol, 1983, 23(7), 457 - 65
A novel MN2+-oxidizing enzyme system in a freshwater bacterium; Zindulis J et al.; Manganese oxidation by cell suspensions and cell extracts of a freshwater bacterium, designated strain FMn 1, was investigated . Manganese appeared to be oxidized in the periplasmic space . A conventional, membrane-bound-electron transport system was not utilized . An enzyme or enzyme complex and a cofactor, each of different molecular size, were located in different parts of the cell envelope . Results suggest that the cofactor reacts with manganese in the periplasmic space and that in the presence of oxygen it is reoxidized by the enzyme . The enzyme is probably loosely bound to the membrane . A combination of enzyme and cofactor in a crude preparation exhibited a pH optimum at around 7.0 . The enzyme exhibited a temperature optimum at around 30 degrees C . No temperature optimum was found for the cofactor . The enzyme was heat-stable and could oxidize manganese under anaerobic conditions . The enzyme system appears to be different from others so far described.

Microbios, 1983, 38(151), 43 - 9
Simple devices for measuring antibiotic zone inhibition; Mates A; A chart has been developed for rapid reading of antibiotic zone inhibition . This method enabled the recording of whether the bacterium was sensitive or resistant to a drug in vitro . Two other devices were developed, for accurately reading the actual zone of inhibition when a clear medium was used, and also when an opaque medium was utilized.

Int J Radiat Biol Relat Stud Phys Chem Med, 1983 Jan, 43(1), 85 - 90
The role of cellular catalase on the radiosensitization of bacterial vegetative cells by N2O; Watanabe H et al.; The effect of N2O on eight strains of bacteria was measured in dilute suspensions . The dose-modifying factors (DMF) of N2O on M . radiodurans R1, P . radiora 0-1, M . lysodeikticus and B . pumilus E601 (vegetative cells) were 3 . 4, 2 . 9, 2 . 4 and 1 . 7, respectively . But P . radiora RP-C, P . fluorescens B3-1, E . coli B/r and E . coli K-12 were hardly sensitized by N2O . From measurements of catalase activity of each bacterium, it was found that the DMF increases with increased catalase activity, suggesting that cellular catalase promotes the sensitizing action of N2O.

Arch Microbiol, 1983 Jan, 134(1), 45 - 8
Methylamine metabolism and its role in nitrogenase "switch off" in Rhodopseudomonas capsulata; Yoch DC et al.; In the photosynthetic bacterium Rhodopseudomonas capsulata, NH4+ switch-off of nitrogenase activity can be mimicked by its analog, methylamine . Like NH4+, methylamine appeared to require processing by glutamine synthetase (GS) before it was effective; gamma-glutamylmethylamide was shown to be the product of this reaction . Evidence that this glutamine analog functioned directly to initiate nitrogenase inactivation was suggested first by the fact that it was a poor substrate for glutamate synthase (i.e., it was not further metabolized by this pathway) and secondly, azaserine which blocks the transfer of the glutamine amide group had no effect on CH3NH3+ (or NH4+) switch-off . These observations are taken as preliminary evidence to suggest that when NH4+ inhibits nitrogenase activity, inactivation is initiated by glutamine itself, and not a molecule derived from it . Finally, evidence was presented that R . capsulata would use CH3NH3+ as a nitrogen substrate, but lag periods and generation times increased with subsequent passages.

Arch Oral Biol, 1983, 28(3), 247 - 52
Colonization of the teeth of rats by human and rodent oral strains of the bacterium Actinomyces viscosus; de Jong MH et al.; The mouths of rats were infected with human and rodent strains of A . viscosus and streptomycin-rifamycin-resistant (SR) mutants of these strains . The establishment, adherence to the teeth and cell dose required for infection were determined . Human and rodent strains established equally well on the teeth and did not differ in their initial adherence to teeth . The cell dose required for infection was much lower for rodent than for human strains (less than 10(5) compared to 10(7) - 10(8) c.f.u.) . The SR mutants established as well as their parents except for one SR strain, that did not establish at all . Another SR mutant appeared to have lost its SR resistance after passage through the animal . The results stress the need of in-vivo testing of antibiotic resistant mutants to be used in ecological studies.

Acta Microbiol Hung, 1983, 30(2), 99 - 102
Use of reducing compounds in the cultivation of Azospirillum sp; Venkateswarlu B et al.; Attempts were made to grow the micro-aerophilic N2-fixing bacterium Azospirillum sp . in complete liquid medium by incorporating some reducing agents . Ascorbic acid, glutathione and Na-thioglycollate stimulated while methylene blue inhibited the growth and N2-ase activity . In complete liquid medium, Na-thioglycollate and ascorbic acid increased the N2-ase activity with increasing concentration up to 800 micrograms/ml . With glutathione, growth of the bacterium was increased markedly but N2-ase activity was repressed below 200 micrograms/ml . The possibility of employing these compounds for the cultivation of Azospirillum in complete liquid medium seems to be indicated.

Cell Tissue Res, 1983, 233(2), 295 - 303
Induction of degranulation and lysis of haemocytes in the freshwater crayfish, Astacus astacus by components of the prophenoloxidase activating system in vitro; Smith VJ et al.; To study the role of the prophenoloxidase activating system, an enzyme cascade located in the haemocytes of crustaceans, in the cellular defences of the freshwater crayfish, Astacus astacus in vitro, monolayer cultures of mixed or separated haemocyte populations, isolated by density gradient centrifugation, were challenged with the bacterium, Moraxella sp . pre-coated with phenoloxidase and the other attaching proteins in crayfish haemocyte lysate (HLS), or in the case of controls, with saline or Moraxella sp . pre-incubated in saline alone . Examination of the coverslips 1 h after inoculation revealed that, in the mixed haemocyte cultures, most of the cells had undergone profound degranulation and lysis following exposure to the HLS-coated bacteria . Cell lysis was also evident in the experimental semigranular cell monolayers, but not in the controls, although in those controls treated with the saline-incubated bacteria, the semigranular haemocytes had undergone degranulation without lysis . In contrast, the granular cells appeared to be unaffected by the saline-incubated Moraxella sp., and with the HLS-coated bacteria displayed only marked degranulation . Greater numbers of bacteria were always associated with the cells or cell remnants in the experimental cultures compared to the controls . We suggest that the attaching proteins of the prophenoloxidase cascade are strong nonself signals for the haemocytes, causing them to degranulate and release previously cell-bound recognition factors into the haemolymph, where they are free to trigger activation of adjacent haemocytes.

