Cancer Surv, 1989, 8(4), 713 - 23 Bacteria and cancer--antagonisms and benefits; Nauts HC; There is considerable historical and recent evidence concerning the antagonisms between acute bacterial infections or their toxins and cancer and allied diseases . These data provide renewed incentives to undertake clinical programmes with mixed bacterial vaccines in many countries at the present time. Genome, 1989, 31(2), 864 - 9 Evolutionary principles and the regulation of engineered bacteria; Davis BD; The introduction of engineered bacteria to the environment is being overregulated, on the basis of several assumptions: (i) the danger from deliberate introduction on a large scale is much greater than that from accidental release; (ii) the more distant the source of the DNA the greater the risk; (iii) novel organisms are likely to cause unexpected ecological damage, like that seen with native organisms transplanted to a novel location; (iv) even if the probability of harm is very small, great care must be taken because the harm might be large; (v) products of recombinant DNA must be treated differently from products of classical genetic manipulation; and (vi) our unlimited power to manipulate DNA implies an unlimited power to refashion organisms . Evolutionary principles contradict all these assumptions . Moreover, our increased power of genetic manipulation must be recognized as an expansion of the biotechnology of domestication; and unlike the physical technologies, the long history of domestication has not adventitiously created harmful by-products . I propose that in dealing with such novel and unpredictable developments it would be better to respond with speed and resilience to problems as they arise, rather than to hamper advances by clumsy regulations based on unsubstantiated guesses. Arch Exp Veterinarmed, 1989 Jan, 43(1), 129 - 36 {Infection studies in laboratory mice with erysipelas and coli bacteria after the administration of biotechnical substances}; Lusky K et al.; Chlormadinone-acetate, human chorionic gonadotrophin, oestrophan, and zinc-metallibur, all of them substances used for biotechnological indications, were tested in generation experiments for their bearings on the immune status . The tests were applied to untreated descendants of biotechnologically treated mothers . Though the model animal experiments were continued through 6 generations of laboratory mice, no clue was obtained as to immunosuppressive action of any of the substances involved. J Appl Bacteriol, 1989 Jan, 66(1), 49 - 55 Investigation of a simple amperometric electrode system to rapidly quantify and detect bacteria in foods; Patchett RA et al.; A two electrode system mounted as a single probe was developed to measure electrochemically the rate of reduction of a redox mediator (thionine) by bacteria . The system gave a rapid (2 min) bacterial-dependent current above 2.5 x 10(5) cfu/ml with pure cultures of bacteria, but when applied to the measurement of the bacterial contamination in samples of meat and milk it was unable to detect or quantify the contamination reliably . Incubation of samples for a few hours before examination enabled the system to detect bacteria in excess of 10(6) cfu/ml. Mutat Res, 1989 Jan, 217(1), 33 - 8 Evidence that ultraviolet light-induced DNA replication death of recA bacteria is prevented by protein synthesis in repair-proficient bacteria; Doudney CO et al.; The ultraviolet light (UV) survival curve of Escherichia coli WP10 recA trp is almost biphasic, with a greatly reduced shoulder but demonstrating a transition to a decreased slope with increasing fluences, indicating the presence in the culture of a low frequency of resistant cells . Treatment of the culture with chloramphenicol before UV exposure brought almost all of the cells to a high degree of UV resistance, by bringing them to the end of their DNA replication cycle . The survival curves of the repair-proficient E . coli WP2 trp showed a similar pattern with chloramphenicol treatment or tryptophan starvation before UV exposure, but only if protein synthesis were blocked by chloramphenicol for 60 min after UV exposure . The results suggest that when recA/lexA-regulon induction is prevented, either by the recA mutation or by inhibition of protein synthesis after UV exposure, death occurs unless the cells are in the resistant state characteristic of bacteria at the end of their DNA replication cycle . With repair-proficient bacteria treated before UV exposure with chloramphenicol, when protein synthesis is not blocked after UV exposure, a marked expansion of the shoulder occurs because of the function of another resistance-conferring mechanism . This mechanism also depends on the recA+ gene since expansion of the shoulder does not occur in recA bacteria when protein synthesis is inhibited before UV exposure. Gastroenterology, 1989 Jan, 96(1), 86 - 94 Adherence of bacteria to the intestine in sporadic cases of enteropathogenic Escherichia coli-associated diarrhea in infants and young children: a prospective study; Sherman P et al.; Intimate adherence of bacteria to duodenal enterocytes was demonstrated in a 12-mo-old child with sporadic diarrhea that was associated with an enteropathogenic Escherichia coli (EPEC) of the serogroup O111:K58 . Therefore, a prospective study was initiated to determine if identification of EPEC in stools from sporadic cases of diarrhea of longer than 10 days in duration in children under 24 mo of age correlated with E . coli colonization of the proximal small intestine and with binding of bacteria to intestinal epithelial cells . Colonization was determined by culture of duodenal aspirates and enteroadherence by light- and electron-microscopic evaluation of both duodenal and rectal mucosa . Each EPEC isolate was examined for several previously proposed laboratory markers of virulence including alpha-hemolysin production, agglutination of erythrocytes, cell surface hydrophobicity properties, adherence to HEp-2 cells, and Verotoxin production . Ten sporadic cases of EPEC-associated diarrhea, severe enough to require hospitalization in each instance, were present among 105 patients in whom EPEC were identified in stools . Of the 10 cases, 9 were evaluated in more detail . In contrast to the first case, in the prospective study E . coli were cultured from duodenal aspirates in only 1 patient and enteroadherent organisms were not present on careful review of small bowel (0/9) and rectal (0/7) mucosa . Hemolysin production (9 of 10 EPEC strains), mannose-sensitive hemagglutination (7/10), hydrophobic cell surface properties (0/10), adherence to HEp-2 cells (7/10), and production of Verotoxin (0/10) did not distinguish the one enteroadherent EPEC from the nine EPEC strains in which in vivo enteroadherence was not documented . In this study of sporadic cases of EPEC-associated diarrhea in young children, bacterial colonization of the small bowel and enteroadherence in vivo could not routinely be demonstrated . In addition, those laboratory assays of bacterial virulence that were evaluated did not distinguish the adherent strain from nonadherent EPEC strains. Enferm Infecc Microbiol Clin, 1989 Jan, 7(1), 36 - 9 {Antibody-coated bacteria in the sputum from patients with pneumococcal pneumonia}; Sala-Mateus C et al.; In the present study an immunofluorescence technique detecting antibody-coated bacteria was evaluated . It was applied to the sputum of seven patients with bacteremic pneumococcal pneumonia to assess its diagnostic usefulness . We conclude that it is a valid, quick and easy technique which permits to differentiate between bacteria contaminating the sputum from those involved in the infection . This gives, therefore, a new value to the study of sputum . In our series the duration of the disease had no influence on the results, and the three antigammaglobulins used (anti-IgG, anti-IgA and anti-IgM) yielded the same results in each sample . Thus, we feel that the local pulmonary immune response was secondary in type. Lab Delo, 1989, (2), 61 - 3 {A method of determining the catalase activity of bacteria}; Varvashevich TN et al.; An iodine-starch method has been developed for the detection of catalase in bacteria and for measuring this enzyme's activity . The method is based on potassium iodide reduction with hydrogen peroxide to form free iodine . The bacteria are layered on starch gel, treated with hydrogen peroxide, and then with potassium iodide . The starch gel stains blue, and light areas emerge round catalase-positive bacteria; the size of these light sites helps assess the enzyme's activity . The method permits estimating the populational heterogeneity of the cultures judging from catalase activities and helps detect the mutants by catalase; it is convenient, simple, and provides reliable information on the taxonomic status of the bacteria. Cytometry, 1989 Jan, 10(1), 70 - 6 Characterizing aquatic bacteria according to population, cell size, and apparent DNA content by flow cytometry; Robertson BR et al.; Flow cytometry offers a rapid method for characterizing aquatic populations according to the properties of individual cells . This technology has been extended to aquatic bacteria by using high-intensity UV excitation, condensing the laser beam onto a small area, using blemish-free flow cells, optimizing organism staining protocol, segregating the optical signal produced with high-transmittance optical filters, collecting the signal with sensitive photomultipliers, and expanding the range of data displayed from individual samples with calibrated circuitry . Bacteria could be counted according to event frequency, and populations agreed with direct counts by epifluorescence microscopy . Forward scatter intensity was a linear function of volume for bacterial cells between 1.3 and 0.25 micron 3 as calibrated by Coulter impedance . Plastic spheres down to 0.014 micron 3, 0.3 micron in diameter, were resolved . Aquatic bacteria 0.05 micron 3 in volume were clearly resolved according to DNA content by staining with DAPI . The observed signal was DNA-dependent because DNase treatment eliminated most fluorescence . These procedures are suitable for direct analysis of the bacteria in marine and freshwater samples without interference from algae, sediment, or most DNA-free organic particles . Cytograms indicated one or more clearly resolved subpopulations of bacteria of substantially smaller size and DNA content than the laboratory organisms typically classified. J Theor Biol, 1988 Dec 7, 135(3), 309 - 21 Spatial dependence of stress distribution for rod-shaped bacteria; Chatterjee AP et al.; The stress distribution in the cylindrical portion of the cell envelope of a rod-shaped bacterial cell was compared with that at its polar ends . Using a symmetry argument it is shown that the critical internal pressure for the initiation of yielding of the envelope material has a non-uniform distribution and is significantly higher for the polar regions. FEMS Microbiol Rev, 1988 Dec, 4(4), 299 - 344 The three classes of hydrogenases from sulfate-reducing bacteria of the genus Desulfovibrio; Fauque G et al.; Three types of hydrogenases have been isolated from the sulfate-reducing bacteria of the genus Desulfovibrio . They differ in their subunit and metal compositions, physico-chemical characteristics, amino acid sequences, immunological reactivities, gene structures and their catalytic properties . Broadly, the hydrogenases can be considered as 'iron only' hydrogenases and nickel-containing hydrogenases . The iron-sulfur-containing hydrogenase ({Fe} hydrogenase) contains two ferredoxin-type (4Fe-4S) clusters and an atypical iron-sulfur center believed to be involved in the activation of H2 . The {Fe} hydrogenase has the highest specific activity in the evolution and consumption of hydrogen and in the proton-deuterium exchange reaction and this enzyme is the most sensitive to CO and NO2- . It is not present in all species of Desulfovibrio . The nickel-(iron-sulfur)-containing hydrogenases {( NiFe} hydrogenases) possess two (4Fe-4S) centers and one (3Fe-xS) cluster in addition to nickel and have been found in all species of Desulfovibrio so far investigated . The redox active nickel is ligated by at least two cysteinyl thiolate residues and the {NiFe} hydrogenases are particularly resistant to inhibitors such as CO and NO2- . The genes encoding the large and small subunits of a periplasmic and a membrane-bound species of the {NiFe} hydrogenase have been cloned in Escherichia (E.) coli and sequenced . Their derived amino acid sequences exhibit a high degree of homology (70%); however, they show no obvious metal-binding sites or homology with the derived amino acid sequence of the {Fe} hydrogenase . The third class is represented by the nickel-(iron-sulfur)-selenium-containing hydrogenases {( NiFe-Se} hydrogenases) which contain nickel and selenium in equimolecular amounts plus (4Fe-4S) centers and are only found in some species of Desulfovibrio . The genes encoding the large and small subunits of the periplasmic hydrogenase from Desulfovibrio (D.) baculatus (DSM 1743) have been cloned in E . coli and sequenced . The derived amino acid sequence exhibits homology (40%) with the sequence of the {NiFe} hydrogenase and the carboxy-terminus of the gene for the large subunit contains a codon (TGA) for selenocysteine in a position homologous to a codon (TGC) for cysteine in the large subunit of the {NiFe} hydrogenase . EXAFS and EPR studies with the 77Se-enriched D . baculatus hydrogenase indicate that selenium is a ligand to nickel and suggest that the redox active nickel is ligated by at least two cysteinyl thiolate and one selenocysteine selenolate residues.