Aquaticitalea lipolytica gen. nov., sp. nov., isolated from Antarctic seawater.

ABSTRACT

A Gram-stain-negative, rod-shaped bacterium, designated Ar-125T, was isolated from Antarctic seawater. It produced carotenoid-like pigments and did not produce Bchl a. Ar-125T was positive for hydrolysis of DNA, aesculin, gelatin, starch, Tween 40 and Tween 60. The sole respiratory quinone was MK-6. The major polar lipids were phosphatidylethanolamine, one unidentified aminolipid, one unidentified glycolipid and two unidentified lipids. The principal fatty acids were branched-chain fatty acids, including iso-C15 0, iso-C15 1 G, summed feature 3 (iso-C15 0 2-OH and/or C16 1ω7c), iso-C16 0, iso-C17 0 3-OH, iso-C16 0 3-OH and iso-C15 0 3-OH, as well as C15 0. The genomic DNA G+C content was 31.8 mol%. On the basis of 16S rRNA gene sequence analysis, Ar-125T is closely related to the species of the genera Bizionia(with 16S rRNA gene pairwise sequence similarity of 93.7-96.5 %), Formosa(94.3-95.8 %), Gaetbulibacter(94.2-95.7 %), Geojedonia(95.5 %), Gelidibacter (93.3-95.4 %), Meridianimaribacter(95.3 %) and Psychroserpens (94.8-95.3 %), of the family Flavobacteriaceae. Phylogenetic analysis indicated that it represented an independent lineage and that the closest relatives were members of the genus Gelidibacter. Differential phenotypic properties and chemotaxonomic differences, together with phylogenetic distinctiveness, revealed that Ar-125T could be differentiated from members of closely related genera. Therefore, it is proposed that Ar-125T represents a novel species in a new genus, for which the name Aquaticitalea lipolytica gen. nov., sp. nov. (type strain Ar-125T =CGMCC 1.15295T =JCM 30876T) is proposed.