Showing papers in "Antonie Van Leeuwenhoek International Journal of General and Molecular Microbiology in 1976"
TL;DR: The possible taxonomic use of the colour reaction with Diazonium Blue B salt as an affinitive characteristic of the Cryptococcales is discussed.
Abstract: Seventy yeast strains, representative of twenty-six ascogenous genera, four saprobic hemibasidiomycetous genera and thirteen genera of the Cryptococcales were tested for their reaction with the stabilized aromatic diazonium compound, Diazonium Blue B salt. An aqueous, buffered solution of this compound gave a characteristic red colouration with the colonies of the hemibasidiomycetous species and those Cryptococcales characterized by the hemibasidiomycetous cell-wall type. The characteristic colour reaction was not observed with colonies of either the ascomycetous yeasts or those Cryptococcales characterized by the ascomycetous cell-wall type.
99 citations
TL;DR: The course of the biological oxidation of ethylene by soil was dependent on the type of soil used as well as on other factors as discussed by the authors, as evidenced from an increase in oxidation rate, the ethylene-consuming microorganisms in soil could grow at the expense of the gas, even when the gas was present at concentrations of 50 ppm or less.
Abstract: The course of the biological oxidation of ethylene by soil was dependent on the type of soil used as well as on other factors. As evidenced from an increase in oxidation rate, the ethylene-consuming microorganisms in soil could grow at the expense of ethylene, even when the gas was present at concentrations of 50 ppm or less. Five strains of bacteria strongly resembling each other were isolated from different soils. These pleomorphic, gram-positive, acid-fast, obligate aerobic, ethylene-oxidizing bacteria grew also on saturated alkanes and on ordinary carbon sources. An apparent Km for ethylene of approximately 40 ppm was estimated for whole-cell suspensions of strain E20 by following the disappearance of the gas from the atmosphere.
91 citations
TL;DR: The minimum inhibiting concentrations (MIC) of Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD) for staphylococci and streptococci in broth are in the range of 1–5 μg/ml, both compounds are also bactericidal.
Abstract: The minimum inhibiting concentrations (MIC) of Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD) for staphylococci and streptococci in broth are in the range of 1–5 μg/ml. In the same range, both compounds are also bactericidal. In media containing 4% serum or 5% blood the antibacterial activity is strongly reduced (MIC 50μg/ml). Gram-negative bacteria are resistant to THC and CBD.
78 citations
TL;DR: A new genus and species, Prosthecobacterfusiformis, is proposed for the fusiform caulobacters, which have been isolated from freshwater sources and exhibit a dimorphic life cycle of motile, non-stalked daughter cells and immotile, stalked mother cells.
Abstract: Four strains of heterotrophic, fusiform caulobacters have been isolated from freshwater sources. A single prostheca extends from one pole of mature cells, and cells attach to various substrata by means of a holdfast located at the distal tip of the appendage. Thus, superficially these bacteria bear a strong resemblance to bacteria in the genus Caulobacter. However, unlike Caulobacter these bacteria do not exhibit a dimorphic life cycle of motile, non-stalked daughter cells and immotile, stalked mother cells. Instead both mother and daughter cells are immotile, and at the time of cell separation the daughter cells are essentially identical mirror-image replicas of the mother cell. In addition, the prosthecae of these fusiform caulobacters do not have crossbands, they are somewhat wider than the stalks of Caulobacter and the pseudostalks of Asticcacaulis, and they terminate in a bulbous tip. The deoxyribonucleic acid (DNA) base composition ranges from 54.6-60.1, well below the 62-67 range for the genus Caulobacter. Based upon these and other differences a new genus and species, Prosthecobacter fusiformis, is proposed for the fusiform caulobacters.
45 citations
TL;DR: Fructose-6-phosphate phosphoketolase was purified from type strains of two species of the genus Bifidobacterium: B. globosum and B. dentium, showing very different optimum pH range, metal activator and molecular weight; outstanding difference was found in the substrate specificity.
Abstract: Fructose-6-phosphate phosphoketolase was purified from type strains of two species of the genus Bifidobacterium: B. globosum and B. dentium. The first species has a preferred “animal” habitat, like feces of animals and rumen of cattle; the latter is harboured in “human” habitats, like feces and dental caries of man. Two electrophoretic types of phosphoketolase (F6PPK) were previously distinguished and called “animal” and “human” type according to the habitat of the bifid organism. The purified preparations of these two phosphoketolases displayed very different optimum pH range, metal activator and molecular weight; outstanding difference was found in the substrate specificity: the enzyme from B. globosum was able to split xylulose-5-P as well as fructose-6-P, whereas the phosphoketolase from B. dentium appeared to be specific for fructose-6-P.