J Biochem (Tokyo), 1983 Jan, 93(1), 159 - 67
Action of chlorophyllase purified from rye seedlings on light-harvesting bacteriochlorophyll of chromatophores and spheroplasts from Rhodospirillum rubrum; Tanaka K et al.; 1 . The chlorophyllase {EC 3.1.1.14} purified from greened rye seedlings hydrolyzed the bacteriochlorophyll isolated from Rhodospirillum rubrum, but not the pigment bound to the membrane of chromatophores or spheroplasts from the bacterium . 2 . Acetone, if added at such concentrations that the bound bacteriochlorophyll would not be solubilized, enabled the enzyme to hydrolyze the bound pigment . The acetone concentrations required for half the maximum hydrolysis rates were 16% with chromatophores and 7% with spheroplasts . 3 . The enzymic hydrolysis of the bound bacteriochlorophyll in the presence of acetone removed bacteriochlorophyllide from the membrane, leaving its esterifying alcohol, possibly all-trans-geranylgeraniol, in situ . 4 . Washing of chromatophores with 30% acetone removed about 10% of the bound bacteriochlorophyll . The bound pigment remaining after washing was not hydrolyzed by the enzyme unless acetone was added . 5 . It seems possible that light-harvesting bacteriochlorophyll was mostly, if not all, bound to the inner surface of chromatophores (the outer surface of spheroplasts), having its esterifying alcohol residue buried in the membrane and its porphyrin residue emerging from the membrane into the inside solution; thus, chlorophyllase could not make contact with the ester linkage between the esterifying alcohol and porphyrin moieties of the pigment unless the esterifying alcohol residue was partly exposed.

J Mol Evol, 1983, 19(6), 455 - 62
The protein burden of lac operon products; Koch AL; A new approach to measuring the slowing of growth due to the manufacture of proteins not needed by a bacterium is presented . An entire single colony of Escherichia coli was used to start a chemostat culture that was then given a selective pressure by the addition of phenylgalactoside (phi-gal) . This enriched the population for constitutive mutants that produced beta-galactosidase without induction and could split phi-gal, consume the galactose, and grow faster . When the phi-gal was removed, the constitutives grew slower than the parental strain and were gradually lost . This procedure allows competition experiments to be carried out with minimum effects due to genetic drift . Experiments with both strains having wild-type and mutant permease genes were conducted . With the former the selective disadvantage was initially much greater than expected from the simplest hypothesis that extra unused proteins would slow growth in proportion to their fraction of the total protein synthesis . This phase was followed by a second phase where the selective disadvantage was smaller than predicted by this simple hypothesis . With a very slowly reverting permease negative strain the selective disadvantage, and therefore the protein burden, was found to be much smaller and not statistically different from zero . Thus, while one would expect under carbon and energy limitation in the chemostat the protein burden to be larger than under unlimited conditions, it is so small that even the refined technique used here could not measure it accurately . It is certainly less than the fraction of 'waste' protein synthesis; but it could be between zero and the fraction of the cells' energy and carbon budget spent on manufacture of the proteins of the lac operon.

Ann Rech Vet, 1983, 14(3), 265 - 70
{Attempt at the experimental reproduction of rotavirus diarrhea in newborn calves deprived of colostrum}; Schwers A et al.; Colostrum-deprived newborn calves were orally inoculated with different doses of cell-culture bovine rotavirus or with bacterium-free filtrates of calf stools containing rotavirus . None of the animals that received high doses of cell-culture rotavirus developed diarrhoea or any other clinical sign, although all of them excreted virus for several days and produced specific antibodies; calves inoculated with lower doses of cell-culture virus or with stool filtrates showed a transient diarrhoea 48 h after inoculation . Such paradoxical results might be due to a phenomenon of interference, as bovine rotavirus is susceptible to interferon . In experimental conditions, rotavirus produces only a mild and transient diarrhoea: this contrasts with the situation observed in farms, where that virus may provoke important problems . In association with the virus itself, numerous other factors such as the environmental conditions or the response of the calf to the infection also play a role in the evolution of the disease.

Mol Gen Genet, 1983, 191(1), 99 - 109
In situ transposon replacement and isolation of a spontaneous tandem genetic duplication; Avery L et al.; Using a specialized transducing P1 phage carrying an insertion of Tn5-132, an insertion of Tn5-wt in the chromosome of Myxococcus xanthus, which codes for resistance to kanamycin, can be replaced with one of Tn5-132, which codes for resistance to tetracycline . That Tn5-132 in the daughter is inserted at the same location in the chromosome as Tn5-wt was in the parent was shown by a variety of physical and genetic tests . Southern blot hybridizations of restriction digests of daughter and parent DNAs probed for sequences homologous to Tn5 show that the physical location is the same . When KmR was transduced from the parent to the TcR daughter by the generalized transducing myxophage Mx4 or Mx8, all the transductants were TcS . Likewise, when the daughter was used as donor, TcR transductants of its KmR parent were KmS . Flanking markers that were linked to KmR in the parent were linked to TcR in the daughter . Spontaneous tandem genetic duplications of portions of bacterial chromosomes can be trapped by transducing a selectable marker from a donor to a recipient that has a different selectable marker at the same genetic location and selecting transductants with both markers . Using Tc-replacement, this technique can be applied to any region of the chromosome . We used it to isolate a spontaneous tandem duplication of part of the M . xanthus chromosome . The duplication was characterized by Southern blot hybridizations probed for Tn5-homologous DNA . It was also shown to be unstable by quantitation of loss of drug resistance . Transduction of the novel joint led to reconstruction of the duplication in the recipient strain . All these tests gave results consistent with the proposed structure . The methods described here are applicable to any bacterium into which transposons can be introduced, and for which some means of genetic exchange is available.

