Showing papers in "Journal of General and Applied Microbiology in 1991"
TL;DR: It is suggested that S 97 might evolve substances already during seed germination that are translocated to the foliage; there they might accumulate around the site of bacterial multiplication and contribute to their restricted growth.
Abstract: With the aim of elucidating the immunizing ability of plant-growth-affecting rhizosphere pseudomonads, seeds of a susceptible bean (Phaseolus vulgaris L) cv. Bonita, were subjected to bacterization before challenging with the halo blight bacterial pathogen Pseudomonas syringae pv. phaseolicola. In the greenhouse, induced systemic resistance to halo blight was found in bean plants treated with a plant growth stimulatory strain of P. fluorescens (S 97), whereas deleterious pseudomonads MA 250 and VS 50 were found to induce susceptibility towards the disease. Immunization ability of S 97 was reduced at low inoculum densities (<107 live cells per ml) or eliminated when the suspension was autoclaved. The maximum disease protection, measured in terms of number of halo blight lesions in trifoliate leaves, was obtained at the highest inoculum concentration (108 live cells per ml). Agar diffusion assay in vitro revealed that S 97 exhibits bacteriostatic activity against the bean pathogen. It is suggested that S 97 might evolve substances already during seed germination that are translocated to the foliage; there they might accumulate around the site of bacterial multiplication and contribute to their restricted growth.
196 citations
TL;DR: The enzymatic hydrolysis of native and pretreated chitin by the culture filtrate of Myrothecium verrucaria NCIM 903 indicated that the swelling of the ordered structure results in efficient hydrolyzing.
Abstract: The enzymatic hydrolysis of native and pretreated chitin by the culture filtrate of Myrothecium verrucaria NCIM 903 was studied. Also, factors which influence the enzymatic hydrolysis such as pH, temperature, enzyme and substrate concentration and enzyme adsorption characteristics (n-value) were studied. Chitin hydrolysate was also used as a substrate for Single Cell Protein (SCP) production using Saccharomyces cerevisiae NCIM 3052. With M. verrucaria chitinase complex, native and acid swollen chitin were hydrolyzed at pH 5.0 and 40°C, 12.7% and 39.6% respectively. The n values which is a measure of adsorption characteristics of an enzyme were 0.4 and 0.63 for native and acid swollen chitin, respectively. This indicates that the swelling of the ordered structure results in efficient hydrolysis. As the end-product of hydrolysis of chitin was mainly N-acetyl-D-glucosamine, its further utilization as a substrate for SCP production was investigated. A biomass of 9.5g/l with a growth yield of 0.27g/g of substrate utilized was obtained. The total protein and nucleic acid content of the biomass was 61% and 3.1%, respectively.
75 citations
TL;DR: This analytical system provided quantitative information about the population shift in the indigenous bacterial flora of sludge as affected by physico-chemical or biological stress and could be enhanced by numerical analysis of the profiles using the `overlap' coefficient and mean linkage algorithm.
Abstract: AKIRA HIRAISHI,* YOSHIAKI MORISHIMA, AND JUN-ICHI TAKEUCHII Tokyo Research Laboratory, Konishi Co., Ltd., Sumida-ku, Tokyo 130, Japan 1 Shingashi Treatment Plant, Bureau of Sewage-Works, Tokyo Metropolitan Government, Itabashi-ku, Tokyo 175, Japan (Received September 21, 1990)The quinone composition of 10 sludge samples consisting of plant-derived activated sludges, laboratory activated sludges, and photosynthetic sludges was analyzed by high-performance liquid chromatography, thin-layer chromatography, and mass spectrometry. The quinone profiles of these sludges showed taxonomic divergence among the sludge bacterial communities. The information could be enhanced by numerical analysis of the profiles using the `overlap' coefficient and mean linkage algorithm. This analytical system provided quantitative information about the population shift in the indigenous bacterial flora of sludge as affected by physico-chemical or biological stress. The quinone profile method with numerical analysis is quite useful for investigating the bacterial community dynamics over time and space, without the necessity of culturing.
69 citations
TL;DR: Nine castrated Japanese Saanen goats were used to investigate the effects of saturated fatty acids and their derivatives on the rumen ciliate protozoa and Lauric acid and its derivatives might be used to establish Epidinium mono-faunated animals.
