Publications

fine structure of methanospirillum hungatii.	the fine structure of methanospirillum hungatii was studied by electron microscopy. the topography of the cell wall and the mechanism of cell division are not typical of gram-positive or gram-negative bacteria. a novel architectural arrangement of cells in continuous spiral filaments is described. filamentous cells are connected by spacers and enclosed within a rigid outer envelope. the unique ultrastructural features of cells and cell spacers were examined.	1975	46863
new method for the isolation and identification of methanogenic bacteria.	a new technique is reported for the rapid growth and detection of methanogenic bacteria by using petri plates. the method employs an anaerobic glove box containing an inner chamber with separate gas-flushing facilities. the numbers of methanogenic bacteria recovered from domestic sewage sludge are comparable to those recovered by other methods. the methanogenic organisms isolated from sludge include methanosarcina, methanospirillum, methanobacterium strain m.o.h., and methanobacterium formicicum ...	1975	804855
temperature limitation of methanogenesis in aquatic sediments.	microbial methanogenesis was examined in sediments collected from lake mendota, wisconsin, at water depths of 5, 10, and 18 m. the rate of sediment methanogenesis was shown to vary with respect to sediment site and depth, sampling date, in situ temperature, and number of methanogens. increased numbers of methanogenic bacteria and rates of methanogenesis correlated with increased sediment temperature during seasonal change. the greatest methanogenic activity was observed for 18-m sediments throug ...	1976	821396
characterization of a strain of methanospirillum hungatti.	the results of morphological, base ratio, nutritional, temperature, and ph studies on a strain of methanospirillum hungatii, isolated from an anaerobic pear waste digester, are described. the isolate, designated as strain gp 1, was compared with some of the characteristics of type-strain m. hungatii jf 1. strain gp 1 is gram-negative, weakly motile, and a strict anaerobe with a guanine plus cytosine (g +c) content of 46.5 mol%. the preferred substrates for methane production are hydrogen, carbon ...	1976	10074
effect of sodium chloride on growth and methane production of methanogens.	the effect of up to 263.7 mm sodium chloride on the growth and methane production by pure cultures of methanospirillum hungatii gp1, methanobacterium moh, methanobacterium thermoautotrophicum, and an unidentified methanogen was studied. growth and methane production by m. hungatii gp1 were not affected up to 97.3 mm nacl but there was some inhibition of growth at higher concentrations. growth of methanobacterium moh was independent of sodium chloride concentration within the range investigated. ...	1977	884626
nutritional and biochemical characterization of methanospirillum hungatii.	to ascertain its physiological similarity to other methanogenic bacteria, methanospirillum hungatii, the type species of the genus, was characterized nutritionally and biochemically. good growth occurred in a medium consisting of mineral salts, cysteine sulfide reducing buffer, and an h2-co2 (80:20) atmosphere. addition of amino acids and b vitamins stimulated growth. cell-free extracts contained methylcobalamin-coenzyme m methyltransferase, methylreductase, and formate hydrogenlyase. cells cont ...	1977	411420
acetic acid and hydrogen metabolism during coculture of an acetic acid producing bacterium with methanogenic bacteria.	two microorganisms originally existing as a mixed culture obtained from an anaerobic digester fluid were separated for pure and coculture studies. one of these was motile, gram-negative, and non-sporeforming, and it required yeast extract for growth and acetic acid production. this isolate produced h2 and did not need h2 and (or) co2 for growth and acetate formation. the other isolate was a methanogen whick resembled methanobacterium arbophilicum in morphology and substrate specificity. cocultur ...	1978	688097
chemical composition of the peptidoglycan-free cell walls of methanogenic bacteria.	cell walls were prepared from freeze-dried samples of 7 strains of methanobacterium by mechanical disintegration of the cells followed by incubation with trypsin. electron microscopy revealed the presence of sacculi exhibiting the shape of the original cells, on which no surface structure could be detected. ultrathin sections of the isolated sacculi showed a homogenously electron dense layer of about 10--15 nm in width. the ash content varied between 8 and 18% of dry weight. the sacculi of all t ...	1978	697504
diphytanyl and dibiphytanyl glycerol ether lipids of methanogenic archaebacteria.	the lipids of nine different methanogenic bacterial strains are comprised of diphytanyl glycerol diethers, previously known only in extremely halophilic bacterial, as well as dibiphytanyl diglycerol tetraethers, known formerly only in the extremely thermoacidophilic bacteria thermoplasma and sulfolobus. of the methanogens examined from four representative taxonomic groups, methanobacterium and methanospirillum contained both types of isopranyl ethers in nearly equal proportions, whereas the cocc ...	1979	758677
methane formation and methane oxidation by methanogenic bacteria.	methanogenic bacteria were found to form and oxidize methane at the same time. as compared to the quantity of methane formed, the amount of methane simultaneously oxidized varied between 0.3 and 0.001%, depending on the strain used. all the nine tested strains of methane producers (methanobacterium ruminantium, methanobacterium strain m.o.h., m. formicicum, m. thermoautotrophicum, m. arbophilicum, methanobacterium strain az, methanosarcina barkeri, methanospirillum hungatii, and the "acetate org ...	1979	762019
squalenes, phytanes and other isoprenoids as major neutral lipids of methanogenic and thermoacidophilic "archaebacteria".	the neutral lipids of nine species of methanogenic bacteria including five methanobacilli, two methanococci, a methanospirillum, one methanosarcina as well as two thermoacidophilic bacteria, thermoplasma and sulfolobus, were analyzed. the major components were c30, c25 and/or c20 acylic isoprenoid hydrocarbons with a continuous range of hydroisoprenoid homologues. the range of acyclic isoprenoids detected were from c14 to c30. apart from methanosarcina barkeri, squalene and/or hydrosqualene deri ...	1979	458874
intestinal microbial flora of the of the american cockroach, periplaneta americana l.	a morphological study employing scanning and transmission electron microscopy was made by the alimentary tract of the american cockroach, periplaneta americana l. a. complex microbiota of diverse morphology, which could not be readily dislodged, was observed and found to be restricted to the hindgut, particularly the colon. numerous filamentous forms were noted, and some are described, including the morphologically distinct methanospirillum. flora was noted attached to the cuticular lining and c ...	1979	543705
properties of malate dehydrogenase isolated from methanospirillum hungatii.	a nadh-linked oxygen-tolerant malate dehydrogenase was purified 270-fold from cell extracts of methanospirillum hungatii. inhibitors of the enzyme included adp, alpha-ketoglutarate, and excess nadh. inhibition patterns for adp were competitive with respect to nadh and non-competitive with respect to oxalacetate. inhibition by alpha-ketoglutarate was non-competitive with oxalacetate as variable substrate and uncompetitive with respect to nadh. alpha-ketoglutarate is surmised to function as an end ...	1979	35274
