Vibrio Algicola Sp. Nov., Isolated From The Surface Of Coralline Algae

A Gram-stain-negative. oxidase- and catalase-positive, facultative anaerobic and rod-shaped bacterium, designated strain SM1977(T), was isolated from the surface of coralline algae collected from the intertidal zone at Qingdao, PR China. The strain grew at 10-35 degrees C, pH 4.5-8.5 and with 1-8.5% (w/v) NaCl. It reduced nitrate to nitrite and hydrolysed Tween 20 and DNA. Phylogenetic analysis based on 165 rRNA gene sequences revealed that strain SM1977(T) was affiliated with the genus Vibrio, having the highest sequence similarity (97.6%) to the type strain of Vibrio casei, followed by those of another five species (95.6-97.6%) in the Rumoiensis Glade of the genus Vibrio. However, the in silico DNA-DNA hybridization (75.3-75.9%) and average nucleotide identity (21.6-22.8%) values of SM1977(T) against these close relatives were all below the corresponding thresholds to discriminate bacterial species. The major fatty acids were summed feature 3 (C-16:1 omega 7c and/or C-16:1 omega 6c), C-16:1 and summed feature 8 (C-18:1 omega 6c and /or C-18:1 omega 7c). The predominant polar lipids were phosphatidylethanolamine, diphosphatidylglycerol and phosphatidylglycerol. The sole respiratory quinone was Q-8. The genomic DNA G+C content of strain SM1977(T), determined from the obtained whole genomic sequence, was 42.3 mol%. On the basis of the polyphasic results obtained in this study, strain SM1977(T) is considered to represent a novel species within the genus Vibrio, for which the name Vibrio algicola sp. nov. is proposed. The type strain is SM1977(T) (=MCCC 1K04351(T)=KCTC 72847(T)).