Showing papers in "Canadian Journal of Microbiology in 1988"
278 citations
TL;DR: The synthesis of extracellular polysaccharides has been recognized in certain bacterial cultures since the 1880s and much effort has been directed towards elucidating their structure in pathogenic bacteria and in enteric organisms in particular.
Abstract: The synthesis of extracellular polysaccharides has been recognized in certain bacterial cultures since the 1880s. It is now apparent that a wide range of bacteria produce these polymers and an equa...
265 citations
TL;DR: The dominance of inhibitor-producing lactobacilli on the urogenital epithelium and the ability of these organisms to interact closely with uropathogens would constitute an important host defense mechanism against infection.
Abstract: Previous investigations have shown that certain strains of lactobacilli can competitively exclude uropathogens from attaching to uroepithelial cells and from causing urinary tract infection in anim...
255 citations
TL;DR: Results show that lactobacilli therapy, using carefully selected organisms to treat patients who are closely followed, may be effective in the prevention of recurrent urinary tract infections.
Abstract: Urinary tract infections remain a common problem, particularly in the female population. New methods are required to manage recurrent cystitis, and extensive research to date has suggested that restoration of the lactobacilli flora of the urogenital tract may prevent these infections. In this study, five females suffering from recurrent urinary tract infections were treated twice weekly with intravaginal and perineal implantation of Lactobacillus casei GR-1. These organisms colonized the epithelium and prevented the emergence of coliform bacteria in most instances, but did not appear to affect enterococcal colonization. In vitro studies showed that L. casei GR-1 inhibited the growth of the coliforms but did not inhibit enterococci. Each of the five patients had infection-free periods ranging from 4 weeks to 6 months. The treatment was well tolerated, had no side effects, led to an improved well-being, and was preferred to antibiotic treatment by all of the patients. These human studies, albeit of a limite...
189 citations
TL;DR: Pseudomonas sp.
Abstract: Enrichment cultures were established with the aromatic fraction of a crude oil and screened for aromatic-degrading pseudomonads, using a sprayed plate technique. One isolate identified as Pseudomon...
159 citations
TL;DR: The shape of bacteria is determined by the wall which surrounds the protoplast, which resides in diverse chemical and organizational forms and is of fundamental importance for several aspects of cellular life and growth.
Abstract: The shape of bacteria is determined by the wall which surrounds the protoplast. This enveloping structure resides in diverse chemical and organizational forms and is of fundamental importance for several aspects of cellular life and growth. This article discusses these general aspects and serves as an introduction to the journal issue and to the more specific papers which follow in the section.
150 citations
TL;DR: The ability of L. casei GR-1 and possibly other lactobacilli strains to produce inhibitors of uropathogenic bacteria may have clinical importance and significance in the microbial ecology of the urogenital tract.
Abstract: Recent studies have shown that certain lactobacilli strains have the ability to interfere with the adherence and growth of uropathogenic bacteria. This interaction is believed to be important in th...
150 citations
138 citations
TL;DR: Bacterial surface hydrophobicity can be altered significantly through exposure to subinhibitory concentrations of antibiotics, surfactants, lectins, etc. and the effect of these changes on subsequent phagocytic ingestion is discussed.
Abstract: The role that bacterial surface hydrophobicity (surface tension) plays in determining the extent of adhesion of polymer substrates and phagocytic ingestion is reviewed. The early attachment phase i...
135 citations
128 citations
TL;DR: The thermal stability of reassociated DNA strands is useful in delineating genomic species and some medically important genomic species previously had been split into several nomenspecies on the basis of a few characteristics whereas some environmental genomic species had been lumped into unidentifiable aggregates.
Abstract: The reassociation properties of DNA provide invaluable taxonomic tools. Different methods may give different reassociation values. However, the thermal stability of reassociated DNA strands (a measurement that seems independent of method) is useful in delineating genomic species. Although many phenotypically defined species have been confirmed by DNA reassociation, some medically important genomic species previously had been split into several nomenspecies on the basis of a few characteristics whereas some environmental genomic species had been lumped into unidentifiable aggregates. It might take some time before the nomenclature can be adapted to new taxonomic findings.
TL;DR: Seven bacterial strains belonging to the genus Bacillus were isolated from rhizosphere soil of spring wheat (Triticum aestivum L.) cv.
Abstract: Seven bacterial strains belonging to the genus Bacillus were isolated from rhizosphere soil of spring wheat (Triticum aestivum L.) cv. Katepwa. The plants from which the microorganisms were isolated were collected from a field that had been continuously cropped with spring wheat for the past 27 years. Cultivar Katepwa had been grown for the last 5 years whereas the closely related cv. Neepawa had been cultivated for the 12 previous years. When tested as single strain inoculum in a sterilized sand and Turface (montmorillonite clay) mix, six of seven isolates promoted root growth of cv. Katepwa spring wheat (p < 0.05), but none promoted that of cv. Neepawa or of the more distant genetic relative cv. HY320. Shoot height was also increased in cv. Katepwa (p < 0.1), but shoot weight of all three cultivars was unaffected by inoculation. Consequently, the root to shoot weight ratio of cv. Katepwa was also greater because of bacterization. These results indicate that beneficial bacteria may be isolated by employi...
