Polyphasic taxonomic analysis was performed to characterize a novel bacterium, which was isolated from surface sediment of the Terra Nova Bay, Antarctica, and designated as R04H25T. The cells of the isolate were Gram-stain-negative, aerobic, non-motile, slightly curved rods. Growth occurred at 4-42 °C, pH 7.0-9.5, and in 1-15 % (w/v) NaCl. Phylogenetic trees based on 16S rRNA gene sequences indicated that strain R04H25T formed an independent lineage within the genus Pseudidiomarina and its nearest neighbours were Pseudidiomarina donghaiensis 908033T (98.2 %), Pseudidiomarina marina PIM1T (98.1 %), Pseudidiomarina woesei W11T (97.8 %), Pseudidiomarina maritima 908087T (97.1 %) and Pseudidiomarina tainanensis PIN1T (97.0 %). The average nucleotide identities between strain R04H25T and the nearest neighbours were 76.2-77.7 %. The major fatty acids were iso-C17 : 0, summed feature 9, iso-C15 : 0, C16 : 0 and iso-C11 : 0 3-OH. The polar lipids comprised phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, an unidentified aminophospholipid, three unidentified glycolipids and two unidentified lipids. The predominant respiratory quinone was ubiquinone 8. The genomic DNA G+C content was 48.2 mol%. On the basis of the phylogenetic, physiological and chemotaxonomic results, we propose a novel species named as Pseudidiomarina gelatinasegens sp. nov. in the genus Pseudidiomarina, with the type strain R04H25T (=GDMCC 1.1503T=KCTC 62911T).
Keywords: Alteromonadales; Antarctica; Pseudidiomarina; marine sediment; polyphasic taxonomy.