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Enrichment cultures of phototrophic purple bacteria rapidly oxidized up to 10 mM dimethyl sulfide (DMS) to dimethyl sulfoxide (DMSO). DMSO was qualitatively identified by proton nuclear magnetic resonance. By using a biological assay, DMSO was always quantitatively recovered from the culture media. DMS oxidation was no... |
d-Xylose is a plentiful pentose sugar derived from agricultural or forest residues. Enteric bacteria such as Klebsiella spp. ferment d-xylose to form mixed acids and butanediol in addition to ethanol. Thus the ethanol yield is normally low. Zymomonas spp. and most yeasts are unable to ferment xylose, but they do fermen... |
Oscillatoria terebriformis, a thermophilic cyanobacterium, carried out a diel vertical movement pattern in Hunter's Hot Springs, Oreg. Throughout most daylight hours, populations of O. terebriformis covered the surface of microbial mats in the hot spring outflows below an upper temperature limit of 54 degrees C. Upon d... |
Several benthic cyanobacteria were found to produce significant amounts of extracellular flocculants. The macromolecular flocculants produced by Phormidium sp. strain J-1 and Anabaenopsis circularis PCC 6720 were characterized. The Phormidium flocculant is a sulfated heteropolysaccharide to which fatty acids and protei... |
Comparative analysis by sodium dodecyl sulfate-polyacrylamide gel electrophoresis of culture supernatants of a virulent Pseudomonas solanacearum strain and of a spontaneous avirulent mutant derived from it was performed. The results show that the levels of two major polypeptides with molecular masses of 43 and 25 kilod... |
The seasonal variation in temperature characteristics of photosynthetic and heterotrophic activities in the microbial plankton of Bedford Basin, Nova Scotia, was investigated. Measurements were made of the photosynthetic uptake of [C]bicarbonate and its incorporation into cellular protein as well as the heterotrophic u... |
During the ripening of Gouda-type cheese, two kinds of endopeptidases were found to participate in the degradation of alphas1-CN(f1-23), a specific product from alphas1-casein hydrolyzed by chymosin. One of the endopeptidases, lactic acid bacteria endopeptidase (LEP-II), which can recognize the size of its substrates, ... |
The phytopathogenic enterobacterium Erwinia chrysanthemi strain EC16 produces four isozymes of pectate lyase (PL), an extracellular enzyme that macerates parenchymatous plant tissues and kills plant cells. A 1.8-kilobase EcoRI DNA fragment containing the entire pelE gene was deleted from the E. chrysanthemi chromosome ... |
Viable-bacteria counts, heterotrophic activity, and substrate responsiveness of viable bacteria have been used to measure microbial activity. However, the relationship between these parameters is not clear. Thus, the direct viable count (DVC) method was used to analyze seawater samples collected from several different ... |
Using an anti-lignin peroxidase antiserum-protein A-gold complex, we found lignin peroxidase mainly intracellularly in several white rot fungi colonizing sawdust under laboratory conditions. This enzyme was also present in fungi found in naturally decayed wood. However, in all cases, lignin peroxidase was located mainl... |
When monomethylamine was the growth substrate, spontaneous disaggregation of Methanosarcina mazei S-6 commenced at the mid-exponential phase and resulted in the formation of a suspension containing 10 to 10 free cells per ml. Free cells were osmotically fragile and amenable to extraction of DNA. Hypertonic media for th... |
When the plasmid pSa is introduced into Agrobacterium tumefaciens, its presence results in the suppression of bacterial virulence. A. tumefaciens(pSa) cells are virulent on Bryophyllum diagremontiana only when inoculated with auxin. A. tumefaciens(pSa) cells also bind to plant cells only in the presence of auxin. The e... |
Methanosarcina barkeri was cultured on methanol, H(2)-CO(2), and acetate, and the C/C ratios of the substrates and the methane produced from them were determined. The discrimination against C in methane relative to substrate decreased in the order methanol > CO(2) > acetate. The isotopic fractionation for methane deriv... |
Mechanisms for inhibition of sulfate reduction and methane production in the zone of Fe(III) reduction in sediments were investigated. Addition of amorphic iron(III) oxyhydroxide to sediments in which sulfate reduction was the predominant terminal electron-accepting process inhibited sulfate reduction 86 to 100%. The d... |
