Actinopolyspora sabaoui sp. nov., a novel halophilic actinobacterium isolated from Ghardaïa soil, Algeria

A novel halophilic actinobacterium, designated H202^T, was isolated from a Saharan soil in the Ahbès region (Béni-Isguen, Ghardaïa province, South Algeria), and its taxonomic position was determined by a genome-based polyphasic approach. Phylogenetic analysis of the 16S rRNA gene sequence revealed that the strain H202^T belonged to the genus Actinopolyspora and showed the highest sequence similarity to Actinopolyspora mzabensis DSM 45460^T (99.46%). Comparative genomic analysis based on digital DNA-DNA hybridization (dDDH), average nucleotide identity (ANI) and average amino acid identity (AAI) showed values below the recommended species cut-off thresholds of 70% (dDDH) and 95-96% (ANI and AAI), suggesting that the strain H202^T represents a novel species. This strain exhibits the typical characteristics of the genus Actinopolyspora. The cell-wall hydrolysates contained meso-diaminopimelic acid, and the diagnostic whole-cell sugars were arabinose and galactose. Phosphatidylcholine was identified as the diagnostic phospholipid, and the predominant menaquinones were MK-9(H₄) and MK-10(H₄). The major fatty acids (≥10%) were anteiso-C_17:0, iso-C_15:0, iso-C_16:0 and anteiso-C_15:0. The genome size of strain H202^T was estimated to be 5.2 Mbp, with a G+C content of 67.5%. Based on these findings, strain H202^T is proposed as a representative of a novel species within the genus Actinopolyspora, named Actinopolyspora sabaoui sp. nov. The type strain is H202^T (=DSM 46671^T=CECT 31287^T).