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1.
Two phylogenetically distinct marine strains producing transparent exopolymers (TEP), designated HTCC2155(T) and HTCC2160, were cultivated from Oregon coast seawater by dilution to extinction in a high throughput culturing format. When cultured in low-nutrient seawater media, these strains copiously produced Alcian Blue-stainable viscous TEP. Growing cells were attached to each other by the TEP in a three dimensional network. Polymerase chain reaction employing 16S rDNA primers specific for the novel isolates indicated that they are indigenous to the water column of the Atlantic and Pacific oceans. The abundance of the isolates as determined by 16S rRNA dot blots, however, indicated that they are less than 1% of the total bacterial community. In phylogenetic analyses, the strains consistently formed a new phylum-level lineage within the domain Bacteria, together with members of the candidate phylum VadinBE97, which consists of Victivallis, the first cultured genus in the candidate phylum, and 16S rRNA gene clones from DNA extracted from marine or anaerobic terrestrial habitats. Five putative subgroups were delineated within this phylum-level lineage, including a marine group and an anaerobic group. The isolates are Gram negative, strictly aerobic, chemoheterotrophic, and facultatively oligotrophic sphere-shaped bacteria. The DNA G+C content of strain HTCC2155(T) was 48.3 mol% and the genome size was 2.9 mb. It is proposed from these observations that the strains be placed into a new genus and a new species named Lentisphaera araneosa (type strain HTCC2155(T) = ATCC BAA-859(T) = KCTC 12141(T)) gen. nov., sp. nov., the cultured marine representative of the Lentisphaerae phyl. nov., and the phylum be divided into two novel orders named the Lentisphaerales ord. nov. and the Victivallales ord. nov.  相似文献   

2.
Spoilage in skipjack tuna (Katsuwonus pelamis) was studied under controlled conditions by incubating whole, fresh fish in seawater at 38 degrees C, the optimum temperature for histamine formation. Bacterial isolates were obtained from the loin tissue of a decomposing tuna containing 134 mg of histamine per 100 g and a total anaerobic count of 3.5 x 10(5)/g after incubation for 24 h. Over 92% of the 134 isolates obtained were facultatively or obligately anaerobic bacteria. Eighteen isolates produced histamine in culture media containing histidine, and these were identified as Clostridium perfringens, Enterobacter aerogenes, Klebsiella pneumoniae, Proteus mirabilis, and Vibrio alginolyticus. Histidine decarboxylase activity of several isolates was measured in a tuna broth medium and with resting cells suspended in a buffered histidine solution.  相似文献   

3.
Spoilage in skipjack tuna (Katsuwonus pelamis) was studied under controlled conditions by incubating whole, fresh fish in seawater at 38 degrees C, the optimum temperature for histamine formation. Bacterial isolates were obtained from the loin tissue of a decomposing tuna containing 134 mg of histamine per 100 g and a total anaerobic count of 3.5 x 10(5)/g after incubation for 24 h. Over 92% of the 134 isolates obtained were facultatively or obligately anaerobic bacteria. Eighteen isolates produced histamine in culture media containing histidine, and these were identified as Clostridium perfringens, Enterobacter aerogenes, Klebsiella pneumoniae, Proteus mirabilis, and Vibrio alginolyticus. Histidine decarboxylase activity of several isolates was measured in a tuna broth medium and with resting cells suspended in a buffered histidine solution.  相似文献   

4.
Five alginolytic, facultative anaerobic, non-motile bacteria were isolated from the gut of Japanese abalones (Haliotis discus discus, H. diversicolor diversicolor and H. diversicolor aquatilis). Phylogenetic analyses based on 16S rRNA gene and gap gene sequences indicated that these strains are closely related to V. halioticoli. DNA-DNA hybridizations, FAFLP fingerprintings, and phylogenies of gap and 16S rRNA gene sequences showed that the five strains represent two species different from all currently described vibrios. The names Vibrio neonatus sp. nov. (IAM 15060T = LMG 19973T = HDD3-1T; mol% G+C of DNA is 42.1-43.9), and Vibrio ezurae sp. nov. (IAM 15061T = LMG 19970T = HDS1-1T; mol% G+C of DNA is 43.6-44.8) are proposed to encompass these new taxa. The two new species can be differentiated from V. halioticoli on the basis of several features, including beta-galactosidase activity, assimilation of glycerol, D-mannose and D-gluconate.  相似文献   