Serological techniques and restriction enzyme cleavage patterns of total DNA were used to differentiate strains of Agrobacterium spp. Forty-five wild-type and plasmid-cured Agrobacterium strains were tested by immunodiffusion and immunofluorescence against polyclonal antisera to a crude ribosome preparation from Agroba... |
The wild-type ligninolytic actinomycete Streptomyces viridosporus T7A and two genetically manipulated strains with enhanced abilities to produce a water-soluble lignin degradation intermediate, an acid-precipitable polymeric lignin (APPL), were grown on lignocellulose in solid-state fermentation cultures. Culture filtr... |
Spontaneous mutants of Clostridium acetobutylicum NRRL B643 that were resistant to allyl alcohol (AA) were selected and characterized. These mutants contained 10- to 100-fold reduced activities of butanol and ethanol alcohol dehydrogenase. The AA mutants formed two groups and produced no ethanol. Type 1 AA mutants prod... |
Clostridium thermocellum JW20 and YM4 both synthesize cellulolytic enzyme complexes, cellulosomes, when grown on medium containing cellulose. Electron microscopic studies showed that, in the early stages of growth of strain JW20, clusters of tightly packed cellulosomes, i.e., polycellulosomes, were located on the cell ... |
The red yeast Rhodotorula mucilaginosa produced an esterase that accumulated in the culture supernatant on induction with triacetin. The enzyme was specific for substrates bearing an O-acetyl group, but was relatively nonspecific for the rest of the molecule, which could consist of a phenol, a monosaccharide, a polysac... |
Extracellular enzyme preparations from Streptomyces flavogriseus and Streptomyces olivochromogenes cultures grown on cellulose contained primarily cellulase activities, but similar preparations from cultures grown on xylan-containing materials possessed high levels of both cellulase and xylanase activities. Growth cond... |
Coriolus versicolor has previously been shown to degrade leonardite, an oxidized form of lignite. An extracellular fraction containing protein purified from a C. versicolor culture solubilized leonardite in vitro. Expression of the activity did not require the presence of leonardite and appeared during idiophase. Durin... |
The critical assumptions of the dilution method for estimating grazing rates of microzooplankton were tested by using a community from the sediment-water interface of Lake Anna, Va. Determination of the appropriate computational model was achieved by regression analysis; the exponential model was appropriate for bacter... |
ASSAY OF CELLULASE ENZYMOLOGY ON CELLULOSE WAS INVESTIGATED BY TWO METHODS: (i) plate colony counting to determine microbial growth and (ii) microbial calorimetry. These methods were chosen because they accept raw samples and have the potential to be far more specific than spectrophotometric reducing sugar assays. Micr... |
Several enzymatic properties of an endoglucanase produced in Escherichia coli by a gene from Pseudomonas fluorescens subsp. cellulosa were investigated. Gel filtration revealed a single peak of M(r) 36,000 with endoglucanase activity. The pH optimum of the enzyme was 7.0. Carboxymethyl cellulose and barley beta-glucan ... |
The effect of 5-fluoro-2'-deoxyuridine (FdUrd) on [methyl-H] thymidine incorporation by bacterioplankton populations in subtropical freshwater, estuarine, and oceanic environments was examined. In estuarine waters, intracellular isotope dilution was inhibited by FdUrd, which enabled us to estimate both intracellular an... |
The reaction pathway from squalene to trans-geranylacetone in Arthrobacter sp. strain Y-11 was studied. The enzyme or enzymes catalyzing squalene degradation were found to be membrane bound. Stoichiometric analysis of a cell-free system revealed that the ratio of squalene to trans-geranylacetone changed from 1:2 to 1:1... |
A mathematical model composed of a direct proportionality relationship between bulk water velocities and field-determined second-order microbial transformation rate coefficients, and the relative rate coefficient of a benchmark chemical, was developed for estimating the substrate removal rates of rapidly degraded chemi... |
Thermoanaerobacter ethanolicus (ATCC 31550) has primary and secondary alcohol dehydrogenases. The two enzymes were purified to homogeneity as judged from sodium dodecyl sulfate-polyacrylamide gel electrophoresis and gel filtration. The apparent M(r)s of the primary and secondary alcohol dehydrogenases are 184,000 and 1... |
Veratryl alcohol, added as a supplement to cultures of Phanerochaete chrysosporium, enhanced ligninase activity through protection of the ligninase against inactivation by hydrogen peroxide produced by this fungus in cultures. In the presence of veratryl alcohol, the loss of ligninase activity observed in non-protein-s... |