J Bacteriol, 1983 Jan, 153(1), 371 - 4
Effect of starvation on cytoplasmic pH, proton motive force, and viability of an acidophilic bacterium, Thiobacillus acidophilus; Zychlinsky E et al.; The question of whether Thiobacillus acidophilus maintains its cytoplasmic pH at values close to neutrality by active or passive means was explored by subjecting the organism to long-term starvation (up to 22 days) . Starving cells maintained a delta pH of 2 to 3 U throughout starvation, although cellular poly-beta-hydroxybutyric acid and ATP, the proton motive force, and culture viability were low or not detectable after 200 h . Cells exposed to azide or azide plus N,N'-dicyclohexylcarbodiimide immediately exhibited characteristics of cells starved for more than 200 h . Thus, a large delta pH in T . acidophilus was maintained in the absence of ATP, ATPase activity, respiration, significant levels of proton motive force, and cell viability and was therefore not dependent on chemiosmotic ionic pumping . The transition from a metabolically active to an inactive state was accompanied by a large increase in the positive membrane potential, which nearly completely compensated for the delta pH in the inactive cells . The longevity of the acidophile during starvation was comparable to that reported previously for neutrophiles, and the loss of viability occurred not because of the acidification of the cytoplasm but apparently because of energy depletion.

J Infect, 1983 Jan, 6(1), 75 - 80
Cardiobacterium hominis: an elusive cause of endocarditis; Lane T et al.; Cardiobacterium hominis is a fastidious bacterium of the normal mouth flora . It has rarely been recognised in the past as a human pathogen and has been difficult to recover from the bloodstream . Mistaken diagnoses and delays in therapy have been common . We report a 29-year-old man with C . hominis endocarditis who was initially treated for a presumed collagen-vascular disorder with anti-flammatory drugs . The organism was eventually recovered in brain-heart infusion medium after prolonged incubation, and cure was accomplished with parenteral penicillin . Special blood culturing methods should be used if endocarditis caused by a fastidious organism is clinically suspected.

Mol Gen Genet, 1983, 189(2), 207 - 10
Ribosomal RNA genes of Neurospora crassa: multiple copies and specificities; Dutta SK et al.; Ribosomal RNA genes were isolated from the germinated conidial and mycelial cells of N . crassa by repeated cycles of 3H-DNA:rRNA reactions followed by hydroxyapatite chromatography . Specificity of multiple copies of those rDNAs with respect to N . crassa cell types was studied . The fraction of N . crassa germinated conidial in vitro labelled 3H-DNA recovered in the presence of rRNA isolated from the same cell type was about 2.2%, when compared with approximately 1.2% rDNAs obtained in mycelial cells . These isolated rDNAs reacted specifically to 26S and 17S rRNAs of eukaryotic (N . crassa) organisms and did not react with 4S tRNAs . rRNA:rDNA reassociation kinetics studies indicate that 90% of the rRNA genes were homogeneous and not identical with the other 10% rRNA genes isolated from N . crassa mycelia . These studies suggest that the possible heterogeneity of rDNA sequences of N . crassa cannot be attributed to inclusion of any tDNA sequences as has been shown in the heterogeneity of rDNA sequences of the bacterium Escherichia coli . The heterogeneity of multiple copies of N . crassa rDNAs could be due to differences in internal or external spacer regions of N . crassa rRNA genes.

Arch Oral Biol, 1983, 28(11), 981 - 7
Cytotoxicity of the bacterium Actinobacillus actinomycetemcomitans extracts in human gingival fibroblasts; Stevens RH et al.; Filter-sterilized sonic extracts (SE) of strains of Actinobacillus actinomycetemcomitans were shown to inhibit the proliferation of human gingival fibroblasts in vitro . The inhibition was dose-dependent: a 50 per cent inhibitory dose of 2 micrograms protein/ml was found for A . actinomycetemcomitans strain Y4 . The inhibitory activity could be neutralized by homologous antiserum and was heat inactivated by temperatures of 80 degrees C or greater . The fibroblast-inhibitory activity was present in SEs of both leukotoxic-producing and non-leukotoxic strains of A . actinomycetemcomitans, suggesting that a separate agent is responsible for leukotoxicity and fibroblast inhibition . A short (10 min) exposure of the fibroblasts to the A . actinomycetemcomitans SE was sufficient to inhibit irreversibly cell proliferation, provided that serum was present at the time that the cells were exposed to the SE . SE-challenged fibroblasts exhibited a marked decrease in the rate of DNA synthesis, but no inhibition of RNA or protein synthesis . Although the SE-treated cells did not proliferate, they appeared to remain intact and viable; and displayed no gross morphological alterations.

J Clin Invest, 1983 Jan, 71(1), 1 - 8
Specific adherence of Escherichia coli (strain RDEC-1) to membranous (M) cells of the Peyer's patch in Escherichia coli diarrhea in the rabbit; Inman LR et al.; The RDEC-1 strain Escherichia coli is an enteroadherent bacterium that produces diarrhea in the rabbit . A histopathologically similar disease has been described in humans . The RDEC-1 bacterium adheres to the epithelium of lymphoid follicles in rabbit ileal Peyer's patches by 4 h postinoculation, 3-4 d before its adherence to absorptive epithelium . The purpose of this study was to determine whether the RDEC-1 bacterium adheres to a specific cell type in the lymphoid follicle epithelium . RDEC-1 bacteria were given in a dose of 2 X 10(6) by the orogastric route to postweanling rabbits . The distal ileal Peyer's patch, taken from 5 control rabbits and 43 rabbits at intervals in the first 24 h postinoculation, was examined by routine and high-voltage electron microscopy . The RDEC-1 bacterium adhered specifically to M (membranous) rather than absorptive epithelial cells of the lymphoid follicle epithelium . Further understanding of how the bacterium attaches to M cells, which transport antigens to intraepithelial lymphocytes, could be useful in designing vaccines to protect mucosal surfaces.

