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Six mutants of Rhizobium leguminosarum 3855 lacking uptake hydrogenase activity (Hup phenotype) as a result of Tn5-mob mutagenesis of the hup-containing plasmid pRL6JI were tested for symbiotic performance on Pisum sativum L. and Vicia benghalensis L. Three pea cultivars and one vetch line, which induce four different ...
The inducible water-soluble bioemulsifier liposan (M. C. Cirigliano and G. M. Carman, Appl. Environ. Microbiol. 48:747-750, 1984) was purified from the yeast Candida lipolytica. The purification procedure included repeated solvent extractions of a concentrated culture filtrate and Affi-Gel concanavalin A affinity chrom...
Although the commercially important mushroom Lentinus (= Lentinula) edodes (Berk.) Sing. can be rapidly cultivated on supplemented wood particles, fruiting is not reliable. This study addressed the problem by developing more information about growth and development on a practical oakwood-oatmeal medium. The study deter...
Using a modification of the basic two-dimensional polyacrylamide gel electrophoresis technique, the polypeptides of the protein map of Saccharomyces cerevisiae involved in glycolysis were investigated. This study resulted in a reassignment of two of the seven glycolytic enzyme polypeptides previously identified (Ludwig...
Butyrate is an important intermediate in the anaerobic degradation of organic matter. In sulfate-depleted environments butyrate is oxidized to acetate and hydrogen by obligate proton reducers, in syntrophic association with hydrogen-consuming methanogens. This paper describes two enrichments of endospore-forming bacter...
Research on the extracellular hemeprotein ligninases of Phanerochaete chrysosporium has been hampered by the necessity to produce them in stationary culture. This investigation examined the effects of detergents on development of ligninase activity in agitated submerged cultures. Results show that addition of Tween 80,...
Various physical and chemical parameters were monitored to evaluate their influence on the microbial communities present in composting municipal sewage sludge. Temperature, moisture content, depth, pH, protein content, total nitrogen, total carbon, lipid phosphate biomass, and the rates of microbial incorporation of su...
A novel, semicontinuous solid-phase fermentation system was used to produce fuel ethanol from sweet sorghum. The process was at an intermediate scale. In the process, dried and shredded sweet sorghum was rehydrated to 70% moisture, acidified to pH 2.0 to 3.0, and either pasteurized (12 h at 70 to 80 degrees C) or not p...
Avicelase, carboxymethyl cellulase (CMCase), and beta-glucosidase activities have been compared between Clostridium thermocellum and three extremely thermophilic, cellulolytic anaerobes, isolates TP8, TP11, and KT8. The three isolates were all small, gram-negative staining, oval-ended rods which occurred singly and, at...
Three independent techniques, [H]thymidine incorporation, the reduction rate of p-iodonitrotetrazolium violet (INT) to INT formazan normalized to DNA, and the ratio of ATP to DNA, were adapted to measure the activity of attached and unattached estuarine bacteria. In experiments employing the estuarine isolate Vibrio pr...
The organization and species composition of bacterial trophic groups associated with lactose biomethanation were investigated in a whey-processing chemostat by enumeration, isolation, and general characterization studies. The bacteria were spatially organized as free-living forms and as self-immobilized forms appearing...
Diflubenzuron, an insect growth regulator that blocks chitin deposition in insect cuticles, was tested for its effects on morphogenesis of Streptomyces spp. Use of diflubenzuron resulted in reduced dominance of spore hairs, reduced the width of the outer wall, and prevented formation of the inner spore wall in S. bambe...
Aryl-O-methyl ethers are abundant in aerobic and anaerobic environments. In particular, lignin is composed of units of this type. Lignin monomers specifically radiolabeled in methoxy, side chain, and ring carbons have been synthesized by chemical procedures and are important in studies of lignin synthesis and degradati...
The O-methyl substituents of aromatic compounds constitute a C(1) growth substrate for a number of taxonomically diverse anaerobic acetogens. In this study, strain TH-001, an O-demethylating obligate anaerobe, was chosen to represent this physiological group, and the carbon flow when cells were grown on O-methyl substi...
Three strains of Caldariomyces fumago were immobilized in 4% k-carrageenan and tested for semicontinuous production of chloroperoxidase (CPO). Over an 80-day period, growing in defined medium, C. fumago strains CMI 89362 and ATCC 11925 produced enzyme concentrations of 99 and 71 mg/liter, respectively, during six produ...