TL;DR: The proximity of the lymphatic and blood circulatory systems to the M cell follicle makes this a probable route for systemic spread of Campylobacter jejuni.
Abstract: M cells in the Peyer's patches may facilitate transport of pathogens such as Campylobacter jejuni from the intestine. We evaluated this hypothesis by using electron microscopy to examine Peyer's pa...
TL;DR: In an extension of the previous studies demonstrating the ability of reversibly and irreversibly adhering bacteria to metabolize surface-bound organic substrates, this work directly demonstrated cell reprograming in E. coli.
Abstract: In an extension of our previous studies demonstrating the ability of reversibly and irreversibly adhering bacteria to metabolize surface-bound organic substrates, we have directly demonstrated cell...
TL;DR: Introduction 407 Ultrastructure 409 Relatedness 410 Functions 411 Conclusions 411
Abstract: Introduction 407 Ultrastructure. .407 Chemical composition. .409 Relatedness 410 Functions 411 Conclusions 411
TL;DR: Of five regions in Ontario that were examined, the eastern region had a significantly higher incidence rate of Listeria species than the western, northern, or northwestern regions and there was a significantly lower incidence rate in winter than in the other three seasons.
Abstract: Raw milk samples from bulk tanks in Ontario were analyzed for the presence of Listeria species The overall incidence of Listeria species in raw milk was 124% Listeria innocua was most frequently isolated and was found in 97% (43/445) of the raw milk samples, while L monocytogenes and L welshimeri were each found in 13% (6/445) of the samples No other species of Listeria was found Of five regions in Ontario that were examined, the eastern region had a significantly higher incidence rate of Listeria species than the western, northern, or northwestern regions There was also a significantly lower incidence rate of Listeria species in winter than in the other three seasons A comparison of several cold enrichment and shortened enrichment procedures demonstrated that no single procedure was totally satisfactory in isolating Listeria species
TL;DR: An ammonium-oxidizing chemolithotroph has been isolated from Alaskan waters that is different from any of the previously described species, and DNA–DNA hybridization results indicate that the isolate is a new species; the name Nitrosomonas cryotolerans is proposed.
Abstract: An ammonium-oxidizing chemolithotroph has been isolated from Alaskan waters that is different from any of the previously described species. The cells are 2.0–4.0 μm long and 1.2–2.2 μm wide. The ce...
TL;DR: The high frequency of isolation in both the sandhill crane and migratory ducks indicated that these bird populations may play a significant role in the dissemination of the bacterium.
Abstract: Migratory ducks, Canada geese, and sandhill crane from the Pacific North American Flyway have been screened for Campylobacter spp. Samples (298) from these birds were examined and the incidence of ...
TL;DR: The flagellar filament and its role in physiology, medicine and sport.
Abstract: The flagellar filament . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 452 Flagella isolation and composition. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ,452 Serological analyses of flagella. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ,453 Properties of flagellins. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ,454 Concludingremarks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 455
TL;DR: Lowering the amount of indoxyl beta-D-glucoside to 60 mg/L (1/10 the recommended concentration) reduced the cost of this medium without affecting its sensitivity.
Abstract: Medium m-CP, designed for the isolation of Clostridium perfringens from water samples, contains indoxyl β-D-glucoside, an expensive chemical that is present at a high concentration in this medium. ...
TL;DR: The results show that cation binding is governed by strong stereochemical constraints and could induce a "locked" conformation of the receptor; this conformation is the only one capable of binding phosphomannan strongly enough to make cell adhesion possible.
Abstract: Yeast flocculation is governed by the competition between electrostatic repulsion (nonspecific interaction) and polysaccharide-protein bonds (specific interaction) The electrical surface potential, which is mainly due to phosphodiester linkages (of the cell wall phosphomannan), maintains the cells dispersed Polysaccharides and proteins of the cell surface can readily penetrate the potential barrier and may establish specific bonds The specific inhibition of flocculation by various mannosyl derivatives suggested that the protein receptor binds to the group Man alpha----3 Man alpha----PO4- ----6 Man alpha----2 Man alpha of phosphomannan Calcium, which is required for flocculation, could act as a bridge between the negatively charged groups of phosphomannan and those of the protein receptor The role of calcium, however, cannot be restricted only to charge neutralization because other divalent cations inhibit flocculation; our results show that cation binding is governed by strong stereochemical constraints Studies on protein-polysaccharide interactions have shown that electrical charges may remain uncompensated at short distance, but can be stabilized by hydrogen bonds Calcium could induce a "locked" conformation of the receptor; this conformation is the only one capable of binding phosphomannan strongly enough to make cell adhesion possible
TL;DR: Analytical gel electrophoresis and isoelectric focusing demonstrated that the acetyl xylan esterase activity of S. reesei RUT C-30 behaved like a catabolite repression resistant mutant and produced higher enzyme levels than the QM 9414 strain on all carbon sources examined.
