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A taxonomic study was carried out on strain P73T, which was isolated from deep-sea sediment of Indian Ocean with PAHs-degrading enrichment.The bacterium was Gram-negative, oxidase and catalase positive, rod shape, nonmotile.Growth was observed at salinities from 0.5 to 12 % and at temperatures from 10 to 41 ℃.Phylogenetic analysis based on 16S rRNA gene sequences showed that strain P73T formed a clade with the genus Celeribacter and Huaishuia within the family Rhodobacteraceae, with highest sequence similarity 96.98% to Celeribacter neptunius H14T, followed by Huaishuia halophile ZXM137T (96.42%).It can degrade biphenyl, naphthalene, 2-methynaphthalene, 2,6-dimethynaphthalene, acenaphthene, anthracene, phenanthrene, dibenzothiophene,dibenzofuran, fluorene, 4-methyldibenzothiophene and fluoranthene, but not pyrene or chrysene.To get insight into the mechanism of biodegradation, the metabolites of fluoranthene degradation were examined with GC-MS.Acenaphthylene-1(2H)-one, acenaphthenequinone, 1,2-dihydroxyacenaphthylene and 1,8-naphthalic anhydride were detected as the main intermediates, indicating that the degradation of fluoranthene was initiated by dioxygenation at the C-7,8 positions.The principal fatty acids of strain P73T were Sum In Feature 8 (C18:1ω7c/ω6c) (58.6 %), Ci9:0ω8c cyclo (17.4 %) and C16:0 (7.9 %).The respiratory quinone was Q10 (100 %).The lipids were phosphatidylglycerol (PG), aminolipid (AL), two phospholipids (PL), glycolipid (GL) and one unknown lipid (L).The G+C content of the chromosomal DNA was 66.0 mol%.The combined genotypic and phenotypic data show that strain P73T represents a novel species of the genus Celeribacter, for which the name Celeribacter indica sp.nov.is proposed, with the type strain P73T.Phylogenetic study and existing phenotypic information also show that Huaishuia halophila should be transferred to the genus Celeribacter as Celeribacter halophila comb.nov.(type strain ZXM137T =CGMCC 1.8891T =LMG 24854T).