Abstract: Nine castrated Japanese Saanen goats were used to investigate the effects of saturated fatty acids and their derivatives on the rumen ciliate protozoa. The goats were first fed a test diet composed of 500g of basal diet and 25g of one of the following: caprylic acid (C8), capric acid (C10), lauric acid (C12), myristic acid (C14), palmitic acid (C16) or stearic acid (C18). C10 proved to be the most toxic for the protozoa. Progressively less inhibition was displayed with either an increase or a decrease in the carbon chain length. Second, calcium (Ca) salts and triglycerides (TG) of C8 and C10 were applied. With the feeding of C10Ca or C10TG, the protozoa in the rumen disappeared. The toxic effects of free fatty acids were not alleviated by the derivatives. Third, protozoa other than Epidinium in a mixed-faunated goat disappeared after the feeding of hydrated coconut oil (52% lauric acid). Capric acid and its derivatives are considered useful rumen-defaunating agents. Lauric acid and its derivatives might be used to establish Epidinium mono-faunated animals.
64 citations
TL;DR: Results suggest that acetate serves as an electron sink in M. elsdenii, where the growth rate was kept relatively low by limiting the glucose supply, and adding acetate similarly increased butyrate production.
Abstract: In batch culture, addition of acetate stimulated the initial growth of Megasphaera elsdenii in medium containing glucose and Trypticase. As the initial concentration of acetate was increased, butyrate production increased. When acetate was used, the rate of butyrate production increased. Hydrogen production was decreased by adding acetate. Inhibition of hydrogen production by the hydrogenase inhibitor carbon monoxide inhibited the growth of M. elsdenii, but this inhibition was cancelled by adding acetate. In continuous culture, where the growth rate was kept relatively low by limiting the glucose supply, adding acetate similarly increased butyrate production. These results suggest that acetate serves as an electron sink in M. elsdenii.
50 citations
37 citations
TL;DR: Minimum water activities for the growth of 35 yeast strains isolated from high-sugar foods and related materials were determined by incubating in broths containing 1% glucose, 0.5% polypeptone, and about half of the species showed the lowest minimum aw for growth in sucrose-media.
Abstract: Minimum water activities (aw) for the growth of 35 yeast strains isolated from high-sugar foods and related materials were determined by incubating in broths containing 1% glucose, 0.5% polypeptone, 0.3% yeast ext., 0.3% malt ext. and aw-controlling solutes at 25°C for up to 120 days. Three kinds of sugars (glucose, fructose, sucrose) and sodium chloride were used as aw-controlling solutes. The minimum aw for growth of the yeasts depended on aw-controlling solutes as well as yeast species and strains. Most species showed the highest minimum aw for growth in NaCl-media and about half of the species showed the lowest minimum aw for growth in sucrose-media. One strain of Zygosaccharomyces rouxii had minimum aw for growth as low as 0.67 in fructose-media. Miso ext. and koji ext., rich in inositol, and casamino acid decreased minimum aw for growth of Z. rouxii in NaCl-media. Pre-incubation in the presence of high concentrations of glucose or fructose also decreased minimum aw for growth of yeasts in glucose-media or fructose-media.
34 citations
TL;DR: A new genus Kockovaella Nakase, Banno et Yamada in the Hyphomycetes is described for yeasts that reproduce by non-ballistosporous stalked conidia, ballistospores and budding yeast cells.
Abstract: A new genus Kockovaella Nakase, Banno et Yamada in the Hyphomycetes is described for yeasts that reproduce by non-ballistosporous stalked conidia, ballistospores and budding yeast cells. Strains in this genus have Q-10 as the major isoprenologue of ubiquinones, contain xylose in the cells, and are positive to diazonium blue B reaction. Two new species, Kockovaella thailandica (type species) and K. imperatae, are described in the genus. Kockovaella thailandica has a G+C content of DNA of 49.5 mol% (from Tm) or 47.7-48.4mol% (by HPLC) and forms asymmetrical kidney-shaped or ellipsoidal ballistospores, whereas K. imperatae has a G+C content of DNA of 52.3mol% (from Tm) or 49.0mol% (by HPLC) and forms symmetrical globose to napiform ballistospores. Electrophoretic comparison of eight enzymes and DNA similarity indicated that K. thailandica and K. imperatae are distinct species from each other. The partial sequencing study on 18S ribosomal RNA suggested a close relationship among species of Kockovaella, Fellomyces and Sterigmatosporidium. The latter two genera resemble Kockovaella in the production of non-ballistosporous stalked conidia and the presence of xylose in the cells but produce neither ballistospores nor budding yeast cells.