A total of 286 isolates of Pseudomonas maltophilia was collected from sheep exhibiting brown or yellowish fleece rot and from fly-strike lesions. Enzyme activities for 10 of the isolates were examined by plate tests and with the API ZYM system and compared with the enzymatic profile of a human type strain of P. maltoph...
Tentoxin, a cyclic tetrapeptide produced by Alternaria alternata (Fries) Keissler, induces chlorosis in certain seedling plants. It can be extracted from culture filtrates of the fungus. Tentoxin production is stimulated and increased by using a mixture of aged culture filtrates and modified Richards solution. Aged cul...
Glycoside derivatives of 4-methylumbelliferone (MUF) were used to characterize the polysaccharidase enzyme systems present in sediments from an intertidal mud flat. The formation of highly fluorescent MUF on hydrolysis of the various glycosides was determined at low substrate concentrations (<1 muM) and with short incu...
An optimized batch fermentation process for the conversion of cattle feedlot waste filtrate, supplemented with cheese whey, into a nitrogenous feed supplement for ruminants is described. Feedlot waste filtrate supplemented with cheese whey (5 g of whey per 100 ml) was fermented by the indigenous microbial flora in the ...
In the high-rate anaerobic reactors studied (ca. 10 g of chemical oxygen demand [COD] removed per liter of reactor per day), the sulfate-reducing bacteria (SRB) were poor competitors of methane-producing bacteria (MPB), scavenging only on the order of 10 to 20% of the total electron flow. The relatively noncompetitive ...
The mode of action of the toxic fragment (P-59) derived from bipyramidal-shaped delta-endotoxin of Bacillus thuringiensis subsp. kurstaki HD-1 on the silkworm Bombyx mori was investigated. An enzyme-linked immunosorbent assay showed that there was no translocation of P-59 from the gut lumen to the hemocoel. When membra...
The effects of dissolved oxygen concentration and pH on the growth of Brevibacterium linens CNRZ 918 and its production of methanethiol from l-methionine were investigated. Optimal specific methanethiol production was obtained at 25% saturation of dissolved oxygen and at a pH between 8 and 9, whereas optimal cell growt...
Mixed cultures of Cellulomonas sp. and Azospirillum brasilense were grown with straw or cellulose as the carbon source under conditions favoring the fixation of atmospheric nitrogen. Rapid increases in cell numbers, up to 10 cells per g of substrate, were evident after 4 and 5 days of incubation at 30 degrees C for cel...
Mucor fragilis grown on bovine blood powder as the sole carbon source abundantly produced beta-N-acetylhexosaminidase. The enzyme activity was several times higher than that of a culture obtained with glucose medium. The enzyme had two different molecular weight forms. The high-molecular-weight form had somewhat higher...
Mutational experiments were performed to decrease the protease productivity of Humicola grisea var. thermoidea YH-78 using UV light and N-methyl-N'-nitro-N-nitrosoguanidine. A protease-negative mutant, no. 140, exhibited higher endoglucanase activity than the parent strain in mold bran culture at 50 degrees C for 4 day...
Two types of mesophilic, methanogenic bacteria were isolated in pure culture from anaerobic freshwater and marine mud with 2-propanol as the hydrogen donor. The freshwater strain (SK) was a Methanospirillum species, the marine, salt-requiring strain (CV), which had irregular coccoid cells, resembled Methanogenium sp. S...
Hydrogen evolution by a nitrogen-fixing cyanobacterium, Anabaena sp. strain N-7363, was tested in order to develop a water biophotolysis system under aerobic conditions. A culture of the strain supplemented with carbon dioxide under an air atmosphere evolved hydrogen and oxygen gas, which reached final concentrations o...
The effects of lactic acid bacterial fermentation on chemical and physical changes in aqueous extracts of cowpea (Vigna unguiculata), peanut (Arachis hypogea), soybean (Glycine max), and sorghum (Sorghum vulgare) were studied. The bacteria investigated were Lactobacillus helveticus, L. delbrueckii, L. casei, L. bulgari...
Several methodological variables were critical in two commonly used electron transport activity assays. The dehydrogenase assay based on triphenyl formazan production exhibited a nonlinear relationship between formazan production (dehydrogenase activity) and sediment dilution, and linear formazan production occurred fo...