5.
Three strains of maleate-fermenting anaerobic curved rods were isolated in pure culture from anaerobic freshwater mud samples. Among the isolates, strain CreMal1 was studied in detail. It was a mesophilic non-sporing gram-negative strict anaerobe, and grew not only on maleate but also on fumarate and l-malate, producing propionate and acetate stoichiometrically as end products. Succinate was an intermediate in the degradation of maleate. Nitrate, sulfate, and other sulfur compounds were not utilized as electron acceptors. It had 61 mol% guanine-plus-cytosine content, but possessed a single polar flagellum and did not utilize carbohydrates and lactate, unlike the genus Selenomonas. Therefore, strain CreMal1 is described as a member of Propionivibrio dicarboxylicus gen. nov., sp. nov., in the family Bacteroidaceae. Strain CreMal1 was deposited as type strain in the Japan Collection of Microorganisms and in Deutsche Sammlung von Mikroorganismen.Dedicated to Professor Dr. Norbert Pfennig on the occasion of his 65th birthday  相似文献   

6.
Five strains of rod-shaped, Gram-negative, non-sporing, strictly anaerobic bacteria were isolated from limnic and marine mud samples with gallic acid or phloroglucinol as sole substrate. All strains grew in defined mineral media without any growth factors; marine isolates required salt concentrations higher than 1% for growth, two freshwater strains only thrived in freshwater medium. Gallic acid, pyrogallol, 2,4,6-trihydroxybenzoic acid, and phloroglucinol were the only substrates utilized and were fermented stoichiometrically to 3 mol acetate (and 1 mol CO2) per mol with a growth yield of 10g cell dry weight per mol of substrate. Neither sulfate, sulfur, nor nitrate were reduced. The DNA base ratio was 51.8% guanine plus cytosine. A marine isolate, Ma Gal 2, is described as type strain of a new genus and species, Pelobacter acidigallici gen. nov. sp. nov., in the family Bacteroidaceae. In coculture with Acetobacterium woodii, the new isolates converted also syringic acid completely to acetate. Cocultures with Methanosarcina barkeri converted the respective substrates completely to methane and carbon dioxide.  相似文献   

7.
A novel strain, designated as BL-10(T), was characterized using a polyphasic approach after isolation from groundwater contaminated by a mixture of chlorosolvents that included 1,1,2-trichloroethane, 1,2-dichloroethane, and vinyl chloride. Stain BL-10(T) is a facultatively anaerobic bacterium able to ferment glucose to form propionate, acetate, formate, lactate, and succinate. Fermentation occurred in the presence of 1,2-dichloroethane and 1,1,2-trichloroethane at concentrations to at least 9.8 and 5.9 mM, respectively. Cells are Gram-positive, rod-shaped, non-motile, and do not form spores. Oxidase and catalase are not produced and nitrate reduction did not occur in PYG medium. Menaquinone MK-9 is the predominant respiratory quinone and meso-diaminopimelic acid is present in the cell wall peptidoglycan layer. Major cellular fatty acids are C(15:0), iso C(16:0), and anteiso C(15:0). Genomic DNA G + C content is 69.9 mol%. Phylogenetic analysis based on 16S rRNA gene sequence comparisons showed strain BL-10(T) to fall within the radiation of genera Propionicimonas and Micropruina. On the basis of the results obtained in this study, it is proposed that strain BL-10(T) should be classified as a novel taxon, for which the name Propionicicella superfundia gen. nov., sp. nov. is proposed. The type strain of Propionicicella superfundia is BL-10(T) (=ATCC BAA-1218(T), =LMG 23096(T)).  相似文献   

8.
Heterofermentative, lactic acid-producing, gram-positive, motile bacteria were isolated from the waters of Ace Lake, Antarctica. All strains produced virtually only l(+)lactic acid from d(+)glucose. d(–)ribose was fermented to lactic, acetic, and formic acids, and ethanol. Cell walls contained meso-diaminopimaleic acid. The strains did not grow at 30°C and were psychrotrophic. Whole cells contained 18:1cis 9 as a major component of their fatty acids. At 20°C, the strains grew better anaerobically than aerobically and all strains lacked catalase, oxidase and respiratory lipoquinones. DNA that coded for most of the 16S rRNA gene of one of the strains was amplified by the polymerase chain reaction and sequenced. The strain was phylogenetically most closely related to Carnobacterium mobile (Knuc=0.0214). The isolates separated into two phenotypes. DNA/DNA homology studies determined on a representative from each phenotype showed low homology between the phenotypes (38±8%), and with Carnobacterium mobile (26±2%, 34±2%). Carnobacterium funditum sp. nov. produced acid from mannitol, trehalose, but not amygdalin. The G+C content of the DNA was 32–34%, and the Type strain is DSM 5970 (=ACAM 312). Carnobacterium alterfunditum sp. nov. produced acid weakly from amygdalin but not from mannitol or trehalose. The G+C content was 33–34%, and the Type strain is DSM 5972 (=ACAM 313).  相似文献   