spheroplasts of methanospirillum hungatii formed upon treatment with dithiothreitol.		1979	38895
composition of methanospirillum hungatii gp1 during growth on different media.	growth of methanospirillum hungatii gp1 as determined by optical density measurement wsa comparable to growth assessed by cell dry weight, ribonucleic acid content, and deoxyribonucleic acid content. cultivation of m. hungatii on synthetic medium containing mineral salts, vitamins, and acetic acid indicated that, on a dry weight basis, cell constituents such as protein (71%), ribonucleic acid (15.8%), deoxyribonucleic acid (1.6%), and total carbohydrate (3.2%) did not vary significantly with the ...	1980	6156749
viability and depletion of cell constituents of methanospirillum hungatii gp1 during starvation.	the viability of methanospirillum hungatii gp1 cells dropped rapidly when starved in a ph 7.0 phosphate buffer under 100% n2 or 90% n2 - 10% h2 gas phase. the presence of h2 during starvation tests resulted in a more rapid and an ultimately greater reduction of the number of initially viable cells than in the presence of n2 only. the decrease in viability was observed concurrently with the decline of the atp pool and the rna content of the cells. the cell protein, carbohydrate, and amino acid po ...	1980	6161686
characterization of an acetate-decarboxylating, non-hydrogen-oxidizing methane bacterium.	a methanogenic bacterium, commonly seen in digested sludge and referred to as the "fat rod" or methanobacterium soehngenii, has been enriched to a monoculture and is characterized. cells are gramnegative, non-motile and appear as straight rods with flat ends. they form filaments which can grow to great lengths. the structure of the outer cell envelop is similar to methanospirillum hungatii. the organism grows on a mineral salt medium with acetate as the only organic component. acetate is the ene ...	1980	6769415
composition and properties of the cell wall of methanospirillum hungatii.	dithiothreitol reacted, at ph 9.0, with the isolated cell walls of methanospirillum hungatii, to release about 23% of the cell wall dry weight as a high molecular weight fraction (> 0.5 million daltons). untreated walls consisted of 70% amino acids, 11% lipid, and 6.6% carbohydrate. sugars were identified as rhamnose, ribose, glucose, galactose, and mannose. the wall material that was released contained only 47% amino acids and was enriched in lipid, glucose, and phosphate. these results support ...	1980	7407700
sediment distribution of methanogenic bacteria in lake erie and cleveland harbor.	the direct fluorescent-antibody technique was employed to determine the distribution patterns of four species of methanogens in the sediments of lake erie and cleveland harbor. methanobacterium ruminantium was the most numerous methanogen found in regions of high-organic-silt sediments. the population of this species ranged from 10 to 10 cells/g of dry sediment. methanobacterium strain moh and methanosarcina barkeri were identified in sand-silt, clay, or sand sediments. these methanogens ranged ...	1980	16345529
propionate-degrading bacterium, syntrophobacter wolinii sp. nov. gen. nov., from methanogenic ecosystems.	a new genus and species of a nonmotile gram-negative rod, syntrophobacter wolinii, is the first bacterium described which degrades propionate only in coculture with an h(2)-using organism and in the absence of light or exogenous electron acceptors such as o(2), sulfate, or nitrate. it was isolated from methanogenic enrichments from an anaerobic municipal sewage digestor, using anaerobic roll tubes containing a medium with propionate as the energy source in association with an h(2)-using, sulfate ...	1980	16345640
syntrophomonas wolfei gen. nov. sp. nov., an anaerobic, syntrophic, fatty acid-oxidizing bacterium.	an anaerobic, nonphototrophic bacterium that beta-oxidizes saturated fatty acids (butyrate through octanoate) to acetate or acetate and propionate using protons as the electron acceptor (h(2) as electron sink product) was isolated in coculture with either a non-fatty acid-degrading, h(2)-utilizing desulfovibrio sp. or methanogens. three strains of the bacterium were characterized and are described as a new genus and species, syntrophomonas wolfei. s. wolfei is a gram-negative, slightly helical r ...	1981	16345745
novel complex polar lipids from the methanogenic archaebacterium methanospirillum hungatei.	the methanogenic archaebacterium methanospirillum hungatei contains two unusual phosphoglycolipids that account for 64 percent of the total cellular lipids. these lipids are derivatives of the dibiphytanyl diglycerol tetraether, previously identified in methanogens. one of the free hydroxyls of this tetraether is esterified with glycerophosphoric acid, and the other is linked glycosidically to a disaccharide. the two phosphoglycolipids may function as covalently bonded lipid bilayers to impart s ...	1981	7466385
syntrophic association of a butyrate-degrading bacterium and methanosarcina enriched from bovine rumen fluid.	an anaerobic butyrate-degrading bacterium, morphologically similar to syntrophomonas wolfei, was isolated in coculture with desulfovibrio strain g11 from an enrichment of bovine rumen fluid. a methanosarcina species was the major h2-using organism in the enrichment. the results are discussed in relationship to the absence of methanospirillum hungatei, the h2-using methanogen usually found in association with s. wolfei, and the finding of methanosarcina rather than methanobrevibacter ruminantium ...	1981	7224635
novel polar lipids from the methanogen methanospirillum hungatei gp1.	the methanogenic bacterium methanospirillum hungatei gp1 has been shown to contain two unusual phosphoglycolipids (phosphoglycolipid i and phosphoglycolipid ii) that account for 64% (by wt.) of the total cellular lipids. these lipids are derivatives of the dibiphytanyldiglycerol tetraether. one of the free hydroxyls of this tetraether is esterified with glycerophosphoric acid and the other is linked glycosidically to a disaccharide with structure alpha-glcp-(1 leads to 2)-beta gal phi in phospho ...	1981	7236696
k+, na+, and mg2+ content and permeability of methanospirillum hungatei and methanobacterium thermoautotrophicum.	the k+, na+, and mg2+ contents of methanospirillum hungatei and of the thermophile methanobacterium thermoautotrophicum were determined at various phases of growth. the intracellular k+ content of exponential phase cells of m. thermoautotrophicum (approximately 780 mm) was 5.4-fold higher than in m. hungatei, and decreased gradually as the culture entered the stationary phase. both methanogens concentrated mg2+, exhibiting an increased content as the cultures aged. comparisons among extraction m ...	1981	7237289
the transmembrane electrical potential and intracellular ph in methanogenic bacteria.	the magnitudes of the electrical potential and proton gradient in methanospirillum hungatei gp1 and methanobacterium thermoautotrophicum were determined. no delta ph (inside alkaline) could be demonstrated in either organism suspended in growth media at normal growth ph values by the distribution of 5,5-dimethyl-2,4-oxazolidinedione (dmo), butyrate, propionate, or methylamine. the internal ph, estimated to be approximately 6.7 under our growth conditions, was not constant, but varied as the exte ...	1981	7296406