42 citations
38 citations
TL;DR: Cell-free extracts from Aspergillus flavus catalyzed the synthesis of chitin from UDP-GlcNAc, with most of the activity associated with membrane-rich fractions whereas no activity was detected in the cell walls.
Abstract: Cell-free extracts from Aspergillus flavus catalyzed the synthesis of chitin from UDP-GlcNAc. Most of the activity was associated with membrane-rich fractions whereas no activity was detected in the cell walls. Chitin synthetase was activated by fungal acid proteases; animal and plant proteases destroyed it. Upon incubation at 0 C and 28 C chitin synthetase was inactivated, probably by the action of proteases present in the particulate preparations. Maximal activity was obtained at pH 6.6–7.1 and 15 C. Arrhenius plot showed a biphasic curve with the transition at 7 C. E values were 3300 Kcal/mole above this temperature and 15500 Kcal/mole below it. The enzyme was activated by GlcNAc and required a divalent metal, the most active being Mg++. By plotting v vs UDP-GlcNAc concentration a sigmoidal curve was obtained. Km calculated at high substrate concentrations was 20mm. Chitin synthetase was competitively inhibited by polyoxin D (Ki 6.5 μm) and UDP (Ki 1.35mm), the latter giving complex kinetics.
38 citations
TL;DR: In an attempt to improve by hybridisation strains of pure-culture wine yeasts it could be shown, that of the seven strains used five are homothallic.
Abstract: In an attempt to improve by hybridisation strains of pure-culture wine yeasts it could be shown, that of the seven strains used five are homothallic. Evidence is presented suggesting that the remainder are also homothallic.
37 citations
TL;DR: Although presenting the physiological characteristics of a pseudomonad, the organism described has been placed in the genus Flavobacterium because of its pigmentation and its low GC percentage.
Abstract: A previously undescribed denitrifying bacterium was isolated from soil. The cells are small gram-negative rods, asporogenous, and non-motile. Colonies become yellow after long exposure to light. This colouring is due to the production of a carotenoid pigment. The organism shows no fermenting activity, and grows only in the presence of one of the following electron acceptors: NO2, N2O, and O2. It does not reduce nitrate. It gives a positive oxidase test and has a cytochrome c and catalase. It requires no growth factors, is a chemoorganotroph and uses only sugars as carbon and energy supply. The DNA base composition is 40.8 moles percent GC. Although presenting the physiological characteristics of a pseudomonad, the organism described has been placed in the genus Flavobacterium because of its pigmentation and its low GC percentage.
37 citations
TL;DR: Interestingly, m-nitrophenol, known for its resistance to biodegradation because of meta substitution, was decomposed by Bacillus sp.
Abstract: Two bacterial isolates from parathion-amended flooded soil, Pseudomonas sp and Bacillus sp, were examined for their ability to decompose nitrophenols Uniformly labelled 14C-p-nitrophenol was metabolized by both bacteria, 14CO2 and nitrite being end products A substantial portion (23% for Pseudomonas sp and 80% for Bacillus sp) of radioactivity applied as p-nitrophenol was accounted for as 14CO2 at the end of a 72-h period; 8 to 16% remained in the water phase after solvent extraction Pseudomonas sp produced nitrite also from 2,4-dinitrophenol, but only after a lag, and not from o- and m-nitrophenols Interestingly, m-nitrophenol, known for its resistance to biodegradation because of meta substitution, was decomposed by Bacillus sp, resulting in the formation of nitrite and phenol; o-nitrophenol and 2,4-dinitrophenol resisted degradation by this bacterium
36 citations
TL;DR: The degradation of neoagarotetraose and neoagarobiose by Cytophaga flevensis was investigated and evidence was obtained that these activities were due to different enzymes.
