Showing papers in "Canadian Journal of Microbiology in 1972"
TL;DR: The results suggest that some volatile components of petroleum that are inhibitory to oil-degrading microorganisms evaporate only very slowly at low temperatures, and thus retard biodegradation.
Abstract: To evaluate the significance of biodegradation in the removal of polluting oil from cold oceans, freshly collected seawater samples were treated with petroleum and were incubated at controlled temp...
157 citations
TL;DR: Various strains of species belonging to the Aspergillus och raceus group (A. ochraceus, A. sclerotiorum, and A. sulphureus) can produce two mycotoxins, ochrato...
Abstract: Various strains of species belonging to the Aspergillus ochraceus group (A. ochraceus, A. sclerotiorum, A. alliaceus, A. ostianus, A. melleus, and A. sulphureus) can produce two mycotoxins, ochrato...
141 citations
TL;DR: Saccharomyces cerevisiae and a riboflavin assay strain of Lactobacillus casei have been propagated anaerobically in mixed culture and a batch and continuous culture techniques were used.
Abstract: Saccharomyces cerevisiae and a riboflavin assay strain of Lactobacillus casei have been propagated anaerobically in mixed culture. Both batch and continuous culture techniques were used. By varying...
126 citations
TL;DR: The formation of pentachloroanisole by methylation frompentachlorophenol by Trichoderma virgatum in liquid cultures was detected using gas chromatography and confirmed by melting point determinati...
Abstract: The formation of pentachloroanisole by methylation from pentachlorophenol by Trichoderma virgatum in liquid cultures was detected using gas chromatography and confirmed by melting point determinati...
104 citations
TL;DR: Bacteriocins from P. syringae, P. phaseolicola, and P. glycinea produced and were sensitive to bacteriocin production, and these groups were classified into 11 groups on the basis of activity spectra against strains of the same species, related and unrelated species, and unrelated genera.
Abstract: Pseudomonas syringae, P. phaseolicola, and P. glycinea produced and were sensitive to bacteriocins. Both solid and liquid media were used in the detection procedures. The bacteriocins were classifi...
86 citations
TL;DR: The dioxygenase produced by Aspergillus flavus that oxidizes quercetin contains 2 moles of copper per mole of enzyme and binds at least 2 mole of substrate.
Abstract: The dioxygenase produced by Aspergillus flavus that oxidizes quercetin contains 2 moles of copper per mole of enzyme and binds at least 2 moles of substrate. The enzyme is not inhibited by sulfhydr...
73 citations
TL;DR: Overproduction of both the hisH and hisF gene products is required for these pleiotropic effects of derepression, and some of their enzymologically inactive forms, may cooperate to inhibit cell division by direct interaction with (a) sensitive cellular site(s).
Abstract: Salmonella typhimurium derepressed for the histidine biosynthetic enzymes form wrinkled colonies at 37 °C on media containing a high (2%) content of metabolizable carbon source. "Wrinkledness" reflects accumulation of multinucleate filamentous cells caused by impaired cell division. At 42 °C, DNA synthesis and nuclear division are impaired. Addition of methionine at 42 °C permits DNA synthesis, nuclear division, and, under some conditions, cell division. However, multinucleate filaments are formed both on high and on low carbon source at 42 °C. The filaments contain nuclei that are peculiarly hypersensitive to inactivation with ultraviolet (uv.) light.Overproduction of both the hisH and hisF gene products is required for these pleiotropic effects of derepression. The hisH and hisF proteins, and even some of their enzymologically inactive forms, may cooperate to inhibit cell division by direct interaction with (a) sensitive cellular site(s).
73 citations
TL;DR: The increase in the duration of the lag phase of growth with decreasing temperatures was expressed with a hyperbolic curve which indicated an infinite lag time at 3.3C, and this relationship between lag time and temperature would provide a relatively rapid method for estimating minimal temperatures of growth.
Abstract: Listeria monocytogenes grew between 3 and 45C. Growth at 10C was at a rate characteristic of psychrophilic bacteria. The increase in the duration of the lag phase of growth with decreasing temperatures was expressed with a hyperbolic curve which indicated an infinite lag time at 3.3C. If this relationship between lag time and temperature is a general phenomenon, it would provide a relatively rapid method for estimating minimal temperatures of growth. Initial rates for oxygen consumption during glucose metabolism and for uptake of the nonmetabolized sugar, 2-deoxyglucose, had temperature coefficients (10–30C) of about 1.5. Growth at 10C increased the rate and the capacity of 2-deoxyglucose uptake by exponential-phase cells. Uptake and incorporation of L-leucine was relatively rapid at 10C but the temperature coefficients were greater than 2. High temperature coefficients (greater than 2.5) for nicotinamide adenine dinucleotide oxidase and lactic dehydrogenase activity in cell-free preparations indicated th...