kinetic and physical properties of the l-malate-nad+ oxidoreductase from methanospirillum hungatii and comparison with the enzyme from other sources.	the l-malate-nad+ oxidoreductase of methanospirillum hungatii was purified to homogeneity by using blue sepharose and adp-sepharose affinity chromatography. the molecular weight was estimated as 61 700 +/- 1900 by gel filtration and 64 200 +/- 1200 by ultracentrifugation. sodium dodecyl sulphate/polyacrylamide-gel electrophoresis indicated that the protein is composed of two polypeptide chains, each corresponding to 31 350 +/- 2150 daltons. inhibition patterns obtained for malate, alpha-oxogluta ...	1981	7305925
isolation and characterization of a fad-dependent nadh diaphorase from methanospirillum hungatei strain gp1.	crude extracts of methanospirillum hungatei strain gp1 contained nadh and nadph diaphorase activities. after a 483-fold purification of the nadh diaphorase the enzyme was further separated from contaminating proteins by polyacrylamide disc gel electrophoresis. two distinct activity bands were extracted from the acrylamide, each one having oxygen, 2,6-dichlorophenolindophenol, and cytochrome c linked activities. in these preparations nadph could not replace nadh as electron donor. during the init ...	1981	6263428
coupling of methyl coenzyme m reduction with carbon dioxide activation in extracts of methanobacterium thermoautotrophicum.	the stimulation of carbon dioxide reduction to methane by addition of 2-(methylthio)ethanesulfonate (ch3-s-com) to cell extracts of methanobacterium thermoautotrophicum was investigated. similar stimulation of co2 reduction by ch3-s-com was found for cell extracts of methanobacterium bryantii and methanospirillum hungatei. the ch3-s-com requirement could be met by the methanogenic precursors formaldehyde, serine, or pyruvate, or by 2-(ethylthio)ethanesulfonate (ch3ch2-s-com), but not by other co ...	1982	6813316
sensitivity of methanogenic bacteria to dicyclohexylcarbodiimide.	methanospirillum hungatei strains gp1 and jf1 when exposed to the adenosinetriphosphatase inhibitor n,n'-dicyclohexylcarbodiimide experienced a marked decline in growth rates, methane synthesis activities, and intracellular atp concentrations. although growth was inhibited, the intracellular atp concentrations of all other methanogens tested were little affected by high concentrations of dicyclohexylcarbodiimide (500 microm). thus, for studies of atp synthesis, or for atp depletion in whole cell ...	1982	7139410
kinetics of formate metabolism in methanobacterium formicicum and methanospirillum hungatei.	the kinetics of formate metabolism in methanobacterium formicicum and methanospirillum hungatei were studied with log-phase formate-grown cultures. the progress of formate degradation was followed by the formyltetrahydrofolate synthetase assay for formate and fitted to the integrated form of the michaelis-menten equation. the k(m) and v(max) values for methanobacterium formicicum were 0.58 mm formate and 0.037 mol of formate h g (dry weight), respectively. the lowest concentration of formate met ...	1982	16346087
biosynthetic pathways in methanospirillum hungatei as determined by 13c nuclear magnetic resonance.	the main metabolic pathways in methanospirillum hungatei gp1 were followed by using 13c nuclear magnetic resonance, with 13c-labeled acetate and co2 as carbon sources. the labeling patterns found in carbohydrates, amino acids, lipids, and nucleosides were consistent with the formation of pyruvate from acetate and co2 as the first step in biosynthesis. carbohydrates are formed by the glucogenic pathway, and no scrambling of label was observed, indicating that the oxidative or reductive pentose ph ...	1983	6619097
isolation and chemical composition of the cytoplasmic membrane of the archaebacterium methanospirillum hungatei.	the cytoplasmic membrane of methanospirillum hungatei was isolated from osmotic lysates of spheroplasts, with yields of 7-8% of the cell dry weight. cytoplasmic contamination was negligible, as judged by the removal of soluble enzymes. the cytoplasmic membrane consists of lipid (35-37%), primarily as a biphytanyldiglycerol tetraether glycolipid; protein (45-50%); and carbohydrate (10-12%). ultra-thin sections showed that the trilaminar membrane formed vesicles with a maximum diameter of 0.4 micr ...	1983	6833242
fermentative degradation of polyethylene glycol by a strictly anaerobic, gram-negative, nonsporeforming bacterium, pelobacter venetianus sp. nov.	the synthetic polyether polyethylene glycol (peg) with a molecular weight of 20,000 was anaerobically degraded in enrichment cultures inoculated with mud of limnic and marine origins. three strains (gra peg 1, gra peg 2, and ko peg 2) of rod-shaped, gram-negative, nonsporeforming, strictly anaerobic bacteria were isolated in mineral medium with peg as the sole source of carbon and energy. all strains degraded dimers, oligomers, and polymers of peg up to a molecular weight of 20,000 completely by ...	1983	6881964
ammonia/potassium exchange in methanogenic bacteria.	methanospirillum hungatei exposed to ammonia in a k+-free buffer lost up to 98% of the cytoplasmic k+ through an ammonia/k+ exchange reaction. the exchange was immediate, and occurred in cells poisoned by air or by other metabolic inhibitors. additions of nh4oh or various nh+4 salts (or methylamine) were most effective in causing k+ depletion in media of alkaline ph, suggesting that nh3 was the chemical species crossing the membrane. in alkaline media, the exchange reaction resulted in a dissipa ...	1984	6490632
isolation and partial characterization of bacteria in an anaerobic consortium that mineralizes 3-chlorobenzoic acid.	a methanogenic consortium able to use 3-chlorobenzoic acid as its sole energy and carbon source was enriched from anaerobic sewage sludge. seven bacteria were isolated from the consortium in mono- or coculture. they included: one dechlorinating bacterium (strain dcb-1), one benzoate-oxidizing bacterium (strain bz-2), two butyrate-oxidizing bacteria (strains sf-1 and nsf-2), two h(2)-consuming methanogens (methanospirillum hungatei pm-1 and methanobacterium sp. strain pm-2), and a sulfate-reducin ...	1984	16346648
nutrition and growth characteristics of trichomitopsis termopsidis, a cellulolytic protozoan from termites.	putatively axenic cultures of trichomitopsis termopsidis 6057, isolated by m. a. yamin (j. protozool. 25:535-538, 1978) from the hindgut of zootermopsis termites, apparently contained methanogenic bacteria, inasmuch as small amounts of ch(4) were produced during growth. however, t. termopsidis could be "cured" of methanogenic activity by incubation in the presence of bromoethanesulfonate. both the cured derivative (6057c) and the parent strain (6057) required nahco(3) and fetal bovine serum for ...	1985	16346754
influence of calcium addition on growth of highly purified syntrophic cultures degrading long-chain fatty acids.	two highly purified syntrophic associations resulting in acetogenesis from stearate (sm) and oleate (om) were obtained from the sludges of a sewage digestor. in both cases, methanospirillum hungatei together with short, motile, gram-negative, nonfluorescent rods morphologically similar to syntrophomonas wolfei were identified by microscopic examination. besides growing on volatile fatty acids (butyrate through caproate), both cultures grew on oleate (c(18:1)) and numerous even-numbered, saturate ...	1985	16346761