9.
Two new species of aerobic, gram-negative, peritrichously flagellated or nonmotile marine bacteria usually forming star-shaped aggregates were isolated from northeastern Atlantic Ocean bottom sediments. These organisms resembled eight star-shaped-aggregate-forming bacterial species from the Baltic Sea originally ascribed to the genus Agrobacterium but not included on the Approved Lists of Bacterial Names because of their questionable relationships to true agrobacteria. These two sets of star-shaped-aggregate-forming bacteria were compared by means of phenotypic data, DNA base compositions, DNA-DNA relatedness, and one-dimensional electrophoretic analysis of low-molecular-weight RNAs (5S rRNA and tRNA). According to the results of genotyping, the northeastern Atlantic Ocean isolates and three of the Baltic Sea species formed a group of closely related bacteria that could not be excluded from the genus Agrobacterium with certainty. Until more genotypic data are available, these five marine species are regarded as a distinct subdivision of the genus Agrobacterium consisting of Agrobacterium atlanticum sp. nov. (type strain, 1480T = DSM 5823T), A. meteori sp. nov. (type strain, 1513T = DSM 5824T), A. ferrugineum sp. nov. nom. rev. emend. (type strain, ATCC 25652T), A. gelatinovorum sp. nov. nom. rev. emend. (type strain, ATCC 25655T), and A. stellulatum sp. nov. nom. rev. emend. (type strain, ATCC 15215T). "A. aggregatum" proved to be a later subjective synonym of A. stellulatum, which had priority. The remaining four Baltic Sea species, "A. agile," "A. kieliense," "A. luteum," and "A. sanguineum," could not be placed in the new subdivision of Agrobacterium.  相似文献   

10.
New alkaliphilic, saccharolytic, rod-shaped, gram-positive bacteria resistant to heating and drying and phylogenetically affiliated to the Bacillus lineage were isolated under strictly anaerobic conditions from sediments of the alkaline and highly mineralized Lake Magadi. Strain Z-7792 forms endospores; in strain Z-7984, endospore formation was not revealed. The strains are capable of both anaerobic growth (at the expense of fermentation of glucose and certain mono- and disaccharides with the formation of formate, ethanol, and acetate) and aerobic growth. Among polysaccharides, the strains hydrolyze starch, glycogen, and xylan. Yeast extract or methionine are required for growth. The strains are strict alkaliphiles exhibiting obligate requirement for Na+ and carbonate ions but not for Cl- ion. Growth occurs at a total mineralization as high as 3.3-3.6 M Na+, with an optimum at 1-1.7 M Na+. Strain Z-7792 is an obligate alkaliphile with a pH growth range of 8.5-11.5 and an optimum of 9.5-9.7. Strain Z-7984 grows in a pH range of 7.0-10.5 with an optimum at 8.0-9.5. Both strains are mesophiles having a growth optimum at 37-38 degrees C. They belong to bacilli with a low G + C content. The G + C contents of the DNA of strains Z-7792 and Z-7984 are 39.2 and 41.5 mol%, respectively. These isolates of facultatively anaerobic, strictly alkaliphilic, Na(+)-dependent bacilli can be considered representatives of the ecological group adapted to the life at drying-up shoars of soda lakes. Because of their independence of NaCl and lack of obligate dependence on sodium carbonates, the isolates are to be assigned to athalassophilic organisms. According to their physiological and phylogenetic characteristics, they taxonomically belong to group 1 of the species of bacilli, occupying a position intermediate between the genera Amphibacillus and Gracilibacillus. The isolates are described as new species of Amphibacillus: A. fermentum (type strain, Z-7984T) and A. tropicus (type strain, Z-7792T).  相似文献   