J Biol Chem, 1982 Dec 25, 257(24), 14714 - 8
Purification and characterization of membrane-bound ferrochelatase from Rhodopseudomonas sphaeroides; Dailey HA; Ferrochelatase (protohaem ferro-lyase EC 4.99.1.1) has been purified to apparent homogeneity from the facultative photosynthetic bacterium Rhodopseudomonas sphaeroides . The enzyme has been purified 1,640-fold with 43% recovery from isolated membrane fragments . The enzyme has a molecular weight of approximately 115,000 as estimated by both sodium dodecyl sulfate-polyacrylamide gel electrophoresis and gel filtration chromatography through Sephadex G-150 in the presence of 0.5% sodium deoxycholate . The purification procedure involves solubilization of ferrochelatase with sodium deoxycholate off of salt-washed membranes, followed by ammonium sulfate fraction, ion exchange chromatography on DEAE-Sephacel, followed by chromatography on Amicon dye matrix blue B, and finally Sephadex G-150 . The enzyme has an extinction coefficient of 90,000 at 278 nm, and the absorption spectrum reveals no chromophoric cofactors . Purified ferrochelatase is inhibited by iodoacetamide, N-ethylmaleimide, Hg, Pb, Cu, and hemin . The apparent Km values are for mesoporphyrin IX, 20 microM; deuteroporphyrin IX, 95 microM; and iron, 20 microM.

Appl Environ Microbiol, 1982 Dec, 44(6), 1421 - 7
Isolation and characterization of a pentachlorophenol-degrading bacterium; Stanlake GJ et al.; With a new enrichment protocol, pentachlorophenol (PCP)-degrading bacteria were isolated from soil, water, and sewage . When characterized, all isolates were related and shared characteristics of the genus Arthrobacter . Growth rates for strain NC were determined for a number of substrates, including PCP and 2,4,6-trichlorophenol . Changes in PCP concentration affected growth rate and length of the lag phase but not cell yield . Increasing the pH from 6.8 to 7.8 decreased the length of the lag phase for growth on PCP . Cessation of growth, upon incremental addition of PCP, was found to be related to a decrease in pH rather than to a buildup of a toxic metabolite . Degradation of PCP by strain NC was shown to be complete.

Gene, 1982 Dec, 20(3), 433 - 39
A Dictyostelium discoideum DNA fragment complements a Saccharomyces cerevisiae ura3 mutant; Boy-Marcotte E et al.; Dictyostelium discoideum DNA fragments have been inserted into the chimeric bacterium-yeast plasmid YEp13 . Recombinant plasmids were used to transform yeast using a strain of Saccharomyces cerevisiae deficient in OMP decarboxylase activity . Several clones were selected for growth in uracil-free medium . One clone was further analysed and contains a plasmid with a segment of D . discoideum DNA which complements a yeast ura3 mutation.

Ann Intern Med, 1982 Dec, 97(6), 809 - 13
Legionella wadsworthii species nova: a cause of human pneumonia; Edelstein PH et al.; A new species of Legionella that caused pneumonia in a patient with chronic lymphocytic leukemia has been characterized . The Legionella wadsworthii species nova is proposed for this bacterium . The type strain is Wadsworth 81-716A (American Type Culture Collection 33877) . The new species differs phenotypically from L . pneumophila in that the predominant cellular fatty acid is methyl-12-methyltetradecanoic acid (a-15:0) rather than methyl-14-methylpentadecanoic acid (i-16:0), and in its failure to react with L . pneumophila antiserum . The clinical illness caused by L . wadsworthii was not apparently different from that seen with other legionella infections, except for prolonged fever and slow resolution of pulmonary infiltrates.

J Bacteriol, 1982 Nov, 152(2), 706 - 13
Control of nitrogenase in a photosynthetic autotrophic bacterium, Ectothiorhodospira sp; Bognar A et al.; An Ectothiorhodospira species fixed nitrogen when grown as an autotroph in completely inorganic medium by using a variety of electron donors . The organism also used organic carbon sources; however, this required induction of synthesis of various enzymes, whereas the enzymes needed for autotrophic growth were synthesized constitutively . Nitrogenase induction and function were inhibited by ammonium chloride . Nitrogenase activity was dependent on light and inhibited by oxygen.

Ann Microbiol (Paris), 1982 Nov-Dec, 133(3), 351 - 63
{Purification and partial characterization of an extracellular aminopeptidase of a collagenolytic bacterium: Empedobacter collagenolyticum}; Montel MC et al.; An aminopeptidase was purified from the culture filtrates of a collagenolytic bacterium Empedobacter collagenolyticum . Purification of this enzyme was accomplished by ammonium sulphate precipitation, gel filtration on Sephadex-G200 and chromatography on DEAE-Sephacel . The purified enzyme seemed homogeneous on polyacrylamide gel electrophoresis . The molecular weight of the enzyme was about 100,000 daltons as determined by gel filtration on Sephadex-G200 but it was only 33,000 daltons by disc gel electrophoresis in the presence of sodium dodecyl sulphate . This enzyme selectively hydrolysed N-terminal arginine and lysine residues of peptides and arylamides substrates . The enzyme was strongly inhibited by EDTA, ZnCl2 and L-arginine.

