Citricoccus alkalitolerans sp. nov., a novel actinobacterium isolated from a desert soil in Egypt

Abstract

An actinobacterium, strain YIM 70010T, which was isolated from a desert soil sample collected in Egypt, was subjected to a polyphasic taxonomy study. The organism was alkalitolerant and its optimum growth occurred at pH 8·0–9·0. The isolate contained chemotaxonomic markers that were characteristic of the genus Citricoccus, i.e. the peptidoglycan type Lys–Gly–Glu (variation A4α), the predominant menaquinone MK-9(H2) and a polar lipid profile consisting of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol and two unknown glycolipids. The major fatty acids were anteiso-C15 : 0 and iso-C15 : 0. The G+C content of the genomic DNA was 63·8 mol%. Strain YIM 70010T exhibited a 16S rRNA gene sequence similarity of 99·6 % and DNA–DNA relatedness value of 56 % with Citricoccus muralis DSM 14442T. The phenotypic characteristics and DNA–DNA relatedness data indicate that strain YIM 70010T can be distinguished from C. muralis (DSM 14442T). Therefore, on the basis of the polyphasic taxonomic data presented, a novel species of the genus Citricoccus, Citricoccus alkalitolerans sp. nov. (type strain, YIM 70010T=CCTCC AA 203008T=DSM 15665T=KCTC 19012T) is proposed.