Mannose is not a suitable substrate for N(2)-fixing Azotobacter vinelandii. However, when H(2) gas is provided, A. vinelandii can grow mixotrophically with H(2) as the energy source and mannose as the carbon source (T.-Y. Wong and R. J. Maier, J. Bacteriol. 163:528-533, 1985). In this report, seven sugars were used to ... |
We used the yeast MEL1 gene for secreted alpha-galactosidase to construct cartridges for the regulated expression of foreign proteins from Saccharomyces cerevisiae. The gene for a Cellulomonas fimi beta-1,4-exoglucanase was inserted into one cartridge to create a fusion of the alpha-galactosidase signal peptide to the ... |
O-methylation of 2,6-dibromophenol was studied in cell extracts prepared from Rhodococcus sp. strain 1395. O-methylation activity was enhanced by the addition of S-adenosyl-l-methionine but was not affected by the addition of 5-methyltetrahydrofolate nor by up to 10 mM MgCl(2) or EDTA. By using 2,6-dibromophenol, 4,5,6... |
The cell-free isobutene-forming system of Rhodotorula minuta IFO 1102 was prepared. This system consisted of isovaleric acid, NADPH, and a cell extract. The maximal activity obtained by using the described cell-free system was 17 nl/mg of protein per h. It appears that this cell-free isobutene-forming system operates i... |
Three microtitration plate enzyme-linked immunosorbent assays (ELISAs) have been developed: a competitive ELISA and a two-site (or indirect sandwich) ELISA for Methanosarcina mazei S6 and a two-site ELISA for Methanobacterium bryantii FR-2. The assays were sensitive, with limits of cell protein detection of 3 ng ml, 5 ... |
The temperate bacteriophage BK5-T was isolated from Streptococcus cremoris BK5 by induction with mitomycin C. Electron microscopy revealed that BK5-T DNA consists of linear molecules, ranging in size from 39.7 to 46 kilobase pairs. Restriction analysis of self-ligated BK5-T DNA showed that the ends of the DNA were not ... |
The ability of three strains of Lactobacillus acidophilus to survive and retain beta-galactosidase activity during storage in liquid nitrogen at -196 degrees C and during subsequent storage in milk at 5 degrees C was tested. The level of beta-galactosidase activity varied among the three strains (0.048 to 0.177 U/10 or... |
Trichloroethylene (TCE), a common groundwater contaminant, is a suspected carcinogen that is highly resistant to aerobic biodegradation. An aerobic, methane-oxidizing bacterium was isolated that degrades TCE in pure culture at concentrations commonly observed in contaminated groundwater. Strain 46-1, a type I methanotr... |
A d-aminoacylase-producing microorganism, strain DA181, isolated from soil was identified as Alcaligenes denitrificans subsp. denitrificans. This strain produced about 29,300 units (micromoles of product formed per hour) of d-aminoacylase and 2,300 units of l-aminoacylase per gram of cells (wet weight) when cultivated ... |
From a screening of several Kluyveromyces strains, the yeast Kluyveromyces marxianus CBS 6556 was selected for a study of the parameters relevant to the commercial production of inulinase (EC 3.2.1.7). This yeast exhibited superior properties with respect to growth at elevated temperatures (40 to 45 degrees C), substra... |
Schizophyllum commune produced an esterase which released ferulic acid from starch-free wheat bran and from a soluble ferulic acid-sugar ester that was isolated from wheat bran. The preferred growth substrate for the production of ferulic acid esterase was cellulose. Growth on xylan-containing substrates (oat spelt xyl... |
Intergeneric protoplast fusion between Ruminococcus albus, a cellulolytic, gram-positive, anaerobic bacterium (Pc Sm Km), and an anaerobic recombinant, FE7 (Pc Sm Km), having lignin-related compound-degrading activities, was performed under strictly anaerobic conditions to introduce cellulase genes into strain FE7. The... |
Temperature and hydrostatic pressure are essential in determining the assemblage of species in their specific biotopes. To evaluate the effect of high pressure on the range of viability of thermophiles, the pressure and temperature dependence of the growth of the methanogenic archaebacterium Methanococcus thermolithotr... |
Both the periplasmic and the extracellular cellodextrinases from Bacteroides succinogenes S85 grown on Avicel microcrystalline cellulose were purified to homogeneity by column chromatography and characterized. Over 70% of the total cellobiosidase activity displayed by cells was accounted for by these enzymes. The perip... |