11.
Forty-six strains of acetic acid bacteria newly isolated from flowers, fruits, and fermented foods collected in Indonesia were taxonomically studied. They were Gram-negative rods, produced acetic acid from ethanol, oxidized acetate and lactate to CO(2) and H(2)O, and had Q-9 as the major ubiquinone system. On the basis of DNA-DNA similarity, all strains studied, including type strains and reference strains of the genus Acetobacter, were separated into eleven groups (Groups I to XI). Of the 46 isolates, two isolates were included in Group II and identified as Acetobacter pasteurianus, five in Group IV as A. orleanensis, 16 in Group V as A. lovaniensis, five in Group VII as A. indonesiensis, and three in Group VIII as A. tropicalis. The remaining 15 isolates constituted three new groups based on DNA-DNA similarity; four isolates were included in Group IX, two in Group X, and nine in Group XI. No isolates were identified as A. aceti (Group I), A. peroxydans (Group III), and A. estunensis (Group VI). Phylogenetic analysis based on 16S rDNA sequences of representative strains of the Groups indicated belonging to the strains of the genus Acetobacter. On the basis of DNA base composition, DNA-DNA similarity, and 16S rDNA sequences, three new species of the genus Acetobacter are proposed: Acetobacter syzygii sp. nov. for Group IX, Acetobacter cibinongensis sp. nov. for Group X, and Acetobacter orientalis sp. nov. for Group XI. The distribution of Acetobacter strains in Indonesia is discussed in light of isolation sources.  相似文献   

12.
Four strains of obligately heterotrophic bacteria isolated from the oxygen-sulfide interface of the Black Sea are characterized. The bacteria are aerobic, Gram-negative, with lemon-like, nonmotile cells. Bacteriochlorophyll a is not detected. They are mesophilic and neutrophilic with a temperature range of 8–35 °C (optimum 25) and pH range of 6.5–8.5 (optimum 7.8). Their growth is NaCl dependent within a range of 5 and 60 (optimum 20) g l−1. They are able to oxidize thiosulfate, sulfide and elemental sulfur to sulfate and to use metabolic energy from these reactions (lithoheterotrophy). According to the level of DNA reassociation of more than 40%, all isolates represent a single generic group. The G+C content of the DNA was in the range of 67.5–69.2 mol%. According to phylogenetic analysis, the new isolates form a separate branch in the alpha-3 subdivision of the Proteobacteria together with two undescribed marine bacterial strains. On the basis of phenotypical and genomic properties, the new isolates are described as a new genus and species Citreicella thiooxidans gen. nov., sp. nov. The type strain is CHLG 1T (=DSM 10146, UNIQEM U 228).  相似文献   

13.
Phylogenetic studies were performed on some Gram-positive catalase-negative cocci from human clinical sources of uncertain taxonomic position. 16S rRNA sequence analysis demonstrated that the isolates represent a hitherto unknown line of descent within the low G+C Gram-positive bacteria for which the name Globicatella sanguis gen.nov., sp.nov. is proposed.  相似文献   

14.
Storage of swine manure is associated with the microbiological production of a variety of odorous compounds, including ammonia, organic acids, and alcohols, phenolics, and sulfides. Until recently, little was known about the microorganisms responsible for their production. Results from our laboratory have demonstrated that the predominant microbial populations of stored swine manure are anaerobic, low (G + C), Gram-positive bacteria. However, studies on pure cultures isolated from manure have found few microorganisms that produce appreciable ammonia concentrations. Therefore, selective and enrichment techniques were employed to isolate ammonia-producing bacteria from stored swine manure by using media containing peptone and amino acids as carbon and energy sources. We now report on the isolation of 40 bacterial cultures, a number of which are capable of producing at least 40 mM ammonia in peptone-amino acid medium, concentrations similar to those produced by hyper-ammonia producing (HAP) bacteria isolated from the rumen of cattle. The manure HAP isolates are phylogenetically distinct from the ruminal isolates and may prove to be intimately involved in the production of ammonia during storage of swine manure.  相似文献   

15.
16.
Phylogenetic studies were performed on some Gram-positive catalase-negative cocci from human clinical sources of uncertain taxonomic position. 16S rRNA sequence analysis demonstrated that the isolates represent a hitherto unknown line of descent within the low G + C Gram-positive bacteria for which the name Globicatella sanguis gen.nov., sp.nov. is proposed.  相似文献   

17.
A taxonomic study was carried out on Chj404T, a bacterial strain isolated from a soil sample collected in an industrial stream near the Chung-Ju industrial complex in Korea. The strain was a gram-negative, aerobic, short rod to coccus-shaped bacterium. It grew well on nutrient agar medium and utilized a broad spectrum of carbon sources. The G+C content of the DNA was 67.4 mol% and the major composition of ubiquinone was Q-10. The major fatty acid was C18:1. Comparative 16S rDNA studies showed a clear affiliation of this bacterium to alpha-Proteobacteria. Comparison of phylogenetic data indicated that it was most closely related to Prosthecomicrobium pneumaticum (92.7% similarity in 16S rDNA sequence). Since strain Chj404 is clearly distinct from closely related species, we propose the name Kaistia adipata gen. nov., sp. nov. for this strain Chj404T (=IAM 15023T=KCTC 12095T).  相似文献   

