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1.
Three hundred and thirty-seven xylose-utilizing yeast strains were isolated from various natural samples. Among these, 68 strains produced xylitol in the range of 0.1–0.69 g xylitol/g xylose. Thirty-nine xylitol-producing strains were identified to be Candida tropicalis. Ten strains were found belonging to 14 known species in the genus Candida, Cyberlindnera, Meyerozyma, Pichia, Wickerhamomyces, Yamadazyma and Cryptococcus. Two strains were identified to be two Candida species and two strains (DMKU-XE142T and DMKU-XE332) were found to be a novel species. Strain DMKU-XE142T was isolated from tree bark and DMKU-XE332 was obtained from decaying plant leaf collected in Thailand. On the basis of morphological, biochemical, physiological and chemotaxonomic characteristics and sequence analysis of the D1/D2 region of the large subunit rRNA gene (LSU) and the internal transcribed spacer (ITS) region, the two strains were determined to represent a novel Yamadazyma species although formation of ascospores was not observed. The sequences of the D1/D2 region of the LSU rRNA gene and the ITS region of the two strains were identical but differed from Yamadazyma phyllophila, the closest species in terms of pairwise sequence similarity of the D1/D2 region, by 1.7 % nucleotide substitutions and 3.5 % nucleotide substitutions in the ITS region. The name Yamadazyma ubonensis f.a., sp. nov. is proposed (type strain is DMKU-XE142T = BCC 61020T = CBS 12859T).  相似文献   

2.
Three strains (KM03T, KM13 T and KM15) representing two novel methylotrophic yeast species were isolated from the external surface of plant leaves, which were collected from Kanchanaburi province, Thailand, by three-consecutive enrichments in methanol broth. Strain KM03T was isolated from phylloplane of a mango tree (Mangifera indica) and two strains, KM13T and KM15, were obtained from phylloplane of different wine grapes (Vitis vinifera). The sequences of the D1/D2 region of the large subunit (LSU) rRNA gene of the two strains (KM13T and KM15) were identical and differed markedly from that of strain KM03T. In terms of pairwise sequence similarity of the D1/D2 region the closest species to the strains KM13T and KM15 were Candida suzukii (CBS 9253T) and Candida nitratophila (CBS 2027T) but with 2.1 % nucleotide substitutions. Strain KM03T differed from Ogataea wickerhamii (CBS 4307T), its closest relative, by 2.3 % nucleotide substitutions. Phylogenetic analysis based on the D1/D2 sequences placed the three strains in the Ogataea clade. On the basis of morphological, biochemical, physiological and chemotaxonomic characteristics, the sequence analyses of the D1/D2 and the internal transcribed spacer (ITS) regions of the nuclear ribosomal RNA gene (nrRNA) operon, the three strains represent two novel Ogataea species although formation of ascospores was not observed. Ogataea kanchanaburiensis sp. nov. is proposed for strain KM03T (=BCC 47626T = NBRC 108603T = CBS 12673T). Two strains, KM13T and KM15, were assigned to Ogataea wangdongensis sp. nov. (type strain KM13T = BCC 42664T = NBRC 107778T = CBS 12674T). GenBank/EMBL/DDBJ accession numbers for the sequences of the D1/D2 and the ITS regions of O. kanchanaburiensis KM03T are AB734090 and AB734093, respectively, of O. wangdongensis KM13T are AB734091 and AB734094, respectively, and of O. wangdongensis KM15 are AB734092 and AB734095, respectively.  相似文献   

3.
Three strains representing one novel yeast species were isolated from the phylloplanes of the vetiver grasses (DMKU-LV90 and DMKU-LV99T) and sugarcane (DMKU-SP260) collected in Thailand by leaf washing followed by a plating technique. On the basis of morphological, biochemical, physiological and chemotaxonomic characteristics and the sequence analysis of the D1/D2 region of the large subunit (LSU) rRNA gene and the internal transcribed spacer region (ITS), the three strains were found to represent a single novel anamorphic ustilaginomycetous yeast species in the genus Pseudozyma. The name Pseudozyma vetiver sp. nov. is proposed for this novel species. The type strain is DMKU-LV99T (BCC 61021 = CBS 12824). The novel species showed phylogenetic relationships to the other members of the genus Pseudozyma and to teleomorphic fungal genera, namely Ustilago, Sporisorium and Anomalomyces in Ustilaginaceae, Ustilaginales. The three strains showed identical sequences both in the D1/D2 and ITS regions. The Pseudozyma species closest to the novel species in terms of pairwise sequence similarity in the D1/D2 region was Pseudozyma pruni but with 2.3 % nucleotide substitutions (14 nucleotide substitutions and no gaps out of 606 nt). The novel species and P. pruni differed by 10.9 % nucleotide substitutions (75 nucleotide substitutions and 31 gaps out of 691 nt) in the ITS region. The phylogenetic analysis based on the combined sequences of the ITS region and the D1/D2 region of the LSU rRNA gene showed that the novel species was found to be most closely related to Pseudozyma fusiformata but with 2.9 % nucleotide substitutions in the D1/D2 region and 7.4 % nucleotide substitutions in the ITS region.  相似文献   

