Agaribacter flavus sp. nov., isolated from red algae.

A Gram-stain-negative, non-motile, aerobic, curved-rod bacterium, designated as strain 2p52, was isolated from the marine algae Gracilaria blodgettii collected off the coast of Lingshui county, in Hainan province, China. Strain 2p52 grew at 15-42 °C (optimally at 30-33 °C), at pH 6.0-10.0 (7.5-8.0) and in the presence of 1.0-8.0 % (w/v) NaCl (2.0-3.0 %). The most closely related species was Agaribacter marinus (96.5 % 16S rRNA gene sequence similarity). Phylogenetic analysis based on the sequence of the 16S rRNA gene revealed that strain 2p52 belonged to the genus Agaribacter. The novel strain contained phophatidylethanolamine and phosphatidylglycerol as the major polar lipids. The predominant isoprenoid quinine was Q-8, and the DNA G+C content was 43.2 mol%. The major cellular fatty acids were C16 : 1ω7c and/or iso-C15 : 0 2-OH, C16 : 0, and C18 : 1ω7c. The phenotypic and systematic comparative analyses indicated that the isolate is representative of a novel species of the genus Agaribacter, and the name Agaribacter flavus sp. nov. is proposed. The type strain is 2p52 (=KCTC 52473=MCCC 1H00151).