Maribacter algarum sp. nov., a new member of the family Flavobacteriaceae isolated from the red alga Gelidium amansii

A Gram-stain-negative, rod-shaped (0.2–0.3×1.0-2.4 µm), catalase-positive, oxidase-negative and non-motile bacterium, designated strain RZ26 T , was isolated from the marine red algae collected from the coast of Weihai, PR China. Growth of strain RZ26 T occurred at 15–33 °C (optimum, 25–28 °C), pH 6.0–9.5 (optimum, pH 7.0–7.5) and 0.5–5.0 % (w/v) NaCl (optimum, 2.0–3.0 %). Resuls of phylogenetic analysis based on 16S rRNA gene sequences showed that strain RZ26 T was most closely related to Maribacter spongiicola DSM 25233 T (96.2 % sequence similarity), followed by Maribacter forsetii DSM 18668 T (96.1 %) and Maribacter vaceletii DSM 25230 T (95.4 %). The average nucleotide identity and the average amino acid identity values between strain RZ26 T and M. sedimenticola KCTC 12966 T , M. spongiicola DSM 25233 T , M. vaceletii DSM 25230 T and M. forsetii DSM 18668 T were 75.6, 76.2, 76.0, 76.7, 64.3, 63.9, 68.6 and 68.0 %, respectively. The digital DNA–DNAhybridization values based on the draft genomes between strain RZ26 T and M. sedimenticola KCTC 12966 T , M. spongiicola DSM 25233 T and M. vaceletii DSM 25230 T were 38.0, 35.1 and 37.1 %, respectively. The major fatty acids in strain RZ26 T were iso-C 17 : 0 3-OH, iso-C 15 : 0 and C 16 : 1  ω 7 c /C 16 : 1  ω 6 c . The major respiratory quinone was MK-6. The dominant polar lipid was phosphatidylethanolamine. The DNA G+C content was 38.0 mol%. Phylogenetic analysis shows strain RZ26 T fell within a clade comprising species of the genus Maribacter . Polyphasic taxonomy indicates that the isolate represents a novel species of the genus Maribacter , for which the name Maribacter algarum sp. nov. is proposed, with type strain RZ26 T (=KCTC 62992 T =MCCC 1H00362 T ).