A novel genus of the class Actinobacteria, Longivirga aurantiaca gen. nov., sp nov., isolated from lake sediment

A novel actinobacterial strain, designated X5(T), was isolated from the sediment of Taihu Lake in China and was subjected to a polyphasic taxonomic characterization. The strain formed orange-red colonies comprising aerobic, Gram-stain-negative, rodshaped cells on R2A agar. Phylogenetic analysis based on the 16S rRNA gene sequences revealed that the organism was closely related to the genus Sporichthya and consistently formed a distinct Glade along with the members of this genus. The closest phylogenetic neighbour was Sporichthya polymorpha NBRC 12702(T) with 93.7 % 16S rRNA gene sequence similarity. The major fatty acids (>10 %) were iso-C-16:0(18.7 %), C-18:1 omega 9c (18.6 %) and C-17:1 omega 8c (14.0 %). The genomic DNA G+C content was 74.4 mol%. The organism contained menaquinone MK-8(H-2), MK-9(H-4) and an unidentified menaquinone. Polar lipids were composed of phosphatidylglycerol, an unidentified lipid, two unidentified phospholipids and two unidentified aminolipids. The whole-cell sugars contained ribose, xylose, mannose, glucose and galactose. The cell-wall peptidoglycan contained LL-diaminopimelic acid. Based on the physiological, biochemical and chemotaxonomic data, the organism is proposed to represent a novel genus and species, for which the name Longivirga aurantiaca gen. nov., sp. nov. is proposed. The type strain is X5(T) (=CGMCC 4.7317(T)=NBRC 112237(T)).