Y. Subhash
Kyonggi University
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International Journal of Systematic and Evolutionary Microbiology | 2016
Y. Subhash; John J. Bang; Taek H. You; Sang-Seob Lee
A novel Gram-stain-negative, coccus to oval-shaped, non-motile bacterium, designated strain S5T, was isolated from lagoon sediments collected from North Carolina, USA. Strain S5T was able to grow at 12-45 °C (optima, 30-37 °C) and at pH 6.3-9.0 (optima, 6.5-7.5). No added NaCl was required for growth of strain S5T. Strain S5T was positive for catalase and oxidase activity. C18 : 1ω6c/C18 : 1ω7c, C16 : 1ω6c/C16 : 1ω7c and C16 : 0 were predominant fatty acids with minor amounts of C8 : 0 3-OH, C14 : 0, C16 : 0 3-OH, C18 : 1 2-OH, C14 : 1ω5c, C16 : 1ω5c and C19 : 0 cyclo ω8c. Diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine and an unidentified glycolipid were major polar lipids. Minor amounts of an unidentified amino lipid and three unidentified lipids were also detected. The G+C content of the genomic DNA was 73.5 mol%. 16S rRNA gene sequence comparisons indicated that strain S5T represents a member of the genus Roseomonas within the family Acetobacteraceae of the class Alphaproteobacteria. Strain S5T had a sequence similarity of 97.80 % with Roseomonas rhizosphaerae YW11T, 97.69 % with Roseomonas aestuarii JC17T and <97 % with other members of the genus Roseomonas. However, strain S5T showed only 45.2±2 and 17±2 % relatedness (based on DNA-DNA hybridization) with R. rhizosphaerae KACC 17225T (=YW11T) and R. aestuarii KCTC 22692T (=JC17T), respectively. Distinct morphological, physiological and genotypic differences from previously described taxa support the classification of strain S5T as a representative of a novel species in the genus Roseomonas, for which the name Roseomonas rubra sp. nov. is proposed. The type strain is S5T (=KEMB 563-468T=JCM 31177T).
International Journal of Systematic and Evolutionary Microbiology | 2016
Y. Subhash; John J. Bang; Taek H. You; Sang-Seob Lee
Strain S3T was isolated from lagoon sediments, and appeared as transparent colonies on agar plates, with cells staining Gram-negative. Catalase and oxidase were positive. S3T hydrolyzed starch, casein and tween-20, while urea, chitin, gelatin and tween-80 were not hydrolysed. C18 : 1ω6c/C18 : 1ω7c, C16 : 1ω6c/C16 : 1ω7c,C17 : 0 cyclo and C16 : 0 were the predominant fatty acids with minor amounts of C10 : 0 3-OH, C12 : 0, C14 : 0 and C16 : 0 2-OH. S3T contained diphosphatidylglycerol (DPG), phosphatidylglycerol (PG), and phosphatidylethanolamine (PE) as major polar lipids with minor amounts of unidentified phospholipid (PL) and unidentified lipids (L1-2). Genomic DNA G+C content was 68.3 mol%. 16S rRNA gene sequence comparisons indicated that S3T represents a member of the genus Comamonas in family Comamonadaceae of the class Betaproteobacteria. S3T has a sequence similarity of 98.96 % with Comamonas koreensis YH12T, 97.93 % with Comamonas guangdongensis CY01T and <96.97 % with other members of the genus Comamonas. DNA-DNA hybridization values between S3T and the type strains of the most closely related species were clearly below the 70 % threshold. On the basis of phenotypic, genotypic and phylogenetic analysis, it is proposed that S3T represents a novel species of the genus Comamonas, for which the name Comamonas sediminis sp. nov. is proposed. The type strain is S3T (=KEMB 563-466T =JCM 31169T).
International Journal of Systematic and Evolutionary Microbiology | 2016
Y. Subhash; Sang-Seob Lee
The taxonomic position of a novel bacterial strain, designated C3T, isolated from hydrocarbon-contaminated desert sands was determined. Strain C3T was a Gram-stain-negative, rod- to curved-rod-shaped and non-motile bacterium. It was able to grow at 4-45 °C (optima, 28- 35 °C) and at pH 6.1-8.8 (optima, 6.9-7.7). No added NaCl was required for growth of strain C3T and it tolerated up to 3.5 % (w/v) NaCl with optimal growth with 0.5-1.5 %. Catalase and oxidase were positive. C18 : 1ω6c/C18 : 1ω7c, C16 : 0, C12 : 0 aldehyde, C14 : 0 3-OH/iso-C16 : 0 I and C18 : 1ω7c 11-methyl were predominant fatty acids. Diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and phosphatidylcholine were major polar lipids. The genomic DNA G+C content was 65.4 mol%. 16S rRNA gene sequence comparisons indicated that strain C3T represents a member of the genus Shinella within the family Rhizobiaceae of the class Alphaproteobacteria. Strain C3Tshowed a 16S rRNA gene sequence similarity of 98.39 % with Shinella kummerowiae CCBAU 25048T, 98.37 % with Shinella granuli Ch06T, 98.17 % with Shinella zoogloeoides I-16-MT, 97.74 % with Shinella fusca DC-196T, 97.46 % with Shinella yambaruensis MS4T and <96.68 % with other members of the family Rhizobiaceae. DNA-DNA hybridization values between strain C3T and the type strains of the nearest species were clearly below the 70 % threshold for species delineation. Distinct morphological, physiological and genotypic differences from previously described taxa support the classification of strain C3T as a representative of a novel species in the genus Shinella, for which the name Shinella curvata sp. nov. is proposed. The type strain is C3T (=KEMB 2255-446T=JCM 31239T).