72 citations
TL;DR: The salient features of this study of the enhancement of bactericidal activity in the hemolymph of the American lobster were increase in response to a number of non-pathogens isolated from the lobster's intestinal tract, and no protection against Gaffkya homari was conferred on the lobster.
Abstract: The salient features of this study of the enhancement of bactericidal activity in the hemolymph of the American lobster were as follows: (a) increase in response to a number of non-pathogens isolated from the lobster's intestinal tract (several pseudomonads, an Achromobacter and Sarcina lutea), (b) one isolate identified as Pseudomonas perolens was used for the bulk of the studies, (c) apparent bactericidal activity of the hemolymph increased severalfold with reduction of the pH of the assay system from the physiological value of 7.6 to a value of 6.0, (d) the extent of the enhancement in vivo was roughly proportional to the concentration of the vaccine, (e) the bactericidal activity's enhancement in vivo was temperature dependent, (f) heat-stability trials indicated the probable presence of more than one bactericidin, (g) the bactericidal principle(s) exists in vivo in an inactive form until activated by material contained within the hemocytes, (h) no protection against Gaffkya homari was conferred on th...
64 citations
TL;DR: The acetylene reduction assay was used to determine nitrogenase activity in a waterlogged soil–straw system and found that Nitrogenase activity was related to the number of nitrogen-fixing Clostridia.
Abstract: The acetylene reduction assay was used to determine nitrogenase activity in a waterlogged soil–straw system. Nitrogenase activity was related to the number of nitrogen-fixing Clostridia. The patter...
62 citations
TL;DR: Intracellular K+ in lysed freeze-thawed cell pastes of the extreme halophile, H. cutirubrum, diffused readily against a concentration gradient during equilibrium dialysis, whereas the intracellular...
Abstract: Intracellular K+ in lysed freeze-thawed cell pastes of the extreme halophile, H. cutirubrum, diffused readily against a concentration gradient during equilibrium dialysis, whereas the intracellular...
TL;DR: An automatic soil-washing apparatus is described which enabled the washing of fungus spores out of large numbers of soil samples simultaneously, and tests of the apparatus indicated that superficial spores were removed from most of the soil particles.
Abstract: An automatic soil-washing apparatus is described which enabled the washing of fungus spores out of large numbers of soil samples simultaneously. Tests of the apparatus indicated that superficial spores were removed from most of the soil particles. This allowed organisms growing in soil as vegetative mycelium to be isolated more readily without the serious competition commonly encountered from organisms sporulating heavily in the soil. Virtually no cross-contamination of soil samples occurred in the multichambered apparatus.
TL;DR: Exogenous carbon and nitrogen sources were necessary for complete swelling (spherical growth) and germ-tube formation from Aspergillus niger spores and under conditions of spore crowding an inhibition became apparent which affec...
Abstract: Exogenous carbon and nitrogen sources were necessary for complete swelling (spherical growth) and germ-tube formation from Aspergillus niger spores. The rate of spherical growth was low at 30°, max...
TL;DR: The identification by gas chromatography of nitrous oxide in the gas phase of cultures containing nitrate and incubated with hydrogen, glucose, or lactate showed that the microbiota was capable of denitrification.
Abstract: A mixed culture of bovine rumen microorganisms was incubated anaerobically, under conditions likely to support growth, with added nitrate and in the presence of several potential hydrogen donors kn...
TL;DR: Fifteen bacterial strains and four molds capable of growth on n-butane were isolated and partially classified, and the bacteria were mostly Arthrobacter sp.
Abstract: Fifteen bacterial strains and four molds capable of growth on n-butane were isolated and partially classified The bacteria were mostly Arthrobacter sp and Brevibacterium sp; among the molds, Pen
TL;DR: It is suggested that calcium and dipicolinic acid are not required for the acquisition of thermoresistance in bacterial endospores but that they are essential to the maintenance of the thermoresistant state and are required for normal germination.