The transformation of 22-hydroxy-23,24-bisnorchol-4-en-3-one to 7alpha-22-dihydroxy-23,24-bisnorchol-4-en-3-one by Botryodiploida theobromae, Lasiodiplodia theobromae, and various Botryosphaeria strains is described. Factors affecting the reaction were incubation temperature, sonication of the substrate, and addition o...
An organism capable of growth on pyridine was isolated from soil by enrichment culture techniques and identified as Micrococcus luteus. The organism oxidized pyridine for energy and released N contained in the pyridine ring as ammonium. The organism could not grow on mono- or disubstituted pyridinecarboxylic acids or h...
The impact of storm conditions on the heterotrophic activity of planktonic bacteria in a southwestern reservoir was investigated. Storm events were considered as rainfall in excess of 2.5 cm in a 24-h period before sampling. Storm conditions stimulated heterotrophic activities and resulted in increased uptake rates and...
A cellulase gene of Clostridium thermocellum was transferred to Escherichia coli by molecular cloning with bacteriophage lambda and plasmid vectors and shown to be indentical with the celA gene. The celA gene product was purified from extracts of plasmid-bearing E. coli cells by heat treatment and chromatography on DEA...
DNA isolated from streptococcal bacteriophage c6A was cut only infrequently by many restriction endonucleases. Fragments of c6A DNA cloned in Escherichia coli plasmids were similarly resistant to cleavage. We conclude that the low frequency of cleavage is due to an unusually low number of restriction enzyme recognition...
We produced a monoclonal antibody against Rhizobium trifolii 162x95. This antibody in cell culture supernatant was used in an indirect enzyme-linked immunosorbent assay to differentiate strain 162x95 from naturalized strains in the Appalachian region. Nodules crushed in 0.1 to 0.2 ml of phosphate-buffered saline and us...
Nonvolatile residue (NVR), a waste stream from the manufacture of nylon 6'6', contains mainly small carboxylic acids and alcohols, making it a potential fermentation substrate. Above a concentration of 1.3% (wt/vol), NVR inhibited the growth of all microorganisms tested. The most inhibitory of the major NVR components ...
Bacillus stearothermophilus grew better on complex and semisynthetic medium than on synthetic medium supplemented with amino acids. Amylase production on the complex medium containing beef extract or corn steep liquor was higher than on semisynthetic medium containing peptone (0.4%). The synthetic medium, however, did ...
Synthesis of granulose was investigated in 15 solvent-producing Clostridium strains. Only one of the strains did not produce granulose. The structure of granulose in Clostridium acetobutylicum P262 consisted of a high-molecular-weight polyglucan containing only (1-->4) linked d-glucopyranose units. Biosynthesis of gran...
A novel xanthan depolymerase (endo-beta-1,4-glucanase) was isolated from a salt-tolerant bacteria culture (HD1) grown on xanthan. The depolymerase was purified 55-fold through chromatography on ion-exchange and molecular sieve columns, including high-performance liquid chromatography. The purified enzyme fraction was h...
Minicells produced by Escherichia coli M2141 were used as probes to measure predation on pelagic bacteria in situ. The minicells, labeled with [S]methionine in one specific protein, were shown to disappear in the presence of a microflagellate (Ochromonas sp.), as seen by a decrease in the amount of labeled marker prote...
Previously, Bradyrhizobium japonicum USDA 110 was shown to contain colony morphology variants which differed in nitrogen-fixing ability. Mannitol-utilizing derivatives L1-110 and L2-110 have been shown to be devoid of symbiotic nitrogen fixation ability, and non-mannitol-utilizing derivatives I-110 and S-110 have been ...
We investigated the intracellular physiological conditions associated with the induction of butanol-producing enzymes in Clostridium acetobutylicum. During the acidogenic phase of growth, the internal pH decreased in parallel with the decrease in the external pH, but the internal pH did not go below 5.5 throughout batc...
Lignocellulose degradation by Streptomyces viridosporus results in the oxidative depolymerization of lignin and the production of a water-soluble lignin polymer, acid-precipitable polymeric lignin (APPL). The effects of the culture pH on lignin and cellulose metabolism and APPL production by S. viridosporus are reporte...
