| 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 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| spheroplasts of methanospirillum hungatii formed upon treatment with dithiothreitol. | | 1979 | 38895 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| modeling and measuring the elastic properties of an archaeal surface, the sheath of methanospirillum hungatei, and the implication of methane production. | we describe a technique for probing the elastic properties of biological membranes by using an atomic force microscope (afm) tip to press the biological material into a groove in a solid surface. a simple model is developed to relate the applied force and observed depression distance to the elastic modulus of the material. a measurement on the proteinaceous sheath of the archaebacterium methanospirillum hungatei gp1 gave a young's modulus of 2 x 10(10) to 4 x 10(10) n/m2. the measurements sugges ... | 1996 | 8655487 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| the presence of h+ and na(+)-translocating atpases in methanobacterium thermoautotrophicum and their possible function under alkaline conditions. | two atpases with different apparent molecular masses of approx. 500 kda and 400 kda were identified in the edta extract of the cell membranes of methanobacterium thermoautotrophicum. western blotting with polyclonal antiserum reactive with beta-subunit of mitochondrial atpase from rat liver and yeast was used for further analysis of these atpases. a strong crossreactivity with a single protein band with an apparent molecular weight of about 53 kda (similar to beta-subunit of f-type atpase from o ... | 1995 | 7672109 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| phylogenetic analyses of some extremely halophilic archaea isolated from dead sea water, determined on the basis of their 16s rrna sequences. | twenty-two extremely halophilic aerobic archaeal strains were isolated from enrichments prepared from dead sea water samples collected 57 years ago. the isolates were phenotypically clustered into five different groups, and a representative from each group was chosen for further study. almost the entire sequences of the 16s rrna genes of these representatives, and of haloarcula hispanica atcc 33960, were determined to establish their phylogenetic positions. the sequences of these strains were co ... | 1996 | 8837434 |
| activation and degradation of benzoate, 3-phenylpropionate and crotonate by syntrophus buswellii strain ga. evidence for electron-transport phosphorylation during crotonate respiration. | a strictly anaerobic, benzoate-degrading bacterium, syntrophus buswellii strain ga, was able to degrade benzoate or 3-phenylpropionate to acetate, co2 and h2, if the hydrogen partial pressure was sufficiently low. the hydrogen was removed in syntrophic coculture by methanospirillum hungatei or by desulfovibrio sp. through interspecies hydrogen transfer or in pure culture by the use of crotonate as reducible cosubstrate. alternatively, s. buswellii strain ga could grow in pure culture with croton ... | 1996 | 8867639 |
| the response of selected members of the archaea to the gram stain. | archaea possess a broader range of cell envelope structural formats than eubacteria and their cell walls do not contain peptidoglycan. some archaea have only a single s-layer as their cell wall (e.g. methanococcus jannaschii and sulfolobus acidocaldarius), whereas others have multiple layers (e.g. methanospirillum hungatei). sometimes there can also be a high proportion of tetraether lipids in membranes to make the envelope more resilient to environmental stress (e.g. methanococcus jannaschii an ... | 1996 | 8885405 |
| heat-shock response in methanosarcina mazei s-6. | the dnak locus of methanosarcina mazei s-6, a mesophilic organism of the phylogenetic domain archaea, contains the heat-shock genes 5'-grpe-dnak-dnaj-3'. parameters known to affect the response of these genes in organisms of the other two domains, bacteria and eucarya, were tested to determine their effects on the archaeal homologs. the mrna from the three genes increased after heat shock more in lamina than in single cells (these s-6 morphologic stages can be grown in the same substrate). singl ... | 1997 | 9216886 |
| anaerobic degradation of glycerol by desulfovibrio fructosovorans and d. carbinolicus and evidence for glycerol-dependent utilization of 1,2-propanediol | the degradation of glycerol by desulfovibrio carbinolicus and desulfovibrio fructosovorans was tested in pure culture with sulfate and in coculture with methanospirillum hungatei. desulfovibrio carbinolicus degraded glycerol into 3-hydroxypropionate with the formation of sulfide in pure culture and methane in the coculture. the maximum growth rates were 0.063 h-1 in pure culture and 0.014 h-1 in coculture (corresponding growth yields: 8.9 and 6.0 g dry weight/mol glycerol). with d. fructosovoran ... | 1998 | 9541565 |
