Brevibacterium litoralis sp. nov., a cellulose-degrading strain isolated from marine surface sediment.

Abstract

A Gram stain-positive, non-spore-forming, non-motile, short-rod actinomyces strain GXQ1321T was isolated from maritime surface sediments in Beihai (21° 41' 21.65″ N, 109° 05' 76.56″ E), Guangxi Zhuang Autonomous Region, and a number of categorization studies were performed. Following a period of 72h of incubation at a temperature of 30°C within a modified actinomycete culture medium, the colony was light-yellow, circular, smooth, central bulge, convex, opaque, with a 1.2-2.3mm diameter. Strain GXQ1321T had the ability to degrade cellulose. Chemotaxonomic studies revealed that the major methylnaphthoquinones in strain GXQ1321T was MK-8(H2). The most prevalent cellular fatty acids were anteiso-C19:0, anteiso-C15:0, anteiso-C17:0, and iso-C16:0. The whole-cell sugars of the strain GXQ1321T were identified rhamnose, xylose and glucose. Meso-diaminopimelic acid was found in the peptidoglycan hydrolysate, and the polar lipids were identified as diphosphatidylglycerol, three phosphoglycolipid, phosphatidylglycerol and two unknown glycolipid. This strain had 69.6% DNA G+C content. Strain GXQ1321T is classified as Brevibacterium based on its 16S rRNA gene sequence. It is closely related to Brevibacterium samyangense SST-8T (96.8%) and Brevibacterium rongguiense 5221T (96.3%). The average nucleotide identity (ANI) values of GXQ1321T and the above two type strains were 73.9-77.1%, and the digital DNA-DNA hybridisation (dDDH) values were 15.3-21.1%. Based on the phylogenetic, chemotaxonomic and physiological data, strain GXQ1321T was considered to be a novel species of the genus Brevibacterium, named Brevibacterium litoralis sp. nov, with the type strain GXQ1321T (= MCCC 1K08964T = KCTC 59167T).