In water column and sediment inocula from a nuclear reactor cooling reservoir, natural phytoplankton substrate labeled with C was used to determine aerobic and anaerobic mineralization rates for a range of temperatures (25, 40, 55, and 70 degrees C) expected during reactor operation. For experiments that were begun dur... |
A newly isolated bacterium, identified as Bacillus subtilis 65, was found to produce raw-starch-digesting alpha-amylase. The electrophoretically homogeneous preparation of enzyme (molecular weight, 68,000) digested and solubilized raw corn starch to glucose and maltose with small amounts of maltooligosaccharides rangin... |
Nitrogen fixation (diazotrophy) has recently been demonstrated in several methanogenic archaebacteria. To compare the process in an archaebacterium with that in eubacteria, we examined the properties of diazotrophic growth and nitrogenase activity in Methanosarcina barkeri 227. Growth yields with methanol or acetate as... |
The mechanisms of utilization of DNA by estuarine microbial populations were investigated by competition experiments and DNA uptake studies. Deoxyribonucleoside monophosphates, thymidine, thymine, and RNA all competed with the uptake of radioactivity from [H]DNA in 4-h incubations. In 15-min incubations, deoxyribonucle... |
Screening of leachable toxic chemicals in a horseradish peroxidase-H(2)O(2) immobilization system established that immobilization was promising for most phenolic pollutants but not for benzoic acid, 2,6-dinitrocresol, or dibutyl phthalate. The treatment did not mobilize inherently nonmobile pollutants such as anilines ... |
Nitrile hydratase, which occurs abundantly in cells of Rhodococcus rhodochrous J1 isolated from soil samples, catalyzes the hydration of 3-cyanopyridine to nicotinamide. By using resting cells, the reaction conditions for nicotinamide production were optimized. Under the optimum conditions, 100% of the added 12 M 3-cya... |
A genomic library of Ruminococcus albus 8 DNA was constructed by using the Escherichia coli bacteriophage lambdaDASH. Recombinants were screened for cellulolytic activity by plating in soft agar (0.7%) overlays containing either 1% (wt/vol) carboxymethyl cellulose (CMC), 4-methylumbelliferyl-beta-d-cellobioside (MUC, 1... |
A gene for 2,5-diketo-d-gluconate (25DKG) reductase, which encodes an enzyme composed of 277 amino acid residues catalyzing the reduction of 25DKG to 2-keto-l-gulonate (2KLG), was cloned from Corynebacterium sp. strain SHS752001 and expressed in Erwinia citreus SHS2003, a strain which oxidizes glucose to 25DKG. The rec... |
Nine phenolic compounds were metabolized by the soft rot fungus Lecythophora hoffmannii via protocatechuic acid and subsequently cleaved by protocatechuate 3,4-dioxygenase as determined by oxygen uptake, substrate depletion, and ring cleavage analysis. Catechol was metabolized by catechol 1,2-dioxygenase. Fungal utiliz... |
We examined the simultaneous incorporation of [H]thymidine and [C]leucine to obtain two independent indices of bacterial production (DNA and protein syntheses) in a single incubation. Incorporation rates of leucine estimated by the dual-label method were generally higher than those obtained by the single-label method, ... |
The response of Clostridium acetobutylicum ATCC 4259 to the stresses produced by a temperature upshift from 28 degrees C to 45 degrees C and by exposure of the organisms to 0.1% n-butanol or to air was examined by analysis of pulse-labeled proteins. The stress response was the induction of the synthesis of a number of ... |
We have investigated the protein composition and the insecticidal spectrum of crystals of 29 Bacillus thuringiensis strains active against lepidopteran larvae. All crystals contained proteins of 130 to 140 kilodaltons (kDa) which could be grouped into three types by the molecular weight of the protoxin and the trypsin-... |
Our experiments with selected organic substrates reveal that the rate-limiting process governing microbial degradation rates changes with substrate concentration, S, in such a manner that substrate removal is enhanced at lower values of S. This enhancement is the result of the dominance of very efficient systems for su... |
The morphology of Methanosarcina mazei was controlled by magnesium, calcium, and substrate concentrations and by inoculum size; these factors allowed manipulation of the morphology and interconversions between pseudosarcinal aggregates and individual, coccoid cells. M. mazei grew as aggregates in medium with a low conc... |
