Geodermatophilus africanus sp. nov., a halotolerant actinomycete isolated from Saharan desert sand.

A novel Gram-strain positive, aerobic, actinobacterial strain, designated CF11/1(T), was isolated from a sand sample obtained in the Sahara Desert, Chad. The black-pigmented isolate was aerobic and exhibited optimal growth from 25 to 35 °C at pH 6.0-8.0 and with 0-8 % (w/v) NaCl, indicating that it is a halotolerant mesophile. Chemotaxonomic and molecular characteristics of the isolate matched those described for members of the genus Geodermatophilus. The G+C content in the genome was 74.4 mol%. The peptidoglycan contained meso-diaminopimelic acid as diagnostic diaminoacid. The main phospholipids were diphosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol and a minor fraction of phosphatidylglycerol; MK-9(H4) was the dominant menaquinone, and galactose was detected as a diagnostic sugar. The major cellular fatty acid was branched-chain saturated acid iso-C16:0. Analysis of 16S rRNA gene sequences showed 95.3-98.6 % pairwise sequence identity with the members of the genus Geodermatophilus. Based on phenotypic and chemotaxonomic properties, as well as phylogenetic distinctiveness, the isolate represents a novel species, Geodermatophilus africanus, with the type strain CF11/1(T) (DSM 45422 = CCUG 62969 = MTCC 11556).