(ABSTRACT TRUNCATED AT 400 WORDS) Mutat Res, 1988 Dec, 202(2), 387 - 91 Antimutagenesis by factors affecting DNA repair in bacteria; Kuroda Y et al.; The term 'antimutagen' was originally used to describe an agent that reduces the apparent yield of spontaneous and/or induced mutations, regardless of the mechanisms involved . The 'antimutagens' include 'desmutagens' and 'bio-antimutagens' . In this article, our attention was focused on the bio-antimutagens affecting DNA repair in bacteria . Cobaltous chloride reduced the frequency of mutations in Escherichia coli induced by MNNG . The possibility that metal compound inhibits the growth of mutagen-treated cells was examined . The results clearly showed that the antimutagen surely reduces the mutation rate . The target of cobaltous chloride was found to be cellular factors including Rec A . Vanillin and cinnamaldehyde had strong antimutagenic activities against UV, 4NQO and AF-2 . They stimulated Rec A-dependent recombination repair functions in the mutagen-treated cells . Among plant materials, tannins possess antimutagenic activity against UV-induced mutations in E . coli . It has been found that tannic acid stimulates the excision repair encoded by the uvrA gene thereby reducing the yield of mutants . Substances which are antimutagenic in bacterial systems also had antimutagenic activity in cultured mammalian cell systems . Vanillin reduced the frequency of mutagen-induced chromosomal aberrations. Appl Environ Microbiol, 1988 Dec, 54(12), 2949 - 52 Rapid and simple method for double staining of bacteria with 4',6-diamidino-2-phenylindole and fluorescein isothiocyanate-labeled antibodies; Hoff KA; Bacteria were either heat fixed on microscope slides or filtered with 0.2 micron-pore-size Nuclepore filters . The samples were stained with 4',6-diamidino-2-phenylindole (DAPI) for total staining and with polyvalent rabbit antibodies and fluorescein isothiocyanate-conjugated swine anti-rabbit antibodies for specific staining . By switching between two different optical filter packages in the microscope, only one sample was needed for determining both total and specific counts of bacteria . False-positive counts and other artifacts that occur with antibody staining were easily distinguished when individual fluorescent particles were checked for DAPI fluorescence . The method for applying the general stain to membrane filters was performed quickly and simply by using a DAPI-soaked polypropylene filter that lay beneath the Nuclepore filter which collected the sample. Biochem Biophys Res Commun, 1988 Nov 30, 157(1), 106 - 8 Reduction of nitrite to nitric oxide by enteric bacteria; Ji XB et al.; Seven bacteria representing seven genera of enteric bacteria, in addition to Escherichia coli, were shown to reduce nitrite to NO under anaerobic conditions when the cells were grown as nitrate respirers . NO production was inhibited by nitrate and azide and was self limiting, just as was found to be the case previously with E . coli and its nitrate reductase . Maximum initial rates of NO production were observed at pH 5.5-6. Comput Appl Biosci, 1988 Nov, 4(4), 431 - 3 Direct procedure for the determination of the number of replication forks and the reinitiation fraction in bacteria; Jimenez-Sanchez A et al.; A direct method for calculating the average number of replication forks per chromosome in an exponentially growing bacterial culture and the fraction of reinitiation after an inductive treatment of the initiation step is presented . This method has allowed the development of REPLICON, a computer program designed for the resolution of the algorithm and simulation of the bacterial chromosome replication . Using REPLICON the following parameters can be obtained: average number of replication forks per chromosome, time required for the complete replication cycle, average amount of DNA per nucleotide, gene frequency of any chromosomal locus and reinitiation fraction . The use of this analysis also permits the determination of the uni- or bidirectionality of replication. Microbiol Sci, 1988 Nov, 5(11), 340 - 3 Enumeration and identification of bacteria from environmental samples using nucleic acid probes; Hazen TC et al.; DNA probes are useful for both identification and enumeration of specific bacteria and functional groups of bacteria in environmental samples . Because probes can detect genes, chromosomes, and plasmids, they also promise to be major sources of information about the relatedness of bacteria and groups of bacteria in the environment. Mikrobiologiia, 1988 Nov-Dec, 57(6), 1046 - 8 {Membrane potential in Escherichia coli bacteria subjected to the action of low temperature freezing and blood serum complement}; Talybov ShT et al.; The action of a blood serum complement on Escherichia coli cells or their freezing does not cause cell destruction visible in the electron microscope, but the permeability barrier is disordered and exogenous substrates can penetrate into the cell . When these exogenous respiration substrates are oxidised, the energy-dependent uptake of phenyl dicarboundecarborane (PCB-), a lipophilic anion and an indicator of the membrane potential, is observed . Apparently, the uptake of PCB- is associated with the generation of local membrane potentials when the permeability barrier of cells is damaged. Mikrobiologiia, 1988 Nov-Dec, 57(6), 1007 - 10 {Damage photosensitized by chlorine e6 in bacteria with various defects of the DNA repair system}; Zorina TE et al.; The goal of the work was to study the sensitivity of isogenic Escherichia coli cells differing in their ability to mediate DNA repair steps to the action of visible light sensitized by chlorine e6 . Cells incapable of excision repair as well as those deficient in post-replicative recombination DNA repair were found to be much more sensitive to the combined action of visible light and chlorine e6 as compared to cells whose genes responsible for DNA repair were not damaged . The results indicate that visible light damages bacterial DNA in the presence of chlorine e6. Acta Otolaryngol, 1988 Nov-Dec, 106(5-6), 435 - 40 Quantification of bacteria in middle ear effusions; Stenfors LE et al.; Quantification of bacteria in various effusion materials (serous, sticky glue, mucopurulent and purulent) collected from 128 middle ears (96 patients) was performed . After sampling, the effusion material was immediately flushed onto a glass slide, stained with acridine orange and examined under a fluorescence microscope . Quantification of bacteria was performed as described . 93% of the serous (n = 28) and 61% of the sticky glue (n = 46) effusion materials contained no bacteria whatsoever . The infectious sticky glue material (n = 18) contained 2.0 x 10(5) (median value), mucopurulent effusion material (n = 24) 2.6 x 10(7) (median value) and purulent effusion (n = 30) 10(9) (median value) bacteria per ml effusion material . Direct microscopic examination of middle ear effusion material, including quantification of the bacteria involved, provides much information about the pathophysiology of the middle ear inflammation. Cell, 1988 Oct 21, 55(2), 281 - 90 Cloning and functional expression in bacteria of a novel glucose transporter present in liver, intestine, kidney, and beta-pancreatic islet cells; Thorens B et al.; The well-characterized erythrocyte glucose transporter is also expressed in brain, adipocytes, kidney, muscle, and certain transformed cells, but not in liver, intestine, or the islets of Langerhans . Using as probe a cDNA encoding the rat brain glucose transporter, we isolated from a rat liver cDNA library a clone encoding a protein 55% identical in sequence to the rat brain transporter, and with a superimpossible hydropathy plot . We expressed this protein in an E . coli mutant defective in glucose uptake; the protein was incorporated into the bacterial membrane and functioned as a glucose transporter . This new transporter is expressed in liver, intestine, kidney, and the islets of Langerhans; immunofluorescence analysis showed that it is present in the plasma membrane of the insulin-producing beta cells . Insulinoma cells express, inappropriately, the erythrocyte glucose transporter, and we suggest that this may be related to their inability to secrete insulin in response to elevations in glucose. J Theor Biol, 1988 Oct 7, 134(3), 341 - 50 A single calcium flux triggers chromosome replication, segregation and septation in bacteria: a model; Norris V et al.; Abrupt changes in the concentration of intracellular calcium, through the mediation of calmodulin, is presumed to play an essential role in many molecular processes in eukaryotes including triggering cell cycle events . Although early studies failed to establish any role for calcium in the growth of bacteria, recent studies have demonstrated that bacteria have several calcium transport systems, and an intracellular concentration of free calcium identical to that of higher organisms, which appears to fluctuate during the cell cycle . Moreover, calmodulin-like proteins have been reported in bacteria, and the growth of E . coli is sensitive to calmodulin inhibitors . In this article we propose that a single flux of calcium, abruptly raising the intracellular concentration of free calcium, is responsible for the triggering in bacteria of the major cell cycle events, initiation of DNA replication, chromosome partition and cell division . We predict that major roles in this process will involve a bacterial calmodulin-like protein and a primitive cytoskeleton . The mechanism of triggering different cell cycle events by a single calcium flux is discussed. J Bacteriol, 1988 Oct, 170(10), 4594 - 7 Structural diversity among methanofurans from different methanogenic bacteria; White RH; An examination of the methanofurans isolated from a wide range of methanogenic bacteria and from Archaeoglobus fulgidus has revealed at least five chromatographically distinct methanofurans . Bacteria from each major genus of methanogenic bacteria have been found to contain a chemically different methanofuran . The nature of the differences in the methanofurans appears to lie in the modification of the side chain attached to the basic core structure of 4-{N-(gamma-L-glutamyl-gamma-L-glutamyl)-p-(beta-aminoethyl)phenoxyme thy l}-2-(amino-methyl)furan . This was supported by the structural elucidation of the methanofuran isolated from Methanobrevibacter smithii, designated methanofuran-c, which was the same as the originally characterized methanofuran except for a hydroxy group at the 2 position of the 4,5-dicarboxyoctanedioic acid moiety of the molecule. Zh Mikrobiol Epidemiol Immunobiol, 1988 Oct, (10), 11 - 5 {A rapid and simple method for extracting intracellular metabolites from Escherichia coli bacteria}; Potselueva MM; The article deals with the development of a new method for the extraction of intracellular glycolytic metabolites from bacterial cells . The study has been made on the culture of E . coli B/r CSH . In accordance with this method, the same bacterial filter is used for both filtration (the removal of the culture fluid) and the extraction of low-molecular components of the cells with perchloric acid . The advantage of this method is the absence of unnecessary operations due to the use of a filter installation designed by the author . Quantitatively, this method yields better and reproducible results . The filtration capacity of different types of filters has been analyzed . The optimal time for the extraction of low-molecular cell components has been determined . A change in the concentration of pyruvate in the process of the cellular cycle of E . coli synchronous culture grown in the presence of glucose has been shown to occur . The newly developed method of extraction can be used not only for E . coli, but also for cells of other types. J Periodontol, 1988 Oct, 59(10), 688 - 96 In situ correlative immuno-identification of mononuclear infiltrates and invasive bacteria in diseased gingiva; Saglie FR et al.; The purpose of this study was to identify and quantify mononuclear cells and invasive bacteria in consecutive histological sections in diseased gingiva . Gingival biopsies were obtained from sites displaying evidences of severe periodontitis (pocket depth greater than 5 mm, bleeding on probing) in six patients . Specimens were frozen and serially sectioned at 8 micron in a cryostat . Monoclonal antibodies (mAb) directed against membrane markers of mononuclear infiltrate cells and rabbit polyclonal sera against specific bacteria shown to be invasive in association with an immunoperoxidase technique and specific point quantification were used . The mAb panel included Leu 1 (Pan T), Leu 2a (T suppressor/cytotoxic), Leu 3a (T helper/inducer), Leu 6 (Langerhans/dendritic), Leu 7 (NK/K), Leu M3 (monocyte/macrophage), and B7 (B cell) . This methodology allows for in situ per cent quantification of mononuclear cell subsets along with identification and quantification of invasive bacteria in the same gingival tissue site . This may be a practical approach to establish the relationship