isolation of a butyrate-utilizing bacterium in coculture with methanobacterium thermoautotrophicum from a thermophilic digester.	sludge from a thermophilic, 55 degrees c digester produced methane without a lag period when enriched with butyrate. the sludge was found by most-probable-number enumeration to have ca. 5 x 10 butyrate-utilizing bacteria per ml. a thermophilic butyrate-utilizing bacterium was isolated in coculture with methanobacterium thermoautotrophicum. this bacterium was a gram-negative, slightly curved rod, occurred singly, was nonmotile, and did not appear to produce spores. when this coculture was incubat ...	1985	16346813
effect of gramicidin on methanogenesis by various methanogenic bacteria.	methanogenesis by methanobacterium thermoautotrophicum strains was extremely sensitive to gramicidin, total inhibition being observed at 0.2 mug/ml. in contrast, methane synthesis by methanococcus voltae, methanogenium marisnigri, methanosarcina mazei, and methanospirillum hungatei were resistant to the highest concentrations of gramicidin tested (40 mug/ml), although spheroplasts of methanospirillum hungatei were extremely sensitive. other species tested showed intermediate sensitivity to grami ...	1985	16346835
pa-1, a versatile anaerobe obtained in pure culture, catabolizes benzenoids and other compounds in syntrophy with hydrogenotrophs, and p-2 plus wolinella sp. degrades benzenoids.	methanogenic enrichments catabolizing 13 mm phenylacetate or 4 mm phenol were established at 37 degrees c, using a 10% inoculum from a municipal anaerobic digester. by using agar roll tubes of the basal medium plus 0.1% yeast extract-25 mm fumarate, a hydrogenotrophic lawn of wolinella succinogenes and phenol or phenylacetate, strains p-2 and pa-1, respectively, were isolated in coculture with w. succinogenes. with the lawn deleted, pa-1 was isolated in pure culture. strain p-2 is apparently a n ...	1985	16346852
crystalline order to high resolution in the sheath of methanospirillum hungatei: a cross-beta structure.	electron microscopy and electron diffraction indicate that the outer sheath of the cell wall of the archaebacterium methanospirillum hungatei contains a two-dimensional crystalline lattice having, at least to low resolution, p2 symmetry in projection with a = 5.66 nm, b = 2.81 nm and gamma = 85.6 degrees. at a resolution of 2 nm, the unit cell contains two lobes, whereas high-angle electron diffraction shows the presence of a substantial quantity of beta structure, with the 0.47 nm spacing (betw ...	1985	3927007
three-dimensional architecture of the cell sheath and septa of methanospirillum hungatei.	the methanogenic bacterium methanospirillum hungatei exists as filaments which have a very unusual cell wall architecture, comprising a long cylindrical sheath within which there may be many individual cells arranged in a line. the sheath has a two-dimensional crystalline structure, and the cells are separated within the tube by septa which also have a crystalline structure. we have used computer image processing of tilted-view electron micrographs to analyze the structure in negative stains of ...	1985	3968038
unusual stability of the methanospirillum hungatei sheath.	the proteinaceous sheath of methanospirillum hungatei was isolated by lysing cells in 50 mm dithiothreitol, separating the sheath from other cellular material by discontinuous sucrose density centrifugation, and removing the "cell spacers" with dilute naoh. the isolated sheath material consisted of hollow tubes which had a highly ordered surface array. the stability of the sheath to treatment with denaturants and to enzymatic digestion was examined by a turbidimetric assay in conjunction with el ...	1985	3988711
amino acid biosynthesis and sodium-dependent transport in methanococcus voltae, as revealed by 13c nmr.	of several methanogenic bacteria examined only methanococcus voltae readily incorporated exogenous amino acids into cell protein. this was easily shown, since growth in the presence of exogenous amino acids resulted in a loss of signal intensities from those carbon atoms normally labelled by [13c]acetate during biosynthesis. from 80% to 95% of the ser, lys, pro or val incorporated into protein could be supplied directly from the growth medium. in contrast, asp and glu, if supplied to the medium, ...	1985	3996416
methanogenesis and the k+ transport system are activated by divalent cations in ammonia-treated cells of methanospirillum hungatei.	we describe a k+ transport system in methanospirillum hungatei cells depleted of cytoplasmic k+ via an ammonia/k+ exchange reaction (sprott, g. d., shaw, k. m., and jarrell, k. f. (1984) j. biol. chem. 259, 12602-12608). ammonia-treated cells contained low concentrations of atp and were unable to make ch4 or to transport 86rb+. all of these properties were restored by cacl2, mgcl2, or mncl2, and not by cocl2 or nicl2. the rb+ transport system had a km of 0.42 and vmax of 29 nmol/min x mg; k+ inh ...	1985	4019470
preparation of cell-free extracts and the enzymes involved in fatty acid metabolism in syntrophomonas wolfei.	syntrophomonas wolfei is an anaerobic fatty acid degrader that can only be grown in coculture with h2-using bacteria such as methanospirillum hungatei. cells of s. wolfei were selectively lysed by lysozyme treatment, and unlysed cells of m. hungatei were removed by centrifugation. the cell extract of s. wolfei obtained with this method had low levels of contamination by methanogenic cofactors. however, lysozyme treatment was not efficient in releasing s. wolfei protein; only about 15% of the l-3 ...	1986	3459726
31p-nmr spectra of methanogens: 2,3-cyclopyrophosphoglycerate is detectable only in methanobacteria strains.	the unique compound 2,3-cyclopyrophosphoglycerate occurs at a detectable concentration in the genera methanobacterium and methanobrevibacter but not in methanococcus, methanospirillum and methanosarcina, as shown by a 31p-nmr survey of several different methanogens. metabolic poisons (carbonyl cyanide m-chlorophenylhydrazone and valinomycin) do not decrease the level of the cyclic pyrophosphate in methanobacterium thermoautotrophicum; therefore, it cannot be a phosphagen, i.e., an energy storage ...	1986	3754772
relationship of formate to growth and methanogenesis by methanococcus thermolithotrophicus.	methanococcus thermolithotrophicus is a methanogenic archaebacterium that can use either h2 or formate as its source of electrons for reduction of co2 to methane. growth and suspended-whole-cell experiments show that h2 plus co2 methanogenesis was constitutive, while formate methanogenesis required adaptation time; selenium was necessary for formate utilization. cells grown on formate had 20 to 100 times higher methanogenesis rates on formate than cells grown on h2-co2 and transferred into forma ...	1986	3098165
growth of methanogenic bacteria in pure culture with 2-propanol and other alcohols as hydrogen donors.	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. stoichiometric measurements revealed formation of 1 mol of ch(4) by co(2) reduction, with 4 mol of 2-propanol being converted to acetone. in addition to 2-propanol, the isolates use ...	1986	16347050
palladium-mediated hydrogenation of unsaturated hydrocarbons with hydrogen gas released during anaerobic cellulose degradation.	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 inhibited growth of neocallimastix frontalis and partly inhibited ruminococcus albus. lindlar catalyst (40 to 200 mg per tube) suspended in a glass pouch above the culture medium did ...	1986	16347167
