Prauserella isguenensis sp. nov., a halophilic actinomycete isolated from desert soil

Abstract

Two actinomycete strains, designated H225T and H137, were isolated from two soil samples collected from the arid region of Ahbas at Béni-Isguen (Mzab), located in the Algerian Sahara. Phylogenetic analyses based on 16S rRNA gene sequences indicated that the novel strains should be assigned to the genus Prauserella of the family Pseudonocardiaceae , and they were therefore subjected to a polyphasic taxonomic study. These two strains contained meso-diaminopimelic acid as the diagnostic diamino acid and arabinose and galactose as major whole-cell sugars. The diagnostic phospholipid was phosphatidylethanolamine. The predominant menaquinone was MK-9(H4), and the major fatty acid was iso-C16 : 0. DNA–DNA hybridization values between strain H225T and its closest phylogenetic neighbours, namely Prauserella flava DSM 45265T, Prauserella alba DSM 44590T, Prauserella aidingensis DSM 45266T, Prauserella salsuginis DSM 45264T and Prauserella sediminis DSM 45267T, were clearly below the 70 % threshold used for species delineation. The genomic DNA G+C content of strains H225T and H137 was 70.4 mol%. On the basis of phenotypic and genotypic data, strains H225T and H137T are considered to represent a novel species of the genus Prauserella , for which the name Prauserella isguenensis sp. nov. is proposed. The type strain is H225T ( = DSM 46664T = CECT 8577T).