4.
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   

5.
Three strains, YP416T, YP421T, and Y422, were isolated from soil samples in Pocheon City, Gyeonggi province, South Korea. The strains belong to two novel yeast species in the genus Mrakia. Molecular phylogenetic analysis showed that the strain YP416T was closely related to Mrakia niccombsii. Still, it differed by 9 nucleotide substitutions with no gap (1.51%) in the D1/D2 domain of the LSU rRNA gene and 14 nucleotide substitutions with 7 gaps (2.36%) in the ITS region. The strain YP421T differed from the type strain of the most closely related species, Mrakia aquatica, by 5 nucleotide substitutions with no gap (0.81%) in the D1/D2 domain of the LSU rRNA gene and 9 nucleotide substitutions with one gap (1.43%) in the ITS region. The names Mrakia terrae sp. nov. and Mrakia soli sp. nov. are proposed, with type strains YP416T (KCTC 27886T) and YP421T (KCTC 27890T), respectively. MycoBank numbers of the strains YP416T and YP421T are MB 836844 and MB 836847, respectively.  相似文献   

6.
Two strains of a novel basidiomycetous yeast species were isolated from the gut of wood-boring larvae collected in the Baotianman Nature Reserve, the central China. Sequence analysis of the D1/D2 domains of the large subunit (LSU) rRNA gene and internal transcribed spacer (ITS) regions showed that these yeasts belong to the Bulleromyces clade and formed a cluster together with eleven undescribed Cryptococcus species. The novel species differed from its closest known species, Cryptococcus rajasthanensis, by 3.3 % divergence (15 substitutions and 6 gaps over 630 bases) in the D1/D2 domains, and by 13.4 % divergence (41 substitutions and 27 gaps over 508 bases) in the ITS regions. Physiologically, the fermentation of glucose, galactose, sucrose, trehalose, and raffinose in Durham tubes was observed for the strains of this new yeast. Based on the phenotypical and molecular characteristics presented, the two strains are proposed as a new species, Cryptococcus nanyangensis sp. nov., with the type strain KCY-1T (=CICC 1976T = CBS 12474T).  相似文献   

7.
A total of 515 yeast strains were isolated from the nasal smears of Queensland koalas and their breeding environments in Japanese zoological parks between 2005 and 2012. The most frequent species in the basidiomycetous yeast biota isolated from koala nasal passages was Cryptococcus neoformans, followed by Rhodotorula minuta. R. minuta was the most frequent species in the breeding environments, while C. neoformans was rare. Seven strains representing two novel yeast species were identified. Analyses of the 26S rDNA (LSU) D1/D2 domain and nuclear ribosomal DNA internal transcribed spacer region sequences indicated that these strains represent new species with close phylogenetic relationships to Cryptococcus and Rhodotorula. A sexual state was not found for either of these two novel yeasts. Key phenotypic characters confirmed that these strains could be placed in Cryptococcus and Rhodotorula. The names Cryptococcus lacticolor sp. nov. (type strain TIMM 10013T = JCM 15449T = CBS 10915T = DSM 21093T, DDBJ/EMBL/Genbank Accession No.; AB375774 (ITS) and AB375775 (26S rDNA D1/D2 region), MycoBank ID; MB 802688, Fungal Barcoding Database ID; 3174), and Rhodotorula oligophaga sp. nov. (type strain TIMM 10017T = JCM 18398T = CBS 12623T = DSM 25814T, DDBJ/EMBL/Genbank Accession No.; AB702967 (ITS) and AB702967 (26S rDNA D1/D2 region), MycoBank ID; MB 802689, Fungal Barcoding Database ID; 3175) are proposed for these new species.  相似文献   

