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Characteristics of an obligately methylotrophic coccoid methanogen (strain GS-16) previously isolated from estuarine sediment are described. Growth was demonstrated on dimethyl sulfide (DMS) or trimethylamine (TMA), but not on methane thiol, methane thiol plus hydrogen, dimethyl disulfide, or methionine. DMS-grown cell...
A highly polymorphic Xenorhabdus luminescens strain was isolated. The primary form of X. luminescens was luminescent and nonswarming and produced a yellow pigment and antimicrobial substances. The primary form generated a secondary form that had a distinct orange pigmentation, was weakly luminescent, and did not produc...
Zinc was extracted from a filter residue of a copper works (58.6% zinc) by a Penicillium sp. isolated from a metal-containing location. By isotachophoresis citric acid was identified as the leaching agent. Citrate was only formed when the leaching substrate was present. This production of citrate was different in sever...
Streptomyces viridosporus T7A and S. badius 252 were grown in 1 to 2% (wt/vol) slurry cultures with mineral salts solution containing 0.6% yeast extract and 100/200 mesh ground and extracted corn lignocellulose at 37 degrees C. Enzyme activities rapidly increased in the first 3 to 4 days and then declined and remained ...
The affinity of Methanosarcina barkeri 227 for acetate and hydrogen at different incubation temperatures was investigated. Increasing the temperature from 20 to 37 degrees C resulted in a 4.5-fold increase in K(m) for acetate and a 4.8-fold increase for hydrogen. The corresponding increase in V(max) for acetate was 8.3...
Thymidine uptake and incorporation by marine bacterial isolates from an upwelling environment were studied. Of 17 isolates each from upwelled and downwelled water, 1 and 6 isolates, respectively, were found to be negative for [H]thymidine incorporation at a substrate concentration of 19 muM. Strains lacking the ability...
A method is described for the purification of Bacillus thuringiensis protein crystals by Ludox gradient centrifugation. This method is simple, inexpensive, fast, and efficient compared with other techniques. It has been successfully used to purify and characterize the protein crystals from several B. thuringiensis stra...
The progressive decline in the glycolytic activity of Saccharomyces cerevisiae during batch fermentation is accompanied by changes in adenine nucleotide pools. The relative activities of four glycolytic enzymes were examined in vitro in the presence of nucleotide concentrations equivalent to intracellular pools. Phosph...
Examination of cucumber roots (Cucumis sativus L.) grown in bark compost media and of the surrounding edaphic substrate showed profiles of polar lipid fatty acids commonly found in bacteria. The composition of fatty acids in these profiles differed significantly between roots grown in a medium naturally suppressive to ...
The white rot fungi used in this study caused two different forms of degradation. Phanerochaete chrysosporium, strain BKM-F-1767, and Phellinus pini caused a preferential removal of lignin from birch wood, whereas Trametes (Coriolus) versicolor caused a nonselective attack of all cell wall components. Use of polyclonal...
The regulation of trichodiene synthase (TS) and its relationship to trichothecene biosynthesis was investigated in Fusarium sporotrichioides NRRL 3299 and Gibberella pulicaris R-6380. Cultures were analyzed for the presence of TS activity, trichothecenes, and immunodetectable TS polypeptide over a time period of 144 h....
During three periods of 16 to 25 days, bacterioplankton production, bacterial cell volume, chlorophyll a, CO(2) assimilation, and particulate organic carbon were measured in enclosures situated in the eutrophic estuary Roskilde Fjord, Denmark. The enclosures were manipulated with respect to sediment contact and content...
Subcultures of Pseudomonas putida R5-3 altered their plasmid DNA content in specific ways depending on the particular aromatic hydrocarbon utilized as the sole carbon source. Two indigenous plasmids, 115 and 95 kilobases (kb) in size, were observed in R5-3A, which was derived from R5-3 by growth on minimal medium conta...
Growth and concomitant production of an extracellular pectin lyase (PL) [poly(methoxylgalactosiduronate) endolyase; EC 4.2.2.10] were investigated in a group of 16 fungi grown in liquid medium containing pectin as a supplementary carbon source. Culture filtrates of both Penicillium italicum (CECT 2294) and P. expansum ...
Lactobacillus bulgaricus CNRZ 397 is able to hydrolyze many amino-acyl- and dipeptidyl-beta-naphthylamides. Analysis of heat inactivation kinetics, protease inhibitor effects, and the subcellular location of aminopeptidase (AP) activities from the parental strain and mutant derivatives dificient in alanyl- or leucyl-be...
