Glaciimonas singularis sp. nov., isolated from a uranium mine wastewater treatment plant.

A bacterial strain, A2-57(T), recovered from a water sample collected in a uranium mine was taxonomically studied in detail. This strain was a Gram-reaction-negative, rod-shaped bacterium that grew optimally at 25 °C and at pH 6.0-7.0 and had a DNA G+C content of 55.0 mol%. Ubiquinone 8 (UQ-8) was the predominant respiratory quinone and the major fatty acids were C16:0, C17:0 cyclo, summed feature 3 (C16:1ω6c and/or ω7c and/or C15:0 iso 2-OH) and C18:1ω7c. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain A2-57(T) belonged to the family Oxalobacteraceae and formed a distinct branch with Glaciimonas immobilis Cr9-30(T). Strain A2-57(T) shared approximately 97.3% 16S rRNA sequence similarity with G. immobilis Cr9-30(T) and also showed high sequence similarity with members of the genera Herbaspirillum (96.3-97.0%) and Collimonas (96.2-97.0%). Although phylogenetically closely related to the type strain of G. immobilis, the low level of DNA-DNA hybridization between the two strains (21.6%) and several physiological and biochemical properties indicated that the novel strain could be clearly distinguished from G. immobilis LMG 25547(T). Therefore, it is concluded that strain A2-57(T) represents a novel species of the genus Glaciimonas, for which the name Glaciimonas singularis sp. nov. is proposed. The type strain is A2-57(T) (=CIP 110539(T)=LMG 27070(T)).