Abstract: Mutants of Bacillus cereus strain T that produce thermoresistant spores which lack dipicolinic acid and have low levels of calcium and manganese have been isolated. The thermoresistant dipicolinate-less spores lose thermoresistance upon storage in distilled water and do not germinate in any liquid medium tested. All spores germinated and produced colonies on G medium agar. It is suggested that calcium and dipicolinic acid are not required for the acquisition of thermoresistance in bacterial endospores but that they are essential to the maintenance of the thermoresistant state and are required for normal germination.
TL;DR: Volatile metabolites produced by eight bacterial species greatly inhibited growth and sporulation of all fungi tested, namely Fusarium oxysporum f.
Abstract: Volatile metabolites produced by eight bacterial species greatly inhibited growth and sporulation of all fungi tested, namely Fusarium oxysporum f. conglutinans, Gelasinospora cerealis, Penicillium...
TL;DR: Using monodispersed cell suspensions, interferon preparations were shown to have both a lethal and a growth-depression effect in the same concentration range as that required for antiviral activity.
Abstract: Using monodispersed cell suspensions, interferon preparations were shown to have both a lethal and a growth-depression effect in the same concentration range as that required for antiviral activity. In addition, synchronized cells treated with interferon respond by delaying their normal uptake of thymidine during S phase until after a period during which new protein is synthesized. Puromycin added during this period prevents both the synthesis of this protein and the subsequent synthesis of DNA.
TL;DR: The results support the hypothesis that SAM is required for a normal tactic response to a chemical stimulus in Escherichia coli.
Abstract: A spontaneous ethionine-resistant mutant of Escherichia coli was found to be nonchemotactic. The mutant had low S-adenosylmethionine (SAM) synthetase activity and a greatly reduced SAM pool. Transd...
TL;DR: Thiobacillus ferrooxidans can derive its energy from the oxidation of copper selenide through this metabolic oxidation process and elemental selenium is deposited.
Abstract: Thiobacillus ferrooxidans can derive its energy from the oxidation of copper selenide. In this metabolic oxidation process, copper goes into solution and elemental selenium is deposited.
TL;DR: Electron microscopy of the two species of Filobasidium show representative basidiomycete dolipores, but in which the pore-occluding material is a flattened plate with dark edges and a lighter center.
Abstract: Electron microscopy of the two species of Filobasidium show representative basidiomycete dolipores, but in which the pore-occluding material, instead of being a homogenous, electropaque, dome-shape...
TL;DR: Several periphytic marine bacterial cultures were examined for their content of hydrolytic enzymes and quantitative assays were done for extracellular and intracellular proteinase, phosphatase, estera...
Abstract: Several periphytic marine bacterial cultures were examined for their content of hydrolytic enzymes. Quantitative assays were done for extracellular and intracellular proteinase, phosphatase, esterase, β-glucosidase, and four polysaccharide hydrolase activities. While some of the enzymes were released extracellularly by growing cells, the greatest amounts of proteinase, esterase, phosphatase, and β-glucosidase were located in the cells and released by mechanical breakage or by cell autolysis. Substantial amounts of proteinase were found in washed cell envelopes of the bacteria. All of the bacteria showed some enzymatic activity against one or more of the algal and microbial acid polysaccharides tested. Enzymes active against these polyanions were found either extracellularly or in cell extracts, depending on the culture concerned. Partial lysis of cell envelopes from two of the periphytes was produced by extracellular or intracellular enzyme mixtures. The ecological importance of bacterial hydrolases and t...
TL;DR: The results suggest that carbohydrate dissimilation by extremely halophilic bacteria may be more common than previously thought and that the apparent rarity of carbohydrate-metabolizing halophiles may be an artifact of the isolation procedures used.
Abstract: Four previously unrecognized strains of extremely halophilic bacteria that utilize carbohydrates have been isolated. Gas production proved an unreliable index of carbohydrate metabolism; therefore, carbohydrate utilization was measured by determining acid formation and sugar disappearance during growth. By these procedures, carbohydrate utilization was readily detected. The results suggest that carbohydrate dissimilation by extremely halophilic bacteria may be more common than previously thought and that the apparent rarity of carbohydrate-metabolizing halophiles may be an artifact of the isolation procedures used.
TL;DR: Temperate bacteriophages of diverse morphology were demonstrated by electron microscopy in toxigenic cultures of Clostridium botulinum, and a provisional grouping of toxigenics types into four categories is suggested, based mainly upon associated phage patterns.
