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1.
Alicycliphilus denitrificans strain BC and A. denitrificans strain K601(T) degrade cyclic hydrocarbons. These strains have been isolated from a mixture of wastewater treatment plant material and benzene-polluted soil and from a wastewater treatment plant, respectively, suggesting their role in bioremediation of soil and water. Although the strains are phylogenetically closely related, there are some clear physiological differences. The hydrocarbon cyclohexanol, for example, can be degraded by strain K601(T) but not by strain BC. Furthermore, both strains can use nitrate and oxygen as an electron acceptor, but only strain BC can use chlorate as electron acceptor. To better understand the nitrate and chlorate reduction mechanisms coupled to the oxidation of cyclic compounds, the genomes of A. denitrificans strains BC and K601(T) were sequenced. Here, we report the complete genome sequences of A. denitrificans strains BC and K601(T).  相似文献   

2.
A bacterium, strain BC, was isolated from a benzene-degrading chlorate-reducing enrichment culture. Strain BC degrades benzene in conjunction with chlorate reduction. Cells of strain BC are short rods that are 0.6 μm wide and 1 to 2 μm long, are motile, and stain gram negative. Strain BC grows on benzene and some other aromatic compounds with oxygen or in the absence of oxygen with chlorate as the electron acceptor. Strain BC is a denitrifying bacterium, but it is not able to grow on benzene with nitrate. The closest cultured relative is Alicycliphilus denitrificans type strain K601, a cyclohexanol-degrading nitrate-reducing betaproteobacterium. Chlorate reductase (0.4 U/mg protein) and chlorite dismutase (5.7 U/mg protein) activities in cell extracts of strain BC were determined. Gene sequences encoding a known chlorite dismutase (cld) were not detected in strain BC by using the PCR primers described in previous studies. As physiological and biochemical data indicated that there was oxygenation of benzene during growth with chlorate, a strategy was developed to detect genes encoding monooxygenase and dioxygenase enzymes potentially involved in benzene degradation in strain BC. Using primer sets designed to amplify members of distinct evolutionary branches in the catabolic families involved in benzene biodegradation, two oxygenase genes putatively encoding the enzymes performing the initial successive monooxygenations (BC-BMOa) and the cleavage of catechol (BC-C23O) were detected. Our findings suggest that oxygen formed by dismutation of chlorite can be used to attack organic molecules by means of oxygenases, as exemplified with benzene. Thus, aerobic pathways can be employed under conditions in which no external oxygen is supplied.  相似文献   

3.
Microbial (per)chlorate reduction is a unique process in which molecular oxygen is formed during the dismutation of chlorite. The oxygen thus formed may be used to degrade hydrocarbons by means of oxygenases under seemingly anoxic conditions. Up to now, no bacterium has been described that grows on aliphatic hydrocarbons with chlorate. Here, we report that Pseudomonas chloritidismutans AW-1T grows on n-alkanes (ranging from C7 until C12) with chlorate as electron acceptor. Strain AW-1T also grows on the intermediates of the presumed n-alkane degradation pathway. The specific growth rates on n-decane and chlorate and n-decane and oxygen were 0.5 ± 0.1 and 0.4 ± 0.02 day−1, respectively. The key enzymes chlorate reductase and chlorite dismutase were assayed and found to be present. The oxygen-dependent alkane oxidation was demonstrated in whole-cell suspensions. The strain degrades n-alkanes with oxygen and chlorate but not with nitrate, thus suggesting that the strain employs oxygenase-dependent pathways for the breakdown of n-alkanes.  相似文献   

4.
5.
An endophytic actinobacterial strain was isolated from a yellowwood tree growing on the slope of Devil’s Peak, Cape Town, South Africa. Analysis of the 16S rRNA gene showed that the strain belongs to the genus Kribbella. Phylogenetic analyses using the 16S rRNA gene and multilocus sequence analysis using the concatenated gene sequences of the gyrB, rpoB, relA, recA and atpD genes showed that strain YPL1T is closely related to the type strains of Kribbella karoonensis and Kribbella shirazensis. DDH experiments showed that strain YPL1T is a distinct genomic species from its close phylogenetic relative, K. karoonensis Q41T. Physiological comparisons further showed that strain YPL1T is phenotypically distinct from the type strains of Kribbella jejuensis, Kribbella aluminosa, K. karoonensis, K. shirazensis and Kribbella swartbergensis. Strain YPL1T is thus presented as the type strain of a novel species, for which the name Kribbella podocarpi sp. nov. (= DSM 29424T = NRRL B-65063T), is proposed.  相似文献   

