Leucobacter edaphi sp. nov., a highly chromate-tolerant bacterium isolated from chromium containing chemical plant soil.

A Gram-positive, aerobic, rod-shaped non-motile, non-sporulating bacterium, designated CSA2, was isolated from chromium-containing soils collected from a chemical plant. The 16S rRNA gene sequence of strain CSA2 showed the highest homology with Leucobacter chromiireducens subsp. solipictus (97.85%), Leucobacter chromiireducens subsp. chromiireducens (97.85%). The digital DNA-DNA hybridization (dDDH), average nucleotide identity (ANI) and the amino acid identity (AAI) values among strains CSA2 and the selected Leucobacter species were 20.6-23.4% (dDDH), 72.67-78.03% (ANI) and 66.39-76.16% (AAI), falling below the recommended thresholds for species delimitation. The principal fatty acids were anteiso-C, iso-C and anteiso-C. The polar lipids were phosphatidylglycerol, diphosphatidylglycerol and an unknown glycolipid. The major menaquinones detected were MK-10 and MK-11. The cell-wall amino acids included 2,4-diaminobutyric acid, threonine, glutamic acid, alanine and glycine. Based on molecular feature, phenotypic and chemotaxonomic, strain CSA2 was considered to be a novel species of the genus Leucobacter., and the name Leucobacter edaphi sp. nov. is proposed. The type strain is CSA2 (= JCM 34360 = CGMCC 1.18747).