Abstract: The degradation of neoagarotetraose and neoagarobiose by Cytophaga flevensis was investigated The organism possesses an enzyme that hydrolyzes the tetramer by cleavage of its central β-galactosidic linkage The product of this reaction, neoagarobiose, is further hydrolyzed enzymatically to d-galactose and 3,6-anhydro-l-galactose Both enzyme activities were localized in the cytoplasm Attempts were made to partially purify the respective enzymes and although at 30–40-fold purification was achieved, the final preparation contained both neoagarotetra-ase and neoagarobiase activities Evidence was obtained that these activities were due to different enzymes Neoagarotetra-ase is highly specific for oligosaccharides containing neoagarobiose units; the rate of hydrolysis is greatest with neoagarotetraose It cannot hydrolyze pyruvated neoagarotetraose Optimal conditions for its activity were pH 70 and 25 C Neoagarobiase hydrolyzes only neoagarobiose and neoagarobiitol and optimal conditions for activity were pH 675 and 25 C Both enzymes were inhibited by Ag+, Hg2+ and Zn2+ ions and by p-CMB, which indicates that thiol groups are present in their active centres Both enzymes were induced by neoagaro-oligosaccharides and melibiose and were repressed when glucose was added to the medium Neoagarobiase was also induced by d-galacturonic acid In continuous culture, the rate of enzyme production was maximal at a dilution rate of 01 h-1
TL;DR: The ethylene-oxidizing strain E20 was grown on different carbon sources and from a comparison of the specific activities of isocitrate lyase and malate synthetase in different extracts it was concluded that the glyoxylate cycle was involved in the metabolism of Ethylene, indicating that acetyl-CoA is a metabolite of ethylene catabolism.
Abstract: The ethylene-oxidizing strain E20 was grown on different carbon sources to obtain information on the metabolism of ethylene from simultaneous adaptation studies and from measurements of specific activities of enzymes in cell-free extracts. From the simultaneous adaptation studies it was concluded that ethylene oxide is a product of ethylene catabolism. The bacterium was also able to grow on the epoxide. From a comparison of the specific activities of isocitrate lyase and malate synthetase in different extracts it was concluded that the glyoxylate cycle was involved in the metabolism of ethylene, indicating that acetyl-CoA is a metabolite of ethylene catabolism. The sequence of reactions leading from ethylene oxide to acetyl-CoA could not be established from the simultaneous adaptation experiments and the enzyme activities in extracts.
TL;DR: The nature of the endogenous reserves of Saccharomyces cerevisiae was examined with respect to conditions of growth, specifically extremes of oxygen tension and carbon source and the greatest effect of growth conditions on the chemical composition of the cells was on their fatty acid and sterol content.
Abstract: The nature of the endogenous reserves of Saccharomyces cerevisiae was examined with respect to conditions of growth, specifically extremes of oxygen tension and carbon source. Cells were grown in batch culture at 30 C under aerobic conditions on a galactose or glucose carbon source and under anaerobic conditions on glucose. The greatest effect of growth conditions on the chemical composition of the cells was on their fatty acid and sterol content. Cells grown under both aerobic and anaerobic conditions mobilised concurrently protein, glycogen, trehalose and fatty acids during a period of 72 hours' starvation under aerobic conditions. The viability of both types of the aerobically grown cells declined to 75% during this period and was not influenced by the initial fatty acid and sterol content of the cells. Cells grown anaerobically showed a more rapid decline in viability which was only 17% after 72 hours' starvation. This loss of viability was not due to a lack of available endogenous reserves but was probably due to an impaired membrane function caused by a deficiency of sterols and unsaturated fatty acids.
TL;DR: The high rate of respiration of C. albicans in the presence of inhibitors for three sites of electron transport in the conventional oxidative pathway and the inhibition of this respiration by SHAM indicate an alternate oxidative pathway in this organism which crosses the conventional one at cytochrome b.
Abstract: Usual concentrations of antimycin A, rotenone and EDTA, individally or in combination, reduced aerobic growth rate and cell yield of Candida albicans to about half its normal level and to about the levels of previously-described acetate-negative, cytochrome-complete and aa3-deficient variants which were little affected by the inhibitors. Anaerobic conditions (not affected by antimycin A) reduced growth rate and cell yield of all cultures-including that of a nonrespiring aa3, b-deficient mutant-to low, equal levels. Antimycin A but not rotenone prevented growth of the normal strain on ethanol medium. Cyanide and antimycin A blocked most of the respiration of the normal strain and cytochrome-complete variant, but did not affect that of the cytochrome aa3-deficient mutant. Rotenone and EDTA did not affect respiration of any of the cultures. SHAM blocked cyanide- and antimycin A-insensitive respiration and prolonged the lag phases of the three respiring cultures, especially in the presence of antimycin A, but alone increased oxygen-uptake rate of the cytochromecomplete cultures while curtailing that of the cytochrome aa3-deficient mutant. Resting cells, especially wild-type, grown in medium containing antimycin A exhibited lowered oxygen-uptake rate, which was increased upon the addition of cyanide or antimycin A. Antimycin A stimulated, but cyanide inhibited, respiration of cytochrome-complete cultures grown in the presence of rotenone but did not affect that of the cytochrome aa3-deficient mutant. SHAM inhibited respiration of all antimycin A- or rotenone-grown cultures. The high rate of respiration of C. albicans in the presence of inhibitors for three sites of electron transport in the conventional oxidative pathway, the inhibition of this respiration by SHAM and its loss by the absence of cytochrome b, indicate an alternate oxidative pathway in this organism which crosses the conventional one at cytochrome b.