Biochem J, 1982 Nov 1, 207(2), 241 - 52
Mechanistic studies on the dehydrogenases of methylotrophic bacteria . 2 . Kinetic studies on the intramolecular electron transfer in trimethylamine and dimethylamine dehydrogenase; Steenkamp DJ et al.; E.p.r . spectroscopy of the trimethylamine and dimethylamine dehydrogenases of Hyphomicrobium X indicates that the substrate-reduced forms of these enzymes exist in the triplet state, which arise through interaction of a reduced {4Fe-4S} cluster and flavosemiquinone, with e.p.r . signals which differ in detail from those of the trimethylamine dehydrogenase of bacterium W3A1 . Under certain conditions the intramolecular electron transfer between the flavoquinol form of 6-S-cysteinyl-FMN and the {4Fe-4S} cluster in all three dehydrogenases was much slower than the preceding reduction of the flavin to the flavoquinol form . Trimethylamine dehydrogenases from both organisms show a time-dependent broadening of the e.p.r . signals centred around g = 2 after mixing with trimethylamine . The broadening of the e.p.r . signals could be correlated with an unexpected dependence of the rate of formation of the triplet state on substrate concentration . A model which accounts in a qualitative manner for the substrate dependence of the formation of the triplet state in the trimethylamine dehydrogenase of Hyphomicrobium X is proposed . The binding of the substrate to the reduced form of the enzyme seems to result in a conformational change of the enzyme to a form in which the rate of intramolecular electron transfer is decreased . This finding may be correlated with the observation of hyperbolic substrate inhibition for both trimethylamine dehydrogenases . The results indicate the transfer of an electron to the {4Fe-4S} cluster to be an obligatory step in catalysis and suggest that the transfer of electrons from these enzymes to electron acceptors is mediated solely through the {4Fe-4S} cluster.

Biochem J, 1982 Nov 1, 207(2), 233 - 9
Mechanistic studies on the dehydrogenases of methylotrophic bacteria . 1 . The influence of substrate binding to reduced trimethylamine dehydrogenase on the intramolecular electron transfer between its prosthetic groups; Steenkamp DJ et al.; The trimethylamine dehydrogenase of bacterium W3A1 is reduced with the formation of a triplet state in which two electrons, derived from the substrate, are distributed between the {4Fe-4S} cluster and 6-S-cysteinyl-FMN semiquinone . In titration experiments at pH 8.5 about 1.0 mol of dimethylamine or 0.5 mol of trimethylamine per mol of the enzyme is required to titrate the enzyme to an endpoint . At pH values less than 8.0, however, an excess of trimethylamine is required to obtain maximal yield of the g = 4 e.p.r . signal, characteristic of the triplet state, or maximal absorbance at 365 nm which indicates formation of the flavin semiquinone . The binding of 0.86 mol of trimethylamine per mol of the enzyme could be detected by a gel chromatographic method . When the enzyme is titrated with dithionite in the presence of tetramethylammonium chloride, an endpoint is reached after the uptake of two electrons which give rise to the triplet state, whereas three electrons are consumed in the absence of tetramethylammonium chloride to reduce the enzyme completely . The enzyme is inhibited noncompetitively by tetramethylammonium chloride and the slopes of double reciprocal plots are a concave upwards function of inhibitor concentration . The data indicate the presence of a binding site for the substrate and other amines on the reduced enzyme which enhances the proportion of enzyme in the triplet state.

J Bacteriol, 1982 Nov, 152(2), 924 - 7
Expression of the transposable lac operon Tn951 in Rhodopseudomonas sphaeroides; Nano FE et al.; The transposon Tn951 (lac) was introduced into the photosynthetic bacterium Rhodopseudomonas sphaeroides 2.4.1, which is normally Lac-, via the P-group plasmid RP1 . beta-Galactosidase was produced constitutively in both chemotrophically and phototrophically grown cells, and the levels were found to be the same but low . Mutants were isolated, however, that were able to grow on lactose minimal medium and which expressed different levels of beta-galactosidase when grown chemotrophically or phototrophically . The beta-galactosidase levels found in all R . sphaeroides strains were much less than those found in Escherichia coli.

Eur J Biochem, 1982 Oct, 127(2), 423 - 8
Purification and characterization of acetoacetyl-CoA synthetase from Zoogloea ramigera I-16-M; Fukui T et al.; Acetoacetyl-CoA synthetase was purified to electrophoretic homogeneity from Zoogloea ramigera I-16-M, a poly(3-hydroxybutyrate)-accumulating bacterium, which lacks 3-ketoacid CoA-transferase . The purified enzyme had a specific activity of 52.2 mumol acetoacetyl-CoA formed min-1 mg protein-1, which constituted a 680-fold purification compared to the crude extract, with a 5.1% yield . The enzyme absolutely required ATP, CoA, a monovalent cation (K+, Rb+, Cs+ or NH+4) and a divalent cation (Mg2+, Mn2+, Ca2+ or Ni2+) for the activation of acetoacetate, yielding acetoacetyl-CoA, AMP and pyrophosphate in equimolar amounts . The pH optimum of the enzyme reaction was 8.4 . The molecular weight of the enzyme was approximately 70 000 as estimated by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate, and 72 000 by Sephadex G-200 gel filtration . The enzyme was active only on acetoacetate and to a lesser extent on L(+)-3-hydroxybutyrate, and the Km values for acetoacetate, L(+)-3-hydroxybutyrate, ATP and CoA were 7.6 X 10(-5) M, 1.4 X 10(-3) M, 3.3 X 10(-5) M and 9.1 X 10(-5) M respectively.

J Bacteriol, 1982 Oct, 152(1), 495 - 501
Trail following by gliding bacteria; Burchard RP; Slime trails, which are deposited on surfaces by gliding bacteria and which serve as preferential pathways for gliding motility, were tested for the species specificity of their support of movement . Among the pairs of bacteria tested, a variety of gliding bacteria and a flagellated bacterium moved along trails of unrelated species . Thus, the trails did not serve as pheromones . Rather, they may have guided gliding elasticotactically . Some biological implications of this finding are considered.