8.
Eleven yeast strains representing two hitherto undescribed species were isolated from different kinds of meat samples in Hungary and one from the sediment of a tropical freshwater river in Southeastern Brazil. The analysis of the sequences of their large subunit rRNA gene D1/D2 domain and the internal transcribed spacer (ITS) regions placed the two new species in the Yarrowia clade. Some of the seven strains representing the first new species can mate and give rise to asci and form ascospores embedded in capsular material, which qualifies it as the third teleomorph species of the Yarrowia clade. The name Yarrowia porcina sp. nov. (type strain: NCAIM Y.02100T = CBS 12935T = NRRL Y-63669T, allotype strain UFMG-RD131A = CBS 12932A) is proposed for this new yeast species, which, based on physiological characters, is indistinguishable from Yarrowia lipolytica and some other species of the genus. Considerable intraspecific variability was detected among the sequences of the large subunit rRNA gene D1/D2 domains of the seven strains. The variability among the D1/D2 sequences exceeded the divergence observed among the ITS sequences and in some cases more than 1 % substitution among the D1/D2 sequences was detected. The conspecificity of these strains was supported by the low (0–3 substitutions) sequence divergence among their ITS sequences, the result of a parsimony network analysis utilizing the concatenated ITS and D1/D2 sequences and also by the fingerprint patterns generated by microsatellite primed PCR. No ascospore formation was observed in the group of the other five strains representing the second new species. These strains shared identical D1/D2 and ITS sequences. Yarrowia bubula f.a., sp. nov. (type strain: NCAIM Y.01998T = CBS 12934T = NRRL Y-63668T) is proposed to accommodate these strains.  相似文献   

9.
The increase of infections due to non-Candida albicans species made it very necessary to conduct adequate characterization to be able to identify the species of Candida isolated from traditional fermented foods. In this study, based on their hue on Candida Chromogenic Agar medium, a total of 136 yeast strains were isolated from tchapalo and bangui. Molecular identification based on PCR-RFLP of internal transcribed spacers of rDNA (ITS) and sequencing of the ITS and the D1/D2 regions allowed us to assign these isolates to seven species: Candida tropicalis, Candida inconspicua, Candida rugosa, Saccharomyces cerevisiae, Kluyveromyces marxianus, Hanseniaspora guilliermondii, Trichosporon asahii. With the respect to each beverage, six species were found among with four species are regarded as opportunistic pathogens. From these, C. tropicalis, C. inconspicua and K. marxianus were the most commonly encountered. The enzyme activities of the potential pathogens assessed using API ZYM system showed that almost strains had esterase, esterase lipase, valine and cystine arylamidase, alpha chymotrypsin, alkaline phosphatase and naphthol phosphohydrolase activities. The activity of α-glucosidase was found only in C. tropicalis and C. inconspicua strains isolated from tchapalo while β-glucosidase activity was found in all strains from tchapalo and only in C. inconspicua isolated from bangui.  相似文献   

10.
Yeasts were isolated by the enrichment technique from the phylloplane of 94 samples of sugarcane leaf collected from seven provinces in Thailand. All sugarcane leaf samples contained yeasts and 158 yeast strains were obtained. On the basis of the D1/D2 domain of the large subunit rRNA gene sequence analysis, 144 strains were identified to 24 known species in 14 genera belonging to the Ascomycota viz. Candida akabanensis, Candida dendronema, Candida mesorugosa, Candida michaelii, Candida nivariensis, Candida rugosa, Candida orthopsilosis, Candida quercitrusa, Candida tropicalis, Candida xylopsoci, Cyberlindnera fabianii, Cyberlindnera rhodanensis, Debaryomyces nepalensis, Hannaella aff. coprosmaensis, Hanseniaspora guilliermondii, Kluyveromyces marxianus, Lachancea thermotolerans, Lodderomyces elongisporus, Metschnikowia koreensis, Meyerozyma caribbica, Millerozyma koratensis, Pichia kudriavzeviiTorulaspora delbrueckii and Wickerhamomyces edaphicus, and 12 species in six genera of the Basidiomycota viz . Cryptococcus flavescens, Cryptococcus laurentii, Cryptococcus rajasthanensis, Kwoniella heveanensis, Rhodosporidium fluviale, Rhodosporidium paludigenum, Rhodotorula mucilaginosa, Rhodotorula sesimbrana, Rhodotorula taiwanensis, Sporidiobolus ruineniae, Sporobolomyces carnicolor and Sporobolomyces nylandii. Seven strains were identical or similar to four undescribed species. Another seven strains represented four novels species in the genus Metschnikowia, Nakazawaea, Wickerhamomyces and Yamadazyma. The results revealed 69 % of the isolated strains were ascomycete yeasts and 31 % were basidiomycete yeast. The most prevalent species was M. caribbica with a 23 % frequency of occurrence followed by Rh. taiwanensis (11 %) and C. tropicalis (10 %). All strains were assessed for indole-3-acetic acid (IAA) producing capability showing that 69 strains had the capability of producing IAA when cultivated in yeast extract peptone dextrose broth supplemented with 1 g/L l-tryptophan. The highest IAA concentration of 565.1 mg/L was produced by R. fluviale DMKU-RK253.  相似文献   