34 citations
TL;DR: Results indicate that HMP contributes much more in lysine fermentation, probably because of the greater requirement of NADPH in l Lysine formation from glucose.
Abstract: Glucose metabolism in Corynebacterium glutamicum was investigated using 13C nuclear magnetic resonance (13C NMR) spectroscopy. L-Glutamic acid and L-lysine producers were cultivated in medium containing [1-13C]- or [6-13C] glucose, and the 13C NMR spectrum of the culture filtrate was measured. In each fermentation, the ratio of the contributions of the Embden-Meyerhof pathway (EMP) and the hexosemonophosphate pathway (HMP) (EMP/HMP) was calculated on the basis of the 13C population at each carbon in the products. The EMP/HMP was estimated as 80/20 in glutamic acid fermentation; in contrast, it was 30-40/60-70 in lysine fermentation. These results indicate that HMP contributes much more in lysine fermentation, probably because of the greater requirement of NADPH in lysine formation from glucose.
27 citations
TL;DR: The fractionation of bioflocculant FIX produced by Nocardia amarae YK1 revealed that the floccculant was a mixture of more than three substances, and infrared spectrophotometry suggested that the chief components of fractions might be peptides.
Abstract: The fractionation of bioflocculant FIX produced by Nocardia amarae YK1 revealed that the flocculant was a mixture of more than three substances. Although individual fractions did not exhibit the ability of flocculation at pH 5 to 7, synergetic flocculation was observed at pH 7 after mixing the fractions. Infrared spectrophotometry suggested that the chief components of fractions might be peptides. Enzymatic digestion of peptide moiety resulted in disappearance of flocculation activity. One of the ingredients of FIX carried high contents of glycine (25.6%), alanine (13.8%), and serine (12.3%), of which R groups were relatively small.
27 citations
TL;DR: It was found that oxidation of phenol in the cells of Rhodotorula rubra was partially inhibited by bipyridyl and that a catechol branch in β-ketoadipate pathway exists in the yeast strains.
Abstract: The effect of phenol on the growth and oxygen uptake rate was studied in several strains in the genus Rhodotorula, and the degradation route of phenol by two yeast strains of Rhodotorula rubra was examined.Rhodotorula rubra IFO 0870, 0889, 0892, 1100 and 1101 grew well in medium containing 250mg/l phenol. Rhodotorula rubra IFO 0870 still showed a small growth even in medium containing 1, 000mg/l phenol. It was found that oxidation of phenol in the cells of Rhodotorula rubra was partially inhibited by bipyridyl.Phenol metabolites were separated and identified using high performance liquid chromatography (HPLC) and gas chromatography/mass spectrometry (GC/MS). The two phenol metabolites were identified as catechol and cis, cis-muconic acid. These findings suggest that phenol is hydroxylated prior to ring-cleavage and that a catechol branch in β-ketoadipate pathway exists in the yeast strains. Catechol may be oxidized by the "ortho type" of ring fission.
TL;DR: Two strains, Fe1 and Fe2, of iron-oxidizing bacteria from acid drainage water at the Matsuo mine showed dissimilar characteristics of red-brown colonies on FeSO4-9K silica gel plates, however, these bacteria, identified as Thiobacillus ferrooxidans, were different strains.
Abstract: Two strains, Fe1 and Fe2, of iron-oxidizing bacteria from acid drainage water at the Matsuo mine showed dissimilar characteristics of red-brown colonies on FeSO4-9K silica gel plates. The Fe1 colonies were large and irregular. The Fe2 colonies were minute and circular. These bacteria, identified as Thiobacillus ferrooxidans on the basis of their physiological and chemotaxonomical properties (fatty acid composition, ubiquinone type, and DNA base composition), were different strains. Fe2 differed from Fe1 in its extremely low oxidizing activity of sulfur and thiosulfate. Two strains, S2 and S3, of sulfur-oxidizing bacteria were separately isolated on Na2S2O3-9K silica gel plates and agar plates, respectively. However, S2 and S3 formed pale brown and pale yellow colonies on the silica gel and agar plates, respectively. Since these two strains were identical in their properties, they were judged to be quite similar or the same strain. From their morphological, physiological, and chemotaxonomical properties, they were identified as Thiobacillus thiooxidans. The oxidation characteristics of both sulfur and thiosulfate by the strains of iron- and sulfur-oxidizing bacteria were also investigated.