A catalase-negative mutant of the yeast Hansenula polymorpha consumed methanol in the presence of glucose when the organism was grown in carbon-limited chemostat cultures. The organism was apparently able to decompose the H(2)O(2) generated in the oxidation of methanol by alcohol oxidase. Not only H(2)O(2) generated in... |
Caulobacters are prosthecate (stalked) bacteria that elaborate an attachment organelle called a holdfast at the tip of the cellular stalk. We examined the binding of lectins to the holdfasts of 16 marine Caulobacter strains and 10 freshwater species or strains by using a panel of fluorescein-conjugated lectins and fluo... |
beta-Glucosidase activity in Myceliophthora thermophila D-14 (= ATCC 48104) was inducible and was produced in culture filtrate during growth with various inducers, of which PNPG (p-nitrophenyl-beta-d-glucoside) was the most efficient. Induction of beta-glucosidase also occurred when the organism was grown in medium sup... |
The lignocellulose-degrading actinomycete Streptomyces viridosporus T7A produced an extracellular esterase when grown in a mineral salts-yeast extract medium. Extracellular esterase activity was first detected during the late stationary phase and typically followed the appearance of intracellular activity. When the org... |
Twelve monoclonal antibodies directed to the cell-wall-associated proteinase of Lactococcus lactis subsp. cremoris Wg2 were isolated after immunization of BALB/c mice with a partially purified preparation of the proteinase. The monoclonal antibodies reacted with the 126-kilodalton proteinase band in a Western immunoblo... |
alpha-Amylase production was examined in the ruminal anaerobic fungus Neocallimastix frontalis. The enzyme was released mainly into the culture fluid and had temperature and pH optima of 55 degrees C and 5.5, respectively, and the apparent K(m) for starch was 0.8 mg ml. The products of alpha-amylase action were mainly ... |
Elevated hydrostatic pressure has been shown to affect the growth rate of the thermophilic methanobacterium Methanococcus thermolithotrophicus without extending its temperature range of viability. Analysis of the cell inventory after approximately 10 h of incubation at 65 degrees C and 50 MPa (applying high-pressure li... |
Yeast strains capable of fermenting starch and dextrin to ethanol were isolated from samples collected from Brazilian factories in which cassava flour is produced. Considerable alcohol production was observed for all the strains selected. One strain (DI-10) fermented starch rapidly and secreted 5 times as much amylolyt... |
The production of enniatins by Fusarium scirpi during fermentative growth in submerged cultures was measured. The fungus produced the antibiotic during mycelial growth, but not during the stationary phase of cultivation. By contrast, enniatin synthetase, the enzyme responsible for enniatin synthesis, was present during... |
Thermomonospora fusca YX grown in the presence of cellulose produces a number of beta-1-4-endoglucanases, some of which bind to microcrystalline cellulose. By using a multicopy plasmid, pIJ702, a gene coding for one of these enzymes (E2) was cloned into Streptomyces lividans and then mobilized into both Escherichia col... |
At least three different insecticidal crystal protein genes were shown to be expressed in Bacillus thuringiensis subsp. aizawai 7.29, a strain that is potentially active against the cotton leafworm Spodoptera littoralis Bdv. Among crude K-60 fractions (60- to 70-kilodalton [kDa] molecules) that were products of proteol... |
To better understand temporal variability in soil denitrification, denitrifying enzyme activity (DEA) and denitrifier populations (as determined by most-probable-number [MPN] counts) were measured in field and laboratory experiments. Measurements of DEA and MPN provided highly contradictory indications of denitrifier d... |
Thiolase (acetyl-coenzyme A [CoA] acetyltransferase, E.C. 2.3.1.19) from Clostridium acetobutylicum ATCC 824 has been purified 70-fold to homogeneity. Unlike the thiolase in Clostridium pasteurianum, this thiolase has high relative activity throughout the physiological range of internal pH of 5.5 to 7.0, indicating tha... |
There is indirect evidence that soil microorganisms producing ethylene (C(2)H(4)) can influence plant growth and development, but unequivocal proof is lacking in the literature. A laboratory study was conducted to demonstrate the validity of this speculation. Four experiments were carried out to observe the characteris... |