6.
The functions of specific microorganisms in a microbial community were investigated during the composting process. Cerasibacillus quisquiliarum strain BLxT and Bacillus thermoamylovorans strain BTa were isolated and characterized in our previous studies based on their dominance in the composting system. Strain BLxT degrades gelatin, while strain BTa degrades starch. We hypothesized that these strains play roles in gelatinase and amylase production, respectively. The relationship between changes in the abundance ratios of each strain and those of each enzyme activity during the composting process was examined to address this hypothesis. The increase in gelatinase activity in the compost followed a dramatic increase in the abundance ratio of strain BLxT. Zymograph analysis demonstrated that the pattern of active gelatinase bands from strain BLxT was similar to that from the compost. Gelatinases from both BLxT and compost were partially purified and compared. Homologous N-terminal amino acid sequences were found in one of the gelatinases from strain BLxT and that of compost. These results indicate strain BLxT produces gelatinases during the composting process. Meanwhile, the increase in the abundance ratio of strain BTa was not concurrent with that of amylase activity in the compost. Moreover, the amylase activity pattern of strain BTa on the zymogram was different from that of the compost sample. These results imply that strain BTa may not produce amylases during the composting process. To our knowledge, this is the first report demonstrating that the function of a specific microorganism is directly linked to a function in the community, as determined by culture-independent and enzyme-level approaches.  相似文献   

7.
Rhodopirellula baltica SH1T is a marine planctomycete with 7,325 genes in its genome. Ten strains of the genus Rhodopirellula were studied in whole genome microarray experiments to assess the extent of their genetic relatedness to R. baltica SH1T. DNA of strains which were previously affiliated with the species R. baltica (OTU A) hybridized with 3,645–5,728 genes of the type strain on the microarray. Strains SH398 and 6C (OTU B), representing a closely related species with an average nucleotide identity of 88 %, showed less hybridization signals: 1,816 and 3,302 genes gave a hybridization signal, respectively. Comparative genomics of eight permanent draft genomes revealed the presence of over 4,000 proteins common in R. baltica SH1T and strains of OTU A or B. The genus Rhodopirellula is characterized by large genomes, with over 7,000 genes per genome and a core genome of around 3000 genes. Individual Rhodopirellula strains have a large portion of strain-specific genes.  相似文献   

8.
The complete genome sequence of Bacillus amyloliquefaciens type strain DSM7T is presented. A comparative analysis between the genome sequences of the plant associated strain FZB42 (Chen et al., 2007) with the genome of B. amyloliquefaciens DSM7T revealed obvious differences in the variable part of the genomes, whilst the core genomes were found to be very similar. The strains FZB42 and DSM7T have in common 3345 genes (CDS) in their core genomes; whilst 547 and 344 CDS were found to be unique in DSM7T and FZB42, respectively. The core genome shared by both strains exhibited 97.89% identity on amino acid level. The number of genes representing the core genome of the strains FZB42, DSM7T, and Bacillus subtilis DSM10T was calculated as being 3098 and their identity was 92.25%. The 3,980,199 bp genome of DSM7T contains numerous genomic islands (GI) detected by different methods. Many of them were located in vicinity of tRNA, glnA, and glmS gene copies. In contrast to FZB42, but similar to B. subtilis DSM10T, the GI were enriched in prophage sequences and often harbored transposases, integrases and recombinases. Compared to FZB42, B. amyloliquefaciens DSM7T possessed a reduced potential to non-ribosomally synthesize secondary metabolites with antibacterial and/or antifungal action. B. amyloliquefaciens DSM7T did not produce the polyketides difficidin and macrolactin and was impaired in its ability to produce lipopeptides other than surfactin. Differences established within the variable part of the genomes, justify our proposal to discriminate the plant-associated ecotype represented by FZB42 from the group of type strain related B. amyloliquefaciens soil bacteria.  相似文献   

