Pseudodonghicola flavimaris sp. nov. and Sedimentitalea xiamensis sp. nov., two novel species belonging to the family Roseobacteraceae

Two Gram-stain-negative, chemoheterotrophic, aerobic bacteria, designated IC7 T and JM2-8 T , were isolated from seawater of the Yellow Sea of China and rhizosphere soil of mangroves in Xiamen, Fujian, respectively. Phylogenetic analyses based on 16S rRNA gene and genome sequences showed that these two novel strains belonged to the family Roseobacteraceae . Strain IC7 T formed a coherent lineage within the genus Pseudodonghicola , showing 98.05 % 16S rRNA gene sequence similarity to Pseudodonghicola xiamenensis Y-2 T . Strain JM2-8 T was most closely related to members of the genus Sedimentitalea , showing 96.51 and 96.73 % 16S rRNA gene sequence similarities to Sedimentitalea nanhaiensis NH52F T and Sedimentitalea todarodis KHS03 T , respectively. The two novel strains contained Q-10 as the major quinone, and phosphatidylethanolamine, aminophospholipid, phosphatidylglycerol and phosphatidylcholine as the principal polar lipids. The main fatty acid of strain IC7 T was C 19 : 0 cyclo ω 8 c , while the fatty acid profile JM2-8 T was dominated by summed feature 8 containing C 18 : 1 ω 7 c and/or C 18 : 1 ω 6 c . The average nucleotide identity and digital DNA–DNA hybridization values between these two novel isolates and their closely related species were below the cut-off values of 95–96 and 70 %, respectively. The combined genotypic and phenotypic data show that strain IC7 T represents a novel species of the genus Pseudodonghicola , for which the name Pseudodonghicola flavimaris sp. nov. is proposed, with the type strain IC7 T (=MCCC 1A02763 T =KCTC 82844 T ), and strain JM2-8 T represents a novel species of the genus Sedimentitalea , for which the name Sedimentitalea xiamensis sp. nov. is proposed, with the type strain JM2-8 T (=MCCC 1A17756 T =KCTC 82846 T ).