TL;DR: A wide range of tolerance to Li+ has been found among 12 different yeasts, and for given extracellular conditions, intracellular Li+ concentrations are lower in the more tolerant yeast strains.
Abstract: A wide range of tolerance to Li+ has been found among 12 different yeasts. Concentrations that do not allow long-term growth also arrest growth of an actively growing culture within 2–5 h. At the same concentrations protein and RNA synthesis are inhibited with little or no lag period (<50 min) but respiration is not affected at these concentrations. Lower concentrations that do not inhibit growth, may impair sporulation. For given extracellular conditions, intracellular Li+ concentrations are lower in the more tolerant yeast strains.
TL;DR: It was shown that the amylolytic enzyme system is completely extracellular, equally well induced by starch, amylose or amylopectin and that it consists mainly of enzymes of the glucoamylase type which yield glucose as the main product of starch hydrolysis.
Abstract: The mechanism of starch degradation by the fungus Trichoderma viride was studied in strain CBS 354.44, which utilizes glucose, starch and dextrins but is unable to assimilate maltose. It was shown that the amylolytic enzyme system is completely extracellular, equally well induced by starch, amylose or amylopectin and that it consists mainly of enzymes of the glucoamylase type which yield glucose as the main product of starch hydrolysis. Small amounts of alpha-amylase are produced also. The enzymes produced in starch cultures degrade starch, amylose and amylopectin equally well. Enzyme synthesis in starch media takes place to a considerable extent after exhaustion of the carbon source when maximum growth has been attained. Low-molecular dextrins are degraded by extracellular enzymes of the glucoamylase type. These enzymes are produced in media containing starch or dextrins. Maltotriose is consumed for only one third leaving maltose in the culture filtrate. Maltose is hardly attacked and hardly induces any amylolytic enzyme activity. No stable alpha-glucosidase appears to be produced.
TL;DR: The anaerobic character of P. pentosaceum may be explained by the inhibition of synthesis of both cytochrome b and enzymes in the presence of oxygen, which is explained by inavailability of NADH needed for the conversion of oxaloacetate into malate in the reductive pathway to succinate, so that succinate and propionate cannot be formed.
Abstract: When anaerobic cultures of Propionibacterium pentosaceum were shifted to low dissolved-oxygen concentration (D.O.C.), acetate production from lactate diminished and propionate production stopped, whereas pyruvate accumulated and oxygen was consumed. Assuming that energy is generated in the electron transfer to oxygen, YATP values (g dry wt bacteria/mole ATP) of between 7.2 and 11.9 were calculated from molar growth yields and product formation. When oxidative phosphorylation in the electron transfer to oxygen was ignored, unreasonably high YATP values were obtained. From these results it is concluded that energy is indeed generated in the electron transfer to oxygen. However, synthesis of cytochrome b was strongly repressed by oxygen. Furthermore, synthesis of all catabolic enzymes studied was impaired in bacteria growing at low D.O.C. Thus, the anaerobic character of P. pentosaceum may be explained by the inhibition of synthesis of both cytochrome b and enzymes in the presence of oxygen. It was demonstrated that nitrate reductase is synthesized constitutively in P. pentosaceum. Synthesis of nitrate reductase was stimulated by nitrate and repressed by oxygen. Synthesis of fumarate reductase was also repressed by oxygen, whereas only a small effect of nitrate on this enzyme was observed. However, propionate formation is inhibited during growth with nitrate. The absence of propionate formation in the presence of oxygen and nitrate is explained by inavailability of NADH needed for the conversion of oxaloacetate into malate in the reductive pathway to succinate, so that succinate and propionate cannot be formed.
TL;DR: Biochemical characters do not support an assumed relationship between Ophiostoma (including Europhium), but a relationship between Cephaloascus fragrans and Ceratocystis cannot be excluded on the basis of the biochemical characters.