Experiments were conducted to (i) compare most-probable-number (MPN) procedures with roll tube procedures for enumeration of forage anaerobic bacteria and (ii) evaluate the efficacy of using ethylene oxide to sterilize wet herbage. Alfalfa, corn, and alfalfa-orchardgrass silages and alfalfa and orchardgrass herbages we...
Acetobacterium woodii formed ethanol as a fermentation product in addition to acetate when the phosphate concentration of the medium was between 0.2 and 8.4 mM. Considerable amounts of alanine were also found (2 to 11 mM). Supplementation with phosphate caused a shift to acetate as the only end product. Ethanol could a...
The seasonal variation and depth distribution of the capacity for denitrification and dissimilatory NO(3) reduction to NH(4) (NO(3) ammonification) were studied in the upper 4 cm of the sediment of Norsminde Fjord estuary, Denmark. A combination of C(2)H(2) inhibition and N isotope techniques was used in intact sedimen...
Temperature and aeration shifts were used to perturb steady-state continuous cultures to determine the effects of ethanol on xylose metabolism by Candida shehatae. The accumulation of ethanol exerted a delayed inhibitory effect on the specific rate of substrate utilization. A second effect was also observed in which th...
A bacterium capable of utilizing high concentrations of acetonitrile as the sole source of carbon and nitrogen was isolated from soil and identified as Pseudomonas putida. This bacterium could also utilize butyronitrile, glutaronitrile, isobutyronitrile, methacrylonitrile, propionitrile, succinonitrile, valeronitrile, ...
An aminopeptidase was purified from cell extracts of Lactococcus lactis subsp. cremoris AM2 by ion-exchange chromatography. After electrophoresis of the purified enzyme in the presence or absence of sodium dodecyl sulfate, one protein band was detected. The enzyme was a 300-kilodalton hexamer composed of identical subu...
The cellulose-producing bacterium Acetobacter xylinum has been considered a strict aerobe, and it has been suggested that the function of cellulose is to hold cells in an aerobic environment. In this study, we showed that A. xylinum is capable of growing microaerophilically. Cellulose pellicles provided significant pro...
Cell extracts of Cenococcum graniforme have been found to contain the following hydrolytic enzymes: protease, esterase, alpha-d-galactopyranosidase, beta-d-galactopyranosidase, alpha-d-mannopyranosidase, beta-d-xylopyranosidase, alpha-d-glucopyranosidase, beta-d-glucopyranosidase, and alkaline phosphatase. Sulfatase, i...
Among 180 Streptomyces strains tested, 25 were capable of hydrolyzing microcrystalline cellulose (Avicel) at 30 degrees C. Streptomyces reticuli was selected for further studies because of its ability to grow at between 30 and 50 degrees C on Avicel. Enzymatic activities degrading Avicel, carboxymethyl cellulose, and c...
A stable hybrid obtained by protoplast fusion between a Cellulomonas sp. and Bacillus subtilis exhibits an altered pattern of enzyme induction with different cellulosic substrates. Unlike in the Cellulomonas sp., xylanase was induced in the hybrid organism specifically by xylan, and endoglucanase was induced by carboxy...
DNA, RNA, and protein concentrations from starved ANT-300 cell populations grown at different growth rates fluctuated corresponding to the three stages of starvation-survival on total and viable cell bases. During stage 1 of starvation-survival, two to three peaks in the concentration levels for all three macromolecule...
A host-vector system for inducible secretion during the logarithmic growth phase in Bacillus subtilis has been developed. The B. subtilis levansucrase gene promoter and the region encoding its signal sequence have been used. The endoglucanase A of Clostridium thermocellum was used as a model protein to test the efficie...
The substrate specificity of the DNA-binding mechanism(s) of bacteria in a Florida reservoir was investigated in short- and long-term uptake studies with radiolabeled DNA and unlabeled competitors. Thymine oligonucleotides ranging in size from 2 base pairs to 19 to 24 base pairs inhibited DNA binding in 20-min incubati...
Styrene oxide and 2-phenylethanol metabolism in the styrene-degrading Xanthobacter sp. strain 124X was shown to proceed via phenylacetaldehyde and phenylacetic acid. In cell extracts 2-phenylethanol was oxidized by a phenazine methosulfate-dependent enzyme, probably a pyrroloquinoline quinone enzyme. Xanthobacter sp. s...