J Cell Biol, 1982 Oct, 95(1), 179 - 88
Topography of reaction center subunits in the membrane of the photosynthetic bacterium, rhodopseudomonas sphaeroides; Valkirs GE et al.; The localization of the reaction center polypeptides (L, M, and H) in the membranes of both the wild-type, strain 2.4.1, and the carotenoidless mutant, R-26, of Rhodopseudomonas sphaeroides was determined by using affinity-purified antibodies specific for these proteins . Binding of the antibodies to reaction center subunits in spheroplasts was visualized in the electron microscope by immunoferritin labeling . The H and M subunits were labeled at both the cytoplasmic and the periplasmic surfaces of the membrane, whereas the L subunit was labeled only at the periplasmic surface of the membrane . Thus, the reaction center is asymmetrically oriented in the membrane with at least two subunits (H and M) spanning the membrane.

Arch Microbiol, 1982 Oct, 132(4), 308 - 12
Effects of pantolactone and butyrolactone on the pleiotropic phenotypes of lon mutants and on thermal induction of the SOS phenomena in a tif mutant of Escherichia coli K12; Nakayama H et al.; Pantolactone and butyrolactone, known to suppress cell filament formation in the lon mutant of Escherichia coli, were found also to be capable of partially correcting other anomalies of the mutant including impaired lysogenization with bacteriophages lambda and Pl and increased synthesis of colanic acid . In contrast to pantolactone, which inhibited thermal induction of cell filament formation and lambda prophage in the tif mutant as previously described, butyrolactone enhanced these phenomena . It was inferred that whereas these substances exert their effects through acting upon the tif-recA protein in the tif bacterium, there is a distinct target for their characteristic actions in the lon mutant.

Science, 1982 Sep 3, 217(4563), 948 - 50
Phagocyte impotence caused by an invasive bacterial adenylate cyclase; Confer DL et al.; For unknown reasons, humans infected with the bacterium Bordetella pertussis are exceptionally vulnerable to secondary infections . Bordetella species elaborate a soluble, heat-stable, and highly active adenylate cyclase . This enzyme is internalized by phagocytic cells and catalyzes the unregulated formation of adenosine 3',5'-monophosphate (cyclic AMP), thereby disrupting normal cellular function . This unusual phenomenon may explain Bordetella-induced aphylaxis and may prove to be useful for investigating a variety of cyclic AMP-governed processes.

J Clin Microbiol, 1982 Sep, 16(3), 536 - 41
Pneumonia caused by a previously undescribed bacterium; Hopfer RL et al.; A new and as yet unidentified bacterium was isolated from the lung tissue of a cancer patient with bilateral pneumonia . Clinically, the pneumonia was consistent with legionellosis; the organism cultured from the lung grew only on the charcoal-yeast extract agar routinely used for Legionella isolation . Subsequent testing, however, showed the organism to be quite distinct from the known Legionella species in its biochemical, antigenic, and growth characteristics.

J Bacteriol, 1982 Sep, 151(3), 1269 - 78
Synthesis and utilization of fatty acids by wild-type and fatty acid auxotrophs of Caulobacter crescentus; Letts V et al.; The fatty acid composition of the dimorphic bacterium Caulobacter crescentus was found to consist primarily of 16- and 18-carbon fatty acids, both saturated and monounsaturated, in agreement with the findings of Chow and Schmidt (J . Gen . Microbiol . 83:359-373, 1974) . In addition, two minor but as yet unidentified fatty acids were detected . Chromatographic mobilities suggested that these fatty acids may be a cyclopropane and a branched-chain fatty acid . In addition, we demonstrated that the fatty acid composition of wild-type C . crescentus can be altered by growing the cells in medium supplemented with any one of a variety of unsaturated fatty acids . Linoleic acid, a diunsaturated fatty acid which is not synthesized by C . crescentus, was incorporated into phospholipids without apparent modification . In addition, we found that C . crescentus, like Escherichia coli, synthesizes vaccenic acid (18:1 delta 11,cis) rather than oleic acid (18:1 delta 9,cis) . This result allowed us to deduce that the mechanism of fatty acid desaturation in C . crescentus is anaerobic, as it is in E . coli . Finally, we examined the fatty acid biosynthesis and composition of two unsaturated fatty acid auxotrophs of C . crescentus . Neither of these mutants resembled the E . coli unsaturated fatty acid auxotrophs, which have defined enzymatic lesions in fatty acid biosynthesis . Rather, the mutants appeared to have defects relating to the complex coordination of membrane biogenesis and cell cycle events in C . crescentus.

Biochemistry, 1982 Aug 3, 21(16), 3842 - 9
Amino-terminal sequences of the L, M, and H subunits of reaction centers from the photosynthetic bacterium Rhodopseudomonas sphaeroides R-26; Sutton MR et al.; We have determined the sequence of the 25-28 amino-terminal residues of the three subunits, L, M, and H, of the membrane-bound reaction center protein of the photosynthetic bacterium Rhodopseudomonas sphaeroides R-26 . The sequences are as follows: L, H2N-Ala-Leu-Leu-Ser-Phe-Glu-Arg-Lys-Tyr-Arg- Val-Pro-Gly-Gly-Thr-Leu-Val-Gly-Gly-Asn-Leu-Phe-Asp-Phe-(His)-Val-; M, H2N-Ala-Glu-Tyr-Gln-Asn-Ile-Phe-Ser-Gln-Val-Gln-Val-Arg-Gly-Pro-Ala-Asp-Leu-Gly-Met-Thr-Glu-Asp-Val-Asn-Leu-Ala-Asn-; H, H2N-Met-Val-Gly-Val-Thr-Ala-Phe-Gly-Asn-Phe-Asp-Leu-Ala-Ser-Leu-Ala-Ile-Tyr-Ser-Phe-Trp-Ile-Phe-Leu-Ala-X-Leu-Ile- . The H sequence, especially after the aspartyl residue at position 11, is rich in hydrophobic residues, consistent with the possibility that this section of the polypeptide chain is located within the membrane . The L sequence is hydrophilic near the amino terminus and then becomes moderately hydrophobic . The M sequence is of average polarity.

