Description of 'Candidatus Marispirochaeta associata' and reclassification of Spirochaeta bajacalifomiensis, Spirochaeta smaragdinae and Spirochaeta sinaica to a new genus Sediminispirocha eta gen. nov as Sediminispirochaeta bajacalifomiensis comb. nov., Sediminispirochaeta smaragdinae comb. nov and Sediminispirochaeta sinaica comb. nov.

Strain JC231 was isolated from a coastal saline habitat of Gujarat and was identified based on 16S rRNA gene sequence analysis as a member belonging to the genus Spirocha eta and showed highest sequence similarity (<91%) with Spirochaeta bajacalifomiensis DSM 16054(T) and other members of the family Spirochaetaceae. Intensive attempts to culture strain JC231 in pure culture have failed and were associated with only one species of a Desulfovibrio. However, presence of fosmidomycin inhibited the growth of Desulfovibrio sp. and strain JC231 was characterized in its presence. Strain JC231 was an obligate anaerobe, helical shaped and Gram stain -negative with catalase and oxidase negative. Draft genome sequence analysis of strain JC231 indicated the full complement of genes for both 2-C-methyl-D-erythritol 4 -phosphate and 3-hydroxy-3-methylglutaryl-CoA pathways of terpenogenesis. C-14:0, iso-C-15:0, C-16.0, iso-C15:1H/C-13:0 3OH and iso-(14:0) are the major (>5%) fatty acids. Strain JC231 contains diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and six unidentified lipids (L1-L6). G+C content of strain JC231 was 55.7 mol%. Distinct morphological, physiological and genotypic differences from the previously described taxa support the classification of strain JC231 as a representative of a new genus and species in the family Spirochaetaceae, for which the name 'Candidatus Marispirochaeta associata' is proposed. Strain JC231 is deposited as a defined co-culture with Desulfovibrio sp. JC271 to DSMZ (DSM 29857) and KCTC (KCTC 15472). Based on phenotypic, genotypic and phylogenetic analyses, we also propose the reclassification of Spirochaeta bajacalifomiensis as Sediminispirocha eta bajacaliforniensis gen. nov., comb. nov., Spirocha eta smaragdinae as Sediminispirocha eta smaragdinae comb. nov. and Spirocha eta sinaica as Sediminispirocha eta sinaica comb. nov.