Brevibacterium spongiae sp. nov., isolated from marine sponge Hymeniacidon sp.

Abstract

A novel bacterial strain, designated as WHS-Z9T, was isolated from marine sponge Hymeniacidon sp. collected from Weihai (37° 25' N, 121° 58' E), Shandong Province, PR China. Cells of strain WHS-Z9T were Gram-stain-positive, non-spore-forming, non-motile, short-rod-shaped and light yellow-pigmented. The strain could grow at 10-40 °C (optimum, 20 °C), pH 4.5-9.5 (optimum, pH 8.5) and 2-14 % (w/v) NaCl (optimum, 4 %). The 16S rRNA gene sequence of strain WHS-Z9T showed 98.7 % similarity to that of Brevibacterium epidermidis NBRC 14811T, 98.5 % to Brevibacterium sediminis FXJ8.269T and 98.4 % to Brevibacterium oceani BBH7T. The phylogenetic tree based on 16S rRNA gene sequences revealed that strain WHS-Z9T was clustered with Brevibacterium limosum o2T. The whole genome of WHS-Z9T was approximately 4 217 721 bp in size with a G+C content of 65.2 %. The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values among WHS-Z9T and other Brevibacterium type strains were 83.3-85.5 % (ANI based on blast), 86.4-87.9 % (ANI based on MUMmer) and 41.9-57.5 % (dDDH). Percentage of conserved protein values between the genomes of strain WHS-Z9T and members of genera Brevibacterium were 76.8-82.9 %, while the average amino acid identity (AAI) values were 83.7-87.0 %. The dDDH, ANI, AAI and POCP values were below the standard cut-off criteria for the delineation of bacterial species. The sole respiratory quinone in strain WHS-Z9T was MK-8(H2), and the predominant fatty acids were anteiso-C15 : 0 and anteiso-C17 : 0. The major polar lipids of WHS-Z9T consisted of diphosphatidylglycerol and glycolipid. The diagnostic cell-wall diamino acid of strain WHS-Z9T was meso-diaminopimelic acid. Based on the data obtained in this study, strain WHS-Z9T (=MCCC 1K07845T=KCTC 49848T) should be classified as the type strain of a novel species of the genus Brevibacterium, for which the name Brevibacterium spongiae sp. nov. is proposed.