separation of syntrophomonas wolfei from methanospirillum hungatii in syntrophic cocultures by using percoll gradients.	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 and had low levels of contamination by the methanogenic cofactor, factor(420), were obtained.	1987	16347346
proton-motive-force-driven formation of co from co2 and h2 in methanogenic bacteria.	cell suspensions of methanogenic bacteria (methanosarcina barkeri, methanospirillum hungatei, methano-brevibacter arboriphilus, and methanobacterium thermoautotrophicum) were found to form co from co2 and h2 according to the reaction: co2 + h2----co + h2o; delta g0 = +20 kj/mol. up to 15,000 ppm co in the gas phase were reached which is significantly higher than the equilibrium concentration calculated from delta g0 (95 ppm under the experimental conditions). this indicated that co2 reduction wi ...	1987	2822415
inhibition of methanogenesis in pure cultures by ammonia, fatty acids, and heavy metals, and protection against heavy metal toxicity by sewage sludge.	the effect of ammonium chloride, sodium butyrate, sodium propionate, and the heavy metals nickel, zinc, and copper on methanogenesis by pure cultures of methanospirillum hungatei, methanosarcina barkeri, methanobacterium thermoautotrophicum, and methanobacterium formicicum at ph 6.5 was studied. the latter three strains were resistant to greater than 60 g/l of the volatile fatty acids and to greater than 10 g/l of nh3 n. methanospirillum hungatei was somewhat more sensitive with 50% inhibition o ...	1987	3621086
isolation of flagella from the archaebacterium methanococcus voltae by phase separation with triton x-114.	the flagella of methanococcus voltae were isolated by using three procedures. initially, cells were sheared to release the filaments, which were purified by differential centrifugation and banding in kbr gradients. flagella were also prepared by solubilization of cells with 1% (vol/vol) triton x-100 and purified as described above. both of these techniques resulted in variable recovery and poor yield of flagellar filaments. purification of intact flagella (filament, hook, and basal body) was ach ...	1988	3127380
physiological and 15n-nmr analysis of molecular nitrogen fixation by methanococcus thermolithotrophicus, methanobacterium bryantii and methanospirillum hungatei.	two mesophilic methanogenic bacteria, methanobacterium bryantii strain moh and methanospirillum hungatei strain gp1 were demonstrated, using several different experimental approaches, to fix dinitrogen. evidence includes (1) growth with n2 as the sole nitrogen source; (2) incorporation of 15n2 into cellular material (both soluble amino acid pools and insoluble cell protein and other macromolecules) detected by 15n-nmr spectroscopy; (3) acetylene reduction to ethylene by the cells, and inhibition ...	1988	3167101
7-methylpterin derivatives in extracts of methanogens characterized by a relatively low methanopterin content.	cofactor extracts of five hydrogenotrophic methanogenic bacteria which contain relatively low amounts of methanopterin were screened for the presence of 7-methylpterin derivatives. extracts of methanospirillum hungatei, methanobrevibacter smithii and methanoplanus endosymbiosus were found to contain 7-methylpterin and methanopterin. these compounds were absent in extracts of methanogenium thermophilicum and methanogenium tatii. an unidentified methanopterin-like compound was detected in extracts ...	1988	3255348
ethane production by methanosarcina barkeri during growth in ethanol supplemented medium.	methanosarcina barkeri strain 227 produced ethane during growth on h2/co2 when ethanol was added to the medium in concentrations of 89-974 mm; ethane production varied from 14 to 38 nmoles per tube (20 ml gas phase, 5.7 ml liquid) with increasing ethanol concentrations. cells grown to mid-logarithmic phase (a600 approximately 0.46, protein = 64 micrograms/ml) on h2/co2, thoroughly flushed with h2/co2, then exposed to ethanol, produced maximal ethane levels (at 585 and 974 mm ethanol) of about 21 ...	1988	3395108
bioenergetic conditions of butyrate metabolism by a syntrophic, anaerobic bacterium in coculture with hydrogen-oxidizing methanogenic and sulfidogenic bacteria.	the butyrate-oxidizing, proton-reducing, obligately anaerobic bacterium nsf-2 was grown in batch cocultures with either the hydrogen-oxidizing bacterium methanospirillum hungatei pm-1 or desulfovibrio sp. strain ps-1. metabolism of butyrate occurred in two phases. the first phase exhibited exponential growth kinetics (phase a) and had a doubling time of 10 h. this value was independent of whether nsf-2 was cultured with a methanogen or a sulfate reducer and likely represents the maximum specific ...	1988	16347645
phospholipid fatty acid composition of the syntrophic anaerobic bacterium syntrophomonas wolfei.	the membrane phospholipid fatty acids (plfas) from several cocultures and a pure culture of syntrophomonas wolfei were determined by capillary column gas chromatography. cocultures of s. wolfei with a desulfovibrio sp. contained plfas from both organisms, whereas plfas from a coculture with methanospirillum hungatei contained very little biomass to analyze. the pure culture of s. wolfei grown on crotonate provided the best material for analysis of the plfas. the predominant plfas of s. wolfei we ...	1988	16347667
acetate inhibition of methanogenic, syntrophic benzoate degradation.	acetate inhibited benzoate degradation by a syntrophic coculture of an anaerobic benzoate degrader (strain bz-2) and methanospirillum strain pm-1; the apparent k(i) for acetate was approximately 40 mm. the addition of acetate resulted in a decrease in the hydrogen concentration in the coculture, indicating that phenomena related to interspecies hydrogen transfer affected this value and that the effect of acetate on the benzoate-degrading partner was probably greater than the apparent k(i) for th ...	1988	16347699
chemotaxis in methanospirillum hungatei.	methanospirillum hungatei gave a positive chemotactic response to acetate.	1989	16347829
effects of organic acid anions on the growth and metabolism of syntrophomonas wolfei in pure culture and in defined consortia.	the effects of organic acid anions on the growth of syntrophomonas wolfei was determined by varying the initial concentration of the acid anion in the medium. the addition of 15 mm acetate decreased the growth rate of a butyrate-catabolizing coculture containing methanospirillum hungatei from 0.0085 to 0.0029 per hour. higher initial acetate concentrations decreased the butyrate degradation rate and the yield of cells of s. wolfei per butyrate degraded. inhibition was not due to the counter ion ...	1989	16347899
isolation and ultrastructure of the flagella of methanococcus thermolithotrophicus and methanospirillum hungatei.	the flagella of the archaebacteria methanococcus thermolithotrophicus and methanospirillum hungatei enter the cells in regions with ultrastructure resembling that of the polar organelles found in a variety of eubacteria. flagella of both organisms consist of a filament, a hook, and a basal body with two rings similar to those of gram-positive eubacteria. the integrity of the flagella of m. thermolithotrophicus is lost in the absence of high salt concentrations, and those of both organisms are un ...	1989	16347934