International Journal of Systematic and Evolutionary Microbiology | 2016
Y. Subhash; Sang-Seob Lee
A novel Gram-stain-negative, small rod-shaped, motile strain, designated M1T, was isolated from hydrocarbon-contaminated desert sands collected from Kuwait. M1T grew at 12-45 °C, pH 6.1-8.8 and 0-4.5 % (w/v) NaCl concentration. Casein, Tween-20 and Tween-80 were hydrolyzed while starch, urea, chitin, DNA and carboxymethyl-cellulose were not hydrolyzed by M1T. C18 : 1ω6c/C18 : 1ω7c, C16 : 0 and C12 : 0 aldehyde were predominant fatty acids with minor amounts of iso-C16 : 1I/C14 : 0 3-OH, C16 : 0 3-OH, C18 : 0, C16 : 1ω6c/C16 : 1ω7c, C16 : 1ω11c and C18 : 1ω9c. Diphosphatidylglycerol (DPG), phosphatidylglycerol (PG), phosphatidylethanolamine (PE) and phosphatidylcholine (PC) were the major polar lipids. Minor amounts of unidentified aminolipids (AL1-2), unidentified phospholipids (PL1-2) and unidentified lipids (L1-4) were also detected. Genomic G+C content was 69.5 mol%. Comparisons of 16S rRNA gene sequence indicate that M1T represent a member of the genus Skermanella in the family Rhodospirillaceae of the class Alphaproteobacteria. M1T has a sequence similarity of 97.5 % with Skermanella aerolata 5416T-32T, 96.7 % with Skermanella stibiiresistens SB22T and <95.7 % with the other two species of the genus Skermanella. DNA-DNA hybridization values between M1T and the type strains of the most closely related species were clearly below the 70 % threshold. Distinct morphological, physiological and genotypic differences from the previously described taxa support the classification of strain M1T as a representative of a novel species in the genus Skermanella, for which the name Skermanella rosea sp. nov. is proposed. The type strain is M1T (=KEMB 2255-458T=JCM 31276T).
International Journal of Systematic and Evolutionary Microbiology | 2016
Y. Subhash; Sang-Seob Lee
Two Gram-stain-negative, rod-shaped phototrophic bacteria (designated strains N1T and C7) were isolated from lagoon sediments. Both strains were positive for catalase and oxidase activity. Casein, starch, urea and Tween 20 were hydrolysed by both strains while chitin, gelatin and Tween 80 were not. In both strains, C16 : 0, C18 : 0,C16 : 1ω6c/C16 : 1ω7c and C18 : 1ω6c/ C18 : 1ω7c were the predominant fatty acids, with minor amounts of C8 : 0 3-OH, anteiso-C14 : 0, C17 : 0, C14 : 1ω5c, C17 : 1 10-methyl and C18 : 1ω5c. Strains N1T and C7 contained phosphatidylglycerol and phosphatidylethanolamine as major polar lipids with minor amounts of phosphatidylcholine, unidentified lipids and an unidentified phospholipid. The mean genomic DNA G+C content was 70.6±1 mol% and the two strains were closely related (mean DNA-DNA hybridization >90 %). Phylogenetic analysis based on 16S rRNA gene sequences showed that the two strains clustered with species of the genus Rhodobacter belonging to the family Rhodobacteraceae of the class Alphaproteobacteria. Strain N1T has a 16S rRNA gene sequence similarity of 99.2 % with Rhodobacter capsulatus ATCC 11166T, 99.1 % with Rhodobacter viridis JA737T and <96.6 % with other members of the genus Rhodobacter. Strain N1T and C7 shared 100 % 16S rRNA gene sequence similarity. DNA- DNA hybridization values between strain N1T and the type strains of the nearest species were clearly below the 70 % threshold. On the basis of phenotypic and genotypic data, it is proposed that strain N1T represents a novel species of the genus Rhodobacter, for which the name Rhodobacter sediminis sp. nov. is proposed. The type strain is N1T (=KEMB 563-471T=JCM 31175T), and strain C7 is an additional strain of the species.