between bacterial invasion and cellular immune response by the host . This technique enabled the characterization of the mononuclear infiltrate in relationship to specifically identified invasive bacteria in diseased gingiva. Can J Microbiol, 1988 Sep, 34(9), 1099 - 102 Identification of rumen bacteria that anaerobically degrade nitrite; Cheng KJ et al.; Fifty-one pure strains of rumen bacteria, representing 15 genera, were tested for their ability to metabolize nitrite . Twenty-five of the strains, belonging to eight genera, were capable of growth and nitrite metabolism in nitrite-containing medium sterilized by autoclaving . An additional 10 strains showed growth and nitrite metabolism in medium that was autoclaved before the addition of filter-sterilized nitrite . Nitrite metabolism was not observed in the remaining 16 strains, and these were also incapable of growth in the presence of nitrite . Ammonia was produced during nitrite reduction by Megasphaera elsdenii J1 . In agreement with previous studies, abiotic losses of nitrite were observed during autoclaving and storage of media, but losses of nitrite due to bacterial metabolism were much greater. J Nat Prod, 1988 Sep-Oct, 51(5), 874 - 8 Metabolism of homoorientin by human intestinal bacteria; Hattori M et al.; As a part of our studies on the metabolism of bioactive compounds from oriental medicines by intestinal flora, homoorientin, a C-glycosylflavonoid, was anaerobically incubated with a human intestinal bacterial mixture . Homoorientin was transformed to 6-C-glucosyleriodictyol, (+/-)-eriodictyol, luteolin, 3,4-dihydroxyphenylpropionic acid, and phloroglucinol . A novel cleavage of the C-glycosyl bond was discovered for the first time by using intestinal bacteria. Anal Biochem, 1988 Sep, 173(2), 271 - 7 Use of a computer to assay motility in bacteria; Sager BM et al.; An assay was developed to study the movement of free-swimming Escherichia coli . Cells were videotaped through a microscope, and the videotape images were then digitized and analyzed with a computer . Angular and linear speeds were measured for wild-type E . coli and for a smooth and a tumbly mutant . The average angular and linear speeds of a population were directly and inversely proportional, respectively, to the time spent tumbling . Changes in angular and linear speeds were followed during the response of wild-type E . coli to attractant or repellent. Rev Infect Dis, 1988 Sep-Oct, 10(5), 958 - 79 Proposed mechanisms for the translocation of intestinal bacteria; Wells CL et al.; Members of the endogenous flora have become recognized as major pathogens in nosocomial infections, and the intestinal tract has become recognized as a major portal of entry for these pathogens . The English-language literature on this topic has been summarized and a working hypothesis devised describing a mechanism whereby intestinal bacteria can escape and cause systemic disease . It is postulated that the motile phagocyte ingests intestinal bacteria, transports them to extraintestinal sites, fails to accomplish intracellular killing, and then liberates the bacteria in the extraintestinal site . This hypothesis is consistent with many observations found in the literature: (1) The intestinal bacteria that most readily translocate out of the intestinal tract are classified as facultative intracellular pathogens . (2) Intestinal particles with no intrinsic motility (e.g., yeast, ferritin, starch) can translocate out of the intestinal lumen within hours after their ingestion . (3) The rate of translocation of intestinal bacteria can be altered with agents that modulate immune (including phagocytic) function . In the context of the mechanisms involved in intestinal immune responses, bacterial translocation appears to be a part of the normal antigen-sampling process of gut-associated lymphoid tissue . Systemic disease caused by translocating intestinal bacteria could be due to a maladaptation of the antigen-sampling process that has been designed to regulate the immune response to intestinal antigens. Proc Natl Acad Sci U S A, 1988 Sep, 85(18), 7036 - 40 Genetic exchange among natural isolates of bacteria: recombination within the phoA gene of Escherichia coli; DuBose RF et al.; An 1871-nucleotide region including the phoA gene (the structural gene encoding alkaline phosphatase, EC 3.1.3.1) was cloned and sequenced from eight naturally occurring strains of Escherichia coli . Alignment with the sequence from E . coli K-12 made apparent that there were 87 polymorphic nucleotide sites, of which 42 were informative for phylogenetic analysis . Maximum parsimony analysis revealed six equally parsimonious trees with a consistency index of 0.80 . Of the 42 informative sites, 22 were inconsistent with each of the maximum parsimony trees . The spatial distribution of the inconsistent sites was highly nonrandom in a manner implying that intragenic recombination has played a major role in determining the evolutionary history of the nine alleles . The implication is that different segments of the phoA gene have different phylogenetic histories. J Theor Biol, 1988 Aug 22, 133(4), 499 - 512 Comparison of the relative concentration of motile and non-motile bacteria in small pores; Skowlund CT et al.; The effect of small pores (similar in size to the stomata of plants) on the diffusion constants and relative concentrations of non-motile, randomly motile and chemotactic bacteria is considered . It is shown that although the Brownian diffusion constant of non-motile bacteria is a couple of orders of magnitude lower than the diffusion constant of motile bacteria, non-motile bacteria will still be present in both short (100 microns) and long (0.5 cm) pores in similar numbers to motile bacteria . It is postulated that this is due, at least in part, to the smaller amount of excluded volume for non-flagellated bacteria. Mol Gen Genet, 1988 Aug, 213(2-3), 409 - 20 Comparative analysis of genes encoding methyl coenzyme M reductase in methanogenic bacteria; Klein A et al.; The sequence of the gene cluster encoding the methyl coenzyme M reductase (MCR) in Methanococcus voltae was determined . It contains five open reading frames (ORF), three of which encode the known enzyme subunits . Putative ribosome binding sites were found in front of all ORFs . They differ in their degrees of complementarity to the 3' end of the 16 S rRNA, which is discussed in terms of different translation efficiencies of the respective genes . The codon usage bias is different in the subunit encoding genes compared with the two other ORFs in the cluster and two other known genes of Mc . voltae . This is interpreted in terms of increased translational accuracy of the highly expressed MCR subunit genes . The derived polypeptide sequences encoded by the five ORFs of the MCR cluster were compared to those of the respective genes in Methanobacterium thermoautotrophicum Marburg and Methanosarcina barkeri . Conserved regions were detected in the enzyme subunits, which are candidates for factor binding domains . Conserved hydrophobic sequences found in the alpha and beta subunits are discussed with respect to the membrane association of the enzyme. Infect Immun, 1988 Aug, 56(8), 2047 - 53 Immunochemical characterization of and isolation of the gene for a Borrelia burgdorferi immunodominant 60-kilodalton antigen common to a wide range of bacteria; Hansen K et al.; By crossed immunoelectrophoresis and Western blotting (immunoblotting), it was shown that Borrelia burgdorferi expresses the 60-kilodalton Common Antigen (CA) that is cross-reactive with an equivalent antigen in a wide range of remotely related bacteria . B . burgdorferi CA is strongly immunogenic . A B . burgdorferi genomic library was constructed by using a plasmid cloning system . Escherichia coli recombinants were screened for expression of immunodominant B . burgdorferi antigens . One of the recombinant clones expressed the 60-kilodalton CA of B . burgdorferi . The DNA region encoding B . burgdorferi CA was localized on a 2.3-kilobase fragment of the plasmid pKH1 . CA may have pathogenetic implications in Lyme borreliosis, since the CA of mycobacteria recently has been shown to play a role in the etiology of experimental autoimmune arthritis . The extensive cross-reactivity of this antigen may account for the low diagnostic specificity of the currently used serological tests in Lyme borreliosis. Surgery, 1988 Jul, 104(1), 49 - 56 Tissue inflammation without bacteria produces increased oxygen consumption and distant organ lipid peroxidation; Lalonde C et al.; An inflammatory focus was produced by implantation of gauze below the hide in the flanks of six sheep with flank lymph fistulas . Physiologic and metabolic parameters were monitored in the unanesthetized animals for 7 days, after which the gauze was removed and monitoring continued for another 5 days . Animals were then killed . Lung and liver tissue was inspected and analyzed for lipid peroxide content . Data were compared with those of six controls in which gauze was not implanted . We noted a transient significant increase (on day 1 only) in wound lymph, thromboxane B2, and 6-keto-PGF1 alpha from baseline values of 190 +/- 70 and 20 +/- 10 pg/ml to 1000 +/- 240 and 420 +/- 70 pg/ml, respectively . Plasma values were also significantly increased on day 1 . Body temperature increased by 1 degree C and cardiac index increased by 30% during this period, whereas oxygen consumption, VO2, was not significantly increased . The VO2 and cardiac index increased by 50% over baseline, beginning on day 5, whereas systemic vascular resistance decreased . Body temperature was not increased . These changes corresponded with an increase in wound lymph monocyte count from 0% to 15% of total . The VO2 and cardiac index remained increased after gauze removal . No bacteria were found in the wound . Postmortem analysis revealed a marked monocyte-macrophage infiltration in both lung and liver . Lung water, represented as water content over dry weight, was normal . Lung and liver lipid peroxidation, measured by the by-product malondialdehyde content, increased 300% and 90% over control values, respectively . We conclude that a local, nonbacteria-induced wound inflammation increases VO2, with the increase not corresponding to increase in body temperature . Distant organ changes, namely, changes in lung and liver, were also evident 5 days after gauze removal. J Clin Periodontol, 1988 Jul, 15(6), 360 - 4 Peripheral PMN cells in juvenile periodontitis . Increased release of elastase and of oxygen radicals after stimulation with opsonized bacteria; Asman B; In 12 patients with juvenile periodontitis (JP), stimulation of peripheral polymorphonuclear neutrophils (PMN) by opsonized bacteria showed increased release of free oxygen radicals and of elastase activity in relation to that of pair-matched healthy controls . The elastase increase was not associated with higher intracellular content of elastase, since the measurement of homogenized PMN cells did not differ between the patient group and the control group; nor did the spontaneous elastase activity of nonstimulated cells differ . Release of elastase by contaminating lymphocytes and platelets could be excluded, since no elastase activity from these cells or interference by these cells could be demonstrated in the assay system used . When formyl-methionyl-leucyl-phenylalanine was used as a stimulant, the chemiluminescence in the patient PMN cells did not differ with statistical significance from their pair-matched controls . The increased release of free oxygen radicals and of elastase seems to be a characteristic of the PMN cells in juvenile periodontitis, indicating hyperactive cells with possible pathogenic effects. Radiobiologiia, 1988 Jul-Aug, 28(4), 524 - 7 {Modification of the radiosensitivity of bacteria by glutaraldehyde}; Vasil'eva EI; A study was made of the combined effect of ionizing radiation and various concentrations of glutaric aldehyde (0.00125, 0.0025, 0.5, and 1 per cent) on viability of bacteria differing in a cell wall structure, radiosensitivity, and activity of DNA repair system . The combined effect of the two factors was shown to produce an effect of superadditive enhancement of bacterial cell death . The synergism was more pronounced in highly radiosensitive bacteria. Zh Mikrobiol Epidemiol Immunobiol, 1988 Jul, (7), 35 - 9 {Experimental study of the interaction of phages and bacteria in the environment}; Drozdova OM et al.; For the first time the possibility of the interaction of phages and bacterial cells in the environment, consisting in the adsorption and subsequent replication of viral particles, has been shown . The data obtained in this investigation provide grounds for using phages in the environment . Experiments with Escherichia coli M-17 and phage FM17, carried out on experimental models, have demonstrated that the use of phages in the environment completely prevents the realization of the transfer of enteral infections through everyday contacts and the contamination of children and adults under hospital conditions. J Bacteriol, 1988 Jun, 170(6), 2646 - 53 Polyacrylamide gel electrophoresis of the capsular polysaccharides of Escherichia coli K1 and other bacteria; Pelkonen S et al.; Methods were developed for the polyacrylamide gel electrophoretic analysis of capsular polysaccharides of bacteria with Escherichia