Emergence of Linezolid Resistance Genes <i>optrA</i> and <i>cfr</i>(D) in an <i>Enterococcus saccharolyticus</i> from Chicken

<b>Background:</b> The emergence of linezolid resistance, mediated by genes such as <i>optrA</i> and <i>cfr</i>(D), poses a growing public health threat. While these genes have been detected in clinical and animal-derived <i>Enterococcus</i> species, t...

Full description

Saved in:
Bibliographic Details
Main Authors: Xun Gao, Xiao Luo, Ruorou Qian, Guolong Gao, Jinghao Liu, Junhao Hong, Chao Yue, Jian-Hua Liu, Yi-Yun Liu
Format: Article
Language:English
Published: MDPI AG 2025-03-01
Series:Antibiotics
Subjects:
Online Access:https://www.mdpi.com/2079-6382/14/4/337
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:<b>Background:</b> The emergence of linezolid resistance, mediated by genes such as <i>optrA</i> and <i>cfr</i>(D), poses a growing public health threat. While these genes have been detected in clinical and animal-derived <i>Enterococcus</i> species, their presence in underexplored species like <i>Enterococcus saccharolyticus</i> remains undocumented, leaving a significant gap in our understanding of their dissemination and stability. <b>Method</b>: <i>E. saccharolyticus</i> GXN23C125Es was screened for the presence of known linezolid resistance genes via PCR analysis. Conjugation and stability experiments were used to evaluate the transferability and stability of the resistance genes. The complete genome of GXN23C125Es was obtained using both the Illumina and Nanopore platforms. <b>Results</b>: We report the first identification of <i>optrA</i> and <i>cfr</i>(D) in GXN23C125Es from chicken feces in China. Whole-genome sequencing revealed multiple plasmid-borne resistance genes, including <i>optrA</i>, <i>cfr</i>(D), <i>fexA,</i> and <i>erm</i>(A). Stability testing demonstrated that <i>optrA</i> was highly stable, while <i>cfr</i>(D) was rapidly lost without selective pressure. <b>Conclusions</b>: These findings highlight <i>E. saccharolyticus</i> as a potential reservoir for linezolid resistance genes, underscoring the need for enhanced surveillance of resistance determinants in animal-associated bacteria. Understanding the dissemination dynamics of <i>optrA</i> and <i>cfr</i>(D) is crucial for mitigating their impact on public health and guiding antimicrobial resistance management strategies.
ISSN:2079-6382