TL;DR: Fab fragments of anti-32 kDa or anti-45 kDa subunits antibodies effectively inhibited adhesion of the organism to HeLa cells, suggesting that the S layer had a direct role in adhesion.
Abstract: The S layer of Clostridium difficile GAI 0714, which was composed of squarely arrayed, two-subunit proteins with respective molecular weights of 32 kDa and 45 kDa, was examined for its morphological, physicochemical, and biological properties. Optical diffraction analysis of the S layer showed that the surface-arrayed rhombus had four sides of 8.1 nm with interior angles of 8 8 ° . The two proteins were heterogeneous to each other in respect to the first ten N-terminal amino acid sequences except for residues No's. 4 and 9. Self-assembly of the subunit proteins into a regular array was dependent on such divalent cations as Ca2t or Zn2+, but not Ba2+ or Mg2t . When the mixture, made of purified 32 and 45 kDa subunits in an equal concentration ratio on a protein basis was submitted to self assembly, flattened paracrystalline sheetlike fragments were generated. However, neither sheetlike fragments nor regular arrays was observed for any self-assembled products derived from each subunit alone or their quantitatively heterologous mixtures. Intact cells of the organism adhered significantly to HeLa cells or mouse fibroblast 929 cells, whereas 8 M ureaor 4 M guanidinehydrochloride-extracted bacteria, from which both S layer protein subunits were removed, scarcely adhered to both cells. Fab fragments of anti-32 kDa or anti-45 kDa subunits antibodies effectively inhibited adhesion of the organism to HeLa cells, suggesting that the S layer had a direct role in adhesion.
TL;DR: The distinguished character of "aspergillum" for Aspergillus and of "penicillus" for Penicillium appears to be a phylogenetic indicator and contrast with the diversity of teleomorphs and the heterogeneity of ubiquinone systems.
Abstract: Partial sequence comparisons of 18S ribosomal RNA comprising 558 nucleotides in the positions 384-562, 942-1119, and 1419-1623 were used to determine the evolutionary affinities among eleven species of Aspergillus and associated teleomorphs, including five species of the most diverse sect. Ornati, and two species of Penicillium with teleomorphs. The species compared were Eurotium repens, Aspergillus fumigatus, Sclerocleista ornata, Hemicarpenteles paradoxus, H. acanthosporus, Warcupiella spinulosa, A. raperi, Emericella nidulans, A: flavus, A. oryzae, Chaetosartorya cremea, Eupenicillium crustaceum, and Talaromyces flavus. Phylogenetic trees were constructed by the unweighted pair-group method using arithmetic averages (UPGMA) and the neighbor-joining (NJ) method from evolutionary distances (Knuc). The sequence differences between the eleven species of Aspergillus and associated teleomorphs were slight, indicating only recent diversification. These observations contrast with the diversity of teleomorphs and the heterogeneity of ubiquinone systems. Both UPGMA and NJ trees based on the above sequence data, and the present known data of 18S rRNA partial sequences comprising a total of 188 nucleotides in the positions 1419-1607 from Aspergillus, Penicillium and associated teleomorphs showed that the anamorphic genera Aspergillus and Penicillium are well separated from each other. The distinguished character of "aspergillum" for Aspergillus and of "penicillus" for Penicillium appears to be a phylogenetic indicator.
Journal Article•
TL;DR: The use of a membrane inlet triple quadrupole mass spectrometer revealed indole as an end product in the growth medium of cultures of the cattle parasite Tritrichomonas foetus and the human parasite Trichomonas vaginalis: formation of indole is enhanced in the presence of added tryptophan.