11.
Ascomycetous yeast strain SM-22 was isolated from the sea-surface microlayer near the Keelung City off the northern coast of Taiwan. This strain showed a cell surface hydrophobicity higher than 90 %, moderate UV A/B resistance, and it degraded 68 % of the total petroleum hydrocarbon content of an artificial seawater medium containing 1 % (v v?1) diesel oil within 15 days at 25 °C. The closest phylogenetic relative of this strain is Candida oslonensis CBS 10146T, but it differs from strain SM-22 by a 3.7 % divergence (including 18 nucleotide substitutions and 2 gaps) in the D1/D2 domain sequence of the large subunit rRNA gene. This difference clearly suggests that the strain SM-22 represents a distinct species. Strain SM-22 does not produce ascospores on common sporulation media and it can therefore be considered an anamorph of the genus Yarrowia. Thus, the name Yarrowia keelungensis sp. nov. (type strain SM-22T = BCRC 23110T = JCM 14894T = CBS 11062T) is proposed as a novel species of genus Yarrowia.  相似文献   

12.
13.
A new yeast species (KKU-FW10) belonging to the Candida genus was isolated from Jasminum adenophyllum in the Plant Genetic Conservation Project under The Royal Initiative of Her Royal Highness Princess Maha Chakri Sirindhorn area, Chulabhorn Dam, Konsan district within Chaiyaphum province in Thailand. The strain was identified via analysis of nucleotide sequences from the D1/D2 domain of 26S ribosomal DNA and based on its morphological, physiological and biochemical characteristics. The sequence obtained from yeast isolate KKU-FW10 was 97 percent identical to that of Candida chanthaburiensis (GenBank accession number AB500861.1), with 506/517 (nucleotides identity/total nucleotides) matching nucleotides, nine substitutions and two gaps being detected. This species belonged to the Candida clade. Regarding morphological characteristics, isolate KKU-FW10 presents cream-colored butyrous colonies, vegetative reproduction through budding and, round cells without filaments or ascospores. The major ubiquinone detected was Q-9. The above results suggest that isolate KKU-FW10 is a new member of the genus Candida, and the name Candida konsanensis is proposed for this yeast. The type strain of the new species is KKU-FW10T (= BCC 52588T, = NBRC 109082T, = CBS 12666T). In addition, this KKU-FW10 could potentially produce 58.24 Units/ml of carboxymethyl cellulase when it was cultured in YP broth containing 1.0 % carboxymethyl cellulose for 24 h.  相似文献   

14.
A novel actinomycete strain, designated TRM 49605T, was isolated from a desert soil sample from Lop Nur, Xinjiang, north-west China, and characterised using a polyphasic taxonomic approach. The strain exhibited antifungal activity against the following strains: Saccharomyces cerevisiae, Curvularia lunata, Aspergillus flavus, Aspergillus niger, Fusarium oxysporum, Penicillium citrinum, Candida albicans and Candida tropicalis; Antibacterial activity against Bacillus subtilis, Staphylococcus epidermidis and Micrococcus luteus; and no antibacterial activity against Escherichia coli. Phylogenetic analysis based on 16S rRNA gene sequences affiliated strain TRM 49605T to the genus Streptomyces. Strain TRM 49605T shows high sequence similarities to Streptomyces roseolilacinus NBRC 12815T (98.62 %), Streptomyces flavovariabilis NRRL B-16367T (98.45 %) and Streptomyces variegatus NRRL B-16380T (98.45 %). Whole cell hydrolysates of strain TRM 49605T were found to contain ll-diaminopimelic acid as the diagnostic diamino acid and galactose, glucose, xylose and mannose as the major whole cell sugars. The major fatty acids in strain TRM 49605T were identified as iso C16:0, anteiso C15:0, C16:0 and Summed Feature 5 as defined by MIDI. The main menaquinones were identified as MK-9(H4), MK-9(H6), MK-9(H8) and MK-10(H6). The polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, phosphatidylinositol and phosphatidylinositol mannoside. The G+C content of the genomic DNA was determined to be 71.2 %. The DNA–DNA relatedness between strain TRM 49605T and the phylogenetically related strain S. roseolilacinus NBRC 12815T was 60.12 ± 0.06 %, which is lower than the 70 % threshold value for delineation of genomic prokaryotic species. Based on the phenotypic, chemotaxonomic and phylogenetic data, strain TRM 49605T (=CCTCC AA2015026T = KCTC 39666T) should be designated as the type strain of a novel species of the genus Streptomyces, for which the name Streptomyces luozhongensis sp. nov. is proposed.  相似文献   