J Bacteriol, 1982 Aug, 151(2), 534 - 41
Wavelength dependence of energy transduction in Rhodopseudomonas sphaeroides: action spectrum of growth; Hellingwerf KJ et al.; We determined the wavelength dependence of the specific growth rate of Rhodopseudomonas sphaeroides (the action spectrum of growth) . A half-maximal (light-limited) growth rate was obtained when the culture vessel was illuminated with photon intensities between 0.8 x 10(14) and 3.5 x 10(14) photons cm-2 s-1 in the wavelength region between 400 and 950 nm . In the action spectrum, measured at 1.25 x 10(14) photons cm-2 s-1, distinct peaks could be observed at 480, 580, 800, and 870 nm, and minima could be found at 420, 540, 640 to 730, 830, and 940 nm . Both the pigment content and pigment composition of R . sphaeroides varied, depending on the wavelengths of the actinic light used for growth . This demonstrates that chromatic adaptation occurs in this bacterium.

Int J Radiat Biol Relat Stud Phys Chem Med, 1982 Aug, 42(2), 141 - 9
Correlation of bacterial hyperthermic survival with anaesthetic potency; Yatvin MB et al.; We have evaluated several local anaesthetics and hypnotics for their relative ability to influence hyperthermic cell killing . Bacterial cell survival following exposure to heat and anaesthetic was used as the assay system . The E . coli bacterium used was the unsaturated fatty acid auxotroph, K1060 . It was grown at 37 degrees C in medium supplemented with oleic acid and then exposed to 47 degrees C hyperthermia in the presence of an anaesthetic . The local anaesthetics tested were procaine, lidocaine, tetracaine, and benzocaine, and the general anaesthetics were barbital and pentobarbital . The dose response for each anaesthetic was determined over a five-hour heating period . The anaesthetic concentration required during heating to halve the time for cell killing found with heat alone is 5.9 mM for procaine, 0.8 mM for lidocaine, 0.12 mM for tetracaine, 2.0 mM for benzocaine, 6.7 mM for barbital and 1.2 mM for pentobarbital . There is a direct correlation between equivalent effect doses of the local anaesthetics and published data for the relative potency of the same anaesthetics as determined by respiratory arrest in mice and by myocardial contractile force in dogs . The assay we have described would be a convenient and easy test for the interaction of these drugs with hyperthermia . The use of this interaction with hyperthermia as an adjuvant in combined radiation-hyperthermia therapy should be tested.

Surgery, 1982 Aug, 92(2), 138 - 45
Prospects for the control of host defenses; Howard RJ; Systemic host defenses include phagocytic cells (neutrophils and macrophages), humoral immunity, and cell-mediated immunity . It may be beneficial to increase host defenses to prevent and treat infections, cancer, and often acquired or systemic immunodeficiency disorders . On the other hand, inhibition of immune responsiveness is desirable to prevent and treat rejection of organ grafts, allergic reactions, and autoimmune diseases . There are three general ways to modulate host defenses--pharmacologic agents, radiation, and biologic manipulation . The first two have been most widely applied but lack specificity . Thus, they generally inhibit a variety of immune responses that can lead to undesirable side effects such as infections and cancer . Nonspecificity is generally desirable in stimulating neutrophils and macrophages because it may not be known which bacterium is causing the infection or because several may be involved . Biologic manipulations have the advantage of great specificity but are much more difficult to apply to humans . Some of these types of manipulations that seem to hold promise are stimulators of phagocytosis, immunologic tolerance, control of specific subsets of T lymphocytes, monoclonal antibodies, and interferon . Immune modulation has a price-cancer, susceptibility to infection, toxicity of drugs, serum sickness, anaphylactic reactions, Arthus reaction, and disseminated infection with live viral vaccines.

Ann Intern Med, 1982 Jul, 97(1), 51 - 5
Chronic granulomatous disease of childhood and Chromobacterium violaceum infections in the southeastern United States; Macher AM et al.; Patients with chronic granulomatous disease are predisposed to infections by catalase-positive organisms in the environment . Chromobacterium violaceum is a catalase-positive bacterium whose saprophytic source in this country is the subtropical soil and water of the southeastern United States . Two patients with chronic granulomatous disease, followed at the National Institutes of Health in Maryland, acquired C . violaceum infections in Florida . All 10 cases previously reported were acquired in Florida and Louisiana, and reports for which dates were available showed that all infections were acquired from June to September . Seven of 10 patients died; one patient was studied and found to have chronic granulomatous disease . Thus, at least three of the 12 known patients have had underlying chronic granulomatous disease . We suggest that C . violaceum infections occur with unusual frequency in patients with a common underlying predisposing disorder; C . violaceum poses a potential threat to patients with chronic granulomatous disease living in or visiting the endemic states.