coli K1 as a model . Conditions were determined for the rapid and gentle extraction of the K1 polysaccharide by incubation of the bacteria in a volatile buffer and for the subsequent removal of the putative phospholipid moiety attached to the reducing end of the polysaccharide . Detection of the polysaccharides after gel electrophoresis was carried out by fluorography of samples labeled by sodium borotritiide reduction or by combined alcian blue and silver staining . The smallest components could be detected only by fluorography, owing to diffusion during staining . Components of the E . coli K1 polysialic acid capsule ranging from monomers to 80 sialic-acid-unit-containing polymers could be separated as distinct bands in a ladderlike pattern . A maximum chain length of 160 to 230 sialyl residues was estimated for the bulk of the K1 polysaccharide from the nearly linear reciprocal relationship between the logarithm of the molecular size and the distance of migration . Gel electrophoresis of capsular polysaccharides of other bacterial species revealed different electrophoretic mobilities for each polysaccharide, with a ladderlike pattern displayed by the fastest-moving components . There are many potential applications of this facile method for the determination of the sizes of molecules present in a polydisperse polysaccharide sample . When combined with the simple method for the isolation of the capsule, as in the case of the K1 capsule, it provides an efficient tool for the characterization and comparison of the capsular polysaccharides of bacteria. Acta Odontol Scand, 1988 Jun, 46(3), 177 - 80 Influence of pH on the suspension stability of some oral bacteria; Simonsson T et al.; The purpose of the present study was to investigate the suspension stability of some oral bacteria at some clinically relevant pH levels . Through determinations of the electrophoretic mobility and sedimentation behavior at pH 5, 6, and 7, it was shown that within this pH range estimations of both the zeta-potentials and colloidal stability were pH-dependent for the bacteria and bacterial suspensions tested . The observations are in line with the DLVO theory for lyophobic sols and indicate that bacteria behave like colloidal particles when suspended in certain media . The colloidal behavior further seemed to vary in relation to bacterial species and strains. J Dent Res, 1988 May, 67(5), 846 - 50 Induction of activated lymphocyte killing by bacteria associated with periodontal disease; Lindemann RA et al.; Complex interactions occur among host defense cells during bacterial infection . Bacteria and bacterial products may enhance or inhibit the effector and regulatory activity of human lymphocytes . Accordingly, we tested the ability of human periodontal pathogens to activate peripheral blood lymphocytes using standard chromium-release assays to measure lymphocyte-mediated cytolysis . Human adherent-cell depleted peripheral blood lymphocytes (PBL) with the addition of glutaraldehyde-fixed bacteria at a 5:1 bacteria:lymphocyte ratio were incubated at 37 degrees C for 24 hr in RPMI 1640 medium . Six of eight bacteria tested significantly augmented lymphocyte killing of the natural killer (NK) cell-sensitive human erythroleukemia cell line K562 . E . corrodens, representing activating bacteria, was also able to induce the killing of NK-resistant targets (M14, Raji), comparable with induction by interleukin-2 . Lipopolysaccharides extracted from A . actinomycetemcomitans strains, when incubated with PBL, were able to enhance cytotoxicity without the presence of whole bacteria . A majority of cytotoxicity was mediated by NK cells bearing Leu-11 and NKH-1 markers. Ann Surg, 1988 Apr, 207(4), 387 - 98 Effect of T cell modulation on the translocation of bacteria from the gut and mesenteric lymph node; Maddaus MA et al.; Although the ability of the gut-associated lymphoid tissue (GALT) to respond to orally ingested foreign antigens has been studied extensively, its function in preventing or limiting escape of resident gut bacteria has not been assessed . The following studies were performed to examine what role cell-mediated immunity (CMI) plays in this process . The ability of suppression of CMI to induce escape of gut bacteria (translocation) to the mesenteric lymph node (MLN) in immunocompetent mice whose gut flora was unaltered was examined . Administration of cyclosporine or anti-L3T4 antibody failed to induce translocation of indigenous gut bacteria after 7 or 14 days of treatment . Antithymocyte globulin (ATG) also failed to induce translocation after 7 days of treatment, despite depletion of all Thy 1, Lyt 1, L3T4, and Lyt 2 positive cells from the spleen, MLN, and intestine as demonstrated by immunofluorescent microscopy . Finally, cultures of the MLN, spleen, liver, and peritoneum of T cell-deficient BALB/c nude mice and their heterozygous T cell-replete littermates were also sterile, demonstrating that congenital suppression of T CMI also does not lead to translocation of indigenous gut bacteria . The role of CMI in limiting systemic spread of bacteria that were already translocating to the MLN was also examined . Translocation of Escherichia coli C25 to the MLN was induced by gastrointestinal (GI) monoassociation, which leads to translocation of E . coli C25 to the MLN in 80-100% of mice . Treatment with ATG during monoassociation failed to induce spread of E . coli C25 to the spleen, liver, or peritoneum, despite the same degree of T cell depletion achieved with ATG in the previous experiment . Monoassociation of conventional T cell-deficient BALB/c nude and heterozygous mice and germ-free T cell-deficient BALB/c nude and heterozygous mice also did not lead to spread of E . coli C25 beyond the MLN . However, in ATG-treated, conventional nude, and germ-free nude mice, the average number of translocating E . coli C25 per MLN was consistently higher . In separate experiments the ability of stimulation of T cell function to inhibit translocation of E . coli C25 was examined . Recombinant interleukin-2, 25,000 units, was administered intraperitoneally every 8 hours during exposure to E . coli C25 . This reduced the incidence of translocation of E . coli C25 from 85% to 51% (p = 0.02) . Suppression of CMI, either systemically or within the GALT, has a minimal influence on the mechanisms by which the normal gut flora are translocated to the MLN.(ABSTRACT TRUNCATED AT 400 WORDS) Acta Odontol Scand, 1988 Apr, 46(2), 83 - 7 Effects of cations on the colloidal stability of some oral bacteria; Simonsson T et al.; The colloidal stability of seven strains of oral bacteria was studied at various concentrations of mono-, di-, and multi-valent metal counterions in the suspending media . Alterations in the concentration and the valency of the counterions were shown to influence the colloidal stability of the bacterial suspensions, as determined by their rate and time of initial sedimentation . The observations were in general in agreement with the accepted theories for colloidal stability . The results support previously made suggestions that under certain experimental conditions oral bacteria behave like colloidal particles. Can J Microbiol, 1988 Apr, 34(4), 390 - 4 Speculations on the growth strategy of prosthecate bacteria; Koch AL; Appendaged bacteria with stalks that are extensions of the cell wall have had to solve the problems of growing the stalk as a tube of constant diameter and of partitioning their chromosomes into the asymmetric daughter cells . Although no experimental proof is given, it is suggested that both processes depend on the attachment of the chromosome origin and terminus to the wall at special terminal sites that contain the basal body (motor assembly) for flagellar motion. Ann Inst Pasteur Microbiol, 1988 Mar-Apr, 139(2), 261 - 72 {Enumeration and size of planktonic bacteria determined by image analysis coupled with epifluorescence}; Van Wambeke F; The interest of the image analysis procedure is the time-saving in automated planktonic bacterial counting and sizing, with the possibility of manual visual field control at all times . Bacterial biomass (in number and volume) and bacterial projected area histograms were determined with a microcomputer . Performance limits of image-analysed epifluorescence microscopy were: camera sensitivity, considering the very low fluorescence levels on stained bacteria; pixel-micron conversion factor, and the impossibility of the apparatus distinguishing between bacteria and fluorescent small particles . This method is not of interest for counting sediment bacteria. Biofizika, 1988 Mar-Apr, 33(2), 328 - 32 {Kinetic analysis of the chemotaxis of bacteria}; Zaval'skii LIu; On the basis of a kinetic model of bacterial chemotactic movement the system of differential equations was reduced to describe the phenomenon of bacterial bonds migration . It follows that Keller-Segel equation is a private case of a more general "diffusion approximation" of the kinetic model . The functional parameters of the reduced equation for E . coli K-12 are estimated. Biofizika, 1988 Mar-Apr, 33(2), 323 - 7 {Effect of heavy water on the viability of bacteria}; Dronova NV et al.; Influence of heavy water (D2O) on the membrane energization, the efflux of hydrogen ions and the respiration of bacteria E . coli M-17 was studied . As has been shown, heavy water of a low concentration (0.05-0.20% v/v) activates and of a high concentration (above 10%) inhibits the absorption of lipophilic cation tetraphenylphosphonium (TPP+) and of oxygen by cells . The return of these characteristics to the initial levels after the removal of D2O points to a reversible action of D2O . A protective effect of D2O towards membrane energization and rate of respiration on dried cells was observed . This fact is in agreement with the data on viability of bacteria . The indicated protective action increases at the stage of rehydration in the presence of D2O. Int J Biomed Comput, 1988 Mar, 22(2), 107 - 19 Microcomputer application of Bayesean probability testing for the identification of bacteria; Jilly BJ; A computer program (BACTID) is described which facilitates the identification of bacteria based on a priori data and Bayesean probability testing . The program is not limited to a specific format, has a short execution time, can be easily applied to a variety of situations, and can be run on almost any microcomputer system operating under either 8-bit CP/M or 16-bit MS-DOS/PC-DOS . Additionally, BACTID (1) is not limited to one type of computer (hardware independent), (2) is not limited by size of the computer's random access (RAM independent), (3) can recognize various data bases matrices (format independent), (4) is able to compensate for missing data and (5) allows for various methods of data entry . The efficacy of the program was checked against a commercially available test system and a 99.34% agreement was obtained . Also, the execution time for a 46 x 21 element data matrix was as little as 3.5 s . These results show that microcomputer identification programs are not only viable alternatives to code book registers, but also offer flexibility which is not found in commercial systems. Mutagenesis, 1988 Mar, 3(2), 165 - 8 Adaptive response to simple alkylating agents in the phototrophic bacteria Rhodobacter capsulatus and R.sphaeroides; Vericat JA et al.; The presence of an adaptive response to low doses of alkylating chemicals in the phototrophic bacteria Rhodobacter sphaeroides and R.capsulatus has been studied . Results obtained show that both strains display this repair response against the challenge doses of N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), when they are pretreated with low doses of this compound for 120 min . The adaptive response of both R.sphaeroides and R.capsulatus induced an increase of cell survival and a decrease of mutagenesis in the MNNG-pretreated cells . Furthermore, the MNNG-induced adaptive repair also gives protection to diethylsulphate and ethylmethanesulphonate in both phototrophic bacteria . Finally, the MNNG-promoted adaptive response is sensitive to inhibitors of protein synthesis such as chloramphenicol, indicating that this DNA repair mechanism needs protein synthesis in R.sphaeroides and R.capsulatus, in a way similar to that which occurs in Escherichia coli. Radiobiologiia, 1988 Mar-Apr, 28(2), 262 - 4 {Effect of laser radiation and combined ionizing and laser radiation on the cell-division time of bacteria}; Simonian NV et al.; Irradiation of E . coli K-12 cells of the wild-type AB 1157 strain with helium-neon continuous laser radiation leads to a temporary delay in their division . The delay was found to be the same in cells exposed to ionizing radiation alone and in cells exposed to a combination of ionizing and laser radiation. Proc Natl Acad Sci U S A, 1988 Mar, 85(5), 1586 - 9 Targeted mutations induced by a single acetylaminofluorene DNA adduct in mammalian cells and bacteria; Moriya M et al.; Mutagenic specificity of 2-acetylaminofluorene (AAF) has been established in mammalian cells and several strains of bacteria by using a shuttle plasmid vector containing a single N-(deoxyguanosin-8-yl)acetylaminofluorene (C8-dG-AAF) adduct . The nucleotide sequence of the gene conferring tetracycline resistance was modified by conservative codon replacement so as to accommodate the sequence d(CCTTCGCTAC) flanked