18.
Two strains of aerobic acidophilic chemoorganotrophic bacteria designed strains AP8(T) and AP9 were isolated from acid mine drainage and acidic soil, respectively. These isolates were gram-negative, nonmotile cocci and coccobacilli measuring 0.5-0.8 μm in diameter. Cells were capsulated. Colonies on solid media were pink colored. The pH range for growth was 3.0-6.0 (optimum pH 4.5). Sugars, gluconate, and some amino acids were good carbon and energy sources for growth. The main components of cellular fatty acids were C(15:0) iso and C(16:1) ω7c. Menaquinone-8 was the major quinone. The G+C content of genomic DNA was 59.5%. Both strains had identical sequences of 16S rRNA genes that were most closely related to that of the type strain of Acidobacterium capsulatum (96% similarity). There were major differences between the isolates and A. capsulatum in cell morphology, carbon nutrition, and fatty acid profiles. Based on these phylogenetic and phenotypic data, we propose the name Acidipila rosea gen. nov., sp. nov. to accommodate the novel isolates. The type strain is AP8(T) (NBRC 107607(T), KCTC 23427(T)).  相似文献   

19.
AIM: To study the diversity of commensal Escherichia coli populations shed in faeces of cattle fed on different diets. METHODS AND RESULTS: Thirty Brahman-cross steers were initially fed a high grain (80%) diet and then randomly allocated into three dietary treatment groups, fed 80% grain, roughage, or roughage + 50% molasses. Up to eight different E. coli isolates were selected from primary isolation plates of faecal samples from each animal. Fifty-two distinct serotypes, including nine different VTEC strains, were identified from a total of 474 E. coli isolates. Cattle fed a roughage + molasses diet had greater serotype diversity (30 serotypes identified) than cattle fed roughage or grain (21 and 17 serotypes identified respectively). Cluster analysis showed that serotypes isolated from cattle fed roughage and roughage + molasses diets were more closely associated than serotypes isolated from cattle fed grain. Resistance to one or more of 11 antimicrobial agents was detected among isolates from 20 different serotypes. Whilst only 2.3% of E. coli isolates produced enterohaemolysin, 25% were found to produce alpha-haemolysin. CONCLUSIONS: Diverse non-VTEC populations of E. coli serotypes are shed in cattle faeces and diet may affect population diversity. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provides new information on the serotype diversity and phenotypic traits of predominant E. coli populations in cattle faeces, which could be sources of environmental contamination.  相似文献   

20.
Five strains of acetogenic bacteria were isolated by selective enrichment from the rumen of a mature Hereford crossbred steer fed a typical high forage diet. Suspensions of rumen bacteria, prepared from contents collected 7 h postfeeding, blended and strained through cheesecloth, were incubated in a minimal medium containing 10% clarified rumen fluid under either H2:CO2 (80:20) or N2:CO2 (80:20) headspace atmosphere. The selection criterion was an increment of acetate in the enrichments incubated under H2:CO2. Periodically, the enrichment broths were plated onto agar media and presumed acetogenic bacteria subsequently were screened for acetate production. Selected acetogenic bacteria utilized a pressurized atmosphere of H2:CO2 to form acetate in quantities 2 to 8-fold higher than when grown under N2:CO2. All presumptive acetogenic isolates were derived from either the 10-7 or 10-8 dilutions of rumen contents. All 5 strains were Gram-positive rods, and all utilized formate, glucose and CO. One strain required, and all were stimulated by, rumen fluid. No spores were observed with phase-contast microscopy and two strains were motile. No methane was detected in the headspace of pure cultures grown under either gas phase. The isolation of these bacteria indicates that acetogenic bacteria are inhabitants of the rumen of the bovine fed a typical diet and suggests that they may be participants in the utilization of hydrogen in the rumen ecosystem. Strain 139B (= ATCC 43876) is named Acetitomaculum ruminis gen. nov., sp. nov. and is the type strain of this new species. Portions of this work were presented previously (Greening RC, Leedle JAZ (1987) Abstr Annu Meet Am Soc Microbiol I 131, pp 194)  相似文献   

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