15.
Two novel ascomycetous yeast species, Saturnispora serradocipensis and Saturnispora gosingensis, were isolated from leaf detritus in a tropical stream of Southeastern Brazil and a mushroom collected in Taiwan, respectively. Analysis of the D1/D2 domains of the large-subunit of the rRNA gene of these strains showed that these species are related to Saturnispora hagleri, their closest relative. Saturnispora serradocipensis and S. gosingensis differed from S. hagleri, respectively, by seven nucleotide substitutions and two indels and three nucleotide substitutions and three indels in D1/D2 rRNA sequences. The two new species differ from each another by four nucleotide substitutions and one indel in D1/D2 rRNA sequences. However, the ITS sequences of S. serradocipensis, S. gosingensis and S. hagleri were quite divergent, showing that they are genetically separate species. The type strain of S. serradocipensis is UFMG-DC-198T (=CBS 11756T = NRRL Y-48717T), and of S. gosingensis GA4M05T is (CBS 11755T = NRRL Y-48718T).  相似文献   

16.
Four yeast strains were isolated from rotting wood samples collected from two sites in the Baotianman Nature Reserve and the Laojieling Nature Reserve in China. DNA sequence comparison and other taxonomic characteristics identified the strains as a single novel species of the genus Metschnikowia. The name Metschnikowia henanensis sp. nov. is proposed to accommodate these highly divergent organisms with the type strain BY-97T (= CICC 1982T = CBS 12677T). The novel species produced chlamydospores, but it did not exhibit ascospore formation in sporulation media for 4 weeks. Molecular phylogeny from the D1/D2 domains of the large subunit (LSU) rRNA gene sequences placed this new species in a basal position to the Metschnikowia viticola/Candida kofuensis/Metschnikowia noctiluminum subclade, and an undescribed Candida species namely strains IMB-EMP4 and IMB-EMP5 was a close sister to M. henanensis.  相似文献   

17.
Brown rot caused by Monilinia spp. is among the most important postharvest diseases of commercially grown stone fruits, and application of antagonistic yeasts to control brown rot is one promising strategy alternative to chemical fungicides. In this research, new yeast strains were isolated and tested for their activity against peach brown rot caused by Monilinia fructicola. Three yeast strains were originally isolated from the surface of plums (cv Chinese Angelino) collected in the north of China. In artificially wounded inoculation tests, the yeast reduced the brown rot incidence to 20 %. The population of the yeast within inoculated wounds on peaches significantly increased at 25 °C from an initial level of 5.0 × 106 to 4.45 × 107 CFU per wound after 1 day. The antagonistic strains were belonging to a new species of the genus Candida by sequence comparisons of 26 S rDNA D1/D2 domain and internal transcribed spacer region. The strains are most closely related to C. asparagi, C. musae and C. fructus on the basis of the phylogenetic trees based on the D1/D2 region of 26S rDNA. However, the strains are notably different from C. asparagi, C. musae and C. fructus, in morphological and physiological characteristics. Therefore, the name Candida pruni is proposed for the novel species, with sp-Quan (=CBS12814T = KCTC 27526T = GCMC 6582T) as the type strain. Our study showed that Candida pruni is a novel yeast species with potential biocontrol against brown rot caused by M. fructicola on peaches.  相似文献   

