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
Stacey R. Goldberg, Hebelin Correa, Bradley Haltli, Russell G. Kerr
Abstract
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 clade 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 °C, pH 7–8 and 2–3 % (w/v) NaCl; cells were catalase- and oxidase-positive, and flexirubin-type pigments were absent. The predominant fatty acids were iso-C 15 : 0 , C 16 : 0 , C 18 : 0 , iso-C 17 : 0 3-OH, C 16 : 1 ω5 c , iso-C 15 : 0 3-OH, C 18 : 1 ω9 c and iso-C 15 : 1 G for RKSG066 T , and iso-C 17 : 0 3-OH, C 16 : 1 ω5 c , iso-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 ω 5 c and C 18 : 1 ω 9 c .