Abstract: The use of a membrane inlet triple quadrupole mass spectrometer revealed indole as an end product in the growth medium of cultures of the cattle parasite Tritrichomonas foetus and the human parasite Trichomonas vaginalis: formation of indole is enhanced in the presence of added tryptophan. Two different clinical isolates of Trich. vaginalis also produce dimethyl disulphide. Electron impact ionization yielded complex fragmentation mixtures, but the facility for analysis of daughter ions enabled unequivocal assignments. Chemical ionization gave [M + 1]+ species, and tandem mass spectrometry produced identification through daughter ions. The method provides a rapid single-step procedure for the characterization of microbial products without the need for preliminary separation and derivatization.
TL;DR: Four hundred and sixteen strains of aerobic, endospore-forming bacteria belonging to the genus Bacillus were physiologically characterized using a total of 329 miniaturized tests using the UPGMA algorithm and the SSM and the SJ coefficients as measures of similarity to confirm the results of previously published data.
Abstract: Four hundred and sixteen strains of aerobic, endospore-forming bacteria belonging to the genus Bacillus were physiologically characterized using a total of 329 miniaturized tests. Overall similarities of all strains for 295 unit characters were determined by numerical taxonomic techniques using the UPGMA algorithm and the SSM and the SJ coefficients as measures of similarity. The test error and cophenetic correlation were within acceptable limits. Comparison of photometric and visual test reading revealed overall differences of 12.3%. A total of 30 clusters (2 or more strains) and 20 single member clusters were defined at the 86.7 to 89.4% levels (SSM). Generally similar groupings were obtained with the Jaccard coefficient with some changes in the definition of clusters. Heterogeneity was found within the species Bacillus brevis, B. circulans, B. macerans, B. coagulans, B. megaterium, B. sphaericus and B. stearothermophilus, thus confirming the results of previously published data. For the clusters and for some subclusters containing two or more strains the minimum number of differentiating characters was selected by computer programs (CHARSEP, DIACHAR, MOSTTYP) and a frequency matrix for probabilistic identification was constructed consisting of 40 tests versus 36 clusters and subclusters. This matrix was theoretically evaluated using a computer program (MATIDEN), and out of 391 strains, a total of 287 (73.40%) were correctly identified with a Willcox probability p>0.99. Another 34 strains (8.69%) achieved Willcox probabilities above 0.90, for 19 strains (4.85%) p exceeded 0.8, and 27 strains (6.90%) achieved Willcox probabilities>0.5. For 24 strains (6.13%) no correct identification result was obtained.
TL;DR: A metabolic sequence for phenol degradation is proposed, which suggests that phenol may be hydroxylated to form catechol prior to ring cleavage, and catechols may be further oxidized to cis, cis-muconic acid, muconolactone, β-ketoadipate enol-lactone and β- ketoadipic acid.
Abstract: The metabolic pathway of phenol was examined in the yeast strains of Rhodotorula (R) rubra IFO 0892 and 1101 Changes in concentrations of phenol, phenol metabolites and dissolved organic carbon (DOC) in a medium were determined during incubation of phenol-grown cells with a phenol solution A decrease in DOC concentration indicated that phenol was used as a carbon source The phenol metabolites were separated and identified using high performance liquid chromatography (HPLC) and gas chromatography/mass spectrometry (GC/MS) For HPLC analysis of β-ketoadipic acid, 2, 4-dinitrophenylhydrazone derivative was prepared This analysis is very selective and sensitive For GC/MS analysis, metabolites in the cultured broth were extracted with ethyl acetate and trimethylsilylated using N, o-bis(trimethylsilyl)acetoamide Formation of muconolactone and β-ketoadipate enol-lactone from phenol was studied using whole cells β-Ketoadipic acid was produced from muconolactone by the crude cell-free extract of R rubra IFO 0892 and 1101 From the results in this study, a metabolic sequence for phenol degradation is proposed Phenol may be hydroxylated to form catechol prior to ring cleavage, and catechol may be further oxidized to cis, cis-muconic acid, muconolactone, β-ketoadipate enol-lactone and β-ketoadipic acid The catechol branch in the, β-ketoadipate pathway may exist in R rubra and this catechol may be oxidized by the ortho type of ring fission
TL;DR: The partial base sequences of 18S and 26S rRNAs were examined in eighteen strains of Debaryomyces, Torulaspora, and Yamadazyma species including two strains of D. udenii.