9.
Members of the family Clostridiaceae within phylum Firmicutes are ubiquitous in various iron-reducing environments. However, genomic data on iron-reducing bacteria of the family Clostridiaceae, particularly regarding their environmental distribution, are limited. Here, we report the analysis and comparison of the genomic properties of Geosporobacter ferrireducens IRF9, a strict anaerobe that ferments sugars and degrades toluene under iron-reducing conditions, with those of the closely related species, Geosporobacter subterraneus DSM 17957. Putative alkyl succinate synthase-encoding genes were observed in the genome of strain IRF9 instead of the typical benzyl succinate synthase-encoding genes. Canonical genes associated with iron reduction were not observed in either genome. The genomes of strains IRF9 and DMS 17957 harbored genes for acetogenesis, that encode two types of Rnf complexes mediating the translocation of H+ and Na+ ions, respectively. Strain IRF9 harbored two different types of ATPases (Na+-dependent F-type ATPase and H+-dependent V-type ATPase), which enable full exploitation of ion gradients. The versatile energy conservation potential of strain IRF9 promotes its survival in various environmental conditions.  相似文献   

10.
Twelve Acetobacter pasteurianus-related strains with publicly available genomes in GenBank shared high 16S rRNA gene sequence similarity (>99.59%), but average nucleotide identity (ANI) and in silico DNA-DNA hybridization (DDH) values and multilocus sequence- and genome-based relatedness analyses suggested that they were divided into four different phylogenetic lineages. Relatedness analyses based on multilocus sequences, 1,194 core genes and whole-cell MALDI-TOF profiles supported that strains LMG 1590T and LMG 1591 (previously classified as the type strains of A. pasteurianus subsp. ascendens and paradoxus, respectively) and strain SLV-7T do not belong to A. pasteurianus. Strain SLV-7T, isolated from Korean traditional vinegar, shared low ANI (<91.0%) and in silico DDH (44.2%) values with all other Acetobacter type strains analyzed in this study, indicating that strain SLV-7T represents a new Acetobacter species. The phenotypic and chemotaxonomic analyses confirmed these results and therefore a new species named Acetobacter oryzifermentans sp. nov. is proposed with SLV-7T (= KACC 19301T = JCM 31096T) as the type strain. Strains LMG 1590T and LMG 1591 shared high ANI (99.4%) and in silico DDH (96.0%) values between them, but shared low ANI (<92.3%) and in silico DDH (<49.0%) values with other type strains analyzed in this study, indicating that strains LMG 1590T and LMG 1591 should be reclassified into a new single species that should be named Acetobacter ascendens sp. nov., comb. nov., with LMD 51.1T (= LMG 1590T = NCCB 51001T) as its type strain.  相似文献   

11.
A thermophilic, anaerobic, chemolithoautotrophic bacterium (strain SU872T) was isolated from a shallow-sea hydrothermal vent at Kunashir Island. The cells were motile, gram-negative, oval or rodshaped 0.5?0.6 μm thick and 1.5?2.0 μm long, occurring singly or in pairs. Strain SU872T grew at 50 to 79°C (optimum at 74°C), pH from 5.0 to 8.0 (optimum at 6.7?7.0), and NaCl concentration of 1.5–4.5%. Strain SU872T was able to grow by disproportionation of elemental sulfur, thiosulfate, or sulfite, with CO2/HCO3? as the sole carbon source. Growth was enhanced in the presence of ferrihydrite (poorly crystalline Fe(III) oxide) as as a sulfide-scavenging agent. Sulfate was not used as an electron acceptor. Growth also occurred with elemental sulfur, thiosulfate, or sulfite (but not sulfide) as electron donors and nitrate as an electron acceptor, with production of sulfate and ammonium. Analysis of the 16S rRNA gene sequence revealed 97.8% similarity between strain SU872T and the type strain Thermosulfurimonas dismutans S95T (phylum Thermodesulfobacteria). According to the results of DNA–DNA hybridization, the similarity of genomic DNA of the strains SU872T and T. dismutans S95T was 48%. Based on its phenotypic characteristics and the results of phylogenetic analysis, it is proposed to assign the isolate to a new species of the genus Thermosulfurimonas,—Thermosulfurimonas marina sp. nov., with the type strain SU872T (=DSM 104922T, =VKM B-3177T, =UNIQEM SU872T).  相似文献   