Aerobic and anaerobic groundwater continuous-flow microcosms were designed to study nitrate reduction by the indigenous bacteria in intact saturated soil cores from a sandy aquifer with a concentration of 3.8 mg of NO(3)-N liter. Traces of NO(3) were added to filter-sterilized groundwater by using a Darcy flux of 4 cm ...
Induced mutants, selected for their defective growth on d-xylose while retaining the ability to grow normally on d-glucose, were studied in Pachysolen tannophilus, a yeast capable of converting d-xylose to ethanol. Fourteen of the mutations were found to occur at nine distinct loci, and data indicated that many more lo...
Strain DM1, a Mycobacterium sp. that utilizes 2,6-xylenol, 2,3,6-trimethylphenol, and o-cresol as sources of carbon and energy, was isolated. Intact cells of Mycobacterium strain DM1 grown with 2,6-xylenol cooxidized 2,4,6-trimethylphenol to 2,4,6-trimethylresorcinol. 4-Chloro-3,5-dimethylphenol prevents 2,6-xylenol fr...
Filamentous bacteria, identified as members of the genus Beggiatoa by gliding motility and internal globules of elemental sulfur, occur in massive aggregations at the deep-sea hydrothermal vents of the Guaymas Basin, Gulf of California. Cell aggregates covering the surface of sulfide-emanating sediments and rock chimne...
Colonial aggregation among nonheterocystous filaments of the planktonic marine cyanobacterium Trichodesmium is known to enhance N(2) fixation, mediated by the O(2)-sensitive enzyme complex nitrogenase. Expression of nitrogenase appears linked to the formation of O(2)-depleted microzones within aggregated bacterium-asso...
A Bradyrhizobium sp. (Lotus) strain that formed a soil population that was highly competitive for nodulation of Lotus pedunculatus 11 years after its introduction into a field soil and a culture of the same strain stored lyophilized were compared with an antibiotic-resistant mutant in respect of their nodulation compet...
Cultures enriched by serial transfer through a mineral salts medium containing fluoranthene were used to establish a stable, seven-member bacterial community from a sandy soil highly contaminated with coal tar creosote. This community exhibited an ability to utilize fluoranthene as the sole carbon source for growth, as...
The procedure generally used for the isolation of extracellular, cell-associated proteinases of Lactococcus lactis species is based on the release of the proteinases by repeated incubation and washing of the cells in a Ca-free buffer. For L. lactis subsp. cremoris Wg2, as many as five incubations for 30 min at 29 degre...
Arthrobacter protophormiae produced a high level of extracellular endo-beta-N-acetylglucosaminidase when cells were grown in a medium containing ovalbumin. The enzyme was induced by the glycopeptide fraction of ovalbumin prepared by pronase digestion. Production of the enzyme was also induced by glycoproteins such as y...
Fermentation of dilute-acid-pretreated mixed hardwood and Avicel by Clostridium thermocellum was compared in batch and continuous cultures. Maximum specific growth rates per hour obtained on cellulosic substrates were 0.1 in batch culture and >0.13 in continuous culture. Cell yields (grams of cells per gram of substrat...
An alpha-amylase gene (AMY) was cloned from Schwanniomyces occidentalis CCRC 21164 into Saccharomyces cerevisiae AH22 by inserting Sau3AI-generated DNA fragments into the BamHI site of YEp16. The 5-kilobase insert was shown to direct the synthesis of alpha-amylase. After subclones containing various lengths of restrict...
A simple and rapid method was developed to detect beta-galactosidase by using alpha- or beta-naphthyl-beta-d-galactopyranoside as substrate and fast garnet GBC as a dye coupler following polyacrylamide gel electrophoresis. This method was specific for beta-galactosidase but not for phospho-beta-galactosidase.
A sand column adhesion assay was developed which distinguishes the adhesion abilities of a number of pseudomonads isolated from fine sandy loam. Pseudomonas fluorescens Pf0-1 which adhered at >90% of the total cells added was subjected to transposon Tn5 insertion mutagenesis. From 2,500 Pf0-1::Tn5 mutants examined in t...
Glucose and xylulose fermentation and product formation by Saccharomyces cerevisiae were compared in batch culture under anaerobic conditions. In both cases the main product was ethanol, with glycerol, xylitol, and arabitol produced as by-products. During glucose and xylulose fermentation, 0.74 and 0.37 g of cell mass ...