Abstract: Activity of acetyl xylan esterase, an enzyme that removes acetyl groups from acetyl xylan, was coproduced with that of endoxylanase and endoglucanase in two Trichoderma reesei strains and one Schizophyllum commune strain. The levels of activity of extracellular enzymes were measured during the course of cultivation on different carbon sources. The highest activity levels of acetyl xylan esterase were produced by T. reesei QM 9414 in a xylan plus cellulose medium and by S. commune in a cellulose medium. Both strains produced low levels of acetyl xylan esterase activity in glucose, xylose, and cellobiose media. Schizophyllum commune also produced low levels of acetyl xylan esterase activity in xylan and acetyl xylan media. Trichoderma reesei RUT C-30 behaved like a catabolite repression resistant mutant and produced higher enzyme levels than the QM 9414 strain on all carbon sources examined. Analytical gel electrophoresis and isoelectric focusing demonstrated that the acetyl xylan esterase activity of S. co...
TL;DR: Seed treatment with conidia of rhizosphere-competent mutants of Trichoderma harzianum reduced the incidence of preemergence damping-off of barley, cucumber, pea, radish, and tomato induced by Pythium ultimum, and wild-type parents of these mutants were less effective in control.
Abstract: Seed treatment with conidia of rhizosphere-competent mutants of Trichoderma harzianum reduced the incidence of preemergence damping-off of barley, cucumber, pea, radish, and tomato induced by Pythi...
TL;DR: When grown in static culture it appears as if Thermomyces lanuginosus has a biphasic secretion of the extracellular starch-degrading activity, which could be due to the presence of at least two different amylases.
Abstract: When grown in static culture it appears as if Thermomyces lanuginosus has a biphasic secretion of the extracellular starch-degrading activity This could be due to the presence of at least two diff
TL;DR: Heterotrophic plate counts at 20 and 35 degrees C were low in the freshly treated water leaving the plants, but bacterial regrowth was observed in both distribution systems at all sampling sites.
Abstract: The microbial flora of the water produced by two water filtration plants and their drinking water distribution system were evaluated: the Pont-Viau (PV) and the Repentigny (RE) water filtration pla...
TL;DR: The xylose-fermenting yeasts Pichia stipitis, Candida steatolytica, and Candida shehatae were subjected to fermentations in synthetic media containing mixtures of glucose and Xylose, and repression ofxylose uptake by glucose was observed.
Abstract: The xylose-fermenting yeasts Pichia stipitis, Candida steatolytica, and Candida shehatae were subjected to fermentations in synthetic media containing mixtures of glucose and xylose. In all cases, repression of xylose uptake by glucose was observed, although the extent of repression was different with each yeast. While Candida shehatae was found to utilize xylose effectively in the presence of approximately 5% (w/v) glucose, Candida steatolytica could only utilize xylose when the glucose concentration was below 3% (w/v), and Pichia stipitis required the glucose concentration in the medium to be below 2% (w/v) before significant xylose utilization occurred.
TL;DR: Thermodynamic analysis of the degradation of selected compounds showed that aerobic and denitrifying processes are heat driven (large enthalpy change) and analysis of published data strongly suggests that the movement of succinate, acetate, and possibly longer chain fatty acids is carrier mediated.
Abstract: Thermodynamic analysis of the degradation of selected compounds showed that aerobic and denitrifying processes are heat driven (large enthalpy change). Owing to the smaller enthalpy changes, other anaerobic processes depend more on the entropy flow of chemical substances exchanged with the environment. This results in partial degradation of the substrate and the excretion of end products which have a high free-energy content. This creates niches for organisms to use these end products as energy sources. Mechanistically, the efflux of end products can be used to conserve energy by coupling the efflux with the translocation of protons or other ions. Analysis of published data strongly suggests that the movement of succinate, acetate, and possibly longer chain fatty acids is carrier mediated. Hypothetical calculations showed that these compounds can accumulate to high internal concentrations relative to extracellular concentrations, which suggests that the efflux of these compounds can generate a proton-moti...
TL;DR: The results are consistent with the hypothesis that antifungal phenols, produced by the gut bacterial flora, are responsible for the fungitoxic activity in the gut of the desert locust.
Abstract: Antifungal compounds have been found in gut fluid and aqueous faecal extracts from parasite-free and conventional desert locusts (Schistocerca gregaria), but not from germ-free locusts. These compo...