Acidovorax lacteus sp. nov., isolated from a culture of a bloom-forming cyanobacterium (Microcystis sp.)

Abstract

A novel Gram-negative, rod-shaped and motile bacterial strain, designated strain M36^T, was isolated from a culture of a bloom-forming cyanobacterium, Microcystis sp., collected from a eutrophic lake in Korea. Its taxonomic position was investigated by using a polyphasic taxonomic approach. The isolate was found to grow aerobically at 15-42 °C (optimum 25 °C), pH 7.0-11.0 (optimum pH 8.0) and in the presence of 0-1.0% (w/v) NaCl (optimum 0% NaCl) on R2A medium. The phylogenetic analysis based on 16S rRNA gene sequences revealed that the strain M36^T is closely related to Acidovorax anthurii DSM 16745^T (98.1%), Acidovorax konjaci DSM 7481^T (97.7%) and Acidovorax avenae DSM 7227^T (97.0%) and also formed a clear phylogenetic lineage with other Acidovorax species. DNA-DNA relatedness between strain M36^T and the closely related species of the genus Acidovorax was <30%. The major fatty acid components identified included summed feature 3 (C_16:1 ω7c and/or C_16:1 ω6c), C_16:0 and summed feature 8 (C_18:0 ω7c and/or C_18:0 ω6c). The DNA G+C content of strain M36^T was determined to be 66.8 mol%. Based on above polyphasic evidence, strain M36^T is concluded to represent a new species of genus Acidovorax, for which the name Acidovorax lacteus sp. nov. is proposed. The type strain is M36^T (=KCTC 52220^T = JCM 31890^T).

Keywords: Acidovorax; Acidovorax lacteus sp. nov.; Microcystis; Polyphasic taxonomy.