Planomicrobium iranicum sp. nov., a novel slightly halophilic bacterium isolated from a hypersaline wetland.

A novel strain, designated as MX6 was isolated from Meighan wetland, in the centre of Iran. The cells were Gram-stain-positive, motile, coccoid to rod-shaped, oxidase- and catalase-positive. The strain grew optimally at 35 °C, 3 % (w/v) NaCl and pH 7-7.5. A polyphasic taxonomic study was undertaken in order to characterize the strain in detail. The results of phylogenetic analysis based on 16S rRNA gene sequences indicated that MX6 represented a member of the phylum Firmicutes, family Planococcaceae, genus Planomicrobium, and showed the highest similarity with Planomicrobium flavidum ISL-41 (98.2 %) and Planomicrobium psychrophilum CMC 53or (98.0 %). The main polar lipids of MX6 consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and seven unidentified phospholipids and its DNA G+C content was 45.5 mol%. Major cellular fatty acids were anteiso-C15 : 0, C16 : 1ω7c alcohol, iso-C14 : 0, iso-C15 : 0 and iso-C16 : 0 and the predominant respiratory quinone was Q-8 (62 %). Experimental DNA-DNA hybridization between MX6 and Planomicrobium flavidum IBRC-M 11047 was 20 %, supporting the differential taxonomic status of MX6 as representing a different taxon. All these data indicate that MX6 represents a novel species of the genus Planomicrobium, for which the name Planomicrobium iranicum sp. nov. is proposed. The type strain is MX6 (=IBRC M 10928=LMG 28548).