12.
During a study of the diversity and phylogeny of rhizobia isolated from root nodules of Oxytropis ochrocephala grown in the northwest of China, four strains were classified in the genus Rhizobium on the basis of their 16S rRNA gene sequences. These strains have identical 16S rRNA gene sequences, which showed a mean similarity of 94.4 % with the most closely related species, Rhizobium oryzae. Analysis of recA and glnA sequences showed that these strains have less than 88.1 and 88.7 % similarity with the defined species of Rhizobium, respectively. The genetic diversity revealed by ERIC-PCR fingerprinting indicated that the isolates correspond to different strains. Strain CCNWQLS01T contains Q-10 as the predominant ubiquinone. The major fatty acids were identified as feature 8 (C18: 1ω7c and/or C18: 1ω6c; 67.2 %). Therefore, a novel species Rhizobium qilianshanense sp. nov. is proposed, and CCNWQLS01T (= ACCC 05747T = JCM 18337T) is designated as the type strain.  相似文献   

13.
Strain Marseille-P1302 was isolated from the stool of a 2-year-old Nigerian boy suffering from Kwashiorkor, a form of severe acute malnutrition. The strain grows in aerobic atmosphere and bacterial cells are Gram-positive cocci ranging in diameter from 0.8 to 1 μm. Among species with standing in nomenclature, strain Marseille-P1302 exhibited a highest 16S rRNA sequence similarity of 94.97% with Brevilactibacter flavus strain VG341T, but was phylogenetically-closest to Brevilactibacter sinopodophylli strains KCTC 33808T. The draft genome of strain Marseille-P1302 was 2,934,258-bp-long with a 70.38% G + C content, and contained 2704 protein-coding genes and 55 RNAs that included 9 rRNA genes. On the basis of these data, we propose the creation of the new genus Nigeribacterium gen. nov., with strain Marseille-P1302T (= CSUR P1302 = DSM 29084) being the type strain of the new species Nigeribacterium. massiliense gen. nov., sp. nov.  相似文献   

14.
Phaseolus vulgaris is a legume indigenous to America which is nodulated by strains of genus Rhizobium in Croatia. Four of these strains, 13TT, 9T, 18TT and 8Z are phylogenetically close to the species from the Rhizobium leguminosarum phylogenetic complex in the 16S rRNA gene analysis. The results of both the analyses of the concatenated recA and atpD genes and whole genomes revealed that the strains 13TT and 9T clustered with Rhizobium sophoriradicis CCBAU 03470T and the strains 18TT and 8Z with Rhizobium ecuadorense CNPSO 671T. Whole genome average nucleotide identity blast (ANIb) and dDDH values between the strains 13TT and the type strain of R. sophoriradicis and between the strains 18TT and the type strain of R. ecuadorense were lower than 95% and 70%, respectively, which are the threshold values recommended for bacterial species differentiation. These results combined with those of chemotaxonomic and phenotypic analyses support the affiliation of these strains to two novel species within the genus Rhizobium for which we propose the names Rhizobium croatiense sp. nov. 13TT (=LMG 32397T, = HAMBI 3740T) as type strain and Rhizobium redzepovicii sp. nov. 18TT (=LMG 32398T, = HAMBI 3741T) as type strain.  相似文献   

