Fulvivirga Aurantia Sp. Nov. And Xanthovirga Aplysinae Gen. Nov., Sp. Nov., Marine Bacteria Isolated From The Sponge Aplysina Fistularis, And Emended Description Of The Genus Fulvivirga

Two Gram-stain-negative, strictly aerobic, marine bacteria, designated as strains RKSG066(T) and RKSG123(T), were isolated from a sponge Aplysina fistularis collected at a depth of 15 m off the west coast of San Salvador, The Bahamas. Investigation of nearly full-length 16S rRNA gene and whole genome-based phylogenies revealed that both strains belong to the order Cytophagales within the class Cytophagia and phylum Bacteroidetes. Strain RKSG066(T) formed a monophyletic Glade with described members of the genus Fulvivirga, while strain RKSG123(T) formed a well-supported paraphyletic branch apart from this and other related genera within the family Flammeovirgaceae. For both RKSG066(T) and RKSG123(T), optimal growth parameters were 30-37 degrees C, pH 7-8 and 2-3% (w/v) NaCl; cells were catalase- and oxidase-positive, and flexirubin-type pigments were absent. The pre- dominant fatty acids were C-15:0, C-16:0, C-18:0, iso-C-17:0 3-OH, C-16:1 omega 5c, iso-C-15:0 3-OH, C-18:1 omega 9c and iso-C-15:1 G for RKSG066(T), and iso-C-17:0 3-OH, C-16:1 omega 5c, C-15:0, C-16:0 3-OH and summed feature 4 (iso-C-17:1 I and/or anteiso-C-17:1 B) for RKSG123(T). Menaquinone-7 was the major respiratory quinone for both strains. The DNA G+C contents of RKSG066(T) and RKSG123(T) were 39.5 and 36.7 mol%, respectively. On the basis of phylogenetic distinctiveness and polyphasic analysis, the type strain RKSG066(T) (=TSD-73(T)=LMG 29870(T)) is proposed to represent a novel species of the genus Fulvivirga, for which the name Fulvivirga aurantia sp. nov. is proposed. The type strain RKSG123(T) (=TSD-75(T) =LMG 30075(T)) is proposed to represent the type species of a novel genus and species with the proposed name Xanthovirga aplysinae gen. nov., sp. nov. Additionally, the genus Fulvivirga is emended to include strains of orange-pigmented colonies that contain the predominant cellular fatty acids C-16(:0), C-18:0, C-16(:1) omega 5c and C-18:1 omega 9c.