title: Description of Fabibacter halotolerans gen. nov., sp. nov. and Roseivirga spongicola sp. nov., and reclassification of [Marinicola] seohaensis as Roseivirga seohaensis comb. nov.
abstract: Bacterial strains UST030701-097T and UST030701-084T were isolated from a marine sponge in the Bahamas. Both strains were pink-pigmented, Gram-negative, strictly aerobic and chemo-organotrophic. Cells of strain UST030701-097T were short, curved rods with fast-gliding motility, whereas those of strain UST030701-084T were straight rods with a less rapid gliding motion. The two strains had MK-7 as the major respiratory quinone and did not produce flexirubin-type pigments. The DNA G+C contents of strains UST030701-097T and UST030701-084T were 42.5 and 43.7 mol%, respectively. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the two strains belonged to the family 'Flexibacteraceae' of the phylum Bacteroidetes. 16S rRNA gene sequence similarity between strains UST030701-097T and UST030701-084T was 95.0 %; their closest relative was [Marinicola] seohaensis, with 93.3 % and 96.0 % sequence similarity, respectively. Phylogenetic tree topology indicated that the two strains belonged to the same lineage, but were on separate branches. Whilst strain UST030701-084T and [Marinicola] seohaensis were found on one branch, strain UST030701-097T was in another branch that had no species with validly published names. Based on the polyphasic taxonomic data obtained in the present study, we propose that strain UST030701-097T represents a novel genus and that strain UST030701-084T represents a novel species in the phylum Bacteroidetes. The genus Fabibacter gen. nov. is proposed, with strain UST030701-097T (=NRRL B-41220T=JCM 13334T) as the type strain of the type species, Fabibacter halotolerans sp. nov. Strain UST030701-084T (=NRRL B-41219T=JCM 13337T) is proposed as the type strain of Roseivirga spongicola sp. nov. In an earlier study, it was suggested that the genus Marinicola is a later heterotypic synonym of the genus Roseivirga. However, a formal proposal to reclassify [Marinicola] seohaensis, the only member of the genus Marinicola, has not yet been made. The results of phylogenetic analyses in this study support the reclassification of [Marinicola] seohaensis as Roseivirga seohaensis comb. nov.
authors.affiliation: Coastal Marine Laboratory/Department of Biology, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR.
authors.forename: Stanley C K
authors.initials: SCK
authors.lastname: Lau
authors.affiliation: Coastal Marine Laboratory/Department of Biology, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR.
authors.forename: Mandy M Y
authors.initials: MMY
authors.lastname: Tsoi
authors.affiliation: Coastal Marine Laboratory/Department of Biology, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR.
authors.forename: Xiancui
authors.initials: X
authors.lastname: Li
authors.affiliation: Coastal Marine Laboratory/Department of Biology, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR.
authors.forename: Ioulia
authors.initials: I
authors.lastname: Plakhotnikova
authors.affiliation: Coastal Marine Laboratory/Department of Biology, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR.
authors.forename: Sergey
authors.initials: S
authors.lastname: Dobretsov
authors.affiliation: Coastal Marine Laboratory/Department of Biology, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR.
authors.forename: Madeline
authors.initials: M
authors.lastname: Wu
authors.affiliation: Department of Biology, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR.
authors.forename: Po-Keung
authors.initials: PK
authors.lastname: Wong
authors.affiliation: Center for Marine Science, University of North Carolina at Wilmington, Wilmington, NC, USA.
authors.forename: Joseph R
authors.initials: JR
authors.lastname: Pawlik
authors.affiliation: Coastal Marine Laboratory/Department of Biology, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR.
authors.forename: Pei-Yuan
authors.initials: PY
authors.lastname: Qian
mesh_terms: D000332:Aerobiosis; D000818:Animals; D015373:Bacterial Typing Techniques; D001444:Bahamas; D001482:Base Composition; D041964:Cytophagaceae / Q000145:classification* / Q000166:cytology / Q000302:isolation & purification* / Q000502:physiology; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D020459:Genes, rRNA; D005840:Gentian Violet; D008386:Marine Biology; D008969:Molecular Sequence Data; D009068:Movement; D010619:Phenazines; D010802:Phylogeny; D010860:Pigments, Biological / Q000096:biosynthesis; D011090:Polyenes / Q000032:analysis; D011161:Porifera / Q000382:microbiology*; D011809:Quinones / Q000032:analysis / Q000302:isolation & purification; D012329:RNA, Bacterial / Q000235:genetics; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA
chemical_list: D004269:DNA, Bacterial; D004275:DNA, Ribosomal; C035863:Gram's stain; D010619:Phenazines; D010860:Pigments, Biological; D011090:Polyenes; D011809:Quinones; D012329:RNA, Bacterial; D012336:RNA, Ribosomal, 16S; C017313:flexirubins; D005840:Gentian Violet