International Journal of Systematic and Evolutionary Microbiology | 2016
Y. Subhash; Min-Jeong Park; Sang-Seob Lee
A novel Gram-stain-negative, small curved-rod-shaped, motile strain, designated L6T, was isolated from hydrocarbon-contaminated soils collected from Kuwait. Strain L6T was able to grow at 10-40 °C (optimum, 27-32 °C), pH 6.1-8.8 (optimum, 6.5-7.5) and 0-4.5 % (w/v) NaCl (optimum, 0-0.5). C18 : 1ω6c/C18 : 1ω7c, C16 : 0, C16 : 1ω6c/C16 : 1ω7c, C12 : 0 and C12 : 0 3-OH were predominant fatty acids with minor amounts of C14 : 0 and C17 : 0 cyclo. Phosphatidylglycerol and phosphatidylethanolamine were major polar lipids. The genomic G+C content was 61.2 mol%. 16S rRNA gene sequence comparisons indicated that strain L6T represents a member of the genus Microvirgula within the family Neisseriaceae of the class Betaproteobacteria. Strain L6T has a sequence similarity of 99.2 % with Microvirgula aerodenitrificans SGLY2T and <93.8 % with other members of the family Neisseriaceae. However, strain L6T showed only 56.5±2 % relatedness (based on DNA-DNA hybridization) with M. aerodenitrificans KACC 12055T (=SGLY2T). Distinct morphological, physiological and genotypic differences from the previously described taxa support the classification of strain L6T as a representative of a novel species in the genus Microvirgula, for which the name Microvirgula curvata sp. nov. is proposed. The type strain is L6T (=KEMB 2255-471T=JCM 31223T). An emended description of the genus Microvirgula is also proposed.
International Journal of Systematic and Evolutionary Microbiology | 2017
Y. Subhash; Sang-Seob Lee
Three light-brown-coloured, Gram-stain-negative, small rod- to oval-shaped, motile bacteria were isolated from lagoon sediments collected from North Carolina, USA. The strains (S1T, AS3 and AS6) grew aerobically at 13-42 °C (optimum, 30-35 °C) and pH 6.5-9.1 (optimum, pH 7.0-7.5). All three strains were positive for catalase and oxidase activity, and no added NaCl was required for growth. C18 : 1ω6c/C18 : 1ω7c, C16 : 1ω6c/C16 : 1ω7c, C18 : 1ω7c 11-methyl and C16 : 0 were the predominant fatty acids (>5 %). Diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine and an unidentified glycolipid were the major polar lipids. The genomic DNA G+C content of strains S1T, AS3 and AS6 was 70.5, 70.1 and 70.8 mol%, respectively. Strain S1T showed 16S rRNA gene sequence similarity of 99.1 % with Roseomonas rubra S5T, 98.7 % with Roseomonas rhizosphaerae YW11T, 98.5 % with Roseomonas cervicalis E7107T, 97.8 % with Roseomonas aestuarii JC17T, 97.2 % with Roseomonas oryzae JC288T, 97.2 % with Roseomonas ludipueritiae 170/96Tand <97 % with other members of the genus Roseomonas. Strains AS3 and AS6 shared 99.9 % 16S rRNA gene sequence similarity with strain S1T. DNA-DNA hybridization values among strains S1T, AS3 and AS6 were >89 %, while all the three strains showed <56 % relatedness with the most closely related type strains. Distinct phenotypic, genotypic and phylogenetic differences from the previously described taxa support the classification of strain S1T as a representative of a novel species in the genus Roseomonas, for which the name Roseomonas suffusca sp. nov. is proposed. The type strain is S1T (=KEMB 563-465T=JCM 31176T). Strains AS3 and AS6 serve as additional strains of the newly proposed species.