A bacterial strain that produces d-aminoacylase was isolated from soil and identified as Alcaligenes denitrificans subsp. xylosoxydans MI-4. l-Aminoacylase activity in this strain was only 1 to 2% of d-aminoacylase activity. d-Aminoacylase was inducibly produced. N-Acetyl-dl-leucine was the best inducer, and the d-isom... |
Xenorhabdus luminescens Hm cultured in gelatin broth produced a single extracellular protease. The protease was purified by a factor of 500 and characterized as a monomeric protein with an approximate molecular weight of 61,000. On the basis of inhibitor studies and its pH optimum, the protease was classified as an alk... |
A thermostable pullulanase (alpha-dextrin 6-glucanohydrolase [EC 3.2.1.41]) from a newly isolated Bacillus stearothermophilus strain (TRS128) was purified and characterized. The enzyme hydrolyzed (1-->6)-alpha-d-glucosidic linkages of pullulan to produce maltotriose, and the optimum temperature was 65 degrees C. About ... |
Cells of the strictly aerobic Acinetobacter strain 210A, containing aerobically large amounts of polyphosphate (100 mg of phosphorus per g [dry weight] of biomass), released in the absence of oxygen 1.49 mmol of P(i), 0.77 meq of Mg, 0.48 meq of K, 0.02 meq of Ca, and 0.14 meq of NH(4) per g (dry weight) of biomass. Th... |
Methanogenic bacteria growing on a pilot-scale, anaerobic filter processing coal gasification waste were enriched in a mineral salts medium containing hydrogen and acetate as potential energy sources. Transfer of the enrichments to methanol medium resulted in the initial growth of a strain of Methanosarcina barkeri, bu... |
In membranes of Rhizobium leguminosarum bacteroids isolated from nitrogen-fixing pea root nodules, two different protein complexes with NADH dehydrogenase activity were detected. One of these complexes, with a molecular mass of 110 kilodaltons, was also found in membranes of free-living rhizobia, but the other, with a ... |
The marine archaebacterium Methanococcus jannaschii was studied at high temperatures and hyperbaric pressures of helium to investigate the effect of pressure on the behavior of a deep-sea thermophile. Methanogenesis and growth (as measured by protein production) at both 86 and 90 degrees C were accelerated by pressure ... |
The characteristics of the obligate alkalophilic Bacillus sp. strain Ya-B, which produces alkaline elastase extracellularly, were examined. This strain grew at pH 7.0 only in the presence of 1% or more NaCl. Its fatty acid distribution pattern was similar to that of other Bacillus species in which iso-C(15) and anteiso... |
The conjugative 450-kilobase-pair megaplasmid pHG1 from Alcaligenes eutrophus H16 was transferred to the herbicide-degrading soil bacterium A. eutrophus JMP134. This transfer was achieved by means of RP4 mobilization and a Tn5-Mob insertion provided in trans on the megaplasmid replicon. Although kanamycin-resistant tra... |
The kinetics of xylose uptake were investigated in the efficient xylose fermenter Pichia stipitis and in the more readily genetically manipulated, strictly respiratory yeast Pichia heedii. Both yeasts demonstrated more than one xylose uptake system, differing in substrate affinity. The K(m) of high-affinity xylose upta... |
Acetyl coenzyme A (acetyl-CoA) synthetase and acetate kinase were localized within the soluble portion of Bradyrhizobium japonicum bacteroids, and no appreciable activity was found elsewhere in the nodule. The presence of each acetate-activating enzyme was confirmed by separation of the two enzyme activities on a hydro... |
A genomic clone bank of Acetobacter polyoxogenes NBI1028 constructed in Escherichia coli by use of the expression vector pUC18 was screened with antibody raised against membrane-bound aldehyde dehydrogenase (ALDH; 75 kilodaltons [kDa]) from A. polyoxogenes NBI1028. A clone that synthesized a 41-kDa protein cross-reacti... |
A laminarinase [endo-(1,3)-beta-d-glucanase] has been purified from Trichoderma longibrachiatum cultivated with d-glucose as the growth substrate. The enzyme was found to hydrolyze laminarin to oligosaccharides varying in size from glucose to pentaose and to lesser amounts of larger oligosaccharides. The enzyme was una... |
The potential for biological nitrification of an industrial waste containing 4,000 mg of ammonia N (NH(4)-N) and 10,000 mg of fluoride per liter was investigated. Ammonium sulfate and sodium fluoride were tested in various combinations of 100 to 2,000 mg of NH(4)-N per liter and 0 to 5,000 mg of F per liter in suspende... |
Azotobacter vinelandii OP was grown to stationary phase in defined medium. The cell-free culture medium was analyzed for cytokinin content by XAD-2 and Sephadex LH-20 chromatography, thin-layer chromatography, tobacco callus bioassay, and enzyme immunoassay. Three cytokinin-active fractions were detected and tentativel... |