18.
A Gram-negative, aerobic, non-motile and ovoid or rod-shaped bacterial strain, GGW-M5T, was isolated from seawater on the southern coast in Korea, and its taxonomic position was investigated by using a polyphasic approach. Strain GGW-M5T grew optimally at pH 7.0–8.0, at 30 °C and in the presence of 2 % (w/v) NaCl. A neighbour-joining phylogenetic tree based on 16S rRNA gene sequences revealed that strain GGW-M5T belonged to the genus Glaciecola, joining the cluster comprising the type strains of G. agarilytica, G. arctica, G. chathamensis, G. mesophila, G. polaris and G. psychrophila, with which it exhibited 16S rRNA gene sequence similarity values of 95.9–96.7 %. Strain GGW-M5T exhibited sequence similarity values of 93.2–94.8 % to the type strains of the other Glaciecola species. Strain GGW-M5T contained Q-8 as the predominant ubiquinone and C16:1 ω7c and/or iso-C15:0 2-OH, C16:0 and C14:0 2-OH as the major fatty acids. Major polar lipids were phosphatidylglycerol, phosphatidylethanolamine and diphosphatidylglycerol. The DNA G+C content was 42.4 mol%. Differential phenotypic properties, together with the phylogenetic distinctiveness, demonstrated that strain GGW-M5T could be distinguished from other Glaciecola species. On the basis of the data presented, strain GGW-M5T is considered to represent a novel species of the genus Glaciecola, for which the name Glaciecola aquimarina sp. nov. is proposed. The type strain is GGW-M5T (=KCTC 32108T = CCUG 62918T).  相似文献   

19.
Two deltaproteobacterial sulfate reducers, designated strain I.8.1T and I.9.1T, were isolated from the oxygen minimum zone water column off the coast of Peru at 400 and 500 m water depth. The strains were Gram-negative, vibrio-shaped and motile. Both strains were psychrotolerant, grew optimally at 20°C at pH 7.0–8.0 and at 2.5–3.5% NaCl (w/v). The strains grew by utilizing hydrogen/acetate, C3–4 fatty acids, amino acids and glycerol as electron acceptors for sulfate reduction. Fumarate, lactate and pyruvate supported fermentative growth. Sulfate, sulfite, thiosulfate and taurin supported growth as electron acceptors. Both strains were catalase-positive and highly oxygen-tolerant, surviving 24 days of exposure to atmospheric concentrations. MK6 was the only respiratory quinone. The most prominent cellular fatty acid was iso-17:1-ω9c (18%) for strain I.8.1T and iso-17:0-ω9c (14%) for strain I.9.1T. The G+C contents of their genomic DNA were 45–46 mol%. Phylogenetic analysis of 16S rRNA and dsrAB gene sequences showed that both strains belong to the genus Desulfovibrio. Desulfovibrio acrylicus DSM 10141T and Desulfovibrio marinisediminis JCM 14577T represented their closest validly described relatives with pairwise 16S rRNA gene sequence identities of 98–99%. The level of DNA-DNA hybridization between strains I.8.1T and I.9.1T was 30–38%. The two strains shared 10–26% DNA-DNA relatedness with D. acrylicus. Based on a polyphasic investigation it is proposed that strains I.8.1T and I.9.1T represent a novel species for which the name Desulfovibrio oceani sp. nov. is proposed with the two subspecies D. oceani subsp. oceani (type strain, I.8.1T = DSM 21390T = JCM 15970T) and D. oceani subsp. galateae (type strain, I.9.1T = DSM 21391T = JCM 15971T).  相似文献   

20.
A Gram-negative, aerobic, non-motile and rod-shaped or ovoid bacterial strain, designated D1-W8T, was isolated from a tidal flat on the South Sea in South Korea. Strain D1-W8T was found to grow optimally at 25 °C, at pH 7.0–8.0 and in the presence of 2.0–3.0 % (w/v) NaCl. Neighbour-joining, maximum-likelihood and maximum-parsimony phylogenetic trees based on 16S rRNA gene sequences revealed that strain D1-W8T clustered with the type strain of Pelagicola litoralis showing 97.1 % sequence identity. 16S rRNA gene sequences of the type strains of other species exhibited lower similarity values. Strain D1-W8T was determined to contain Q-10 as the predominant ubiquinone and C18:1 ω7c as the predominant fatty acid. The major polar lipids of strain D1-W8T were identified as phosphatidylcholine, phosphatidylglycerol, phosphatidylethanolamine, one unidentified aminolipid and one unidentified lipid. The DNA G+C content of strain D1-W8T was determined to be 57.9 mol% and its DNA–DNA relatedness value with the type strain of P. litoralis was 17 %. The differential phenotypic properties, together with the phylogenetic and genetic distinctiveness, revealed that strain D1-W8T is separate from P. litoralis. On the basis of the data presented, strain D1-W8T is considered to represent a novel species of the genus Pelagicola, for which the name Pelagicola litorisediminis sp. nov. is proposed. The type strain is D1-W8T (= KCTC 32327T = CECT 8287T).  相似文献   

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