Aquamicrobium zhengzhouense sp. nov., a Bacterium Isolated from Farmland Soil Applied with Amino Acid Fertilizer

Abstract

A novel Gram-stain-negative, rod-shaped, strictly aerobic, non-motile bacterium, designated strain cd-1T, was isolated from a farmland soil applied with amino acid fertilizer in Zhengzhou, Henan province, China. The optimum growth of strain cd-1T occurred at 30°C, pH 7.0 in Luria-Bertani (LB) broth without NaCl supplement. Phylogenetic analysis based on 16S rRNA gene sequences indicated that cd-1T is member of the genus Aquamicrobium, and formed a separate branch with Aquamicrobium aerolatum DSM 21857T (96.5%) and Aquamicrobium soli KCTC 52165T (95.7%). The draft genome sequencing revealed a DNA G + C content of 59.2mol% and Q-10 was the predominant respiratory quinone. The major cellular fatty acids were identified as C18:1 ω7c (35.8%), C19:0 cyclo ω8c (32.1%), and C18:1 ω7c 11-methyl (5.2%). The polar lipids consisted of phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine and phosphatidylmonomethylethanolamine. Average nucleotide identity (ANI) and the digital DNA-DNA hybridizations (dDDH) for draft genomes between strain cd-1T and KCTC 52165T were 71.0% and 19.9%, respectively, the values for strain cd-1T and DSM 21857T were 73.4% and 20.6%. Based on the physiological and biochemical characteristics, phylogenetic and chemotaxonomic analysis, strain cd-1T is considered to represent a novel species of the genus Aquamicrobium, for which the name Aquamicrobium zhengzhouense sp. nov. is proposed. The type strain is cd-1T (= KCTC 82182T = CCTCC M 2018904T).