Thioclava atlantica sp. nov., isolated from deep sea sediment of the Atlantic Ocean

A taxonomic study was carried out on strain 13D2W-2^T, which was isolated from a sulphur-oxidizing bacterial consortium, enriched by the deep-sea sediment of the Atlantic Ocean. The isolate was observed to be Gram-negative, oxidase- and catalase-positive, short rod-shaped and motile by means of a flagellum. Growth was observed at salinities from 0.5 to 12 % and at temperatures from 4 to 41 °C, and the strain found to be able to reduce nitrate but not degrade gelatin. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain 13D2W-2^T belongs to the genus Thioclava, with highest sequence similarity of 97.8 % to Thioclava dalianensis DLFJ1-1^T, followed by Thioclava pacifica TL 2^T (97.7 %), while the sequence similarities to other members of the genus were all below 97.0 %. The digital DNA:DNA hybridization estimated values between strain 13D2W-2^T and, respectively, T. dalianensis DLFJ1-1^T and T. pacifica TL 2^T were 22.6 ± 2.4 and 25.6 ± 2.4 %. The ANI values between strain 13D2W-2^T and T. dalianensis DLFJ1-1^T and T. pacifica TL 2^T were 78.49 and 81.91 % respectively. The principal fatty acid identified was Summed Feature 8 (C_18:1 ω7c/ω6c) (74.38 %). The isoprenoid quinone of strain 13D2W-2^T was identified as Q10 (100 %). The major polar lipids of strain 13D2W-2^T were found to be comprised of phosphatidylethanolamine, phosphatidylglycerol, an aminophospholipid, a glycolipid and three unknown phospholipids. The G+C content of the chromosomal DNA was determined to be 65.3 mol%. The combined genotypic and phenotypic data show that strain 13D2W-2^T represents a novel species of the genus Thioclava, for which the name Thioclava atlantica sp. nov. is proposed, with the type strain 13D2W-2^T ( = MCCC 1A02612^T = LMG 27145^T).