Abstract
A strictly aerobic, Gram-stain-negative, non-motile, rod-shaped bacterium, designated strain R1DC9(T), was isolated from sediments of a mangrove stand on the Red Sea coast of Saudi Arabia via diffusion chamber cultivation. Strain R1DC9(T) grew at 20-40 degrees C (optimum, 37 degrees C), pH 6-10 (optimum, pH 8) and 3-11% NaCl (optimum, 7-9%) in the cultivation medium. The genome of R1DC9(T) was 4661901 bp long and featured a G+C content of 63.1 mol%. Phylogenetic analyses based on the 16S rRNA gene sequence and whole-genome multilocus sequence analysis using 120 concatenated single-copy genes revealed that R1DC9(T) represents a distinct lineage in the order Cytophagales and the phylum Bacteroidetes separated from the Roseivirgaceae and Marivirgaceae families. R1DC9(T) displayed 90 and 89% 16S rRNA gene sequence identities with Marivirga sericea DSM 4125(T) and Roseivirga ehrenbergii KMM 6017(T) , respectively. The predominant quinone was MK7. The polar lipids were phosphatidylethanolamine, two unknown phospholipids and two unknown lipids. The predominant cellular fatty acids were the saturated branch chain fatty acids iso-C-15 : 0, iso-C-17 : 0 3-OH and iso-C-17 : 0, along with a low percentage of the monounsaturated fatty acid C-16 : 1 omega 5c. Based on differences in phenotypic, physiological and biochemical characteristics from known relatives, and the results of phylogenetic analyses, R1DC9(T) (=KCTC 72349(T)=JCM 33609(T)=NCCB 100698(T)) is proposed to represent a novel species in a new genus, and the name Mangrovivirga cuniculi gen. nov., sp. nov. is proposed. The distinct phylogenetic lineage among the families in the order Cytophagales indicates that R1DC9(T) represents a new family for which the name Mangrovivirgaceae fam. nov. is proposed.