Cells of the anaerobic ruminal bacterium Fibrobacter succinogenes subsp. succinogenes S85 (formerly Bacteroides succinogenes) exhibit arylesterase activity. When cells were grown on cellulose, it was found that 69% of the total esterase activity was extracellular while 65% was nonsedimentable upon centrifugation of the...
A strain of Pseudomonas syringae was recently identified as the cause of a new foliar blight of impatiens. The bacterium was resistant to copper compounds, which are used on a variety of crops for bacterial and fungal disease control. The bacterium contained a single 47-kilobase plasmid (pPSI1) that showed homology to ...
Large-scale composting facilities are known to cause environmental problems, mainly through pungent air emitted by composting material. In air samples taken above stacks set up to prepare compost used as a substrate in mushroom cultivation, several volatile compounds were identified by means of the coupled techniques o...
A combination of plasmid curing and DNA-DNA hybridization data facilitated the identification of proteinase plasmids of 75 (pCI301) and 35 kilobases (pCI203) in the multi-plasmid-containing strains Lactococcus lactis subsp. lactis UC317 and L. lactis subsp. cremoris UC205, respectively. Both plasmids were transferred b...
Exoprotease activity during 120 h of total energy and nutrient starvation was examined in two marine bacteria, Vibrio sp. strain S14 and Pseudomonas sp. strain S9. The activity was determined by spectrophotometric measurement of the rate of release of soluble color from an insoluble azure dye derivative of hide powder ...
Two families of peroxidases-lignin peroxidase (LiP) and manganese-dependent lignin peroxidase (MnP)-are formed by the lignin-degrading white rot basidiomycete Phanerochaete chrysosporium and other white rot fungi. Isoenzymes of these enzyme families carry out reactions important to the biodegradation of lignin. This re...
Radiolabeled phytoplankton and macrophyte lignocelluloses were incubated at pHs 4 and 7 in water from a naturally acidic freshwater wetland (Okefenokee Swamp; ambient pH, 3.8 to 4.2), a freshwater reservoir (L-Lake; pH 6.7 to 7.2), and a marine marsh (Sapelo Island; pH approximately 7.8). The data suggest that acidity ...
In bakers' yeast, an immediate alcoholic fermentation begins when a glucose pulse is added to glucose-limited, aerobically grown cells. The mechanism of this short-term Crabtree effect was investigated via a comparative enzymic analysis of eight yeast species. It was established that the fermentation rate of the organi...
Radiocarbon incorporation from pyruvate and serine into monomethylmercury by Desulfovibrio desulfuricans was consistent with the proposal that the methyl group originates from C-3 of serine. Immunodiagnostic assays measured 4 to 35 mug of tetrahydrofolate and 58 to 161 ng of cobalamin or a closely related cobalt porphy...
The effects of 3,5-dichlorophenol, 2,4-dinitrophenol, and potassium dichromate on natural bacterial assemblages were examined by means of [H]thymidine incorporation into trichloroacetic acid-insoluble material. Results from a large number of coastal marine and freshwater samples suggest the following. (i) The effects o...
X-prolyl-dipeptidyl aminopeptidase, which hydrolyzed Gly-Pro-p-nitroanilide (relative activity [RA] = 100%) and Arg-Pro-p-nitroanilide (RA, 130%), was purified to homogeneity from the cell extract of Lactobacillus helveticus CNRZ 32. The enzyme also hydrolyzed Ala-Pro-Gly (RA, 11%) and Ala-Ala-p-nitroanilide (RA, 2%) b...
Copper-resistant strains of Xanthomonas campestris pv. vesicatoria, Pseudomonas cichorii, Pseudomonas putida, Pseudomonas fluorescens, and a yellow Pseudomonas sp. were isolated from tomato plants or seeds. In Southern hybridizations, DNA from each strain showed homology with the copper resistance (cop) operon previous...
The stability of identification markers was examined for two Rhizobium galegae inoculant strains after 5 years in the field. The two strains are genetically closely related, but differ in their lipopolysaccharides. Strain HAMBI 540 has lipopolysaccharide of the rough type, whereas that of strain HAMBI 1461 is of the sm...
Three experiments were performed to determine the effect of selected saccharides on mushroom yield and basidiome size of shiitake (Lentinula edodes) when grown on a synthetic substrate. Substrate formulations of sawdust, wheat bran, and millet were nonamended or amended with sucrose, fructose, or glucose. Addition of s...
