Actinopolyspora righensis sp. nov., a novel halophilic actinomycete isolated from Saharan soil in Algeria

Abstract

A novel halophilic actinomycete strain, H23T, was isolated from a Saharan soil sample collected in Djamaˆa (Oued Righ region), El-Oued province, South Algeria. Strain H23T was identified as a member of the genus Actinopolyspora by a polyphasic approach. Phylogenetic analysis showed that strain H23T had 16S rRNA gene sequence similarities ranging from 97.8 % (Actinopolyspora xinjiangensis TRM 40136T) to 94.8 % (Actinopolyspora mortivallis DSM 44261T). The strain grew optimally at pH 6.0–7.0, 28–32°C and in the presence of 15–25 % (w/v) NaCl. The substrate mycelium was well developed and fragmented with age. The aerialmyceliumproduced long, straight or flexuous spore chains with non-motile, smooth-surfaced and rod-shaped spores. Strain H23T had MK-10 (H4) and MK-9 (H4) as the predominant menaquinones. The whole microorganism hydrolysates mainly consisted of meso-diaminopimelic acid, galactose and arabinose. The diagnostic phospholipid detected was phosphatidylcholine. The major cellular fatty acids were anteiso-C17:0 (37.4 %), iso-C17:0 (14.8 %), iso-C15:0 (14.2 %), and iso-C16:0 (13.9 %). The genotypic and phenotypic data show that the strain represents a novel species of the genus Actinopolyspora, for which the name Actinopolyspora righensis sp. nov. is proposed, with the type strain H23T (=DSM 45501T = CCUG 63368T = MTCC 11562T).