15.
Four strains representing three novel anamorphic yeast species were isolated from the external surface of sugarcane leaves (DMKU-RK254T), corn leaves (DMKU-RK548T), bean leaves (K129) in Thailand and hengchun pencilwood leaves (TrB1-1T) in Taiwan. On the basis of morphological, biochemical, physiological and chemotaxonomic characteristics, the sequence analysis of the D1/D2 region of the large subunit (LSU) rRNA gene, the internal transcribed spacer (ITS) region, the actin gene (ACT1) and the elongation factor 2 gene (EF2), the four strains were determined to represent novel Yamadazyma species although formation of ascospores was not observed. Strain DMKU-RK254T was determined to be related to Candida diddensiae, Candida naeodendra and Candida kanchanaburiensis but with 1.8, 1.8 and 2.0 % nucleotide substitutions in the D1/D2 region of the LSU rRNA gene, respectively. It was assigned to Yamadazyma siamensis sp. nov. (type strain DMKU-RK254T = BCC 50730T = NBRC 108901T = CBS 12573T). The sequences of the D1/D2 region of the LSU rRNA gene, the ITS region, ACT1 gene and EF2 gene of two strains (DMKU-RK548T and K129) were identical but differed from that of strain TrB1-1T by 0.6, 1.0, 3.3 and 5.9 % nucleotide substitutions, respectively. Therefore, the two strains (DMKU-RK548T and K129) and strain TrB1-1T were assigned to be two separate species. The closest species in terms of pairwise sequences similarity of the D1/D2 region to the two novel species was Yamadazyma philogaea but with 1.1–1.7 % nucleotide substitutions. The two strains (DMKU-RK548T and K129) were assigned to Yamadazyma phyllophila sp. nov. (type strain DMKU-RK548T = BCC 50736T = NBRC 108906T = CBS 12572T) and the strain TrB1-1T was named Yamadazyma paraphyllophila sp. nov. (type strain TrB1-1T = BCRC 23030T = CCTCC AY 204005T = CBS 9928T).  相似文献   

16.
Strain JC90T was isolated from a soda lake in Lonar, India. Strain JC90T maintains its external pH to 8.5 and participates in halite formation. Based on 16S rRNA gene sequence similarity studies, strain JC90T was found to belong to the genus Salinicoccus and is most closely related to “Salinicoccus kekensis” K164T (99.3 %), Salinicoccus alkaliphilus T8T (98.4 %) and other members of the genus Salinicoccus (<96.5 %). However Strain JC90T is <36 % related (based on DNA–DNA hybridization) with the type strains of “S. kekensis” K164T and S. alkaliphilus T8T. The DNA G+C content of strain JC90T was determined to be 46 mol %. The cell-wall amino acids were identified as lysine and glycine. Polar lipids were found to include diphosphatidylglycerol, phosphatidylglycerol, phosphatidyl ethanolamine, an unidentified glycolipid and unidentified lipids (L1,2). Major hopanoids of strain JC90T were determined to be bacterial hopane derivatives (BHD1,2), diplopterol, diploptene and two unidentified hopanoids (UH1,2). The predominant isoprenoid quinone was identified as menaquinone (MK-6). Anteiso-C15:0 was determined to be the predominant fatty acid and significant proportions of iso-C14:0, C14:0, iso-C15:0, C16:0, iso-C16:0, iso-C17:0, anteiso-C17:0 and C18:02OH were also detected. The results of physiological and biochemical tests support the molecular evidence and allowed a clear phenotypic differentiation of strain JC90T from all other members of the genus Salinicoccus. Strain JC90T is therefore considered to represent a novel species, for which the name Salinicoccus halitifaciens sp. nov. is proposed. The type strain is JC90T (=KCTC 13894T =DSM 25286T).  相似文献   

