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 (C_16:1 ω7c and/or C_16:1 ω6c), C_16:0, summed feature 8 (C_18:1 ω7c and/or C_18:1 ω6c) as well as twokinds of hydroxyfatty acids consisting of C_10:0 3-OH and C_12:0 2-OH, and branched fatty acids containing C_16:0 iso and C_17:0 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.