Gulosibacter chungangensis sp. nov., an actinomycete isolated from a marine sediment, and emended description of the genus Gulosibacter

Abstract

A gram-positive, strictly aerobic, non-spore-forming, irregular short rod, strain CAU 9625(T), was isolated from a sediment of the Yellow Sea in the Republic of Korea. Strain CAU 9625(T) grew optimally at 37 °C, at pH 8.0 and in the presence of 1 % (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain CAU 9625(T) belonged to the genus Gulosibacter, which has one known member, Gulosibacter molinativorax. Strain CAU 9625(T) and G. molinativorax ON4(T) shared 97.8 % 16S rRNA gene sequence similarity and formed a distinct cluster (99 % bootstrap support) within the family Microbacteriaceae. DNA-DNA relatedness between strain CAU 9625(T) and G. molinativorax DSM 13485(T) was 35.4±0.9 %. The predominant menaquinone was MK-9. The major whole-cell sugars were ribose and glucose. The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, an unidentified phospholipid and an unidentified lipid. The fatty acid composition was similar to that of G. molinativorax DSM 13485(T), with anteiso-C(15 : 0) as the predominant fatty acid. The DNA G+C content of strain CAU 9625(T) was 66.2 mol%. The phylogenetic and genetic distinctiveness and several differentiating phenotypic and chemotaxonomic properties revealed that strain CAU 9625(T) was distinguishable from G. molinativorax and other phylogenetic neighbours. On the basis of these data, strain CAU 9625(T) represents a novel species of the genus Gulosibacter, for which the name Gulosibacter chungangensis sp. nov. is proposed. The type strain is CAU 9625(T) ( = KCTC 13959(T) = CCUG 60841(T)).