A taxonomic study was carried out on a novel bacterium, designated strain ck-I2-15T, which was
isolated from deep-sea sediment collected from the South-west Indian Ocean Ridge. Cells of
strain ck-I2-15T were Gram-reaction-negative, rod-shaped, non-motile, moderately halophilic and
capable of denitrification. Growth was observed with 0–9% (w/v) NaCl and at temperatures of
10–37 6C. The novel strain was unable to degrade gelatin. The dominant cellular fatty acids were
iso-C15 : 0, iso-C17 : 0 3-OH and summed feature 9 (iso-C17 : 1v9c and/or 10-methyl C16 : 0). The
major respiratory quinone was MK6 and the polar lipid profile comprised phosphatidylethanolamine,
one unidentified phospholipid, two unidentified aminolipids, one unidentified glycolipid and four
other unidentified lipids. The G+C content of the genomic DNA was 38 mol%. 16S rRNA gene
sequence comparison indicated that strain ck-I2-15T was most closely related to Galbibacter
mesophilus Mok-17T (92.9%sequence similarity), followed by ‘Joostella atrarenae’ M1-2 (92.8 %),
Joostella marina En5T (92.7 %) and Zhouia amylolytica HN-171T (91.6 %). Phylogenetic analyses
based on 16S rRNA gene sequences showed that strain ck-I2-15T formed a clade with the genus
Galbibacter, within the family Flavobacteriaceae. Several phenotypic properties allowed strain ck-
I2-15T to be distinguished from its closest phylogenetic relatives. On the basis of the phenotypic
and phylogenetic data, strain ck-I2-15T represents a novel species of the genus Galbibacter, for
which the name Galbibacter marinus is proposed. The type strain is ck-I2-15T (5CCTCC AB
209062T5LMG 25228T5MCCC 1A03044T).