Rhizobium meliloti, like many other bacteria, accumulates high levels of glutamic acid when osmotically stressed. The effect was found to be proportional to the osmolarity of the growth medium. NaCl, KCI, sucrose, and polyethylene glycol elicited this response. The intracellular levels of glutamate and K began to incre...
An aminopeptidase was purified to homogeneity from a crude cell extract of Lactococcus lactis subsp. cremoris Wg2 by a procedure that included diethyl-aminoethane-Sephacel chromatography, phenyl-Sepharose chromatography, gel filtration, and high-performance liquid chromatography over an anion-exchange column. Sodium do...
Chemolithoautotrophic bacteria were enriched from mine water at incubation temperatures ranging from 4 to 46 degrees C, using elemental sulfur as a substrate in acid mineral salts media. Thiobacillus-type bacteria were successfully enriched for at all test temperatures except 46 degrees C. Changes in pH (-dpH/dt) were ...
Inhibition of the fermentation of propionate to methane and carbon dioxide by hydrogen, acetate, and propionate was analyzed with a mesophilic propionate-acclimatized sludge that consisted of numerous flocs (size, 150 to 300 mum). The acclimatized sludge could convert propionate to methane and carbon dioxide stoichiome...
Two truncated Bacillus thuringiensis crystal protein genes, belonging to the classes cryIA(b) and cryIC and both coding for insecticidal N-terminal fragments of the corresponding crystal proteins, were translationally fused. Expression of the gene fusion in Escherichia coli showed a biologically active protein with a t...
Hebeloma crustuliniforme produced an extracellular acid proteinase in a liquid medium containing bovine serum albumin as the sole nitrogen source. The proteinase was purified 26-fold with 20% activity recovery and was shown to have a molecular weight of 37,800 (as indicated by sodium dodecyl sulfate-polyacrylamide gel ...
Bacillus megaterium P1, a bacterial strain capable of hydrolyzing chitosan, was isolated from soil samples. Chitosan-degrading activity was induced by chitosan but not by its constituent d-glucosamine. Extracellular secretion of chitosanase reached levels corresponding to 1 U/ml under optimal conditions. Three chitosan...
F(420)-nonreactive and F(420)-reactive hydrogenases have been partially purified from Methanococcus jannaschii, an extremely thermophilic methanogen isolated from a submarine hydrothermal vent. The molecular weights of both hydrogenases were determined by native gradient electrophoresis in 5 to 27% polyacrylamide gels....
Cells of the amylolytic bacterium KB-1 (thought to be an Arthrobacter sp.) adhered ( approximately 70%) to the surface of plastic films composed of starch-poly (methylacrylate) graft copolymer (starch-PMA), but did not adhere (<10%) to films composed of polymethylacrylate (PMA), polyethylene (PE), carboxymethyl cellulo...
A thermoanaerobe (Thermoanaerobacter sp.) grown in TYE-starch (0.5%) medium at 60 degrees C produced both extra- and intracellular pullulanase (1.90 U/ml) and amylase (1.19 U/ml) activities. Both activities were produced at high levels on a variety of carbon sources. The temperature and pH optima for both pullulanase a...
Batch tests to measure maximum acetate utilization rates were used to determine the distribution of acetate utilizers in expanded-bed sand and expanded-bed granular activated carbon (GAC) reactors. The reactors were fed a mixture of acetate and 3-ethylphenol, and they contained the same predominant aceticlastic methano...
Lactobacillus reuteri utilizes exogenously added glycerol as a hydrogen acceptor during carbohydrate fermentations, resulting in higher growth rates and cell yields than those obtained during growth on carbohydrates alone. Glycerol is first converted to 3-hydroxypropionaldehyde by a coenzyme B(12)-dependent glycerol de...
The incorporation of tritiated thymidine by five microbial ecosystems and the distribution of tritium into DNA, RNA, and protein were determined. All microbial assemblages tested exhibited significant labeling of RNA and protein (i.e., nonspecific labeling), as determined by differential acid-base hydrolysis. Nonspecif...
A study was conducted to determine the activity of the 3-methylindole (3MI)-forming enzyme in Lactobacillus sp. strain 11201. Cells were incubated anaerobically with 17 different indolic and aromatic compounds. Indoleacetic acid (IAA), 5-hydroxyindoleacetic acid, 5-methoxy-3-indoleacetic acid, indole-3-pyruvate, or ind...