| investigation of serine hydroxymethyltransferase in methanogens. | the cofactor specificity of serine hydroxymethyltransferase (shmt) activities was tested in extracts of several methanogens using tetrahydromethanopterin (h4mpt) from methanobacterium thermoautotrophicum marburg, tetrahydrosarcinapterin (h4spt) from methanosarcina barkeri, and tetrahydrofolate (h4folate) as the potential c1 carrier. in methanosphaera stadtmanae and methanococcus thermolithotrophicus, the activities were h4mpt dependent. in methanospirillum hungatei gp1, methanosaeta concilii, me ... | 1998 | 9783425 |
| syntrophobacter fumaroxidans sp. nov., a syntrophic propionate-degrading sulfate-reducing bacterium. | a syntrophic propionate-oxidizing bacterium, strain mpobt, was isolated from a culture enriched from anaerobic granular sludge. it oxidized propionate syntrophically in co-culture with the hydrogen- and formate-utilizing methanospirillum hungateii, and was able to oxidize propionate and other organic compounds in pure culture with sulfate or fumarate as the electron acceptor. additionally, it fermented fumarate. 16s rrna sequence analysis revealed a relationship with syntrophobacter wolinii and ... | 1998 | 9828440 |
| syntrophus aciditrophicus sp. nov., a new anaerobic bacterium that degrades fatty acids and benzoate in syntrophic association with hydrogen-using microorganisms. | strain sbt is a new, strictly anaerobic, gram-negative, nonmotile, non-sporeforming, rod-shaped bacterium that degrades benzoate and certain fatty acids in syntrophic association with hydrogen/formate-using microorganisms. strain sbt produced approximately 3 mol of acetate and 0.6 mol of methane per mol of benzoate in coculture with methanospirillum hungatei strain jf1. saturated fatty acids, some unsaturated fatty acids, and methyl esters of butyrate and hexanoate also supported growth of strai ... | 1999 | 9914307 |
| fluorescence in situ hybridization using 16s rrna-targeted oligonucleotides reveals localization of methanogens and selected uncultured bacteria in mesophilic and thermophilic sludge granules. | 16s rrna-targeted in situ hybridization combined with confocal laser scanning microscopy was used to elucidate the spatial distribution of microbes within two types of methanogenic granular sludge, mesophilic (35 degrees c) and thermophilic (55 degrees c), in upflow anaerobic sludge blanket reactors fed with sucrose-, acetate-, and propionate-based artificial wastewater. the spatial organization of the microbes was visualized in thin sections of the granules by using fluorescent oligonucleotide ... | 1999 | 10049894 |
| characterization of the anaerobic propionate-degrading syntrophs smithella propionica gen. nov., sp. nov. and syntrophobacter wolinii. | a strain of anaerobic, syntrophic, propionate-oxidizing bacteria, strain lypt (= ocm 661t; t = type strain), was isolated and proposed as representative of a new genus and new species, smithella propionica gen. nov., sp. nov. the strain was enriched from an anaerobic digestor and isolated. initial isolation was as a monoxenic propionate-degrading co-culture containing methanospirillum hungateii jf-1t as an h2- and formate-using partner. later, an axenic culture was obtained by using crotonate as ... | 1999 | 10319475 |
| culturable populations of sporomusa spp. and desulfovibrio spp. in the anoxic bulk soil of flooded rice microcosms. | most-probable-number (mpn) counts were made of homoacetogenic and other bacteria present in the anoxic flooded bulk soil of laboratory microcosms containing 90- to 95-day-old rice plants. mpn counts with substrates known to be useful for the selective enrichment or the cultivation of homoacetogenic bacteria (betaine, ethylene glycol, 2, 3-butanediol, and 3,4,5-trimethoxybenzoate) gave counts of 2.3 x 10(3) to 2.8 x 10(5) cells per g of dry soil. homoacetogens isolated from the terminal positive ... | 1999 | 10427044 |
| molecular characterization of a toluene-degrading methanogenic consortium. | a toluene-degrading methanogenic consortium enriched from creosote-contaminated aquifer material was maintained on toluene as the sole carbon and energy source for 10 years. the species in the consortium were characterized by using a molecular approach. total genomic dna was isolated, and 16s rrna genes were amplified by using pcr performed with kingdom-specific primers that were specific for 16s rrna genes from either members of the kingdom bacteria or members of the kingdom archaea. a total of ... | 1999 | 10584020 |
| [use of the level of g+c n dna for studying the molecular phylogeny o f methanogenic archaebacteria]. | a new method for theoretical analysis of the molecular phylogeny of bacteria, successfully applied earlier to nitrifying bacteria, was used to study the molecular phylogeny of methanogenic archaebacteria. the group studied included methanococcus igneus, methanococcus vannielii, methanothermus fervidus, methanolobus tindarius, methanobacterium formicicum, methanosarcina barkeri, methanobacterium thermoformicicum, methanoplanus limicola, methanospirillum hungatei, and methanobacterium thermoautotr ... | 1999 | 10624685 |