by two restriction sites, Bsm I and Xho I . The corresponding synthetic oligodeoxynucleotide underwent reaction with 2-(N-acetoxy-N-acetylamino)-fluorene (AAAF), forming a single dG-AAF adduct . This modified oligodeoxynucleotide was hybridized to its complementary strand and ligated between the Bsm I and Xho I sites of the vector . Plasmids containing the C8-dG-AAF adduct were used to transfect simian virus 40-transformed simian kidney (COS-1) cells and to transform several AB strains of Escherichia coli . Colonies containing mutant plasmids were detected by hybridization to 32P-labeled oligodeoxynucleotides . Presence of the single DNA adduct increased the mutation frequency by 8-fold in both COS cells and E . coli . Over 80% of mutations detected in both systems were targeted and represented G.C----C.G or G.C----T.A transversions or single nucleotide deletions . We conclude that modification of a deoxyguanosine residue with AAF preferentially induces mutations targeted at this site when a plasmid containing a single C8-dG-AAF adduct is introduced into mammalian cells or bacteria. J Reprod Immunol, 1988 Mar, 12(4), 315 - 9 Deposition of C3 on bacteria in the mouse uterus after mating; Parr EL et al.; A previous study demonstrated that several species of bacteria were present in the mouse uterine lumen on the day after mating, and that many of these bacteria had immunoglobulins bound to their surface . Neutrophilic leukocytes containing phagocytosed bacteria were also present in the lumen . Since bacteria are phagocytosed efficiently only when they are opsonized by the binding of specific antibody or C3b or both to their surface, we investigated whether the uterine bacteria were coated with C3 . Immunolabeling demonstrated that an antigenic portion of C3, possibly C3b, was bound to many of the uterine bacteria . This observation suggests that bacteria in the mouse uterus after mating may be opsonized by both antibody and complement and that phagocytosis of these bacteria by neutrophils may play an important role in returning the uterus to an aseptic state before implantation. Vet Med (Praha), 1988 Mar, 33(3), 129 - 33 {The occurrence and properties of Selenomonas ruminantium bacteria in calves during the time of milk feedings}; Kmet V et al.; The occurrence, morphological properties, urease and alpha-amylase activities of Selenomonas ruminantium were investigated in calves in the period of milk nutrition . The average number of the organisms was found to range between 10(7) and 10(8) per 1 millilitre of rumen contents . The alpha-amylase activity of the Selenomonas strains ranged from 0.1 to 8.8 ncat.ml-1 whereas their urease activity ranged from 6.3 to 261 ncat.ml-1 of nutrient medium . The presence of morphologically typical Selenomonas ruminantium and spontaneous formation of spheroplasts were found by electron microscopic examination. Microbiol Sci, 1988 Mar, 5(3), 78 - 81 Formation of two forms of nitrogenase and effects of its switch-off by ammonia in purple bacteria; Yakunin AF et al.; The switch-off of nitrogenase by ammonia in cells of the purple bacteria is not due to the conversion of nitrogenase into an inactive form . The latter is probably an initial stage of the enzyme degradation in the presence of excess nitrogen. Appl Environ Microbiol, 1988 Feb, 54(2), 600 - 3 Methanogenic bacteria from human dental plaque; Belay N et al.; Samples of human dental plaque were examined for the presence of methanogenic bacteria . Of 54 samples from 36 patients, 20 yielded H2/CO2-using methanogenic enrichment cultures . All methanogen-positive samples were from patients with some degree of periodontal disease . The predominant populations in the enrichments had morphologies characteristic of Methanobrevibacter spp . In six enrichments derived from three patients, the common methanogen was antigenically similar to Methanobrevibacter smithii . The same was true for the three methanogenic isolates obtained in axenic culture from a fourth patient . The six enrichments and two of the three isolates were antigenically closer to strain ALI than to PS . Two of the enrichments also had subpopulations with weak antigenic similarity to Methanosphaera stadtmanae . The data indicate that methanogens in the oral cavity of humans are antigenically close to those found in the intestinal tract. Appl Environ Microbiol, 1988 Feb, 54(2), 555 - 60 Temporal and geographical distributions of epilithic sodium dodecyl sulfate-degrading bacteria in a polluted South Wales river; Anderson DJ et al.; Epilithic bacteria were isolated nonselectively from riverbed stones and examined by gel zymography for their ability to produce alkylsulfatase (AS) enzymes and thus to metabolize alkyl sulfate surfactants such as sodium dodecyl sulfate . The percentages of AS+ isolates from stone epilithon at five sites from the source to the river mouth were measured on five sampling days spread over 1 year . The results showed that (i) the prevalence of epilithic AS+ strains (as a percentage of all isolates) was much higher at polluted sites than at the source; (ii) when averaged over the whole river, percentages of AS+ strains were significantly higher at the end of summer compared with either the preceding or the following winter; (iii) analysis of site-sampling time interactions indicated that water quality factors (e.g., biochemical oxygen demand and dissolved oxygen concentration) rather than climatic factors determined the distributions of epilithic AS+ isolates; (iv) constitutive strains were the most prevalent (7.2% of all isolates), with smaller numbers of isolates with inducible (4.5%) and repressible (1.7%) enzymes. Appl Environ Microbiol, 1988 Feb, 54(2), 502 - 6 Postprandial changes in methanogenic and acidogenic bacteria in the rumens of steers fed high- or low-forage diets once daily; Leedle JA et al.; Four ruminally fistulated Hereford steers (400 kg) were fed two isocaloric diets at 1.5 x maintenance once daily in a repeated measurement crossover experiment . Postprandial changes in hydrogen-oxidizing, carbon dioxide-reducing bacterial groups were monitored . The methanogenic bacterial populations were present at densities of 4 x 10(8) to 8 x 10(8)/g of ruminal contents on either the high- or low-forage diet . Numbers remained constant postprandially on the high-forage diet but showed a distinct rise and fall with the once-daily feeding of the low-forage diet . Presumed hydrogen- and carbon dioxide-utilizing, acid-producing (acidogenic) bacteria were present between 2 x 10(8) and 12 x 10(8)/g of ruminal contents, with the density of the low-forage population being twofold higher than that of the high-forage population . Acidogenic bacteria exhibited similar postprandial changes on both diets, with the predominant shift being associated with the feeding event . This is the first study which documents the postfeeding trends in ruminal methanogenic bacteria on specified, production-level diets . It is also the first study to suggest that other hydrogen-oxidizing, carbon dioxide-reducing bacteria which produce acid instead of methane are present at high population densities in the normally fed adult ruminant. Zh Mikrobiol Epidemiol Immunobiol, 1988 Feb, (2), 51 - 4 {Use of the coagglutination reaction of yeast-like Candida maltosa fungi for detecting fimbriae in intestinal bacteria}; Kulinich LI et al.; The capacity of nonpathogenic yeast-like C . maltosa strains to coagglutinate Escherichia coli has been studied . C . maltosa cells have also been shown to coagglutinate E . coli possessing mannose-sensitive adhesins in a wide range of their concentrations (5-140 bacterial cells per C . maltosa cell) . Strains belonging to types CFA/I and CFA/II with fimbriae, similarly to their corresponding paired genetically related strains without these adhesins, are practically incapable of agglutinating C . maltosa cells, while strains K88 and B41 react with them . The reaction occurs at a concentration of 9.5-37.0 and 38.0-55.5 bacteria respectively per C . maltosa cell and is not inhibited by 1% d-mannose . The suggestion that C . maltosa cell surface glycoproteins contain not only receptors for E . coli fimbriae, type I, but also components similar in their structure to receptors specific to the mannose-resistant adhesins of strains K88, K99 and 41, has been confirmed by hemagglutination inhibition with C . maltosa surface antigens as inhibiting agents. J Steroid Biochem, 1988 Feb, 29(2), 185 - 9 The biological assessment of vitamin D3 metabolites produced by rumen bacteria; Gardner RM et al.; Biological assays were performed to evaluate 10-oxo-19-nor-vitamin D3 (10-oxo-D3) and 5(E) 25-hydroxy-10-oxo-19-nor-vitamin D3 (25-OH-10-oxo-D3) two bacterial products of vitamin D3 (D3) and 25-hydroxyvitamin D3 (25-OHD3) metabolism, respectively . The 5(Z) and 5(E) isomers of 10-oxo-D3 were, respectively, 40- and 80-fold less active than D3 in stimulating Ca+2 absorption from the gut . 25-Hydroxy-10-oxo-D3 did not stimulate Ca+2 absorption . Only 5(Z) 10-oxo-D3 induced mobilization of bone Ca+2 . In addition, both 10-oxo-D3 and 25-OH-10-oxo-D3 showed poor affinities for either the plasma D3-binding protein or the thymus 1,25-dihydroxyvitamin D3 {1,25-(OH)2D3} receptor . 10-Keto-D3 exhibited a plasma half-life of only 6 min . This was a much shorter half-life than that exhibited by other vitamin D metabolites and was expected because of the poor affinity 10-oxo-D3 has for the plasma vitamin D binding protein . Bacterial metabolism of D3 deactivates the vitamin, which allows ruminants to tolerate relatively large oral doses of D3. Biochim Biophys Acta, 1988 Jan 25, 949(1), 65 - 70 Protein synthesis in polyamine-deficient bacteria during amino-acid starvation; Nastri HG et al.; Amino-acid starvation in polyamine-auxotrophic bacteria grown in the presence of putrescine provokes a marked inhibition of protein synthesis . This inhibition is almost completely relieved in polyamine-depleted cells . The differential behaviour of bacterial protein synthesis depending on the endogenous levels of polyamines is not due to a change in the uptake of amino acids used to measure protein synthesis, nor to the decreased growth rate of polyamine-depleted cells . During leucine starvation, cells grown with putrescine synthesized a somewhat lower amount of high-molecular-weight proteins than polyamine-depleted bacteria . In addition, cells with normal endogenous levels of polyamines accumulated significant amounts of 62 and 41 kDa polypeptides as well as several low-molecular-weight peptides. Antonie Van Leeuwenhoek, 1988, 54(3), 207 - 20 Interconversion of F430 derivatives of methanogenic bacteria; Keltjens JT et al.; F430 is the prosthetic group of the methylcoenzyme M reductase of methanogenic bacteria . The compound isolated from Methanosarcina barkeri appears to be identical to the one obtained from the only distinctly related Methanobacterium thermoautotrophicum . F430 is thermolabile and in the presence of acetonitrile or C10-4 two epimerization products are obtained upon heating; in the absence of these compounds F430 is oxidized to 12,13-didehydro-F430 . The latter is stereoselectively reduced under H2 atmosphere to F430 by cell-free extracts of M . barkeri or M . thermoautotrophicum . H2 may be replaced by the reduced methanogenic electron carrier coenzyme F420. Pharmacology, 1988, 36 Suppl 1, 172 - 9 Metabolism of sennosides by human intestinal bacteria; Hattori M et al.; During the course of studies on the metabolism of sennosides by human intestinal bacteria, an enzyme which takes part in the reduction of sennosides and sennidins was originally isolated from Peptostreptococcus intermedius . This enzyme catalyzed the electron transfer from NADH to FAD, FMN or benzyl viologen, which reduced nonenzymatically sennosides and sennidins to 8-glucosyl-rhein anthrone and rhein anthrone, respectively. Radiobiologiia, 1988 Jan-Feb, 28(1), 117 - 20 {Sorption of bacteria by blood cells as an indicator of the reaction of animals to the action of different doses of gamma rays}; Darenskaia NG et al.; In experiments with mice, guinea pigs, and dogs, a study was made of the sorptive capacity of peripheral blood cells after different gamma-radiation doses with reference to living Escherichia coli cells . The sorptive capacity of blood cells was inhibited in exposed animals the inhibition being maximum during the first 3 days following irradiation . Homologous immunoglobulin administered to mice 24 h before irradiation prevented the diminution of the sorptive capacity of cells and stimulated it during the first week following irradiation. Mol Biol (Mosk), 1988 Jan-Feb, 22(1), 145 - 50 {Genetic engineering of peptide hormones . III . Cloning of the swine growth hormone cDNA and construction of the gene for expression of the hormone in bacteria}; Zhvirblis GS et al.; The clones containing cDNA of porcine growth hormone were obtained using poly(A)-RNA from porcine pituitary as a template for reverse transcriptase . The analysis of their nucleotide sequences revealed that these cDNAs have differences not only on the nucleotide level but also on the amino acid level, i . e . the polymorphism of mRNA and protein occurs in the case of porcine growth hormone . To create the construction for expression of porcine growth hormone in E . coli, the 5'-part of cDNA, coding the first 15 amino acids of the mature