Mycetocola spongiae sp. nov., isolated from deep-sea sponge Cacospongia mycofijiensis

A novel bacterial strain (MSC19(T)) was isolated from a deep-sea sponge Cacospongia mycofijiensis collected in the Mariana Trench at a depth of 2681 m. The cells of the new isolate were Gram-stain-positive, non-motile, oxidase- and catalase-positive, rod-shaped and yellow-coloured. They could grow at 4-32 degrees C (optimum, 28 degrees C), pH 5.5-12 (optimum, pH 7.0) and with 0-12% (w/v) NaCl (optimum, 4%). The strain's 165 rRNA gene sequence showed 98.41% similarity to that of Mycetocola saprophilus CM-01(T). Phylogenetic analysis further suggested that strain MSC19(T) represents a new species within the genus Mycetocola. The total genome of MSC19(T) was approximately 3196754 by in size with a G+C content of 66.43 mol%. The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values among MSC19(T) and other Mycetocola type strains were 70.35-75.37% (ANIb), 83.79-84.73% (ANIm) and 20.3-21.7% (dDDH). The major fatty acids of MSC19(T) were composed of anteiso-C-15:0, iso-C-16(:0) and anteiso-C-17:0, and its predominant menaquinones were MK-10 and MK-9. The polar lipids of MSC19(T) mainly consisted of diphosphatidylglycerol, phosphatidylglycerol and glycolipid. The diagnostic cell-wall diamino acid was lysine. Combined molecular, physiological, biochemical and chemotaxonomic analyses suggest that strain MSC19(T) represents a novel species of the genus Mycetocola, for which the name Mycetocola spongiae sp. nov. is proposed. The type strain is MSC19(T) (=MCCC 1K06265(T)=KCTC 49701(T)).