Ligninase activity in Phanerochaete chrysosporium is stimulated by incubating cultures with various substrates for the enzyme, including veratryl (3,4-dimethoxybenzyl) alcohol, which is a secondary metabolite of this fungus. This study was designed to provide insight into the mechanism involved in this stimulation. Lig...
Natural populations of the cyanobacteria Spirulina species and Oscillatoria species obtained from Israeli fishponds were limited in growth by nitrogen availability in summer. Physiological indicators for nitrogen limitation, such as phycocyanin, chlorophyll a, and carbohydrate content, did not show clear evidence for n...
A phenol-degrading methanogenic enrichment was successfully immobilized in agar as shown by the stoichiometric conversion of phenol to CH(4) and CO(2). The enrichment contained members of three physiological groups necessary for the syntrophic mineralization of phenol: a phenol-oxidizing bacterium, a Methanothrix-like ...
More than 90% of the aspartate in a defined medium was metabolized after lactate exhaustion such that 3 mol of aspartate and 1 mol of propionate were converted to 3 mol of succinate, 3 mol of ammonia, 1 mol of acetate, and 1 mol of CO(2). This pathway was also evident when propionate and aspartate were the substrates i...
A glutamine synthetase (GS) gene, glnA, from the gram-positive obligate anaerobe Clostridium acetobutylicum was cloned on recombinant plasmid pHZ200 and enabled Escherichia coli glnA deletion mutants to utilize (NH(4))(2)SO(4) as a sole source of nitrogen. The cloned C. acetobutylicum gene was expressed from a regulato...
Twelve white-rot fungi were grown in solid-state culture on lemon grass (Cymbopogon citratus) and citronella (Cymbopogon winterianus) bagasse. The two lignocellulosic substrates had 11% permanganate lignin and a holocellulose fraction of 58%. After 5 to 6 weeks at 20 degrees C, nine fungi produced a solid residue from ...
Methanosarcina barkeri Fusaro (DSM 804) could grow on methanol in a mineral medium containing cysteine or thiosulfate as the sole sulfur source. Optimum growth occurred at cysteine concentrations of 1 to 2.8 mM and at thiosulfate concentrations of 2.5 to 5 mM. No inhibition of growth was observed even when these concen...
p-Fluorophenylalanine-resistant mutants of starch-degrading Bacillus polymyxa ATCC 842, generated by ethyl methanesulfonate mutagenesis followed by incubation with caffeine, overproduced small amounts of l-phenylalanine (l-phe) from starch. A beta-2-thienylalanine-resistant mutant (BT-7) derived from p-fluorophenylalan...
The ability of three species of Xanthobacter to metabolize cyclohexane and its derivatives has been compared. Xanthobacter flavus was unable to utilize any of the cycloalkanes under investigation. X. autotrophicus was unable to utilize cyclohexane but was able to grow with a limited range of substituted cycloalkanes, i...
The degradability of ground hardwood by thermophilic anaerobic bacteria (Clostridium thermocellum with or without Thermoanaerobacter strain B6A) was greatly enhanced by pretreatment of the substrate with supercritical ammonia. Relative to C. thermocellum monocultures, cocultures of C. thermocellum and Thermoanaerobacte...
Among five hydrogenation catalysts, palladium on charcoal was the most reactive one when suspended in anaerobic culture medium, and Lindlar catalyst (Pd on CaCO(3)) was the most reactive one when suspended in the gas phase of culture tubes. Palladium on charcoal in the culture medium (40 to 200 mg 10 ml) completely inh...
Thirteen virulent phages and two temperate phages of two closely related bacterial species (Lactobacillus lactis and L. bulgaricus) were compared for their protein composition, their antigenic properties, their restriction endonuclease patterns, and their DNA homology. The immunoblotting studies and the DNA-DNA hybridi...
Whey, a by-product of the cheese industry, can sustain the growth of fast-growing rhizobia. To avoid any latency of growth, rhizobial inoculum must be prepared under inducing conditions. In unsupplemented whey, the number of cells of Rhizobium meliloti Balsac reached 5 x 10 CFU/ml in 48 h of incubation. This is compara...
Anaerobic San Francisco Bay salt marsh sediments rapidly metabolized [C]dimethylselenide (DMSe) to CH(4) and CO(2). Addition of selective inhibitors (2-bromoethanesulfonic acid or molybdate) to these sediments indicated that both methanogenic and sulfate-respiring bacteria could degrade DMSe to gaseous products. Howeve...
