Paenibacillus selenitireducens sp. nov., a selenite-reducing bacterium isolated from a selenium mineral soil

Abstract

A Gram-stain-positive, rod-shaped, facultatively anaerobic bacterium, designated strain ES3-24T, was isolated from a selenium mineral soil. The isolate was endospore-forming, nitrate-reducing and motile by means of peritrichous flagella. The major menaquinone was menaquinone 7 (MK-7) and the predominant fatty acids (>5 %) were anteiso-C15 : 0, iso-C16 : 0, C16 : 0 and anteiso-C17 : 0. The major polar lipids were diphosphatidylglycerol, phosphatidylethanolamine and two unknown aminophospholipids. Strain ES3-24T contained meso-diaminopimelic acid in the cell-wall peptidoglycan and the DNA G+C content was 49.6 mol%. According to phylogenetic analysis based on the 16S rRNA gene sequence, strain ES3-24T was most closely related to Paenibacillus terrigena A35T, with 16S rRNA gene sequence identity of 98.3 %, while the other members of the genus Paenibacillus had 16S rRNA gene sequence identities of less than 95.0 %. DNA–DNA relatedness between strain ES3-24T and P. terrigena CCTCC AB206026T was 39.3 %. In addition, strain ES3-24T showed obvious differences from closely related species in major polar lipids, nitrate reduction and other physiological and biochemical characteristics. The data from our polyphasic taxonomic study reveal that strain ES3-24T represents a novel species of the genus Paenibacillus , for which the name Paenibacillus selenitireducens sp. nov. is proposed. The type strain is ES3-24T ( = KCTC 33157T = CCTCC AB2013097T).