Marinifilum albidiflavum sp. nov., isolated from coastal sediment

A novel Gram-stain-negative, facultatively anaerobic, filamentous, and yellowish-white-pigmented marine bacterium, designated strain FB208T, was isolated from marine sediment obtained off the coastal area of Weihai, China. Cells of strain FB208T were filamentous during exponential growth, fragmented to rods in the stationary growth phase and became spherical in aged cultures. It grew optimally at 33 °C, at pH 7.0-7.5 and in the presence of 2.0-3.0 % (w/v) NaCl. Based on the 16S rRNA gene sequence, strain FB208T was found to be closely related to Marinifilum flexuosum DSM 21950T (96.9 % similarity) and Marinifilum fragile JCM 15579T (96.4 %), with less than 90.0 % sequence similarity to other genera of the class Bacteroidia. Phylogenetic analysis, also based on 16S rRNA gene sequences, placed strain FB208T in the genus Marinifilum, family Marinifilaceae. The predominant isoprenoid quinone of strain FB208T was identified as menaquinone MK-7. The main cellular fatty acids were iso-C15 : 0, iso-C17 : 0 3-OH and iso-C17 : 1ω9c, and the major polar lipids were an unidentified lipid and aminophospholipid. The G+C content of the genomic DNA was 43.8 mol%. Based on these phylogenetic and phenotypic data, strain FB208T represents a novel species of the genus Marinifilum, for which the name Marinifilum albidiflavum sp. nov. is proposed. The type strain is FB208T (=KCTC 42591T=MCCC 1H00113T).