Leucobacter luti sp. nov., and Leucobacter alluvii sp. nov., two new species of the genus Leucobacter isolated under chromium stress

Two strains designated RF6T and RB10T were isolated, from activated sludge and from river sediments, respectively, both systems receiving chromium contaminated water. Phylogenetic analysis showed that strain RF6Tand strain RB10T represented two new species of the genus Leucobacter. Strain RB10T can be distinguished from RF6T by its ability to grow at 37 °C, by showing a different optimum pH, by cell wall amino acids different relative amount and by having the fatty acid strait C16:0 as the third most abundant fatty acid. On the basis of the distinct peptidoglycan composition, 16S ribosomal DNA sequence analysis, DNA–DNA reassociation values, and phenotypic characteristics we are of the opinion that strain RF6T represents a new species of the genus Leucobacter for which we propose the name Leucobacter luti (CIP 108818T=LMG 23118) and that strain RB10T represents an additional new species of the same genus for which we propose the name Leucobacter alluvii (CIP 108819T=LMG 23117).