Addition of dimethylsulfide (DMS), dimethyldisulfide (DMDS), or methane thiol (MSH) to a diversity of anoxic aquatic sediments (e.g., fresh water, estuarine, alkaline/hypersaline) stimulated methane production. The yield of methane recovered from DMS was often 52 to 63%, although high concentrations of DMS (as well as ...
Rhizobium trifolii 0403 was treated with 16.6 mM succinate and other nutrients and thereby induced to grow in nitrogen-free medium. The organism grew microaerophilically on either semisolid or liquid medium, fixing atmospheric nitrogen to meet metabolic needs. Nitrogen fixation was measured via N incorporation (18% N e...
Mutational experiments were carried out to decrease the protease productivity of Aspergillus ficum IFO 4320 by using N-methyl-N'-nitro-N-nitrosoguanidine. A protease-negative mutant, M-33, exhibited higher alpha-amylaseactivity than the parent strain under submerged culture at 30 degrees C for 24 h. About 70% of the to...
Thirty-two bacterial strains growing on inulin as the sole carbon and energy source were isolated from soil samples by enrichment culture on a mineral medium. Twenty of the strains were identified as Flavobacterium multivorum. All the bacteria contained a beta-fructosidase that was active on both inulin and sucrose. Th...
Anaerobic mixed-culture aggregates, which converted glucose to acetic, propionic, butyric, and valeric acids, were formed under controlled conditions of substrate feed (carbon limitation) and hydraulic regimen. The continuous-flow system used (anaerobic gas-lift reactor) was designed to retain bacterial aggregates in a...
We evaluated three antisera and four enzyme conjugates for the detection of Bradyrhizobium japonicum by an indirect enzyme-linked immunosorbent assay in microtiter plates. Nitrocellulose membrane sheets were then evaluated as an alternative support medium by using some combinations. Partially purified immunoglobulin G ...
A Monascus pilosus strain was selected for production of intracellular alpha-galactosidase. Optimum conditions for mycelial growth and enzyme induction were determined. Galactose was one of the best enzyme inducers. The enzyme was purified by ammonium sulfate precipitation, gel filtration, and ion exchange chromatograp...
Partially purified cell wall proteinases of eight strains of Streptococcus cremoris were compared in their action on bovine alpha(s1)-, beta-, and kappa-casein, as visualized by starch gel electrophoresis, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and thin-layer chromatography. Characteristic degradati...
A thermophilic, autotrophic methanogen (strain CB12, DSM 3664) was isolated from a mesophilic biogas digestor. This bacterium used H(2)-CO(2) or formate as a substrate and grew as short rods, sometimes in pairs and in crooked filaments. Motility was not observed. Its optimum temperature (56 degrees C) was lower than th...
The purpose of this study was to determine the depth distribution of bacterial biomass and production in a stratified lake and to test techniques to measure bacterial production in anaerobic waters. Bacterial abundance and incorporation of both [H]thymidine and [H]leucine into protein were highest in the metalimnion, a...
Gaseous N losses from disturbed and reference forested watersheds at the Coweeta Hydrologic Laboratory in western North Carolina were studied by in situ N(2)O diffusion measurements and laboratory incubations throughout a 10-month period. Soil temperature, percent base saturation, and water-filled pore space accounted ...
Regenerating protoplasts were obtained from mycelial culture of the mushroom Volvariella volvacea by the action of the lytic enzyme Novozym 234 in the presence of 0.01 M phosphate buffer (pH 6.0) containing 0.6 M NaCl. Regeneration was found to be poor in liquid medium, but more than 50% regeneration was achieved on so...
Two-dimensional gel electrophoresis analysis of and total cell protein determination for three bacterial isolates from marine waters at the onset and after 24 h of energy and nutrient deprivation demonstrated that the three isolates exhibited different pathways of starvation survival. Two strains appeared to synthesize...
Substrate formulations of sawdust, wheat bran, and millet were inoculated with spawns from one hybrid and two parental genotypes of Lentinula edodes. Biological efficiency (BE) and size data on mushrooms harvested from two substrate formulations with spawn run times of 60, 90, and 120 days were analyzed. A significant ...
