Coralliovum pocilloporae gen. nov., sp. nov. and Sanyastnella coralliicola gen. nov., sp. nov. isolated from coral tissue: proposal of two new families, Coralliovaceae fam. nov. and Sanyastnellaceae fam. nov

A genome- based polyphasic approach was used to determine the taxonomic status of two novel bacterial strains, SCSIO 12594 T and SCSIO 12813 T , isolated from tissues of a coral. Both strains were Gram- stain- negative and facultatively anaerobic. The genome sizes of strains SCSIO 12594 T and SCSIO 12813 T were 3.9 Mb and 4.1 Mb, respectively, and they possessed DNA G+C contents of 55.1 and 46.2 mol%, respectively . Both strains were found to be catalase- and oxidase- positive, while SCSIO 12594 T also could hydrolyse starch. SCSIO 12594 T was observed to grow at between 20 and 37 degrees C (optimally at 25 degrees C) and at a pH range from 6 to 7 and in the presence of 3-7 % (w/v) NaCl. The growth of SCSIO 12813 T required seawater and occurred at 20-30 degrees C (optimum, 25 degrees C), pH 5-8 (optimum, pH 6-7) and in the presence of 3-3.7 % (w/v) NaCl. The results of 16S rRNA gene - based phylogenetic analysis indicated that SCSIO 12594 T shared 92.97 % or less sequence similarity with its closest relatives Rhodobium gokarnense JA173 T and other members of the order Hyphomicrobiales . The results of 16S rRNA sequences - based phylogenetic analysis of SCSIO 12813 T indicated that Croceimicrobium hydrocarbonivorans A20 -9 T (89.34 %) was the most closely related species. SCSIO 12594 T and SCSIO 12813 T can be readily separated from their closest relatives, as indicated by the results of phylogenomic analysis, low average nucleotide indexes, average amino acid identity, digital DNA-DNA hybridisation (dDDH) similarities and associated phenotypic and chemical data. Consequently, the two coral isolates are considered to represent two novel genera and species for which the names Coralliovum pocilloporae gen. nov., sp. nov. and Sanyastnella coralliicola gen. nov., sp. nov. are proposed, the type strains are SCSIO 12594 T (= JCM 35320 T = GDMCC 1.3060 T ) and SCSIO 12813 T (= JCM 35373 T = GDMCC 1.3063 T ), respectively. In addition, two novel families, Coralliovaceae fam. nov. and Sanyastnellaceae fam. nov are proposed to accommodate Coralliovum pocilloporae gen. nov., sp. nov. and Sanyastnella coralliicola gen. nov., sp. nov., respectively.