Soil denitrification is a highly variable process that appears to be lognormally distributed. This variability is manifested by large sample coefficients of variation for replicate estimates of soil core denitrification rates. Deterministic models for soil denitrification have been proposed in the past, but none of the... |
Acidophilic iron-oxidizing bacteria were enriched from mine water samples with ferrous sulfate as the substrate at incubation temperatures in the range of 4 to 46 degrees C. After several subcultures at each test temperature except 46 degrees C, which was prohibitive to growth, the rates of iron oxidation were determin... |
Swollen basidiospores of an adenine auxotroph of Phanerochaete chrysosporium were protoplasted with Novozyme 234 and transformed to prototrophy by using a plasmid containing the gene for an adenine biosynthetic enzyme from Schizophyllum commune. Transformation frequencies of 100 transformants per mug of DNA were obtain... |
A facultative alkalophile capable of utilizing 4-chlorobenzoate (4-CBA), strain SB8, was isolated from soil with an alkaline medium (pH 10.0) containing the haloaromatic compound as the carbon source. The strain, identified as an Arthrobacter sp., showed rather extensive 4-CBA-degrading ability. 4-CBA utilization by th... |
The kinetics of acetate utilization were examined for washed concentrated cell suspensions of two thermophilic acetotrophic methanogens isolated from a 58 degrees C anaerobic digestor. Progress curves for acetate utilization by cells of Methanosarcina sp. strain CALS-1 showed that the utilization rate was concentration... |
Aerobic, carbon-limited, enrichment cultures containing 3-aminobenzenesulfonate or 3-nitrobenzenesulfonate as the sole source of carbon and energy yielded growth and complete substrate disappearance. Pure cultures of putative pseudomonads were isolated which utilized these compounds quantitatively. Degradation was comp... |
The possibility of using the nutritionally versatile bacterium Pseudomonas cepacia to produce poly-beta-hydroxyalkanoic acid was evaluated. Chemostat culture showed that growth of P. cepacia became nitrogen limited when the molar carbon-to-nitrogen ratio of the medium fed into the fermentor was above 15. When grown und... |
The biodegradation of hydroxybenzoate isomers was investigated with samples obtained from two sites within a shallow anoxic aquifer. The metabolic fates of the substrates were compared in denitrifying, sulfate-reducing, and methanogenic incubations. Under the latter two conditions, phenol was detected as a major interm... |
When Bradyrhizobium japonicum I-110 was transferred into medium containing 40 mM succinate or 40 mM fumarate, over 90% of the bacteria acquired a swollen, pleomorphic form similar to that of bacteroids. The induction of pleomorphism was dependent on the carbon substrate and concentration but was independent of the hydr... |
A beta-amylase-overproducing mutant of Clostridium thermosulfurogenes was grown in continuous culture on soluble starch to produce thermostable beta-amylase. Enzyme productivity was reasonably stable over periods of weeks to months. The pH and temperature optima for beta-amylase production were pH 6.0 and 60 degrees C,... |
An immunoblotting procedure was developed to overcome the difficulty in identifying root colonization by a vesicular-arbuscular mycorrhizal fungus. The procedure utilized a murine monoclonal antibody that reacts with a protein in spores and hyphae of Glomus occultum, a fungus characterized by abundant production of hya... |
The distribution of lignin peroxidase during degradation of both wood and woody fragments by the white rot fungus Phanerochaete chrysosporium was investigated by using anti-lignin peroxidase in conjunction with postembedding transmission electron microscopy and immuno-gold labeling techniques. The enzyme was localized ... |
Sluggish and stuck (i.e., very delayed or incomplete) fermentations have been often observed in wine making. Some of them appeared to be associated with insufficient levels of yeast nutrients such as assimilable nitrogen. In these conditions, sugar transport catabolite inactivation, which is triggered by the protein sy... |
Two bacterial strains were dominant in anaerobic enrichment cultures with betaine (N,N,N-trimethylglycine) as a substrate and intertidal mud as an inoculum. One was a coccoid bacterium which was a trimethylamine (TMA)-fermenting methanogen similar to Methanococcoides methylutens. The other strain, a rod-shaped, gram-ne... |
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