As part of an interdisciplinary study of hydrothermal vents on the Endeavour Segment of the Juan de Fuca Ridge, we used the submersible ALVIN to collect 57 fluid samples in titanium syringes and Go Flo Niskin bottles from 17 different hot vents (smokers and flanges) and their environs for the purpose of extracting part...
The octopine-utilizing strain Agrobacterium tumefaciens B6S3 and three nonagrobacteria which had the capacity to utilize this opine were compared for octopine uptake. The characteristics of uptake by Rhizobium meliloti A3 and strain B6S3 were similar. In both bacteria, uptake activity was inducible by octopine and by t...
An improved method for the isolation of the biosurfactant glycolipids from Rhodococcus sp. strain H13A by using XM 50 diafiltration and isopropanol precipitation was devised. This procedure was advantageous since it removes protein coisolated when the glycolipids are obtained by organic extraction and silicic acid chro...
A feather-degrading culture was enriched with isolates from a poultry waste digestor and adapted to grow with feathers as its primary source of carbon, sulfur, and energy. Subsequently, a feather-hydrolytic, endospore-forming, motile, rod-shaped bacterium was isolated from the feather-degrading culture. The organism wa...
A method capable of detecting as little as 0.11 U of xylanase activity in polyacrylamide gels was developed. The method entails incubation of protein gels in contact with substrate gels containing unmodified xylan, followed by immersion of substrate gels in 95% ethanol. Resulting zymograms contain transparent bands cor...
Rates of degradation of radiolabeled hydrocarbons and incidence of bacterial plasmid DNA were investigated in sediment samples collected from the Campeche Bank, Gulf of Mexico, site of an offshore oil field containing several petroleum platforms. Overall rates of mineralization of [C]hexadecane and [C]phenanthrene meas...
Two 2,3-butanediol dehydrogenases (enzymes 1 and 2; molecular weight of each, 170,000) have been partially purified from Lactococcus lactis subsp. lactis (Streptococcus diacetylactis) D10 and shown to have reductase activity with either diacetyl or acetoin as the substrate. However, the reductase activity with 10 mM di...
Experimental bioreactors operated as recirculated closed systems were inoculated with bacterial cultures that utilized methane, propane, and tryptone-yeast extract as aerobic carbon and energy sources and degraded trichloroethylene (TCE). Up to 95% removal of TCE was observed after 5 days of incubation. Uninoculated bi...
In this paper, plans are given for the construction of an inexpensive enzyme-linked immunosorbent assay plate washer from readily available materials. The wash unit uses an intermittent wash cycle based on a wash manifold cycling over the microdilution plates for a predetermined time. Laboratory tests showed that the u...
The herbicide 2,4,5-trichlorophenoxyacetic acid (2,4,5-T) was dehalogenated in samples from a methanogenic aquifer to form 2,4- and 2,5-dichlorophenoxyacetic acids as the first detected intermediates. Further incubation of the aquifer slurries resulted in the formation of several intermediates including monochloropheno...
A tripeptidase from a cell extract of Lactococcus lactis subsp. cremoris Wg2 has been purified to homogeneity by DEAE-Sephacel and phenyl-Sepharose chromatography followed by gel filtration over a Sephadex G-100 SF column and a high-performance liquid chromatography TSK G3000 SW column. The enzyme appears to be a dimer...
The catechol 1,2-dioxygenase of Rhizobium leguminosarum biovar viceae USDA 2370 was purified 296-fold, yielding a homogeneous preparation with a specific activity of 51.1 U mg of protein. The molecular weight of the native protein was 70,000, with two identical subunits of 34,500 and 1 g-atom of iron per mol. The optim...
The hyperthermophilic archaebacterium Pyrococcus furiosus produces several amylolytic enzymes in response to the presence of complex carbohydrates in the growth medium. These enzyme activities, alpha-glucosidase, pullulanase, and alpha-amylase, were detected in both cell extracts and culture supernatants. All activitie...
Lactobacillus delbrueckii subsp. bulgaricus CNRZ 397 is able to hydrolyze X-proline-para-nitroanilides and X-proline-beta-naphthylamides (X for alanyl- or glycyl-). A single metal-independent cytoplasmic enzyme with a molecular weight estimated to be 82,000 is responsible for these activities and was named X-prolyl-dip...
