Azohydromonas riparia sp. nov. and Azohydromonas ureilytica sp. nov. isolated from a riverside soil in South Korea.

Abstract

White and pale yellow coloured bacteria were isolated from the riverside soil, Daejeon, South Korea, and were designated UCM-11(T), UCM-F25, and UCM-80(T). We found that all strains were able to reduce nitrate, and the cells were aerobic and motile. The DNA G+C contents of UCM-11(T), UCM-F25, and UCM-80(T) were between 68.9 to 71.2 mol% and the main ubiquinone was observed as Q-8. Based on16S rRNA gene sequences, strains UCM-11(T) and UCM-F25 were found to closely match with Azohydromonas australica IAM 12664(T) (98.48-98.55%), and the strain UCM-80(T) was the closest match with Azohydromonas lata IAM 12599(T) (98.34%). The presence of summed feature 3 (C16:1 ω7c and/or C16:1 ω6c), C16:0, summed feature 8 (C18:1 ω7c and/or C18:1 ω6c) as well as twokinds of hydroxyfatty acids consisting of C10:0 3-OH and C12:0 2-OH, and branched fatty acids containing C16:0 iso and C17:0 cyclo were detected in all the strains. Phosphatidylethanolamine was a major polar lipid. DNA-DNA relatedness confirmed UCM-11(T), UCM-F25 and UCM-80(T) as novel members of the genus Azohydromonas. Based on the morphological, physiological, biochemical and genotypic characteristics, we suggest that strains UCM-11(T), UCM-F25, and UCM-80(T) represent novel species within the genus Azohydromonas. The names Azohydromonas riparia sp. nov., and Azohydromonas ureilytica sp. nov. are proposed for the type strains UCM-11(T) (=KACC 18570(T) =NBRC 111646(T)) and UCM-80(T) (=KACC 18576(T) =NBRC 111658(T)), respectively.