hormone, was substituted by the artificial sequence. Arch Tierernahr, 1988 Jan, 38(1), 1 - 11 {The effect of different centrifugation conditions for the isolation of mixed rumen bacteria, on their nitrogen and diaminopimelic acid content}; Krawielitzki R et al.; Three cows were given two rations, a silage diet (3 animals) and a green forage diet (2 animals) . Samples of rumen content were collected and aliquots of these were separated in a fraction of feed particles and protozoa (FP-fraction) and a fraction of mixed bacteria, varying the conditions of differential centrifugation . The low speed centrifugation was practised at 100 X g/5 min, 400 X g/10 min, 1000 X g/10 min, and 2000 X g/10 min . High speed conditions were 30,000 X g/30 min 4 degrees C . The lyophylisated sediments were used for determination of N and DAP . The content of N gave similar results for all fractions of mixed bacteria, the mean value being 7.43 +/- 0.48% (n = 20), while the N-content of the FP-fractions being 5.68 +/- 0.37% (n = 19) . The N:DAP-ratio gave similar values for the cows fed the silage diet, the values were 29.45 +/- 1.56 (n = 12) . The values for the cows receiving the green forage diet differed, the mean values were 23.08 +/- 0.88 and 42.01 +/- 5.81 (n = 5), respectively . In all five experiments highest ratios were found at 100 X g . Further investigations showed that storage at -20 degrees C rumen fluid after isolation of feed particles and protozoa decreased both the N- and DAP- content without affecting the N:DAP-ratio . Centrifugation at low speed with 100 X g resulted in a markedly decreased contamination with DAP in all the FP-fractions . Optimal conditions for separation of feed particles and protozoa from rumen fluid to get a fraction best reflecting the rumen bacterial populations are 100 X g/5 min. Mol Microbiol, 1988 Jan, 2(1), 9 - 17 DNA sequence of the gene scrA encoding the sucrose transport protein EnzymeII(Scr) of the phosphotransferase system from enteric bacteria: homology of the EnzymeII(Scr) and EnzymeII(Bgl) proteins; Ebner R et al.; The nucleotide sequence of the structural gene, scrA, which codes for sucrose-specific EnzymeII(Scr) (EII(Scr)) of the phosphoenolpyruvate-dependent carbohydrate:phosphotransferase system (PTS), was determined . EllScr requires an EnzymeIII, the product of the gene crr, for full activity . The gene scrA is preceded immediately by a classical Shine-Dalgarno sequence (AAGAGGGTA) . It contains 1368 nucleotides with an increased GC-content (58%) corresponding to a polypeptide of 455 amino acid residues (Mr 47,500) . The protein has the hydropathic profile (average hydropathy +0.82) of an integral membrane protein lacking extended alpha-helical structures and a signal peptide . Comparison with the sequence of the beta-glucoside-specific EnzymeII (EII(Bgl), 625 amino acids, Mr 66,480; Bramley and Kornberg, 1987a; Schnetz et al., 1987) revealed strong homologies between EiI(Scr) and the first 458 residues of EII(Bgl) . The 162 carboxyterminal residues of EII(Bgl), however, showed a high homology with the sequence of EnzymeIII (Nelson et al., 1984), a homology also described recently by Bramley and Kornberg (1987b) . The evolutionary and functional significance of the similarities with four other EnzymesII is discussed. Gastrointest Endosc, 1988 Jan-Feb, 34(1), 19 - 22 The role of bacteria in the blockage of biliary stents; Leung JW et al.; Recurrent jaundice and cholangitis due to stent occlusion by biliary sludge is a major complication of endoscopic stenting for malignant obstructive jaundice . Scanning electron microscopy study of the blocked stents revealed the sludge to consist of a mixture of bacteria and amorphous material . In vitro study using scanning electron microscopy demonstrated the attachment of bacteria to a segment of stent perfused with infected bile containing live bacteria . Associated with the microcolonies of bacteria was a collection of amorphous material forming a dense concretion on the surface of the stent . This phenomenon was not observed in experiments using sterile bile or with infected bile sterilized by formalin treatment or autoclaving . It was concluded that live bacteria are necessary for the initiation of biliary sludge formation which leads to subsequent stent blockage. Scand J Gastroenterol, 1988 Jan, 23(1), 121 - 8 Production of peptides inducing chemotaxis and lysosomal enzyme release in human neutrophils by intestinal bacteria in vitro and in vivo; Chadwick VS et al.; Low molecular weight (Mr 200-1500) N-formylated peptides that stimulate many leucocyte functions, including chemotaxis and lysosomal enzyme release, have previously been isolated from Escherichia coli cultures . We have used high-performance liquid chromatography and bioassay techniques to study production of such peptides by intestinal bacteria in vitro and their activity in intestinal luminal contents, obtained by in vivo dialysis methods . Bioactivity was detected in culture supernatants of all 11 species of bacteria so far investigated, was resistant to digestion with aminopeptidase, but was destroyed by carboxypeptidase, confirming that bioactive moieties were amino-terminal-blocked peptides . By similar isolation procedures, pronase-sensitive bioactive factors have been demonstrated in human rectal dialysates from normal subjects and patients with Crohn's disease . In the patients, bioactivity in dialysates was not observed after treatment with broad-spectrum poorly absorbed antibiotics . The gut may be a reservoir or source of bacterial peptides that could promote an inflammatory response should they cross the 'mucosal barrier'. Nauchnye Doki Vyss Shkoly Biol Nauki, 1988, (5), 83 - 8 {Mutants of the phototrophic bacteria Rhodobacter sphaeroides sensitive to the mutagenic action of long-wave ultraviolet light}; Rodina NE et al.; The mutagenic action of near ultraviolet (NUV, greater than or equal to 280) nm) on purple phototrophic soil bacteria Rhodobacter sphaeroides: wild strain 2R and 12 mutants obtained earlier sensitive to UV derivates (UVS) was investigated . The mutagenic action of NUV was measured by induction of resistance to tetracycline (Tet) and nalidixic acid (Nal) and reversion of pigment mutants to wild-type phenotype . The NUV light induces the mutations of resistance to Nal and Tet in wild-type strain 2R; the UVS mutants differed greatly in their NUV-induced mutability . Three UVS mutants were characterized by greatly increased mutability in all analysed loci; slight mutability was found in seven mutants . On the basis of the data obtained it has been concluded that the UVS mutants R . sphaeroides can be used as test organisms in estimation of mutagenic activity of NUV . The molecular mechanisms and genetic control of NUV-induced mutagenesis are discussed. Arch Oral Biol, 1988, 33(8), 579 - 87 pH changes during simultaneous metabolism of urea and carbohydrate by human salivary bacteria in vitro; Sissons CH et al.; The effect of the wide natural variation in oral ureolysis rates on the pH changes resulting from simultaneous metabolism of 25 mM urea and 2.8 mM glucose in salivary-sediment bacteria were investigated . The pH curves were complex, and included distinctive plateaux indicative of balanced acid and base production . These neutralization plateaux occurred at different pHs, which were a function (r2 = 0.98) of the ureolytic rate as measured by the log of the initial pH-change rate in the urea-only reaction . In the simplest case, the pH curve was characterized by a rise or fall to the neutralization plateau, a variable period of time at the plateau (up to 1 h), then a pH rise . The pattern of pH changes induced by glucose alone varied between different sediments: in some cases, the pH decreased smoothly to an end-point; in others, the curve was more complex, and these features became superimposed on the urea/glucose curve . The rate of ureolytic ammonia release was almost constant and unaffected by simultaneous carbohydrate metabolism . Concomitant metabolism of endogenous carbohydrate present in sediments prepared 1-2 h following a meal was of sufficient magnitude to affect ureolytic pH curves . If the ureolytic activity was high, this effect was negligible; if it was low, metabolism of the endogenous carbohydrates could completely suppress the ureolytic pH rise . Soluble salivary components had little effect on ureolysis but pH changes were modified by buffering, and the presence of urea, ammonia, N-catabolic and acidogenic substrates in the saliva. Clin Ther, 1988, 10 Spec No, 52 - 5 The origin of bacteria isolated from patients after transurethral prostatectomy; Fujita K; Of 250 patients undergoing transurethral prostatectomy, 34 had significant bacteriuria after surgery . In 20 patients, including some without significant colonies of bacteria, the same organisms were found before surgery . Closed surgical systems and aseptic techniques can prevent infection from outside the patient, but bacteriuria can still develop from within the patient. Virchows Arch A Pathol Anat Histopathol, 1988, 414(1), 29 - 37 Acute human pyelonephritis: leukocytic infiltration of tubules and localization of bacteria; Ivanyi B et al.; The fine structural details of how leukocytes appear in the lumen of tubules and the localization of bacteria in the tubulo-interstitial space were studied by light and electronmicroscopy in renal cortical biopsy specimens from three patients with acute pyelonephritis . The cells of interstitial infiltrates infiltrated and sometimes disrupted the cortical collecting tubules preferentially, while inflammatory infiltration of the proximal and distal convoluted tubules occurred more rarely . Since the emigration of tubular wall-localized individual leukocytes into the lumen was not observed even in long series of thin sections, focal inflammatory disruption of the uriniferous ducts was considered to be the morphological basis of the intratubular accumulation of leukocytes . The structural simplicity of the collecting tubular cells is suggested to be the reason for their preferential involvement in the drainage of the interstitial suppuration, although a role for specific carbohydrate receptors cannot be excluded . The bacteria were usually found within the neutrophilic granulocytes and macrophages of the interstitial infiltrates, and within and among the cells of leukocyte casts . Additionally, pure bacterial colonies were noticed in the lumen of a few collecting tubules . The problem of the adherence of the bacteria to the surface of the tubular cells is discussed. Gene, 1988, 62(1), 153 - 8 Transfer of mlt mutations into polyomavirus intronless genomes by intramolecular recombination in bacteria; Pinsonneault C et al.; We describe a modification of the procedure of Weber and Weissmann {Nucl . Acids Res . 11 (1983) 5661-5669} for the formation of hybrid genes by in vivo recombination to introduce two separate mutations into the same gene . The mutants of interest are inserted as head-to-tail tandems in a bacterial plasmid in such a way that the 5'-proximal mutation is located upstream from the mutant with the more distal mutation . Propagation of the plasmid in a rec+ strain of Escherichia coli allows recombination between homologous sequences in the insert . DNA with the size expected for the recombinant plasmid is isolated by agarose gel electrophoresis, cloned in a recA strain, and characterized by restriction endonuclease mapping . Using this procedure, we have transferred the deletion from polyomavirus mutant dl-8 into other mutant genomes lacking the intervening sequences for either middle T or large T. Mutat Res, 1988 Jan, 197(1), 15 - 22 Mutagenic DNA repair in Escherichia coli . XV . Mutation frequency decline of ochre suppressor mutations in umuC and lexA bacteria occurring between ultraviolet irradiation and delayed photoreversal; Bridges BA et al.; Tryptophan-independent mutations were induced in CM1141 trpE65 umuC122::Tn5 following exposure to ultraviolet light (UV) plus delayed photoreversal . The mutations appeared to be exclusively class 2 ochre suppressors and showed mutation frequency decline (MFD) when the bacteria were incubated in glucose-salts medium after UV and before photoreversal . The phenomenon was similar to MFD after normal UV mutagenesis of umu+ bacteria, being inhibited in the presence of caffeine or in the absence of glucose . Mutations were also induced by UV plus delayed photoreversal in the lexA (Ind-) strain CM561, and the yield was higher than in the umuC strain suggesting that potentially mutagenic configurations might be removed or altered to some extent by the product of a gene under lexA control such that fewer were available for misincorporation events . MFD was also demonstrated in CM561 showing that this process is not dependent on the derepression of any genes under lexA control . MFD could still be demonstrated 23 min after UV at a time when most misincorporations seem to have occurred, but for technical reasons the possibility could not be excluded that the misincorporations in question could have occurred during rather than before the exposure to photoreversing light . Delayed photoreversal mutagenesis of normally non-UV-mutable strains has been interpreted as a first stage (misincorporation) of normal UV mutagenesis . The present results are consistent with this interpretation since MFD of suppressor