Mol Biol (Mosk), 1982 Jul-Aug, 16(4), 830 - 6
{Study of ferredoxins in membranes of Rhodopseudomonas spheroides by means of Mossbauer spectroscopy}; Uspenskaia NIa et al.; Mossbauer spectra were investigated in membranes (chromatophores) of Rhodopseudomonas sphaeroides, enriched in 57Fe, over a temperature range from 4.2 to 300 K . The spectrum of isolated chromatophores is a symmetric doublet characterized by an isomeric shift delta=0.60+/-0.03 mm/s, quadrupole splitting delta=0.54+/-0.03 mm/s and a width gamma delta of 1.42+/-0.04 mm/3 at half maximum . These parameters, which are in fact characteristic of the Mossbauer spectra of bacterial ferredoxins, appeared practically invariable over a wide range of temperatures . The spectrum of dithionite-treated chromatophores, measured immediately after dithionite treatment, exhibits, in addition, a doublet having parameters characteristic of high-spin bivalent iron . The doublet linewidth of the Fe2+ (S=2) iron is equal, at room temperature, to the emission spectrum linewidth . At 4K, some broadening of the spectrum is observed, which is of magnetic origin . The intensity of the Fe2+(S=2) doublet from a dithionite-treated sample shows a pronounced drop after several days of storage, with the intensity of the initial doublet rising . The overall area under the spectra, the linewidth and shape are not changed . Based on experimental data obtained, possible models of the active center composed of most frequently encountered membrane-bound ferredoxins of the photosynthetic bacterium Rhodopseudomonas sphaeroides are discussed.

Mikrobiologiia, 1982 Jul-Aug, 51(4), 557 - 9
{Biosynthetic incorporation of fluorescently labelled fatty acids in Escherichia coli}; Tsukerman AI et al.; Escherichia coli cells were cultivated in a medium containing 1-pyrene butanoic acid, a fluorescent probe . Total lipids were extracted from the cells, and the extract was separated by thin-layer chromatography . The fluorescent fractions were examined using spectrofluorimetry . The starting 1-pyrene butanoic acid was shown to be biosynthetically incorporated into the bacterial lipid . Four fluorescent fractions appeared as a result; the fractions were derivatives of this compound modified in the chromophore and the fatty acid chain . The results indicate that the formation of 1-pyrene butanoic acid fluorescent metabolites can be used for studying the oxidation-reduction systems of the bacterium.

Biokhimiia, 1982 Jul, 47(7), 1118 - 24
{Role of CO-binding cytochrome c in enzymatic oxidation of methane by the bacterium Methylococcus capsulatus}; Gvozdev RI et al.; The cytochrome c spectrally related to cco cytochromes has been isolated and purified from the methane-oxidizing bacterium Methylococcus capsulatus . The cytochrome binds CO but does not bind other substrates of methane monooxygenase, does not activate the methane monooxygenase reaction and is not a component of methane monooxygenase . In the methanol dehydrogenase enzymatic system cytochrome cco functions as electron acceptor . A possible role of cytochrome cco as electron carrier intermediate in the sequence of the dehydrogenase and oxidase enzymatic systems of M . capsulatus is discussed.

J Bacteriol, 1982 Jun, 150(3), 1322 - 8
Efficiency of light-driven metabolite transport in the photosynthetic bacterium Rhodospirillum rubrum; Zebrower M et al.; An evaluation of the efficiency of the L-alanine and L-malate transport systems was undertaken with the photosynthetic bacterium Rhodospirillum rubrum grown on the amino acid whose uptake was measured . An all-glass apparatus was constructed for measuring transport activity under anaerobic conditions . L-Alanine transport activity decreased under conditions of Mg2+ depletion . When cells were allowed to become inactive by suspending them in the dark in Mg2+-free buffer, full activity could be restored with a few minutes by adding 20 mM Mg2+ and illuminating the cells . The transport activity was completely inhibited by carbonyl cyanide m-trifluoromethoxyphenylhydrazone and by ammonia . The quantum yield for the uptake of either L-alanine or L-malate was 0.015 molecules per photon . The results are discussed in relation to the expected efficiencies for metabolite transport and regulation by Mg2+.

J Bacteriol, 1982 Jun, 150(3), 1109 - 14
Glucose transport system in a facultative iron-oxidizing bacterium, Thiobacillus ferrooxidans; Sugio T et al.; Properties of a heat-labile glucose transport system in Thiobacillus ferrooxidans strain AP-44 were investigated with iron-grown cells . {14C}glucose was incorporated into cell fractions, and the cells metabolized {14C}glucose to 14CO2 . Amytal, rotenone, cyanide, azide, 2,4-dinitrophenol, and dicyclohexylcarbodiimide strongly inhibited {14C}glucose uptake activity, suggesting the presence of an energy-dependent glucose transport system in T . ferrooxidans . Heavy metals, such as mercury, silver, uranium, and molybdate, markedly inhibited the transport activity at 1 mM . When grown on mixotrophic medium, the bacteria preferentially utilized ferrous iron as an energy source . When iron was exhausted, the cells used glucose if the concentration of ferrous sulfate in the medium was higher than 3% (wt/vol) . However, when ferrous sulfate was lower than 1%, both of the energy sources were consumed simultaneously.

Vet Rec, 1982 May 22, 110(21), 488 - 94
Immunisation of pigs against experimental infection with Bordetella bronchiseptica; Smith IM et al.; During pregnancy seven minimum-disease sows (group A) were infected intranasally with Bordetella bronchiseptica, fed with the killed bacterium periodically and inoculated parenterally with a dead vaccine eight, six and two weeks before parturition . Groups B and C, isolated from A until farrowing, contained respectively six sows given the vaccine parenterally and eight control sows . At parturition, group A had much higher average agglutinin titres in the serum and colostrum than B or C . Group A sows gave their piglets a better passive protection against infection with B bronchiseptica strain 293 and its effects in the respiratory tract during the first eight weeks of life, especially in those exposed to spontaneous infection with bordetellae from a littermate deliberately inoculated intranasally 24 hours after birth . Passive antibody strongly affected the capacity of piglets to respond actively to parenteral vaccination (when seven and 28 days old), marked humoral responses being noted only in those from group C sows . Vaccination of piglets exposed to infection by contact reduced neither the prevalence or intensity of the nasal infection, the amount of turbinate atrophy or pneumonia nor significantly improved weight gain compared with unvaccinated littermates . Unlike their eight-week-old littermates there was little hypoplasia and no pneumonia in infected pigs (whether vaccinated or not) when they reached five months of age.

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