Cupriavidus lacunae sp. nov., isolated from pond-side soil

A Gram-stain negative, strictly aerobic, mesophilic bacterial strain, designated strain S23^T, was isolated from pond-side soil of an artificial pond in South Korea. Cells were observed to be peritrichously flagellated short rods showing positive oxidase and catalase activities. Growth of strain S23^T was observed at 15-37 °C (optimum, 30 °C), pH 5.0-9.0 (optimum, pH 7.0-8.0) and 0-2% (w/v) NaCl (optimum, 0-0.5%). The major respiratory quinone was identified as ubiquinone-8 and the major fatty acids were identified as C_16:0, cyclo-C_17:0, summed feature 3 (C_16:1ω7c and/or C_16:1ω6c) and summed feature 8 (C_18:1ω7c and/or C_18:1ω6c). The G + C content of the genomic DNA was determined to be 65.1 mol%. Phosphatidylglycerol, phosphatidylethanolamine and an unidentified phospholipid were detected as the major polar lipids. Phylogenetic analyses based on 16S rRNA gene sequences showed that strain S23^T formed a phyletic lineage with Cupriavidus necator N-1^T within the genus Cupriavidus. Strain S23^T is closely related to C. necator N-1^T (99.2%), Cupriavidus basilensis DSM 11853^T (98.8%), Cupriavidus alkaliphilus ASC-732^T (98.8%) and Cupriavidus numazuensis TE26^T (98.7%), based on 16S rRNA gene sequence similarities. However, the DNA-DNA relatedness values between strain S23^T and the closely related type strains were less than 46%. On the basis of phenotypic, chemotaxonomic and molecular properties, strain S23^T represents a novel species of the genus Cupriavidus, for which the name Cupriavidus lacunae sp. nov. is proposed. The type strain is S23^T (KACC 19624^T = JCM 32674^T).