Marininema halotolerans sp. nov., a novel thermoactinomycete isolated from a sediment sample, and emended description of the genus Marininema Li et al. 2012
A novel Gram-stain-positive bacterium, designated strain YIM M11385T, was isolated from a marine sediment sample collected from the South Bay, Little Andaman Island, India with a salinity of 35 p.p.m., pH 8.5. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain YIM M11385T belongs to the genus Marininema , supported by a bootstrap value of 100 %. The taxonomic position of this organism was further established by using a polyphasic approach. Strain YIM M11385T grew optimally at 28 °C, pH 7.0 and in the presence of 0–5 % (w/v) NaCl. The 16S rRNA gene sequence similarity between strain YIM M11385T and Marininema mesophilum SCSIO 10219T was 98.3 %. Strain YIM M11385T exhibited a quinone system with only MK-7, the polar lipid profile included diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine as major components, and the major fatty acids were anteiso-C15 : 0, iso-C15 : 0, anteiso-C17 : 0 and iso-C16 : 0. The level of DNA–DNA relatedness between strain YIM M11385T and M. mesophilum SCSIO 10219T was 59.36 %. On the basis of genotypic and phenotypic data, it is apparent that strain YIM M11385T represents a novel species of the genus Marininema , for which the name Marininema halotolerans sp. nov. is proposed. The type strain is YIM M11385T ( = CCTCC AB 2012052T = DSM 45789T). In addition, we propose that the description of the genus Marininema should be further emended based on the results of the present study.