characterization of the microbial community colonizing the anal and vulvar pores of helminths from the hindgut of zebras.	scanning and transmission electron microscopy were used to examine the adherence and in situ morphology of the microbial community colonizing the anal and vulvar pores of the subfamily cyathostominae (nematoda: strongylidae) from the colon of burchell's zebra (equus burchelli antiquorum). two different morphological types of asporogenous rod were prominent in the microbial community. one was a thin, septate, filamentous organism (0.4 to 0.5 micron by 2 to 3 microns) with blunt ends, which was mo ...	1989	2667460
growth of the syntrophic anaerobic acetogen, strain pa-1, with glucose or succinate as energy source.	strain pa-1 (s. barik, w.j. brulla, and m.p. bryant, appl. environ. microbiol. 50:304-310, 1985) is an anaerobic, gram-negative rod that in pure culture decarboxylates succinate to propionate and that grows syntrophically as an acetogen with the h2 utilizer methanospirillum hungatei if glucose, pyruvate, aspartate, or fumarate is provided. in pure culture, strain pa-1 grows optimally in a medium containing 5% ruminal fluid, 0.1% yeast extract, a 4:1 n2-co2 gas phase, and 20 mm succinate. with th ...	1989	2757384
conserved n-terminal sequences in the flagellins of archaebacteria.	methanococcus voltae produces two flagellins of molecular weight 31,000 and 33,000. amino acid analysis as well as peptide mapping with cyanogen bromide, chymotrypsin and staphylococcus aureus v-8 protease indicates that the two flagellins are distinct. n-terminal sequencing of the 31,000 mc. voltae flagellin as well as the 24,000 and 25,000 molecular weight flagellins of methanospirillum hungatei gp1 shows an extensive homology with the reported n-terminus of the flagellins from halobacterium h ...	1990	2106880
high-resolution topography of the s-layer sheath of the archaebacterium methanospirillum hungatei provided by scanning tunneling microscopy.	the inner and outer surfaces of the sheath of methanospirillum hungatei gp1 have been imaged for the first time by using a bimorph scanning tunneling microscope (stm) on platinum-coated or uncoated specimens to a nominal resolution in height of ca. 0.4. nm. unlike more usual types of microscopy (e.g., transmission electron microscopy), stm provided high-resolution topography of the surfaces, giving good depth detail which confirmed the sheath to be a paracrystalline structure possessing minute p ...	1990	2121719
isolation, characterization, and cellular insertion of the flagella from two strains of the archaebacterium methanospirillum hungatei.	in high (45 mm)-phosphate medium, methanospirillum hungatei strains gp1 and jf1 grew as very long, nonmotile chains of cells that did not possess flagella. however, growth in lower (3 or 30 mm)-phosphate medium resulted in the production of mostly single cells and short chains that were motile by means of two polar tufts of flagella, which transected the multilayered terminal plug of the cell. electron microscopy of negatively stained whole mounts revealed a flagellar filament diameter of approx ...	1990	2345143
anaerobic degradation of 1,3-propanediol by sulfate-reducing and by fermenting bacteria.	three strains of strictly anaerobic gram-negative, non-sporeforming, motile bacteria were enriched and isolated from freshwater sediments with 1,3-propanediol as sole energy and carbon source. strain ottpdl was a sulfate-reducing bacterium which grew also with lactate, ethanol, propanol, butanol, 1,4-butanediol, formate or hydrogen plus co2, the latter only in the presence of acetate. in the absence of sulfate, most of these substrates were fermented to the respective fatty acids in syntrophic c ...	1990	2353806
assignment of clostridium bryantii to syntrophospora bryantii gen. nov., comb. nov. on the basis of a 16s rrna sequence analysis of its crotonate-grown pure culture.	the clostridium bryantii-methanospirillum hungatei syntrophic coculture, grown on caproate, was adapted to grow on crotonate. then, c. bryantii was isolated in pure culture from crotonate bottle plates. a 16s rrna sequence analysis of the pure subculture revealed that, as a member of the gram-positive phylum, it was not closely related to any of the clostridium species with which it was compared or to any of the other clusters in the gram-positive phylum with which it was compared. however, it w ...	1990	1699595
ultrastructure, inferred porosity, and gram-staining character of methanospirillum hungatei filament termini describe a unique cell permeability for this archaeobacterium.	by light microscopy, methanospirillum hungatei gp1 stains gram positive at the terminal ends of each multicellular filament and gram negative at all regions in between. this phenomenon was studied further by electron microscopy and energy-dispersive x-ray spectroscopy of gram-stained cells, using a platinum compound to replace gram's iodine (j. a. davies, g. k. anderson, t. j. beveridge, and h. c. clark, j. bacteriol. 156:837-845, 1983). crystal violet-platinum precipitates could be found only i ...	1991	1702777
dissolution and immunochemical analysis of the sheath of the archaeobacterium methanospirillum hungatei gp1.	the sheath of methanospirillum hungatei gp1 was degraded by three dissolution techniques, which produced a range of soluble products. by using 0.05 m l-arginine buffer (ph 12.6) at 90 degrees c for 10 min, 74% (dry weight) of the sheath was dissolved; however, the solubilized polypeptides were extensively degraded. treatment with 2% beta-mercaptoethanol and 2% sodium dodecyl sulfate at 90 degrees c in 0.05 m 2(n-cyclohexylamino)ethanesulfonic acid (ches) buffer (ph 9.0) solubilized 42% (dry weig ...	1991	1717435
inhibition of pure cultures of methanogens by benzene ring compounds.	the inhibition of methane production by methanosaeta concilii gp6, methanospirillum hungatei gp1, methanobacterium espanolae gp9, and methanobacterium bryantii m.o.h. during short-term (6-h) exposure to eight benzene ring compounds was studied. the concentration that caused 50% inhibition of the methane production rate (ic50) was dependent on the species and the toxicant. pentachlorophenol was the most toxic of the tested compounds, with an ic50 of less than 8 mg/liter for all species except m. ...	1991	1746956
effect of propionate toxicity on methanogen-enriched sludge, methanobrevibacter smithii, and methanospirillum hungatii at different ph values.	the effect of propionate toxicity at different ph values (6.5, 7.0, and 8.0) on methanogen-enriched sludge. methanobrevibacter smithii, and methanospirillum hungatii was studied. organisms were grown in balch medium 3 in hungate tubes, and toxicity was characterized by a decrease in production of methane and in bacterial numbers. propionate inhibited bacterial growth and cumulative methane production at concentrations as low as 20 mm. in the absence of propionate, the methanogen-enriched sludge ...	1991	1872605
bacteriological composition and structure of granular sludge adapted to different substrates.	the bacteriological composition and ultrastructure of mesophilic granular methanogenic sludge from a large-scale upflow anaerobic sludge blanket reactor treating wastewater from a sugar plant and of sludge granules adapted to ethanol and propionate were studied by counting different bacterial groups and by immunocytochemical methods. propionate-grown granular sludge consisted of two types of clusters, those of a rod-shaped bacterium immunologically related to methanothrix soehngenii and those co ...	1991	1892385
