Mesoflavibacter aestuarii sp. nov., a zeaxanthin-producing marine bacterium isolated from seawater.

An orange, rod-shaped, Gram-reaction-negative, aerobic and gliding bacterial strain devoid of flagella, designated strain KYW614(T), was isolated from seawater collected from Gwangyang Bay, Republic of Korea. Zeaxanthin was the major carotenoid pigment produced and flexirubin-type pigments were not produced. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain KYW614(T) belonged to the family Flavobacteriaceae and it was most closely related to Mesoflavibacter zeaxanthinifaciens TD-ZX30(T) (96.5%, sequence similarity). The predominant cellular fatty acids of strain KYW614(T) were iso-C(15 : 1) G (10.5%), summed feature 3 (C(16 : 1)ω7c/C(16 : 1)ω6c; 10.0%), iso-C(15 : 0) (9.5%), C(15 : 0) (7.5%) and iso-C(17 : 0) 3-OH (7.4%). MK-6 was the only isoprenoid quinone and the DNA G+C content was 32.6 mol%. Data from a polyphasic taxonomic study suggested that the isolate represents a novel species in the genus Mesoflavibacter, for which the name Mesoflavibacter aestuarii sp. nov. is proposed. The type strain is KYW614(T) ( = KCTC 32269(T) = JCM 19524(T)).