A plate assay to detect the presence of alginate lyases (EC 4.2.2.3) has been developed. The simultaneous use of specific alginate block structures of defined composition allows the substrate specificity of the enzymes to be determined. Clearing zones in the alginate-containing media are visualized with either cetyl py...
The effects of different organic substrates on the abilities of anaerobic sediment enrichments to reductively dechlorinate polychlorinated biphenyls (PCBs) were studied. Sediments collected from a site previously contaminated with PCBs were dosed with additional PCBs (Aroclor 1242; approximately 300 ppm [300 mug/g], se...
When di-, tri-, and tetrachloroaniline were incubated in methanogenic groundwater slurries, they were reductively dehalogenated by the aquifer microbiota. 2,3,4-Trichloroaniline was metabolized by two pathways. Primary dehalogenation occurred at either the meta or ortho position of this substrate to form 2,4- and 3,4-d...
CitrLactococcus lactis subsp. lactis 3022 produced more biomass and converted most of the glucose substrate to diacetyl and acetoin when grown aerobically with hemin and Cu. The activity of diacetyl synthase was greatly stimulated by the addition of hemin or Cu, and the activity of NAD-dependent diacetyl reductase was ...
Adhesion of the cellulolytic ruminal bacteria Ruminococcus flavefaciens and Fibrobacter succinogenes to barley straw was measured by incubating bacterial suspensions with hammer-milled straw for 30 min, filtering the mixtures through sintered glass filters, and measuring the optical densities of the filtrates. Maximum ...
The host range of a multiply enveloped nuclear polyhedrosis virus (NPV) (Baculoviridae) isolated from the cabbage moth, Mamestra brassicae (Lepidoptera: Noctuidae), was determined by challenging a wide range of insect species with high (10 polyhedral inclusion bodies) and low (10 polyhedral inclusion bodies) doses of t...
Several wild-type isolates of marine bdellovibrios formed stable bdelloplasts when they infected gram-negative bacterial prey under certain culture conditions. Synchronous predator-prey cultures and low nutrient concentrations increased the yield of stable bdelloplasts. The bdellovibrio cells retained in the stable bde...
In order to influence the fermentation pattern of Propionibacterium freudenreichii towards enhanced propionate formation, growth and product formation with glucose and lactate as energy sources were studied in a three-electrode poised-potential amperometric culture system. With anthraquinone 2,6-disulfonic acid (E(0)' ...
Baculoviruses are insect pathogens with a relatively slow speed of action, and this has limited their use as control agents of insect pests. Introduction into baculoviruses of genes which code for proteins interfering specifically with insect metabolism or metamorphosis, such as toxins, hormones, and enzymes, may enhan...
A rapid and sensitive spectrophotometric procedure was developed for monitoring the growth of Thiobacillus ferrooxidans in liquid culture. Values determined for the optical densities at 500 nm of washed T. ferrooxidans cell suspensions were directly proportional to both total cell number and total cell protein concentr...
The growth characteristics of five octopine-catabolizing pseudomonads have been determined in batch and continuous cultures. All five strains belonged to rRNA homology group I and showed a more psychrotrophic growth pattern than did Agrobacterium tumefaciens B6 and ATCC 15955. In chemostats limited by octopine, either ...
We studied the transformation of halogenated benzoates by cell extracts of a dehalogenating anaerobe, "Desulfomonile tiedjei." We found that cell extracts possessed aryl reductive dehalogenation activity. The activity was heat labile and dependent on the addition of reduced methyl viologen, but not on that of reduced N...
Actinomycetes grown on wheat straw solubilized a lignocarbohydrate fraction which could be recovered by acid precipitation. Further characterization of this product (APPL) during growth of Streptomyces sp. strain EC1 revealed an increase in carboxylic acid and phenolic hydroxyl content, suggesting progressive modificat...
The production of a suitable substrate for the cultivation of the common white button mushroom, Agaricus bisporus, is referred to as composting. High microbiological activity causes temperatures of the composting material to rise as high as 80 degrees C. At stacking, an optimal oxygen consumption rate of 140 mumol of O...
Differences in the digestion of barley, maize, and wheat by three major ruminal starch-digesting bacterial species, Streptococcus bovis 26, Ruminobacter amylophilus 50, and Butyrivibrio fibrisolvens A38, were characterized. The rate of starch digestion in all cereal species was greater for S. bovis 26 than for R. amylo...