mutations is a feature of both processes. Ann Inst Pasteur Microbiol, 1988 Jan-Feb, 139(1), 45 - 58 Expression of a poliovirus neutralization epitope at the surface of recombinant bacteria: first immunization results; Charbit A et al.; We devised a procedure to construct strains of Escherichia coli which expose at their surface a foreign antigen genetically inserted into LamB, an outer membrane protein . In particular, we showed that amino acid residues 93-103 of poliovirus type 1 capsid polypeptide VP1, which correspond to the C3 neutralization epitope, when inserted into two different external loops of LamB (after residues 153 and 374 of the mature protein), yielded the synthesis of stable hybrid proteins named, respectively, 153-C3 and 374-C3 . The poliovirus epitope was accessible to monoclonal antibody C3 at the cell surface . In the present work, these two hybrid proteins were injected into rabbits by the intravenous route in the form of live recombinant bacteria, and the humoral response to the poliovirus epitope was studied . With construction 153-C3, the subcutaneous route was also assayed using solubilized hybrid protein . The C3 viral sequence inserted in the two different regions of LamB were found to be immunogenic . Different types of antibodies specific to the C3 peptide were raised with the two construction: anti-peptide and antiviral particle antibodies . These first results indicate that the LamB presentation vector system constitutes a mode of peptide coupling which may lead to the elaboration of a new type of live vaccine. Leukemia, 1988 Jan, 2(1), 1 - 5 Expression in bacteria of beta-galactosidase fusion proteins carrying antigenic determinants of the two X gene products of bovine leukemia virus; Willems L et al.; A cDNA corresponding to the bovine leukemia virus post-envelope region (X gene) was subcloned into the lambda gt11 expression vector . Two large protein fragments corresponding respectively to the long and short open reading frames of the X region were expressed as beta-galactosidase fusion proteins . These products were specifically recognized by sera from bovine leukemia virus-infected cattle. Eur J Biochem, 1987 Dec 30, 170(1-2), 459 - 67 Biosynthesis of coenzyme F430 in methanogenic bacteria . Identification of 15,17(3)-seco-F430-17(3)-acid as an intermediate; Pfaltz A et al.; Coenzyme F430 is a hydroporphinoid nickel complex present in all methanogenic bacteria . It is part of the enzyme system which catalyzes methane formation from methyl-coenzyme M . We describe here that under certain conditions a second nickel porphinoid accumulates in methanogenic bacteria . The compound was identified at 15,17(3)-seco-F430-17(3)-acid . The structural assignment rests on 14C-labelling experiments, fast-atom-bombardment mass spectra, 1H-NMR spectra of the corresponding hexamethyl ester, and ultraviolet/visible spectral comparison with model compounds . In cell extracts and in intact cells of methanogenic bacteria, 15,17(3)-seco-F430-17(3)-acid was converted to F430 . These findings indicate that the new nickel-containing porphinoid is an intermediate in the biosynthesis of coenzyme F430. Biochemistry, 1987 Dec 29, 26(26), 8652 - 8 Antenna organization in green photosynthetic bacteria . 2 . Excitation transfer in detached and membrane-bound chlorosomes from Chloroflexus aurantiacus; Brune DC et al.; The photosynthetic antenna of Chloroflexus aurantiacus includes bacteriochlorophyll (BChl) C740 and BChl a792, both of which occur in chlorosomes, and B808-866 (containing BChl a808 and BChl a866), which is membrane-located (subscripts refer to near-infrared absorption maxima in vivo) . BChl a792 is thought to mediate excitation transfer from BChl c740 to BChl a808 . Lifetimes of fluorescence from BChl c740 and BChl a792 were measured in isolated and membrane-bound chlorosomes in order to study energy transfer from these pigments . In both preparations, the lifetime of BChl c740 fluorescence was at or below the instrumental limit of temporal resolution (about 30-50 ps), implying extremely fast excitation transfer from this pigment . Attempts to disrupt excitation transfer from BChl c740, either by conversion of part of this pigment to a monomeric form absorbing at 671 nm or by partial destruction of BChl a792 by oxidation with K3Fe(CN)6, had no discernible effects on the lifetime of BChl c740 fluorescence . Most (usually greater than 90%) of the fluorescence from BChl a792 decayed with a lifetime of 93 +/- 21 ps in membrane-attached chlorosomes and 155 +/- 22 ps in isolated chlorosomes at room temperature . Assuming that the only difference between these preparations is the occurrence of excitation transfer from BChl a792 to B808-866, a 41% efficiency was calculated for this process . This value is lower than the 60% efficiency of excitation transfer from BChl c740 to B808-866 determined by comparison of fluorescence excitation and absorption spectra of membranes with attached chlorosomes and compares even less favorably with the 100% efficiency of excitation transfer found in whole cells by the same method.(ABSTRACT TRUNCATED AT 250 WORDS) Biochemistry, 1987 Dec 29, 26(26), 8644 - 52 Antenna organization in green photosynthetic bacteria . 1 . Oligomeric bacteriochlorophyll c as a model for the 740 nm absorbing bacteriochlorophyll c in Chloroflexus aurantiacus chlorosomes; Brune DC et al.; Bacteriochlorophyll (BChl) c was extracted from Chloroflexus aurantiacus and purified by reverse-phase high-pressure liquid chromatography . This pigment consists of a complex mixture of homologues, the major component of which is 4-ethyl-5-methylbacteriochlorophyll c stearyl ester . Unlike previously characterized BChls c, the pigment from C . aurantiacus is a racemic mixture of diastereoisomers with different configurations at the 2a chiral center . Diluting a concentrated methylene chloride solution of BChl c with hexane produces an oligomer with absorption maxima at 740-742 and at 460-462 nm . Both the absorption spectrum and the fluorescence emission spectrum (maximum at 750 nm) of this oligomer closely match those of BChl c in chlorosomes . Further support for this model comes from the ability of alcohols, which disrupt BChl c oligomers by ligating the central Mg atom, to convert BChl c in chlorosomes to a monomeric form when added in low concentrations . The lifetime of fluorescence from the 740 nm absorbing BChl c oligomer is about 80 ps . Although exciton quenching might be unusually fast in the in vitro BChl c oligomer because of its large size and/or the presence of minor impurities, this result suggests that energy transfer from the BChl c antenna in chlorosomes must be very fast if it is to be efficient. Acta Odontol Scand, 1987 Dec, 45(6), 429 - 33 The effect of a combination of copper and hexetidine on plaque formation and the amount of copper retained by dental plaque bacteria; Grytten J et al.; Zn++ in combination with hexetidine exerts a synergistic plaque inhibition . Studies in our laboratory on the mechanism of this effect suggested that Cu++ and hexetidine may have a similar combination effect . This hypothesis was tested in vivo on a human test panel in a double-blind crossover study . The amount of Cu++ retained by plaque bacteria in vitro was also evaluated . Seven volunteers rinsed with the solutions for 1 min twice daily for 5 days . The test solutions were H2O, 1.0 mM CuSO4, 2.0 mM hexetidine, and the last two in combination . During the test period no oral hygiene was allowed, and sucrose-containing chewing gum was used to enhance plaque formation . The plaque index scores after rinsing with the combination were significantly (p less than 0.05) lower than those of the other solutions . The effect of hexetidine on Cu++ retention in plaque bacteria was evaluated in plaque samples (n = 3) grown anaerobically overnight in PPLO medium . The bacteria were washed five times, digested in concentrated HNO3, and Cu++ determined by atomic absorption . The presence of hexetidine resulted in a significantly greater amount of Cu++ retained by bacteria at all CuSO4 concentrations . It is suggested that the nonpolar nature of the hexetidine molecule enables Cu++ bound to hexetidine to pass into the bacterial cell . Within the cell, Cu++ can interfere with bacterial metabolism, giving a reduction in plaque growth. Appl Environ Microbiol, 1987 Dec, 53(12), 2992 - 6 Growth determinations for unattached bacteria in a contaminated aquifer; Harvey RW et al.; Growth rates of unattached bacteria in groundwater contaminated with treated sewage and collected at various distances from the source of contamination were estimated by using frequency of dividing cells and tritiated-thymidine uptake and compared with growth rates obtained with unsupplemented, closed-bottle incubations . Estimates of bacterial generation times {(In 2)/mu} along a 3-km-long transect in oxygen-depleted (0.1 to 0.7 mg of dissolved oxygen liter-1) groundwater ranged from 16 h at 0.26 km downgradient from an on-land, treated-sewage outfall to 139 h at 1.6 km and correlated with bacterial abundance (r2 = 0.88 at P less than 0.001) . Partitioning of assimilated thymidine into nucleic acid generally decreased with distance from the contaminant source, and one population in heavily contaminated groundwater assimilated little thymidine during a 20-h incubation . Several assumptions commonly made when frequency of dividing cells and tritiated-thymidine uptake are used were not applicable to the groundwater samples. J Gen Virol, 1987 Dec, 68 ( Pt 12), 3081 - 9 Expression of human papillomavirus type 6 and type 16 capsid proteins in bacteria and their antigenic characterization; Banks L et al.; The L1 and L2 capsid proteins encoded by human papillomavirus types 6 and 16 (HPV-6 and HPV-16) have been synthesized in bacteria . Antisera were raised against the HPV-6 L1- and L2-beta-galactosidase fusion proteins and against an HPV-16 L1 C-terminal peptide which was 14 amino acids long . The HPV-16 L1 peptide antibodies have been shown to be highly reactive with the HPV-16 L1-beta-galactosidase protein but not against the equivalent HPV-6 L1-beta-galactosidase fusion protein . The effectiveness of these antibodies was compared with commercially available antibovine papillomavirus type 1 (BPV-1) antibodies and the results demonstrated that the anti-BPV-1 antibodies reacted well against HPV-6 L1-beta-galactosidase but not against HPV-16 L1-beta-galactosidase . In addition, the L2 portion of the HPV-6 L2-beta-galactosidase fusion protein appeared particularly immunogenic, since antibodies raised against this fusion protein were predominantly reactive with the L2 moiety . The HPV-16 L1 peptide antibodies described here will be preferred reagents for the specific detection of HPV-16 capsid antigens, which may be particularly important in early diagnosis of HPV-16 infection. J Bacteriol, 1987 Nov, 169(11), 5231 - 40 Initiation of chromosome replication in bacteria: analysis of an inhibitor control model; Margalit H et al.; This article contains an analysis of a version of the well-known inhibitor-dilution model for the control of initiation of chromosome replication in bacteria . According to this model, an unstable inhibitor interacts with an initiation primer in a hit-and-destroy fashion to prevent successful initiation; both constituents are presumed to be RNA species that are synthesized constitutively . The model further postulates that the inhibitor interacts cooperatively with the primer, that the inhibitor gene is removed some distance from the origin of replication, and that an eclipse period exists during which the chromosome origin is not able to reinitiate . This unstable-inhibitor version is characterized by four parameters: the inhibitor half-life, the cooperativity index, the location of the inhibitor gene, and the eclipse period; computer simulations are used to study the effect of each of these on the DNA and interdivision time distributions in exponentially growing steady-state cultures . In neither case was any combination of parameter values found that could provide even moderately satisfactory agreement between the simulation results and experimental data . From the examples furnished and the associated discussion, it appears that there are none--that no combination of parameter values exists that can reasonably be expected to produce a significantly better fit than those tested . We conclude that the model in its present form cannot be a valid description of chromosome replication control in bacteria . It is pointed out that this does not necessarily apply to negative initiation control models in general, or even to all inhibitor-dilution systems, merely to the particular ColE1-like mechanism considered here . Nevertheless, recent experimental results, which can only be understood in terms of a very high degree of initiation synchrony within individual cells, offer strong evidence against stochastic models of this kind for the control of chromosome replication. Phys Med Biol, 1987 Nov, 32(11), 1469 - 79 Theory of relative biological effectiveness (RBE) of tritium beta rays: bacteria killing effects of tritiated water; Iwanami S et al.; A new model is applied to bacteria exposed to tritiated water . In this model, the relation between the radiation quality, induction of single- and double-strand breaks in DNA and their repair in vivo can be reasonably