Phenol, p-cresol, and volatile fatty acids (VFA; acetic, propionic, isobutyric, butyric, isovaleric, and valeric acids) were used as odor indicators of swine waste. Aeration of the waste allowed the indigenous microorganisms to grow and degrade these malodorous substances. The time required for degradation of these sub...
A rapid filter paper dot-immunobinding assay was adapted to detect the wall-less mollicute Spiroplasma citri in medium, plants, or insects. Filter paper spotted with sample was incubated first in dilute antiserum, then in protein A-peroxidase, and finally in a substrate of 4-chloro-1-naphthol plus hydrogen peroxide. Th...
The sulfate kinetics in an anaerobic, sulfate-reducing biofilm were investigated with an annular biofilm reactor. Biofilm growth, sulfide production, and kinetic constants (K(m) and V(max)) for the bacterial sulfate uptake within the biofilm were determined. These parameters were used to model the biofilm kinetics, and...
Methanosarcina barkeri 227 and Methanosarcina mazei S-6 grew with acetate as the substrate; we found little effect of H(2) on the rate of aceticlastic growth in the presence of various H(2) pressures between 2 and 810 Pa. We used physical (H(2) addition or flushing the headspace to remove H(2)) and biological (H(2)-pro...
The use of Cephalosporium eichhorniae 152 (ATCC 38255) (reclassified as Acremonium alabamense; see Addendum in Proof), a thermophilic, acidophilic, amylolytic fungus, for the conversion of potato processing wastes into microbial protein for use as animal feed was studied. The fungus was not inhibited by alpha-solanine ...
Acetivibrio cellulolyticus cellulase obtained by the water elution of residual cellulose from the growth medium was compared with the cellulase activity present in culture supernatants. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis indicated that water elution released most of the protein bands whi...
The effects of ethanol and phenylethanol on the growth of and glycoprotein secretion by Trichoderma reesei were studied. Low levels (1.5%, vol/vol) of ethanol perturbed the glycosylation process, as shown by alterations in the isoelectric profile of the secreted proteins and a reduction in the rate of incorporation of ...
A general screening survey for expression of extracellular acid proteinase production was performed on over 100 cultures belonging to the genus Saccharomyces. Although two strains of Saccharomyces cerevisiae showed positive extracellular proteinase phenotypes in plate tests, it was not possible to demonstrate proteolyt...
A membrane-bound l-alpha-glutamyl (aspartyl)-peptide hydrolase (aminopeptidase A) (EC 3.4.11.7) from Streptococcus cremoris HP has been purified to homogeneity. The free gamma-carboxyl group rather than the amino group of the N-terminal l-alpha-glutamyl (aspartyl) residue appeared to be essential for catalysis. No endo...
A beta-d-xylosidase from C. acetobutylicum ATCC 824 was purified by column chromatography on CM-Sepharose, hydroxylapatite, Phenyl Sepharose, and Sephadex G-200. The enzyme had an apparent molecular weight of 224,000 as estimated by gel filtration. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed that t...
Starting with a strain of Bacillus cereus excreting about 40-fold more beta-amylase than does the original wild-type strain, we isolated, after mutagenesis with N-methyl-N'-nitro-N-nitrosoguanidine, a strain designated BQ10-S1 SpoIII which showed under optimal conditions a further 5.5-fold increase in beta-amylase acti...
Clostridium formicoaceticum homofermentatively converted lactate to acetate at mesophilic temperatures (30 to 42 degrees C) and at pHs between 6.6 and 9.6. The production of acetate was found to be growth associated. Approximately 0.96 g of acetic acid and 0.066 g of cells were formed from each gram of lactic acid cons...
Two components of the proteolytic system, proteins A and B (J. Hugenholtz, F. Exterkate, and W. N. Konings, Appl. Environ. Microbiol. 48:1105-1110, 1984), have been studied in Streptococcus cremoris Wg2 by immunological methods. The components could not be separated by standard chromatography techniques because both pr...
An enzyme which released the cellobiose group from p-nitrophenyl cellobioside was isolated from the periplasmic space of Bacteroides succinogenes grown on Avicel crystalline cellulose in a continuous cultivation system and separated from endoglucanases by column chromatography. The molecular weight of the enzyme was ap...
Changes in lactose concentration and feed rate altered bacterial growth and population levels in a whey-processing chemostat. The bacterial population and methane production levels increased in relation to increased lactose concentrations comparable to those in raw whey (6%) and converted over 96% of the substrate to m...