the sequence of methanospirillum hungatei 23s rrna confirms the specific relationship between the extreme halophiles and the methanomicrobiales.	we have determined the sequence of the 23s rrna from the methanogenic archaeon methanospirillum hungatei. this is the first such sequence from a member of the methanomicrobiales. moreover, it brings additional evidence to bear on the possible specific relationship between this particular group of methanogens and the extreme halophiles. such evidence is critical in that several new (and relatively untested) methods of phylogenetic inference have lead to the controversial conclusion that the ex ...	1991	11540074
reciprocal isomerization of butyrate and isobutyrate by the strictly anaerobic bacterium strain wog13 and methanogenic isobutyrate degradation by a defined triculture.	isomerization of butyrate and isobutyrate was investigated with the recently isolated strictly anaerobic bacterium strain wog13 which ferments glutarate to butyrate, isobutyrate, co(2), and small amounts of acetate. dense cell suspensions converted butyrate to isobutyrate and isobutyrate to butyrate. c-nuclear magnetic resonance experiments proved that this isomerization was accomplished by migration of the carboxyl group to the adjacent carbon atom. in cell extracts, both butyrate and isobutyra ...	1992	16348708
characterization of novel, phenol-soluble polypeptides which confer rigidity to the sheath of methanospirillum hungatei gp1.	treatment of the methanospirillum hungatei gp1 sheath with 90% (wt/vol) phenol resulted in the solubilization of a novel phenol-soluble group of polypeptides. these polypeptides were purified by the removal of insoluble material by ultracentrifugation and represented approximately 19% of the mass of the sheath. the phenol-insoluble material resembled untreated sheath but had lost its rigidity and cylindrical form. recombination of phenol-soluble and phenol-insoluble fractions by dialysis to remo ...	1992	1732226
detection of growth sites in and protomer pools for the sheath of methanospirillum hungatei gp1 by use of constituent organosulfur and immunogold labeling.	methanospirillum hungatei gp1 integrated approximately 9% of cellular [35s]cysteine into its sheath. autoradiography of sodium dodecyl sulfate-polyacrylamide gels revealed that [35s]cysteine was confined to the proteins released by the sodium dodecyl sulfate-beta-mercaptoethanol-edta solubilization method (g. southam and t. j. beveridge, j. bacteriol. 173:6213-6222, 1991) and was not present in the proteins released by treatment with phenol (g. southam and t. j. beveridge, j. bacteriol. 174:935- ...	1992	1400199
formation of unilamellar liposomes from total polar lipid extracts of methanogens.	unilamellar liposomes were formed by controlled detergent dialysis of mixed micelles consisting of acetone-insoluble total polar lipids extracted from various methanogens and the detergent n-octyl-beta-d-glucopyranoside. the final liposome populations were studied by dynamic light scattering and electron microscopy. unilamellar liposomes with mean diameters smaller than 100 nm were obtained with lipid extracts of methanococcus voltae, methanosarcina mazei, methanosaeta concilii, and methanococcu ...	1992	1444403
monolayer properties of archaeol and caldarchaeol polar lipids of a methanogenic archaebacterium, methanospirillum hungatei, at the air/water interface.	monolayer studies at the air/water interface were carried out on the major tetraether (caldarchaeol-) derived phosphoglycolipid, glcp-alpha(1-2)-galf-beta(1-1)-caldarchaeol-phosphoglycerol (pgc-i), the major diether (archaeol-) derived glycolipid, glcp-alpha(1-2)-galf-beta(1-1)-archaeol (dga-i), the major archaeol-derived phospholipids, phosphatidyl-n,n dimethylaminopentanetetrol (ppdaa) and phosphatidyl-n,n,n-trimethylaminopentanetetrol (pptaa) and the minor caldarchaeol-derived glycolipid, glc ...	1992	1486655
relatedness of the flagellins from methanogens.	purified flagellar filaments isolated from six methanogens were composed of multiple flagellins. two flagellins were present in methanococcus deltae (mr = 34,000 and 32,000), methanoculleus marisnigri (mr = 31,000 and 25,500) and methanococcus jannaschii (mr = 31,000 and 27,500), three in methanothermus fervidus (mr = 34,000, 25,000 and 24,000) and four or more in both methanococcus vannielii and methanococcus maripaludis (mr ranging from 27,500 to 32,000). the flagellins of m. fervidus and m. d ...	1992	1503530
correlation between glycosylation of flagellin proteins and sensitivity of flagellar filaments to triton x-100 in methanogens.	the flagellins of methanospirillum hungatei strains jf1 and gp1, methanococcus deltae, and methanothermus fervidus are glycosylated. isolated flagellar filaments from these organisms are dissociated by low concentrations (0.5% (v/v)) of triton x-100. flagellar filaments from other methanogens (methanococcus voltae, methanococcus vannielii and methanoculleus marisnigri) composed of non-glycosylated flagellins are resistant to triton x-100 treatment. consequently, the isolation techniques (employi ...	1992	1537540
hydrogen formation from glycolate driven by reversed electron transport in membrane vesicles of a syntrophic glycolate-oxidizing bacterium.	oxidation of glycolate to 2 co2 and 3 h2 (delta g degrees' = +36 kj/mol glycolate) by the proton-reducing, glycolate-fermenting partner bacterium of a syntrophic coculture (strain flglym) depends on a low hydrogen partial pressure (ph2). the first reaction, glycolate oxidation to glyoxylate (e zero' = -92 mv) with protons as electron acceptors (e zero' = -414 mv), is in equilibrium only at a ph2 of 1 micropa which cannot be maintained by the syntrophic partner bacterium methanospirillum hungatei ...	1993	8223560
characterization of the cell wall of the sheathed methanogen methanospirillum hungatei gp1 as an s layer.	the cell wall of methanospirillum hungatei gp1 is a labile structure that has been difficult to isolate and characterize because the cells which it encases are contained within a sheath. cell-sized fragments, 560 nm wide by several micrometers long, of cell wall were extracted by a novel method involving the gradual drying of the filaments in 2% (wt/vol) sodium dodecyl sulfate and 10% (wt/vol) sucrose in 50 mm n-2-hydroxyethylpiperazine-n'-2-ethanesulfonic acid (hepes) buffer containing 10 mm ed ...	1993	8244924
dichloromethane as the sole carbon source for an acetogenic mixed culture and isolation of a fermentative, dichloromethane-degrading bacterium.	dichloromethane (dcm) is utilized by the strictly anaerobic, acetogenic mixed culture dm as a sole source of carbon and energy for growth. growth with dcm was linear, and cell suspensions of the culture degraded dcm with a specific activity of 0.47 mkat/kg of protein. a mass balance of 2 mol of chloride and 0.42 mol of acetate per mol of dcm was observed. the dehalogenation reaction showed similar specific activities under both anaerobic and aerobic conditions. radioactivity from [14c]dcm in cel ...	1993	8285685
freeze-fracture planes of methanogen membranes correlate with the content of tetraether lipids.	methanospirillum hungatei gp1 contained 50% of its ether core lipids (polar lipids less head groups) as tetraether lipids, and its plasma membrane failed to fracture along its hydrophobic domain during freeze-etching. the membrane of methanosaeta ("methanothrix") concilii did not contain tetraether lipids and easily fractured to reveal typical intramembranous particles. methanococcus jannaschii grown at 50 degrees c contained 20% tetraether core lipids, which increased to 45% when cells were gro ...	1993	8432712
