Co-Existence of Oxazolidinone Resistance Genes <i>cfr</i>(D) and <i>optrA</i> on Two <i>Streptococcus parasuis</i> Isolates from Swine
Ning Han,
Jie Li,
Peng Wan,
Yu Pan,
Tiantian Xu,
Wenguang Xiong,
Zhenling Zeng
Affiliations
Ning Han
Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
Jie Li
Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
Peng Wan
Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
Yu Pan
Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
Tiantian Xu
Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
Wenguang Xiong
Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
Zhenling Zeng
Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
This study was performed to investigate the presence and characteristics of the oxazolidinone resistance genes optrA and cfr(D) in Streptococcus parasuis. In total, 36 Streptococcus isolates (30 Streptococcus suis isolates, 6 Streptococcus parasuis isolates) were collected from pig farms in China in 2020–2021, using PCR to determine the presence of optrA and cfr. Then, 2 of the 36 Streptococcus isolates were further processed as follows. Whole-genome sequencing and de novo assembly were employed to analyze the genetic environment of the optrA and cfr(D) genes. Conjugation and inverse PCR were employed to verify the transferability of optrA and cfr(D). The optrA and cfr(D) genes were identified in two S. parasuis strains named SS17 and SS20, respectively. The optrA of the two isolates was located on chromosomes invariably associated with the araC gene and Tn554, which carry the resistance genes erm(A) and ant(9). The two plasmids that carry cfr(D), pSS17 (7550 bp) and pSS20-1 (7550 bp) have 100% nucleotide sequence identity. The cfr(D) was flanked by GMP synthase and IS1202. The findings of this study extend the current knowledge of the genetic background of optrA and cfr(D) and indicate that Tn554 and IS1202 may play an important role in the transmission of optrA and cfr(D), respectively.