Percoll gradient centrifugation effectively separated Syntrophomonas wolfei cells from Methanospirillum hungatii cells, resulting in a 70- to 80-fold enrichment of S. wolfei cells relative to M. hungatii cells. The separated S. wolfei cells were viable. Gram quantities of cellular protein which was enzymatically active...
To purify pectate lyase produced by Erwinia carotovora subsp. carotovora, we used the supernatant from 48-h-old cultures grown in broth containing sodium polypectate and yeast extract. The supernatant was combined with the enzyme substrates sodium polypectate and polygalacturonic acid, which were then precipitated with...
Nine bacterial strains growing on inulin as the sole carbon and energy source were isolated from soil samples by enrichment culture on a mineral medium. Four of the strains were thermophilic and belong to the genus Bacillus. The thermophilic strains synthesized a beta-fructosidase that was active on both inulin and suc...
To develop a biochemical genetic approach to understanding cell carbon synthesis or metabolic pathways in methanogens, Methanobacterium ivanovii was selected as a model organism for genetic manipulation studies. The organism displayed a colony size of 3 to 6 mm in less than 2 weeks and had a plating efficiency of about...
Bacteriophages uc1001 and uc1002, which are lytic for Streptococcus cremoris UC501 and UC502, respectively, were characterized in detail. Comparisons were made with a previously characterized phage, P008, which is lytic for Streptococcus lactis subsp. diacetylactis F7/2, and uc3001, which is a lytic phage for S. cremor...
A cellulase gene from Thermomonospora fusca coding for endocellulase E(5) was introduced into Streptomyces lividans by using shuttle plasmids that can replicate in either S. lividans or Escherichia coli. Plasmid DNA isolated from E. coli was used to transform S. lividans, selecting for thiostrepton resistance. The tran...
Activities detectable in Streptococcus cremoris with the chymotrypsin substrate N-glutaryl-l-phenylalanine-4-nitroanilide and formerly designated endopeptidases P37 and P50 (F. A. Exterkate, Appl. Environ. Microbiol. 47:177-183, 1984) are both coupled peptidase reactions. These coupled reactions involve a membrane-boun...
A chromosomal fragment of 6.7 megadaltons (MDa), apparently containing the genes for milk protein utilization by Streptococcus lactis subsp. lactis SSL135, was cloned in S. lactis subsp. lactis MG1614, a proteinase-negative strain. For the cloning, the chromosomal DNA of SSL135 was cleaved with restriction enzyme BamHI...
Forty Frankia strains belonging to the Alnus and Elaeagnus host specificity groups and isolated from various plant species from different geographical areas were characterized by the electrophoretic separation of isozymes of eight enzymes. All the enzyme systems that were investigated showed large variation. Diaphorase...
The production of alpha-amylase, pullulanase, and alpha-glucosidase and the formation of fermentation products by the newly isolated thermophilic Clostridium sp. strain EM1 were investigated in continuous culture with a defined medium and an incubation temperature of 60 degrees C. Enzyme production and excretion were g...
During the growing season of 1984, the rhizobacteria (including organisms from the rhizosphere soil, the rhizoplane, and internal root zones) of 47 maize plants (two varieties) sampled from different locations in France and at different growth stages were inventoried. Isolates were characterized by sodium dodecyl sulfa...
High-pressure, high-temperature investigations on thermophilic microorganisms that grow on hydrogen or other gaseous substrates require instrumentation which provides sufficient substrate for cell proliferation up to 2 x 10 to 3 x 10 cells per ml under isothermal and isobaric conditions. To minimize H(2) leakage and to...
During lactate fermentation by Propionibacterium freudenreichii subsp. shermanii ATCC 9614, the only amino acid metabolized was aspartate. After lactate exhaustion, alanine was one of the two amino acids to be metabolized. For every 3 mol of alanine metabolized, 2 mol of propionate, 1 mol each of acetate and CO(2), and...
A chemically defined medium was developed for the production of intracellular malate dehydrogenases by Streptomyces aureofaciens NRRL-B 1286. The composition of the medium (per liter) was as follows: 50 g of starch, 4 g of ammonium sulfate, 7.32 g of l-aspartic acid, 13.8 g of MgSO(4) . 7H(2)O, 1.7 g of K(2)HPO(4), 0.0...