Janibacter alittae sp. nov., an actinobacterium isolated from the gut of marine sandworm (Alitta virens).

Abstract

A novel Gram-stain-positive, facultatively anaerobic, non-motile, catalase-positive, oxidase-negative and ovoid cocci, designated as A1S7^T, was isolated from the gut of a marine sandworm (Alitta virens). Strain A1S7^T exhibited optimal growth at temperatures of 20-30 ℃, pH 6-8 and in the presence of 2-4% (w/v) NaCl. Phylogenetic analysis based on the 16S rRNA gene sequence indicated that strain A1S7^T belonged to the genus Janibacter, exhibiting a similarity of 99.0% to Janibacter cremeus KCTC 49873^T, followed by Janibacter anophelis KCTC 19282^T (98.8%), Janibacter hoylei KCTC 49872^T (98.4%), Janibacter limosus KACC 20518^T (98.2%) and Janibacter corallicola KACC 21120^T (97.2%). The complete genome sequence of strain A1S7^T revealed a genome size of 3360920 bp with a genomic G+C content of 70.1 mol%. The orthologous average nucleotide identity and the digital DNA-DNA hybridization values between strain A1S7^T and Janibacter cremeus KCTC 49873^T were determined to be 89.5 and 37.2%, respectively. The major respiratory quinone was MK-8(H₄). The predominant fatty acids (>10%) included iso-C_16:0, C_17:1  ω8c, C_18:1  ω9c and C_17:0. Polar lipids comprised diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol, one unknown phosphoglycolipid and three unknown polar lipids. The cell-wall peptidoglycan type was A1γ. The major whole-cell sugars were ribose, mannose and glucose. Based on phenotypic, phylogenetic, genotypic and chemotaxonomic properties, strain A1S7^T represents a novel species in the genus Janibacter, for which the name Janibacter alittae sp. nov. is proposed. The type strain is A1S7^T (=KCTC 49714^T = JCM 36706^T).