Abstract: The partial base sequences of 18S and 26S rRNAs were examined in eighteen strains of Debaryomyces, Torulaspora, and Yamadazyma species including two strains of D. udenii. All of the strains of Debaryomyces species constituted a single group (cluster) phylogenetically. In the partial base sequence (positions 493 through 622, 130 bases) of 26S rRNA, the maximum homologies were 79-99% among Debaryomyces species. T. globosa and Y. philogaea had 71-78% and 81-87% maximum homologies, respectively, with Debaryomyces species. In the partial base sequence (positions 1611 through 1835, 225 bases) of 26S rRNA, the base differences numbered 5-0 among Debaryomyces species. T. globosa and Y. philogaea had 15-13 and 10-8 base differences, respectively, with Debaryomyces species. In the partial base sequence (positions 1451 through 1618, 168 bases) of 18S rRNA, Debaryomyces species were divided into two subgroups (subclusters). The first subgroup was comprised of D. hansenii, D. melissophilus, D. udenii, and so on, and the second subgroup comprised of D. castellii, D. polymorphus, D. yamadae, and so on. The base difference numbered 1 between the two subgroups. T. globosa and Y. philogaea had 5-4 and 1-0 base differences, respectively, with Debaryomyces species. Between T. globosa and S. cerevisiae, there was 1 base difference. D. tamarii occupied a distant position (maximum homologies, 63-71%; base differences, 50-48 and 20-19, respectively).
TL;DR: The intracellular Na+ content of the halotolerant bacterium Brevibacterium sp.
Abstract: Internal cation concentrations of the halotolerant bacterium Brevibacterium sp. were investigated, with the cells grown in a complex media supplemented with nine kinds of salts. With increases in the external NaCl concentration, the amount of Na+ ion in the cells increased, while the intracellular concentration of the K+ ion remained almost constant (about 300mM). The same tendency was observed when NaCl was replaced with KCl, although the Na+ ion was very low (about 15mM). On the contrary, intracellular concentrations of Mg2+ and Ca2+ decreased slightly with the increase in NaCl or KCl concentrations in the medium. When the RbCl concentration in the medium was increased to more than 100mM, Rb+ ions in the cells increased about one hundred times, 550-600 mM, while K+ ions decreased to one-tenth. The same experiment was resumed using the chemically defined medium. We observed two different phenomena. First, the intracellular Na+ content (about 200mM) was more than ten-fold higher than that of the cells grown in the complex medium. Second, the release of K+ ions from the cells at alkaline pH was not as remarkable as that in the complex medium. The release of K+ ions observed in the complex medium was correlated with the addition of 50 mM diethanolamine-hydrochloride for adjusting medium pH at 9.0.
TL;DR: The aerobic fatty acid desaturase system evidently contributes to in vivo formation of at least a part of unsaturated fatty acids in this bacterium.
Abstract: 3-Decynoyl N-acetylcysteamine (DNAC), a specific inhibitor of the anaerobic pathway for bacterial unsaturated fatty acid synthesis, completely inhibited the growth of a psychrotrophic bacterium, Pseudomonas sp. strain E-3 (Pseudomonas E-3), in a succinate-salt medium. But the DNAC-inhibited growth was effectively relieved by supplementing saturated fatty acid in the medium. Although the in vitro synthesis of unsaturated fatty acid was inhibited by DNAC, it became insensitive to DNAC when fatty acid synthase was assayed in the presence of the membrane fraction containing Δ9 fatty acyl-CoA desaturase.When Pseudomonas E-3 was grown on pentadecanoate, a fatty acid unnatural to this bacterium, the cells contained penta- and heptadecenoate in the phospholipid, and the content of these odd-numbered unsaturated fatty acids amounted to 57% of the total unsaturated fatty acids. By cleavage of the penta- and heptadecenoate with periodate/ permanganate, they were identified as Δ9 15:1 and Δ9 17:1, respectively. All this indicates that the aerobic fatty acid desaturase system evidently contributes to in vivo formation of at least a part of unsaturated fatty acids in this bacterium.
TL;DR: The results suggest that these biologically active molecules are associated with the plasmodial membrane together with slime substances.