Abstract: Temperate bacteriophages of diverse morphology were demonstrated by electron microscopy in toxigenic cultures of Clostridium botulinum. The 41 strains examined included 23 type E and multiple representatives of all other types. Cultures induced with mitomycin-C generally gave better yields, but phages were also demonstrable in untreated cultures.A provisional grouping of toxigenic types into four categories is suggested, based mainly upon associated phage patterns. Group 1 comprises types A, B, and F (all proteolytic), many of whose cultures showed an icosahedral contractile phage; others contained a "bullrushy" phage with elongated head and long flexible tail; some strains yielded both. Group 2, types B and F (non-proteolytic), were associated with icosahedral contractile phages; the latter also had an octahedral flexible phage. Group 3, types C and D, yielded conspicuously large phages with octahedral heads and very long sheathed tails. One type C strain produced a long-tailed icosahedral phage. Type E ...
TL;DR: Studies on the oxygen requirements of aerobic psychrotolerant bacteria showed that the oxygen concentration of the atmosphere can be lowered to 2% without noticeably inhibiting growth rate.
Abstract: Studies on the oxygen requirements of aerobic psychrotolerant bacteria showed that the oxygen concentration of the atmosphere can be lowered to 2% without noticeably inhibiting growth rate. Tests w...
TL;DR: At least one species from each family of yeasts was found to produce ascorbic acid, and a Roe and Kuether chromogen derived from such enediols could be isolated from 23 of the species.
Abstract: Forty-two species of yeast were examined for their ability to produce enediols of the ascorbic acid class. A Roe and Kuether chromogen derived from such enediols could be isolated from 23 of the species. The chromogen from four yeasts was further identified by infrared (i.r.) spectrophotometry as being derived from ascorbic acid. At least one species from each family of yeasts was found to produce ascorbic acid.
TL;DR: Vacuum-packaging of fresh beef in a gas-impermeable film reduced the growth rates of most incident bacteria, favored the development of lactobacilli, and markedly increased the odor and color shelf life during storage at 5 °C.
Abstract: Vacuum-packaging of fresh beef in a gas-impermeable film (vinyldene chloride – vinyl chloride copolymer), as compared to packaging in a gas-permeable film (polyvinyl chloride), reduced the growth rates of most incident bacteria (lower total aerobic and anaerobic counts), favored the development of lactobacilli, and markedly increased the odor and color shelf life during storage at 5 °C. The growth rate of both aerobes and anaerobes on meat packaged in vinyldene chloride (VC) film was about 1/8 of that of meat packaged in the polyvinyl chloride (PVC) film. The flora of VC-packaged samples consisted largely of lactobacilli (50–70%) while that of PVC-packaged samples consisted mostly of pigmented pseudomonads and M. thermosphactum (collectively 60%). Exposure of VC-packaged samples to air changed the microflora to one resembling that of samples initially packaged in PVC film. VC-packaged meat did not undergo noticeable changes in odor or color even after 32 days of storage while meat stored in PVC developed ...
TL;DR: Inhibition of carotenoid pigments by 10−6 M diphenylamine decreased photoreactivation efficiency, and the carotene pigments have been implicated in an energy-transfer role to augment the photore activation mechanism.
Abstract: Extremely halophilic bacteria are able to survive in a natural environment exposed to high doses of ultraviolet irradiation. One such organism, Halobacterium cutirubrum, has been characterized to p...
TL;DR: Prototheca, which has been referred to as an achlorophyllous Chlorella, is now for the first time associated nutritionally with Chloreella protothecoides, providing circumstantial evidence that Prototheca and C. prototheCOides are related.
Abstract: Prototheca, which has been referred to as an achlorophyllous Chlorella, is now for the first time associated nutritionally with Chlorella protothecoides. Prototheca spp. and C. protothecoides share a requirement for thiamine and lack the ability to assimilate nitrate. This provides circumstantial evidence that Prototheca and C. protothecoides are related and excludes the other morphologically similar Chlorella.
TL;DR: The known diminution in penicillin formation by added lysine is thought to occur via feedback regulation of the lysin biosynthetic pathway, thus depleting the cells of α-aminoadipic acid, a precur...
Abstract: The known diminution in penicillin formation by added lysine is thought to occur via feedback regulation of the lysine biosynthetic pathway, thus depleting the cells of α-aminoadipic acid, a precur...