| desulfovirga adipica gen. nov., sp. nov., an adipate-degrading, gram-negative, sulfate-reducing bacterium. | a novel, mesophilic, gram-negative bacterium was isolated from an anaerobic digestor for municipal wastewater. the bacterium degraded adipate in the presence of sulfate, sulfite, thiosulfate and elemental sulfur. (e)-2-hexenedioate accumulated transiently in the degradation of adipate. (e)-2-hexenedioate, (e)-3-hexenedioate, pyruvate, lactate, c1-c12 straight-chain fatty acids and c2-c10 straight-chain primary alcohols were also utilized as electron donors. 3-phenylpropionate was oxidized to ben ... | 2000 | 10758870 |
| energetics of syntrophic propionate oxidation in defined batch and chemostat cocultures. | propionate consumption was studied in syntrophic batch and chemostat cocultures of syntrophobacter fumaroxidans and methanospirillum hungatei. the gibbs free energy available for the h(2)-consuming methanogens was <-20 kj mol of ch(4)(-1) and thus allowed the synthesis of 1/3 mol of atp per reaction. the gibbs free energy available for the propionate oxidizer, on the other hand, was usually >-10 kj mol of propionate(-1). nevertheless, the syntrophic coculture grew in the chemostat at steady-stat ... | 2000 | 10877789 |
| characterization of microbial consortia in a terephthalate-degrading anaerobic granular sludge system. | the microbial composition and spatial distribution in a terephthalate-degrading anaerobic granular sludge system were characterized using molecular techniques. 16s rdna clone library and sequence analysis revealed that 78.5% of 106 bacterial clones belonged to the delta subclass of the class proteobacteria; the remaining clones were assigned to the green non-sulfur bacteria (7.5%), synergistes (0.9%) and unidentified divisions (13.1%). most of the bacterial clones in the delta-proteobacteria for ... | 2001 | 11158354 |
| metabolism of benzoate, cyclohex-1-ene carboxylate, and cyclohexane carboxylate by "syntrophus aciditrophicus" strain sb in syntrophic association with h(2)-using microorganisms. | the metabolism of benzoate, cyclohex-1-ene carboxylate, and cyclohexane carboxylate by "syntrophus aciditrophicus" in cocultures with hydrogen-using microorganisms was studied. cyclohexane carboxylate, cyclohex-1-ene carboxylate, pimelate, and glutarate (or their coenzyme a [coa] derivatives) transiently accumulated during growth with benzoate. identification was based on comparison of retention times and mass spectra of trimethylsilyl derivatives to the retention times and mass spectra of authe ... | 2001 | 11282627 |
| 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 |
| 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 |
| 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 |
| chemical structure of a novel aminophospholipid from hydrogenobacter thermophilus strain tk-6. | the phospholipid composition of hydrogenobacter thermophilus strain tk-6, an obligately chemolithoautotrophic, extremely thermophilic hydrogen bacterium, was analyzed. two of four phospholipids detected from the strain were assumed to be phosphatidylinositol and phosphatidylglycerol. an aminophospholipid named px, whose content among the phospholipids was 65%, was found to have a novel chemical structure by analysis of the dilyso form with nuclear magnetic resonance and fast atom bombardment-mas ... | 2001 | 11591674 |
| benzoate fermentation by the anaerobic bacterium syntrophus aciditrophicus in the absence of hydrogen-using microorganisms. | the anaerobic bacterium syntrophus aciditrophicus metabolized benzoate in pure culture in the absence of hydrogen-utilizing partners or terminal electron acceptors. the pure culture of s. aciditrophicus produced approximately 0.5 mol of cyclohexane carboxylate and 1.5 mol of acetate per mol of benzoate, while a coculture of s. aciditrophicus with the hydrogen-using methanogen methanospirillum hungatei produced 3 mol of acetate and 0.75 mol of methane per mol of benzoate. the growth yield of the ... | 2001 | 11722901 |
| propionate formation by opitutus terrae in pure culture and in mixed culture with a hydrogenotrophic methanogen and implications for carbon fluxes in anoxic rice paddy soil. | propionate-forming bacteria seem to be abundant in anoxic rice paddy soil, but biogeochemical investigations show that propionate is not a correspondingly important intermediate in carbon flux in this system. mixed cultures of opitutus terrae strain pb90-1, a representative propionate-producing bacterium from rice paddy soil, and the hydrogenotrophic methanospirillum hungatei strain sk maintained hydrogen partial pressures similar to those in the soil. the associated shift away from propionate f ... | 2002 | 11916740 |
| 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 |
| isolation and characterization of a motile hydrogenotrophic methanogen from rice paddy field soil in japan. | a hydrogenotrophic motile methanogen was isolated from flooded japanese paddy field soil. anaerobic incubation of the paddy soil on h(2)-co(2) at 20 degrees c led to the enrichment of symmetrically curved motile autofluorescent rods. the methanogenic strain tm20-1 isolated from the culture was halotolerant and utilized h(2)-co(2), 2-propanol-co(2), or formate as a sole methanogenic substrate. based on the 16s rrna gene sequence similarity (94.8%) with methanospirillum hungateii, and on the physi ... | 2002 | 11959443 |