Nocardioides pymetrozini sp. nov., a pymetrozine-degrading bacterium isolated from long-term continuous cropping...

A novel bacterial strain, designated as R1-1^T, was isolated from the saline-alkaline soil of a cotton field in Xinjiang, China. Strain R1-1^T grew at 20-45 ℃, pH 4.0-11.0 and 0-10% NaCl. Notably, this strain degraded 50 mg l^-1 pymetrozine within 18 h at pH 8.0. Phylogenetic analysis based on the 16S rRNA gene sequence indicated that strain R1-1^T belongs to the genus Nocardioides, showing a high sequence similarity to 'Nocardioides carbamazepini' CBZ-1^T (98.5%). Other closely related species included Nocardioides albidus THG-S11.7^T (98.0%), Nocardioides convexus W3-2-3^T (98.0%), Nocardioides kongjuensis A2-4^T (98.0%) and Nocardioides daeguensis JCM 17460^T (97.4%). The genome sequence of strain R1-1^T had a G+C content of 72.2 mol%. The average nucleotide identity and DNA-DNA hybridization values between strain R1-1^T and its closest phylogenetic relatives were 84.5-84.9% and 28.5-28.7%, respectively. These values were below the determined thresholds for species delineation. The major fatty acids of strain R1-1^T were identified as 10-methyl C_18 : 0, iso-C_16 : 0 and C_18 : 1 ω9c. The predominant respiratory quinone was menaquinone-8 (H₄), and the polar lipid profile comprised diphosphatidylglycerol, phosphatidylglycerol, two unidentified phospholipids and two unidentified lipids. Based on the polyphasic taxonomic data, strain R1-1^T represents a novel species within the genus Nocardioides, for which the name Nocardioides pymetrozini sp. nov. is proposed. The type strain is R1-1^T (=KCTC 59241^T=GDMCC 4.365^T).