Microvirga terrae sp. nov., Isolated from Soil

Abstract

A Gram-stain-negative and strictly aerobic bacterium, strain R24^T, was isolated from soil in South Korea. Cells were non-motile short rods showing catalase- and oxidase-positive activities. Growth was observed at 15-40 °C (optimum, 25-30 °C) and pH 6.0-10.0 (optimum, 8.0-9.0), and in the presence of 0-3.0% NaCl (optimum, 0%). Strain R24^T contained ubiquinone-10 as the sole respiratory quinone, C_16:0, C_18:0, and summed feature 8 (comprising C_18:1 ω7c and/or C_18:1 ω6c) as the major fatty acids, and phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, and phosphatidylcholine as the major polar lipids. The DNA G+C content calculated from the whole genome sequence was 64.4%. Strain R24^T was most closely related to Microvirga aerilata 5420S-16^T with a 98.6% 16S rRNA gene sequence similarity. Average nucleotide identity and digital DNA-DNA hybridization values between strain R24^T and all Microvirga species were less than 82.5 and 23.8%, respectively. Phylogenetic analyses based on the 16S rRNA gene and whole genome sequences revealed that strain R24^T formed a phyletic lineage within the genus Microvirga. Based on its phenotypic, chemotaxonomic, and molecular characteristics, strain R24^T represents a novel species of the genus Microvirga, for which the name Microvirga terrae sp. nov. is proposed. The type strain is R24^T (= KACC 21784^T = JCM 34259^T).