described in terms of the microdosimetric distribution and the modification factors for single- and double-strand breaks in DNA . First, a mathematical formulation of RBE of tritium beta rays relative to an arbitrary reference radiation for killing effect on bacteria is derived on this model . Typical theoretical results on the survival curve parameters for bacteria exposed to tritiated water and RBE of tritium beta rays relative to 60Co gamma rays are presented . It is found that RBE of tritium beta rays depends on the ability of the cell to repair DNA damage . The present model is applied to the survival of Escherichia coli Bs-1 exposed to tritiated water and 7 MeV electrons . Although the average LET of tritium beta rays is remarkably higher than that of 7 MeV electrons, the experimental result that RBE of tritium beta rays relative to 7 MeV electrons is close to unity, is reasonably explained by the present model. Microbiologica, 1987 Oct, 10(4), 417 - 20 Phagocytosis of bacteria after exposure to macrophages or lymphocytes; Romano Carratelli C et al.; In our present study we have examined the phagocytosis by polynucleates towards bacteria exposed to macrophages or lymphocytes . Our results show that for almost all the bacterial strains, the contact with lymphocytes determines changes in hydrophobicity correlated to variations in the possibility of being phagocytized and of more significant intracellular killing with respect to bacteria treated with macrophages. Biophys J, 1987 Oct, 52(4), 637 - 47 A variable stoichiometry model for pH homeostasis in bacteria; Macnab RM et al.; The composition of the proton-motive force of a hypothetical bacterial cell of wide pH tolerance is analyzed according to a model whereby the electron transport chain and various proton-linked sodium and potassium ion transporting modes are responsible for the development of the membrane potential and the chemical potentials of the three cations . Simultaneous use of two or more modes employing the same metal cation, but at a different stoichiometric ratio with respect to protons, produces nonintegral stoichiometry; the modes could represent either different devices or different states of a single device . Cycling of the cation, driven by proton-motive force, results . The relative conductances of the various modes are postulated to be pH-dependent . The pattern of potentials that results is qualitatively in accord with current knowledge and may reflect the mechanism of pH homeostasis in bacteria . The membrane potential is outwardly directed (positive inside) at extremely acid pH, becoming inwardly directed as the pH increases; the pH gradient across the membrane is large and inwardly directed (alkaline inside) at acid pH, becoming smaller and eventually inverting at alkaline pH values; the transmembrane potassium gradient is outwardly directed (high concentration inside) at all pH values; the transmembrane sodium gradient is inwardly directed at all pH values, following the pH gradient from acid through neutral pH, but then diverging at alkaline pH. Fertil Steril, 1987 Oct, 48(4), 659 - 63 Comparison of techniques for the selection of bacteria-free sperm preparations; Sun LS et al.; The authors compared the three most commonly used sperm preparation techniques--swim-up, fall-down, and Percoll gradient--for their ability to recover highly motile sperm and minimize bacterial contamination . Eleven human semen samples collected by masturbation were used and run in parallel with the three methods . A semiquantitative bacterial analysis was performed in all samples and results expressed in colony-forming units per milliliter (CFU/ml) . The Percoll gradient technique resulted in an average sperm concentration of 5.81 +/- 4.4 X 10(6) ml, and the average bacterial concentration dropped from 8.66 +/- 12.96 X 10(3) CFU/ml in semen to 0.01 +/- 0.03 X 10(3) CFU/ml . The bacterial count was not significantly different when the raw semen was compared with the swim-up or the fall-down preparations . The authors conclude that the Percoll gradient method yields an adequate sperm concentration, with high motility and improved morphology, while eliminating bacterial contamination. Appl Environ Microbiol, 1987 Sep, 53(9), 2021 - 5 Effect of hydrophobicity of utilization of peptides by ruminal bacteria in vitro; Chen G et al.; When mixed ruminal bacteria were incubated with a pancreatic casein hydrolysate and free amino acids of a similar composition, rates of ammonia production were much greater for peptides than for amino acids . The pancreatic digest of casein was then fractionated with 90% isopropyl alcohol . Hydrophobic peptides which dissolved in alcohol contained an abundance of phenolic and aliphatic amino acids, while the hydrophilic peptides which were precipitated by alcohol contained a large proportion of the highly charged amino acids . The Km values of the mixed ruminal bacteria for each fraction were similar (0.88 versus 0.98 g/liter), but the Vmax of the hydrophilic peptides was more than twice that of the hydrophobic peptides (18 versus 39 mg of NH3 per g of bacterial protein per h) . Pure cultures of ruminal bacteria had a similar preference for hydrophilic peptides and likewise utilized peptides at a faster rate than free amino acids . Since peptide degradation rates differed greatly, hydrophobicity is likely to influence the composition of amino acids passing unfermented to the lower gut of ruminant animals. J Bacteriol, 1987 Sep, 169(9), 4196 - 202 Malate dehydrogenase in phototrophic purple bacteria: purification, molecular weight, and quaternary structure; Tayeh MA et al.; The citric acid cycle enzyme malate dehydrogenase was purified to homogeneity from the nonsulfur purple bacteria Rhodobacter capsulatus, Rhodospirillum rubrum, Rhodomicrobium vannielii, and Rhodocyclus purpureus . Malate dehydrogenase was purified from each species by either a single- or a two-step protocol: triazine dye affinity chromatography was the key step in purification of malate dehydrogenase in all cases . Purification of malate dehydrogenase resulted in a 130- to 240-fold increase in malate dehydrogenase specific activity, depending on the species, with recoveries ranging from 30 to 70% . Homogeneity of malate dehydrogenase preparations from the four organisms was determined by sodium dodecyl sulfate and nondenaturing polyacrylamide gel electrophoresis; a single protein band was observed in purified preparations by both techniques . The molecular weight of native malate dehydrogenases was determined by four independent methods and estimated to be in the range of 130,000 to 140,000 for the enzyme from R . capsulatus, R . rubrum, and R . vannielii and 57,000 for that from R . purpureus . It is concluded that malate dehydrogenase from R . capsulatus, R . rubrum, and R . vannielii is a tetramer composed of four identical subunits, while the enzyme from R . purpureus is a dimer composed of two identical subunits. Eur J Epidemiol, 1987 Sep, 3(3), 216 - 21 Adherence of bacteria to cardiac valve prostheses; Galdiero F et al.; The adherence of bacterial cells to valvular prostheses has been studied . Bacteria were selected on the basis of their surface features (fimbriae, hydrophobicity and specific receptors) . It was found that only strains having fimbriae and high cell surface hydrophobicity adhered to bioprostheses, while they did not adhere to metallic prostheses to any significant extent . Adherence to bioprostheses depended on the exposure time and it was affected by the saline concentration of the suspension medium . Furthermore, different bacterial binding capacity was observed for bioprostheses from different companies. Microbiol Sci, 1987 Sep, 4(9), 267 - 9 Membrane integration of carbohydrate transport in bacteria; Danchin A; A system is described which permits bacteria to couple their intermediary metabolism to the available carbon supply . This system transports carbohydrates vectorially, with concomitant phosphorylation . A phosphorylation cascade is responsible for the coupling with metabolism through control of permeation of other carbon sources and synthesis of modulators such as cAMP. J Immunol, 1987 Sep 1, 139(5), 1658 - 64 Presentation of two epitopes of the preS2 region of hepatitis B virus on live recombinant bacteria; Charbit A et al.; Having developed a genetic procedure to expose a foreign epitope at the surface of Escherichia coli by using the outer membrane LamB protein as a carrier, we apply this procedure to express two distinct portions of the preS2 region of hepatitis B virus: region A, residues 132-145, and region B, residues 153-171 . The resulting hybrid proteins (LamB-preS2 A and LamB-preS2 B) were normally expressed, stable, and still kept most biologic functions of LamB . The corresponding bacterial strains were used directly as immunogens in rabbits and mice . Both viral sequences were found to be immunogenic in the two animal species . With LamB-preS2 A, antibodies induced were able to react with the viral particles and the immobilized peptide . With LamB-preS2 B, the antibodies raised were not able to recognize the immobilized peptide . However, the results suggest that the B epitope, inserted in LamB, was at least as efficient as the corresponding synthetic peptide in raising antiviral antibodies . Thus, epitope presentation with LamB may present advantages for immunization . We also have shown that peptide A is an essential part of the polymerized human serum albumin receptor . These results, which validate further the LamB vector system for epitope presentation, provide information on the two hepatitis B regions expressed. J Biol Chem, 1987 Aug 15, 262(23), 11364 - 8 A native cruciform DNA structure probed in bacteria by recombinant T7 endonuclease; Panayotatos N et al.; T7 endonuclease preferentially cleaves purified supercoiled pBR322 and colE1 plasmids at the single-stranded regions exposed when palindromic sequences assume cruciform structures (Panayotatos, N., and Wells, R.D . (1981) Nature 289, 466-470) . In vivo, however, induction of nuclease synthesis off a cloned gene caused complete degradation of the bacterial DNA but not of the plasmid vector; presumably, single-stranded regions (cruciforms?) on the genome effectively complete for the nuclease with similar sites on the plasmid (Panayotatos, N., and Fontaine, A . (1985) J . Biol . Chem . 260, 3173-3177) . To overcome this competition, we introduced on the plasmid the naturally occurring colE1 palindrome which forms a more stable cruciform in vitro . In addition, we increased the target size (and the T7 endonuclease gene dosage) by raising the copy number of the plasmid 5-fold . Induction of the endonuclease encoded by this new plasmid (pLAT75) resulted not only in degradation of genomic DNA but also in intracellular nicking and linearization of the plasmid . The cleavage site in vivo was mapped at the colE1 palindrome and coincided with the site cleaved specifically in vitro by either T7 or S1 endonuclease only when this palindrome assumes the cruciform structure . These results indicate that cruciform structures exist intracellularly and demonstrate the usefulness of endonucleases as probes of DNA topology in vivo. Eur J Clin Microbiol, 1987 Aug, 6(4), 429 - 31 Cell-wall deficient bacteria in inflammatory bowel disease; Ibbotson JP et al.; Cell wall deficient forms of bacteria were isolated from 40-60% of patients with active inflammatory bowel disease, 15-25% of patients with inactive disease and only 5-7% of controls . The recovery rate from Crohn's disease and ulcerative colitis tissue filtrates did not differ significantly, but was raised in both groups in comparison with controls (p less than 0.01) . It is concluded that a range of such bacteria have a possible aetiological role in inflammatory bowel disease. J Dairy Res, 1987 Aug, 54(3), 413 - 20 Comparison of a simple butterfat agar medium with other media used for isolation and enumeration of lipolytic bacteria from dairy products; Shelley AW et al.; A nutrient agar medium containing 0.1% of a low melting point fraction of butterfat was shown to be suitable for detection, enumeration and isolation of lipolytic bacteria from milk . Bacterial growth was not inhibited by the butterfat and lipolytic reactions were clearly visible and easily interpreted . Lipolytic counts on the butterfat agar compared favourably with lipolytic counts obtained with other commonly used media. Microbiol Sci, 1987 Aug, 4(8), 228 - 37 Experimental evolution of catabolic pathways of bacteria; Ramos JL et al.; Experimental evolution of catabolic pathways offers considerable potential for accelerating the evolution of bacteria able to degrade toxic industrial chemicals, and this may be useful for combatting environmental pollution . The principal strategies that have been successfully followed to evolve useful catabolic routes for aromatic compounds in soil bacteria are analysed. Mol Gen Mikrobiol Virusol, 1987 Aug, (8), 26 - 30 {Characteristics of Methylobacillus flagellatum KT mutants, deficient for phosphoglucoisomerase, an enzyme of the ribulose monophosphate cycle of obligate methylotrophic bacteria}; Kletsova LV et al.; The activities of the key enzymes of ribulose monophosphate cycle for formaldehyde oxidation and assimilation were tested in crude extracts from temperature sensitive mutants of obligatemethylotroph M . flagellatum KT . Tw