transmission electron microscopy, scanning tunneling microscopy, and atomic force microscopy of the cell envelope layers of the archaeobacterium methanospirillum hungatei gp1.	methanospirillum hungatei gp1 possesses paracrystalline cell envelope components including end plugs and a sheath formed from stacked hoops. both negative-stain transmission electron microscopy (tem) and scanning tunneling microscopy (stm) distinguished the 2.8-nm repeat on the outer surface of the sheath, while negative-stain tem alone demonstrated this repeat around the outer circumference of individual hoops. thin sections revealed a wave-like outer sheath surface, while stm showed the presen ...	1993	8458836
growth of syntrophic propionate-oxidizing bacteria with fumarate in the absence of methanogenic bacteria.	oxidation of succinate to fumarate is an energetically difficult step in the biochemical pathway of propionate oxidation by syntrophic methanogenic cultures. therefore, the effect of fumarate on propionate oxidation by two different propionate-oxidizing cultures was investigated. when the methanogens in a newly enriched propionate-oxidizing methanogenic culture were inhibited by bromoethanesulfonate, fumarate could act as an apparent terminal electron acceptor in propionate oxidation. c-nuclear ...	1993	16348912
assignment of fatty acid-beta-oxidizing syntrophic bacteria to syntrophomonadaceae fam. nov. on the basis of 16s rrna sequence analyses.	after enrichment from chinese rural anaerobic digestor sludge, anaerobic, sporing and nonsporing, saturated fatty acid-beta-oxidizing syntrophic bacteria were isolated as cocultures with h2- and formate-utilizing methanospirillum hungatei or desulfovibrio sp. strain g-11. the syntrophs degraded c4 to c8 saturated fatty acids, including isobutyrate and 2-methylbutyrate. they were adapted to grow on crotonate and were isolated as pure cultures. the crotonate-grown pure cultures alone did not gr ...	1993	11536533
regulation of product formation in bacteroides xylanolyticus x5-1 by interspecies electron transfer.	bacteroides xylanolyticus x5-1 was grown in pure culture and in mixed culture with methanospirillum hungatei jf-1 under xylose limitation in the chemostat. in the pure culture, ethanol, acetate, co(2), and hydrogen were the products. in the mixed culture, acetate, co(2), and presumably hydrogen were the only products formed by b. xylanolyticus x5-1. the biomass yield of b. xylanolyticus x5-1 increased because of cocultivation. in cell extracts of the pure culture, both nad- and nadp-dependent ac ...	1994	16349240
anaerobic degradation of propionate by a mesophilic acetogenic bacterium in coculture and triculture with different methanogens.	a mesophilic acetogenic bacterium (mpob) oxidized propionate to acetate and co(2) in cocultures with the formate- and hydrogen-utilizing methanogens methanospirillum hungatei and methanobacterium formicicum. propionate oxidation did not occur in cocultures with two methanobrevibacter strains, which grew only with hydrogen. tricultures consisting of mpob, one of the methanobrevibacter strains, and organisms which are able to convert formate into h(2) plus co(2) (desulfovibrio strain g11 or the ho ...	1994	16349350
cofactor contents of methanogenic bacteria reviewed.	the content of specific methanogenic cofactors was assessed for a range of hydrogenotrophic and methylotrophic methanogenic bacteria grown on different substrates using high performance liquid chromatography. in general, all methanogens were found to contain coenzyme f420 analogues, methanopterin (mpt) analogues and 5-hydroxybenzimidazolylcobamide (vitamin b12-hbi). in hydrogenotrophic methanogens of the genera methano-bacterium and methanobrevibacter, as a rule, coenzymes f420-2 and f420-3 as w ...	1994	7916957
tetraether lipids of methanospirillum hungatei with head groups consisting of phospho-n,n-dimethylaminopentanetetrol, phospho-n,n,n-trimethylaminopentanetetrol, and carbohydrates.	acyclic, standard tetraether and diether lipids each account for about 50% of the total ether lipids found in methanospirillum hungatei. sixteen ether lipids were purified and defined according to relative weight percentage and staining reactions on thin-layer plates. structures were elucidated for six previously uncharacterized tetraether lipids. four of these lipids had as one head group either alpha-glcp-(1-2)-beta-gal(f)-, or beta-gal(f)-(1-6)-beta-gal(f)-, in glycosidic linkage to the first ...	1994	7918605
physical characterization of the flagella and flagellins from methanospirillum hungatei.	flagellar filaments from methanospirillum hungatei gp1 and jf1 were isolated and subjected to a variety of physical and chemical treatments. the filaments were stable to temperatures up to 80 degrees c and over the ph range of 4 to 10. the flagellar filaments were dissociated in the detergents (final concentration of 0.5%) triton x-100, tween 20, tween 80, brij 58, n-octylglucoside, cetyltrimethylammonium bromide, and zwittergent 3-14, remaining intact in only two of the detergents tested, sodiu ...	1994	8002572
acetogenesis from dichloromethane by a two-component mixed culture comprising a novel bacterium.	a strictly anaerobic two-component culture able to grow exponentially with a doubling time of 20 h on a medium containing dichloromethane as the carbon and energy source was characterized. on a medium without sulfate, we observed (per mol of dichloromethane) a mass balance of 2 mol of chloride, 0.26 mol of acetate, 0.05 mol of formate, and 0.25 mol of carbon in biomass. one component of the culture, strain dmb, was identified by a 16s ribosomal dna analysis as a desulfovibrio sp. the other compo ...	1995	16535097
role of formate and hydrogen in the degradation of propionate and butyrate by defined suspended cocultures of acetogenic and methanogenic bacteria.	the butyrate-degrading syntrophospora bryantii degrades butyrate and a propionate-degrading strain (mpob) degrades propionate in coculture with the hydrogen- and formate-utilizing methanospirillum hungatii or methanobacterium formicicum. however, the substrates are not degraded in constructed cocultures with two methanobrevibacter arboriphilus strains which are only able to consume hydrogen. pure cultures of the acetogenic bacteria form both hydrogen and formate during butyrate oxidation with pe ...	1995	8821782
scanning probe microscopy in microbiology.	scanning probe microscopy (spm) is emerging as an important alternative to electron microscopy as a technique for analyzing submicron details on biological surfaces. microbiological specimens such as viruses, bacteriophages, and ordered bacterial surface layers and membranes have played an important role in the development of scanning tunnelling microscopy (stm) and atomic force microscopy (afm) in cellular and molecular biology. early stm studies involving metal-coated bacteriophage t4 polyhead ...	1995	8574524
involvement of a single periplasmic hydrogenase for both hydrogen uptake and production in some desulfovibrio species.	various sulphate-reducing bacteria differing in the number of genes encoding hydrogenase were shown to ferment lactate in coculture with methanospirillum hungatei, in the absence of sulphate. the efficiency of interspecies h2 transfer carried out by these species of sulphate-reducing bacteria does not appear to correlate with the distribution of genes coding for hydrogenase. desulfovibrio vulgaris groningen, which possesses only the gene for [nife] hydrogenase, oxidizes hydrogen in the presence ...	1995	7652207