Pseudomonas oryzae sp. nov. isolated from a paddy soil in South China

摘要

A Gram-staining-negative, rod-shaped and motile with several polar flagellums bacterium, designated WM-3T, was isolated from a rice paddy soil in South China. Growth occurred with 0–3.0 % (w/v) NaCl (optimum 2.0 %), at pH 5.5–9.0 (optimum pH 7.0) and at 25–42 °C (optimum 30–37 °C) in liquid Reasoner’s 2A medium. Analysis of the 16S rRNA gene and gyrB gene sequences revealed that strain WM-3T was most closely related to the type strains of the species Pseudomonas linyingensis and Pseudomonas sagittaria. Its sequence similarities with P. linyingensis CGMCC 1.10701T and P. sagittaria JCM 18195T were 97.4 and 97.3 %, respectively, for 16S rRNA gene, and were 94.1 and 94.2 %, respectively, for gyrB gene. DNA–DNA hybridization between strain WM-3T and these two type strains showed relatedness of 35.6 and 30.9 %, respectively. G+C content of genomic DNA was 69.4 mol%. The whole-cell fatty acids mainly consisted of C16:0 (30.0 %), C16:1 ω6c and/or C16:1 ω7c (19.3 %) and C18:1 ω6c and/or C18:1 ω7c (16.3 %). The results of phenotypic, chemotaxonomic and genotypic analyses clearly indicated that strain WM-3T belongs to genus Pseudomonas but represents a novel species, for which the name Pseudomonas oryzae sp. nov. is proposed. The type strain is WM-3T (=KCTC 32247T =CGMCC 1.12417T).