Abstract: Carbohydrates of intact cells and cell walls were studied by gas-liquid chromatographical analysis after acid hydrolysis. Isolated cellulose was determined by infrared spectrophotometry, pyrolysis mass spectrometry and histochemistry. Biochemical characters do not support an assumed relationship between Ophiostoma (including Europhium) and Cephaloascus fragrans. Cephaloascus fragrans differs from Ophiostoma by a high mannose content and by the absence of cellulose and rhamnose. A relationship between Cephaloascus fragrans and Ceratocystis cannot be excluded on the basis of the biochemical characters, although there is a marked difference in conidiogenesis. Saprolegnia ferax (Oomycetes) was included as a cellulose-containing fungus for comparison.
TL;DR: The imperfect species currently cited as Candida ciferrii was found to constitute the haploid mating types of an undescribed, filamentous, heterothallic ascomycete and has been transferred to the new genus Stephanoascus.
Abstract: The imperfect species currently cited as Candida ciferrii was found to constitute the haploid mating types of an undescribed, filamentous, heterothallic ascomycete. This perfect state has been transferred to the new genus Stephanoascus. The diagnosis of the genus and the description of the species Stephanoascus ciferrii are given.
TL;DR: In Candida chodatii, a mycelial yeast having denticulate conidiogenous cells, the asci are formed by conjugating budding cells (conidia) and usually contain 2 hat-shaped, small ascospores.
Abstract: In Candida chodatii, a mycelial yeast having denticulate conidiogenous cells, the asci are formed by conjugating budding cells (conidia) and usually contain 2 hat-shaped, small ascospores. It is classified in Hyphopichia, a new genus of the Ascoideaceae. A key to the genera of the Ascoideaceae is given.
TL;DR: The data indicate C. krusei and C. sorbosa to be the same species and to represent imperfect forms of P. kudriavzevii.
Abstract: Pichia kudriavzevii and P. terricola were found to be heterothallic, but not interfertile with one another; nor did they mate with P. membranaefaciens, P. scutulata, Candida lambica, C. diversa, C. ingens, C. silvae, C. valida, C. vini, C. norvegensis, or Torulopsis inconspicua. Limited conjugation occurred between mating types of P. kudriavzevii and C. krusei and conjugation and sporulation occurred in mixtures with C. sorbosa. The data indicate C. krusei and C. sorbosa to be the same species and to represent imperfect forms of P. kudriavzevii.
TL;DR: Hydrogenase activity in cells of the nitrogen-fixing methane-oxidizing bacterium strain 41 of the Methylosinus type increased markedly when growth was dependent upon the fixation of gaseous nitrogen.
Abstract: Hydrogenase activity in cells of the nitrogen-fixing methane-oxidizing bacterium strain 41 of the Methylosinus type increased markedly when growth was dependent upon the fixation of gaseous nitrogen. A direct relationship may exist between hydrogenase and nitrogenase in this bacterium. Acetylene reduction was supported by the presence of hydrogen gas.
TL;DR: Yields of Thiobacillus denitrificans on different substrates were compared and it could be calculated that during anaerobic oxidation of thiosulphate with nitrate 1.41 or 1.16 ATP per 2 electrons are generated if 1 or 2 ATP respectively per thiosULphate is formed in substrate-level phosphorylation.
Abstract: Yields of Thiobacillus denitrificans on different substrates were compared. The organism was grown in a chemostat at a dilution rate of 0.03 h-1. From the difference in the cell yields with (1) oxygen (6.40 g carbon per mole thiosulphate) and (2) nitrate (4.51 g carbon per mole thiosulphate) as an electron acceptor the experimental value for YATP was estimated to be 1.75. The efficiency of the biosynthetic system would be 42% if 1 ATP should be needed in reversed electron transport, and 57% if this was 2 ATP per electron pair.
TL;DR: Twenty-eight strains of microaerophilic, motile, slightly curved gramnegative rods isolated from the gingival crevice of patients with gingivitis were studied and seemed similar to Vibrio sputorum, though eleven strains differed in minor characters from Bergey's description under the new name Campylobacter spUTorum, subspecies Sputorum.
Abstract: Twenty-eight strains of microaerophilic, motile, slightly curved gramnegative rods isolated from the gingival crevice of patients with gingivitis were studied. They seemed similar to Vibrio sputorum, though eleven strains differed in minor characters from Bergey's description under the new name Campylobacter sputorum, subspecies sputorum. The oral strains studied appeared to be closely related to several species of the genus Campylobacter and to Vibrio succinogenes.