17.
Two heterotrophic bacteroidetes strains were isolated as satellites from autotrophic enrichments inoculated with samples from hypersaline soda lakes in southwestern Siberia. Strain Z-1702T is an obligate anaerobic fermentative saccharolytic bacterium from an iron-reducing enrichment culture, while Ca. Cyclonatronum proteinivorum OmegaT is an obligate aerobic proteolytic microorganism from a cyanobacterial enrichment. Cells of isolated bacteria are characterized by highly variable morphology. Both strains are chloride-independent moderate salt-tolerant obligate alkaliphiles and mesophiles. Strain Z-1702T ferments glucose, maltose, fructose, mannose, sorbose, galactose, cellobiose, N-acetyl-glucosamine and alpha-glucans, including starch, glycogen, dextrin, and pullulan. Strain OmegaT is strictly proteolytic utilizing a range of proteins and peptones. The main polar lipid fatty acid in both strains is iso-C15:0, while other major components are various C16 and C17 isomers. According to pairwise sequence alignments using BLAST Gracilimonas was the nearest cultured relative to both strains (<90% of 16S rRNA gene sequence identity). Phylogenetic analysis placed strain Z-1702T and strain OmegaT as two different genera in a deep-branching clade of the new family level within the order Balneolales with genus. Based on physiological characteristics and phylogenetic position of strain Z-1702T it was proposed to represent a novel genus and species Natronogracilivirga saccharolityca gen. nov., sp. nov. (= DSMZ 109061T =JCM 32930T =VKM B 3262T). Furthermore, phylogenetic and phenotypic parameters of N. saccharolityca and C. proteinivorum gen. nov., sp. nov., strain OmegaT (=JCM 31662T, =UNIQEM U979T), make it possible to include them into a new family with a proposed designation Cyclonatronaceae fam. nov..  相似文献   

18.
19.
Exploration of unexplored habitats for novel actinobacteria with high bioactivity potential holds great promise in the search for novel entities. During the course of isolation of actinobacteria from desert soils, four actinobacteria, designated as 5K548T, 7K502T, 16K309T and 16K404T, were isolated from the Karakum Desert and their bioactivity potential as well as taxonomic provenances were revealed by comprehensive genome analyses. Pairwise sequence analyses of the 16S rRNA genes indicated that the four strains are representatives of putatively novel taxa within the prolific actinobacterial genus Saccharopolyspora. The strains have typical chemotaxonomic characteristics of the genus Saccharopolyspora by having meso-diaminopimelic acid as diagnostic diaminoacid, arabinose, galactose and ribose as whole-cell sugars. Consistent with this assignment, all of the isolates contained phosphatidylcholine in their polar lipid profiles and MK-9(H4) as the predominant menaquinone. The sizes of the genomes of the isolates ranged from 6.0 to 10.2 Mb and the associated G + C contents from 69.6 to 69.7 %. Polyphasic characterizations including determination of overall genome relatedness indices revealed that the strains are representatives of four novel species in the genus Saccharopolyspora. Consequently, isolates 5K548T, 7K502T, 16K404T and 16K309T are proposed as novel Saccharopolyspora species for which the names of Saccharopolyspora karakumensis sp. nov., Saccharopolyspora elongata sp. nov., Saccharopolyspora aridisoli sp. nov. and Saccharopolyspora terrae sp. nov. are proposed, respectively. Comprehensive genome analysis for biosynthetic gene clusters showed that the strains have high potential for novel secondary metabolites. Moreover, the strains harbour many antimicrobial resistance genes providing more evidence for their potentiality for bioactive metabolites.  相似文献   

20.
A thermophilic bacterium, strain An10, was isolated from underground gas storage with methanol as a substrate and perchlorate as an electron acceptor. Cells were gram-positive straight rods, 0.4 to 0.6 μm in diameter and 2 to 8 μm in length, growing as single cells or in pairs. Spores were terminal with a bulged sporangium. The temperature range for growth was 40 to 70°C, with an optimum at 55 to 60°C. The pH optimum was around 7. The salinity range for growth was between 0 and 40 g NaCl liter−1 with an optimum at 10 g liter−1. Strain An10 was able to grow on CO, methanol, pyruvate, glucose, fructose, cellobiose, mannose, xylose, and pectin. The isolate was able to respire with (per)chlorate, nitrate, thiosulfate, neutralized Fe(III) complexes, and anthraquinone-2,6-disulfonate. The G+C content of the DNA was 57.6 mol%. On the basis of 16S rRNA analysis, strain An10 was most closely related to Moorella thermoacetica and Moorella thermoautotrophica. The bacterium reduced perchlorate and chlorate completely to chloride. Key enzymes, perchlorate reductase and chlorite dismutase, were detected in cell extracts. Strain An10 is the first thermophilic and gram-positive bacterium with the ability to use (per)chlorate as a terminal electron acceptor.  相似文献   

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