Roseicyclus marinus sp nov., isolated from a Synechococcus culture, and emended description of the genus Roseicyclus

A novel Gram-stain-negative, aerobic, non-flagellated, pink-pigmented and rod-shaped strain with gliding motility, designated strain CCMM001(T), was isolated from a mixed culture of Synechococcus species PCC7002 and a natural bacterial community from a sample of offshore seawater from Qingdao, China, during September 2014. The strain contained bacteriochlorophyll a with a small peak at 802nm and a large in vivo absorption band at 870 nm. Strain CCMM001(T) grew optimally at pH 7.0 and 30 degrees C in the presence of 3% (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain CCMM001(T) is most closely related to the genus Roseicyclus and its type and only species Roseicyclus mahoneyensis ML6(T) with 96.9% sequence similarity. The polar lipids of strain CCMM001(T) consisted of phosphatidylethanolamine, phosphatidylcholine, one unidentified aminolipid, and five unidentified lipids. The predominant isoprenoid quinone was Q-10. The major fatty acids included C-18 : 1 omega 7c and C(19 : 0)cyclo omega 8c. The DNA G+C content of strain CCMM001(T) was 63.5 mol%. These phylogenetic, physiological and chemotaxonomic data indicated that strain CCMM001(T) represents a novel species of the genus Roseicyclus, for which the name Roseicyclus marinus sp. nov. is proposed. The type strain is CCMM001(T) (= MCCC 1K03242(T) = KCTC 52641(T)).