TL;DR: Yeasts from a carbonated orange drink, raw materials, and intermediate products originating from 6 Iraqi bottling plants were examined and results are discussed and compared to those obtained in European soft drinks.
Abstract: Samples of a carbonated orange drink, raw materials, and intermediate products originating from 6 Iraqi bottling plants were examined 69 drinks, 4 flavoured syrups and 19 simple syrups contained yeasts, whereas all samples from one plant and all samples of beverage base were free from viable yeasts From the orange drink 2 species were isolated viz Saccharomyces montanus and Torulopsis stellata The following species were present in simple syrup: Hansenula anomala, Sacch bisporus var mellis, T candida and T stellata Sacch bisporus var mellis was also isolated from flavoured syrup Representative strains were submitted to routine growth tests at reduced oxygen tension, at reduced water activity and on solid soft-drink media containing various amounts of anti-microbially active benzoic acid at pH 30 The results are discussed and compared to those obtained in European soft drinks
TL;DR: Several pure cultures of methane-utilizing bacteria, including types I and II membrane representatives, were found to be capable of fixing nitrogen, apparently common in methane-oxidizing bacteria.
Abstract: Several pure cultures of methane-utilizing bacteria, including types I and II membrane representatives, were found to be capable of fixing nitrogen. One nitrogen-fixing isolate grew in liquid medium, but not on a solid agar medium. Apparently, the ability to fix nitrogen is common in methane-oxidizing bacteria.
TL;DR: Chemical changes occurring in the defined medium revealed that glucose was efficiently utilized after 96 hours incubation whereas total soluble nitrogen levels increased following an initial sharp decrease.
Abstract: A chemically defined medium was developed for the biosynthesis of cephalosporin C by Paecilomyces persicinus Nicot strain P-10. Glucose served as the major carbon source and nitrogen was supplied by five amino acids, l-arginine, l-aspartic acid, l-glutamic acid, glycine and dl-methionine. Omission of any of the first four diminished or prevented production of cephalosporin C; omission of methionine did not. Methionine is not critical for the production of cephalosporin C in this defined medium. Production of the antibiotic was affected by the concentrations of inorganic salts employed. Biotin was required for growth and cephalosporin C synthesis. The addition of l-lysine precursors to the medium did not influence cephalosporin C levels and l-lysine itself inhibited antibiotic production. Known precursors of β-lactam antibiotics as well as oleic acid did not affect biosynthesis of cephalosporin C. Chemical changes occurring in the defined medium revealed that glucose was efficiently utilized after 96 hours incubation whereas total soluble nitrogen levels increased following an initial sharp decrease. Mycelial weight and cephalosporin C production were both maximal after 96 hours incubation. Mycelial nitrogen was highest after 48 hours incubation whereas mycelial lipid levels were greatest after 72 hours.
TL;DR: Results of a viability test on 17–18 years old lyophilized cultures are reported and the results are reported to be in line with previous results.
Abstract: Results of a viability test on 17–18 years old lyophilized cultures are reported.
TL;DR: The careful regulation of the synthesis of the dextrinizing enzyme is discussed with special reference to the production of non-utilizable maltose by the Trichoderma viride strain CBS 354, which requires the presence of starch or dextrins.
Abstract: The synthesis of amylolytic enzymes by the maltose not-utilizing Trichoderma viride strain CBS 354.44 requires the presence of starch or dextrins. Several readily utilizable carbon sources such as glucose and glutamic acid were shown to exert a strong catabolite repression which completely inhibited enzyme induction by starch or dextrins.
TL;DR: The effect of chloral hydrate, an inhibitor of methanogenesis, on the participation of the acrylate pathway in the formation of propionate from lactate in rumen contents of cattle was studied in vitro, finding that the flux of carbon through both the acRYlate and the dicarboxylic acid pathway is increased during chloral Hydrate feeding.
Abstract: The effect of chloral hydrate, an inhibitor of methanogenesis, on the participation of the acrylate pathway in the formation of propionate from lactate in rumen contents of cattle was studied in vitro. Addition of chloral hydrate resulted in only a small stimulation of the acrylate pathway, much lower than the stimulation of propionate production by chloral hydrate. This means that the flux of carbon through both the acrylate and the dicarboxylic acid pathway is increased during chloral hydrate feeding. The influence of time of sampling after feeding on the contribution of the acrylate pathway was studied in a separate experiment. A marked drop in the participation of the acrylate pathway in propionate formation from lactate during at least 2 h after feeding was observed, whereafter a rapid rise to prefeeding levels occurred.