RESUMO
Three Gram-stain-positive, catalase- and oxidase-positive coccus- or rod-shaped bacterial strains, designated BM2T, BM4 and BM5, were isolated from soil in South Korea. They showed strong resistance to gamma radiation with a D10 value of 9âkGy but weak UVC resistance. The 16S rRNA sequences of strains BM2T, BM4 and BM5 represent a novel subline within the genus Deinococcus in the family Deinococcaceae. The 16S rRNA gene sequences of strains BM2T, BM4 and BM5 were indistinguishable and showed 98.1-87.3 % similarity with other species of the genus Deinococcus. Strain BM2T exhibited relatively high levels of DNA-DNA hybridization with BM4 (87 ± 0.8 %) and BM5 (92 ± 1.2 %). Meanwhile, it showed a low level of DNA-DNA hybridization ( < 30 %) with other closely related species of the genus Deinococcus. The strains showed the typical chemotaxonomic characteristics of the genus Deinococcus, with the presence of menaquinone 8 as the respiratory quinone; the major fatty acids were summed feature 3 (composed of C16 : 1ω7c/C16 : 1ω6c), C15 : 1ω6c and C16 : 0. The DNA G+C content of strain BM2T was 69.7âmol%. The polar lipid profile included major amounts of phosphatidylglycerol, phosphatidylcholine and an unknown aminolipid. On the basis of phenotypic and genotypic properties, and phylogenetic distinctiveness, strains BM2T, BM4 and BM5 should be classified in a novel species in the genus Deinococcus, for which the name Deinococcus actinosclerus sp. nov. is proposed. The type strain is BM2T ( = KEMB 5401-184T = JCM 30700T); reference strains are BM4 ( = JCM 30701) and BM5 ( = JCM 30702).
RESUMO
A Gram-stain-negative, aerobic, non-spore-forming, non-flagellated and coccoid, ovoid or rod-shaped bacterial strain, designated AH-M8T, was isolated from a tidal flat sediment collected from Aphae Island in the south-western sea, South Korea. Strain AH-M8T grew optimally at 35 °C, at pH 7.0-8.0 and in the presence of 2.0-3.0% (w/v) NaCl. A neighbour-joining phylogenetic tree based on 16S rRNA gene sequences revealed that strain AH-M8T belonged to the genus Sphingomicrobium, clustering with the type strain of Sphingomicrobium astaxanthinifaciens, with which it shared 99.0% 16S rRNA gene sequence similarity. Sequence similarities to the type strains of other species of the genus Sphingomicrobium were 95.4-96.0%. Strain AH-M8T contained Q-10 as the predominant ubiquinone and C18 : 1ω7c, summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c) and C16 : 0 as the major fatty acids. The major polar lipids of strain AH-M8T were phosphatidylglycerol, phosphatidylethanolamine, sphingoglycolipid and one unidentified glycolipid. The major polyamine is triamine sym-homospermidine. The DNA G+C content of strain AH-M8T was 66.7âmol% and its mean DNA-DNA relatedness value with S. astaxanthinifaciens JCM 18551T was 21%. The differential phenotypic properties, together with the phylogenetic and genetic distinctiveness, revealed that strain AH-M8T is separated from other species of the genus Sphingomicrobium. On the basis of the data presented, strain AH-M8T is considered to represent a novel species of the genus Sphingomicrobium, for which the name Sphingomicrobium aestuariivivum sp. nov. is proposed. The type strain is AH-M8T ( = KCTC 42286T = NBRC 110678T).