International Journal of Systematic and Evolutionary Microbiology | 2018
Y. Subhash; Sang-Seob Lee
Two dark pink pigmented bacterial strains (M3T and M11) were isolated from crude oil contaminated desert sand from Kuwait. Both strains were Gram-stain-negative and small-rod to oval-shaped bacteria. Strains M3T and M11 grew at 13-42 °C (optimum, 30-35 °C) and pH 6.5-9.0 (optimum, 7.0-7.5). No additional NaCl was required for the growth of both strains. The genomic DNA G+C content of strains M3T and M11 were 69.5 and 69.0 mol%, respectively. Both strains were closely related and the mean DNA-DNA hybridization value was 92±1 %. 16S rRNA gene sequence comparisons of both strains indicated that they belong to the genus Roseomonas. Strains M3T and M11 had a sequence similarity of 97.3 and 97.4 % with Roseomonas oryzae JC288T, respectively. Both strains had <97 % 16S rRNA gene sequence similarity with other members of the genus Roseomonas. Strain M3T showed 18±2 and 13±2 % reassociation (based on DNA-DNA hybridization) with R. oryzae KCTC 42542T and Roseomonas cervicalis KACC 11686T, respectively. The major cellular fatty acids (>5 %) were identified as C18 : 1ω6c/C18 : 1ω7c, C16 : 1ω6c/C16 : 1ω7c and C16 : 0 in both strains. Both strains showed diphosphatidylglycerol, phosphatidylglycerol, phosphatidyl-ethanolamine, phosphatidylcholine and unidentified glycolipid as major polar lipids. Based on distinct phenotypic, genotypic and phylogenetic differences from the previously described taxa, we propose the classification of strains M3T and M11 as representative of a novel species in the genus Roseomonas, for which the name Roseomonas deserti sp. nov. is suggested. The type strain is M3T (=KEMB 2255-459T=JCM 31275T).
International Journal of Systematic and Evolutionary Microbiology | 2017
Da-Hye Jin; Y. Subhash; Sang-Seob Lee
Strain 10R5-21T was isolated from lagoon sediments. Cells of strain 10R5-21T were Gram-reaction-negative, rod-shaped and motile by means of polar flagella. The strain was obligately aerobic and positive for catalase and oxidase activity. Strain 10R5-21T was able to grow at 10-37 ˚C (optimum 25-30 ˚C), at pH 5.0-9.0 (optimum pH 6.5-7.5) and in the presence of 0-0.5 % (w/v) NaCl (optimum 0 %). C16 : 1ω7c/C16 : 1ω6c, C16 : 0 and C12 : 0 were present as predominant (>5 %) fatty acids. Q-8 was identified as the major respiratory quinone. Diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine were present as major polar lipids with minor amounts of unidentified aminophospholipids and unidentified aminolipids. The genomic G+C content of strain 10R5-21T was 64.1 mol%. 16S rRNA gene sequence analysis indicated that strain 10R5-21T belongs to the genus Pseudoduganella within the family Oxalobacteraceae of the class Betaproteobacteria. Strain 10R5-21T shared 98.8 % 16S rRNA gene sequence similarity with Pseudoduganella violaceinigra YIM 31327T. DNA-DNA hybridization values between strain 10R5-21T and P. violaceinigra KACC 11669T were clearly below the 70 % threshold. Distinct morphological, biochemical, chemotaxonomic and genetic differences from previously described taxa support the classification of strain 10R5-21T as a representative of a novel species in the genus Pseudoduganella, for which the name Pseudoduganella eburnea sp. nov. is proposed. The type strain is 10R5-21T (=KEMB 563-061T=JCM 31587T).
International Journal of Systematic and Evolutionary Microbiology | 2017
Y. Subhash; Sang-Seob Lee
An obligately anaerobic spirochaete (strain SY2T) was isolated from coastal marine sediments of Tongyeong-Si, South Korea. Strain SY2T was helical-shaped and Gram-stain-negative. Strain SY2T was able to grow at 10-40 °C (optima, 25-30 °C), pH 6.3-8.8 (optima, pH 7.0-8.0) and with 1-7 % (optimum, 2-3 %) NaCl concentration. Strain SY2T was negative for catalase and oxidase activity. The major end-products of glucose fermentation were acetate, ethanol, hydrogen and carbon dioxide. C14 : 0, C16 : 0, iso-C15 : 0, iso-C14 : 0 3-OH, iso-C15 : 1 H/C13 : 0 3-OH and iso-C17 : 1ω9c were predominant fatty acids (>5 %) with minor amounts (<5 %) of C18 : 0, iso-C13 : 0, iso-C17 : 0, iso-C17 : 1/anteiso-C17 : 1 B and C16 : 1ω6c/C16 : 1ω7c. Diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine were major polar lipids. The genomic DNA G+C content was 53.5 mol%. 16S rRNA gene sequence comparisons indicated that strain SY2T represents a member of the family Spirochaetaceae in the phylum Spirochaetes. Strain SY2T has a sequence similarity of 95.1 % with Spirochaeta litoralis R1T and <90.1 % with other members of the genus Spirochaeta. Distinct morphological, physiological and genotypic differences from the previously described taxa support the classification of strain SY2T as a representative of a novel genus and species in the family Spirochaetaceae, for which the name Oceanispirochaeta sediminicola gen. nov., sp. nov. is proposed. The type strain is SY2T (=KEMB 3001-381T=DSM 104770T=KCTC 15593T). Reclassification of Spirochaeta litoralis as Oceanispirochaeta litoralis comb. nov. is also proposed based on polyphasic taxonomic analyses.