Abstract: Proteins and slime substances were extracted from the membrane fraction of the actively growing plasmodia of Physarum polycephalum, and analyzed by SDS-PAGE. A glycoprotein with a molecular weight of 120kD had a very high affinity for concanavalin A. The synthesis of this glycoprotein was greatly inhibited by tunicamycin. When the culture entered the stationary phase, the plasmodia produced large amounts of the slime on their surface. In the shaken culture, most of the slime substances were released from the plasmodial surface together with the 120kD glycoproteins. In this growth phase, some gelatinolytic, glycosidase and hemagglutinating activities were also released into the medium. Some of these had appeared in the membrane fraction of growing plasmodia. The results suggest that these biologically active molecules are associated with the plasmodial membrane together with slime substances.
TL;DR: It appears that the cellulase should be regarded as an endo-type cellulase, although it hydrolyzes Avicel relatively easier than CM-cellulose.
Abstract: A microcrystalline cellulose (Avicel)-hydrolyzing cellulase (an endocellulase) was isolated from a preparation of Trichoderma reesei CDU-11 and purified successively by DEAE-Sepharose CL 6B and Concanavalin A-Sepharose column chromatography, and preparative electrophoresis and on Sephadex G-100 gel filtration. The cellulase preparation showed a single protein band on SDS-PAGE slab and gel disc electrophoresis. Its molecular weight was estimated to be 64, 000 by Sephadex G-100 gel filtration and 67, 000 by SDS slab electrophoresis. The isoelectric point was at pH 4.75 on polyacrylamide gel electric focusing. This cellulase hydrolyzed more specifically water insoluble microcrystalline cellulose such as Avicel rather than water soluble cellulose such as carboxymethyl-cellulose. It produced glucose, cellobiose and cellotriose from cellotetraose and cellohexaose, and it produced a significant amount of glucose and cellobiose from Avicel. Based on these results, it appears that the cellulase should be regarded as an endo-type cellulase, although it hydrolyzes Avicel relatively easier than CM-cellulose. We obtained no evidence that this cellulase is an exo-type one named cellobiohydrolase (CBH) in the systematic nomenclature.
TL;DR: The determinations of the partial base sequences of 18S and 26S rRNAs have demonstrated that the genus Holleya is phylogenetically separable from the genera Nematospora and Metschnikowia, although the full base sequences were similar.
Abstract: The partial base sequences of 18S and 26S rRNAs of six strains of species in the genera Holleya, Nematospora, and Metschnikowia (Spermophthoraceae) were determined. The determinations of the partial base sequences (positions 1451 through 1618, 168 bases) of 18S rRNA have demonstrated that the genus Holleya is phylogenetically separable from the genera Nematospora and Metschnikowia, although the partial base sequences (positions 493 through 625, 133 bases; positions 1685 through 1835, 151 bases) of 26S rRNA in the genera Holleya and Nematospora were similar. Some discussions are presented from the taxonomic and phylogenetic points of view.
TL;DR: Megasphaera elsdenii was able to grow when the entracellular pH was as low as, 5.5, and maintained a near-neutral intracellular pH (pH;) in the wide range of pHe, and its membrane potential and Yg,uCOSe were decreased as the pHe was lowered.
Abstract: Megasphaera elsdenii was able to grow when the entracellular pH (pHe) was as low as, 5.5, and maintained a near-neutral intracellular pH (pH;) in the wide range of pHe. The membrane potential (d ~) and Yg,uCOSe were decreased as the pHe was lowered from 6.7 to 5.5. When 111 elsdenii was grown in the presence of 10 mgll monensin, 39o ethanol, or 25 mM acetate, both Yg,ucose and pH; were decreased as the pHe declined. Acetate alleviated the growth inhibition by ethanol at low pH. Unexpectedly, d g5 was increased remarkably by monensin or acetate only at pHe 6.0; this is inexplicable at present. Ethanol decreased the d c as the pHe was decreased.
TL;DR: The mode of submerged spore formation in Kitasatosporia setae was studied with pulse-labeling and radioautography, which showed that K. setae differs from Streptomyces griseus in the way SSs are formed.
Abstract: The mode of submerged spore (SS) formation in Kitasatosporia setae was studied. A time course study of SS formation with pulse-labeling and radioautography demonstrated that at the tips of the hyphal branches, premature spore chains were produced and grew into short spore chains. Then the short spore chains were fragmented to yield SS. This was supported by the morphological changes observed by Nomarski differential interference microscopy, which showed that K. setae differs from Streptomyces griseus in the way SSs are formed.