Wu Chang-Song, Lin Jian-Hao, Chen Ming, Huang Yan, Zhang Yong-An
National Key Laboratory of Agricultural Microbiology, Hubei Hongshan Laboratory, Engineering Research Center of Green Development for Conventional Aquatic Biological Industry in the Yangtze River Economic Belt, Ministry of Education, College of Fisheries, Huazhong Agricultural University, Wuhan, PR China.
Guangxi Zhuang Autonomous Region Center for Disease Control and Prevention, Nanning, PR China.
Microb Genom. 2025 Sep;11(9). doi: 10.1099/mgen.0.001482.
Lincosamides serve as alternative therapeutic agents for penicillin-allergic patients with [group B (GBS)] infections, but the escalating antibiotic resistance has severely compromised their clinical efficacy. This study investigated the epidemiological characteristics of antibiotic resistance and the co-transfer mechanisms of lincosamide resistance genes and in 631 clinical GBS isolates from southern China. The results showed that 98.3% of isolates carried at least one antibiotic resistance gene, with lincosamide resistance genes detected in 76.1% of isolates. The and were identified as prevalent lincosamide resistance determinants alongside , with 18.7% of isolates co-carrying and , and double-positive isolates predominantly distributed in high-risk clonal complexes (CCs): CC10 (15.4%), CC17 (21.7%), CC19 (17.9%) and CC103 (35.5%). Genomic analyses revealed that formed composite resistance modules by integrating into resistance gene clusters within integrative and conjugative elements (ICEs), with insertion sequence-mediated mobilization increasing their dissemination risk. In CC10 and CC17, ICE served as the primary ICE harbouring , while novel genetic contexts for were identified in CC19, CC23 and CC103. This study highlights the high prevalence of resistance clusters in GBS clinical isolates from southern China and their ICE-mediated dissemination mechanisms, providing critical molecular epidemiological evidence for resistance surveillance and precision therapeutic strategies.
林可酰胺类药物可作为青霉素过敏的B族链球菌（GBS）感染患者的替代治疗药物，但抗生素耐药性的不断升级严重影响了其临床疗效。本研究调查了来自中国南方的631株临床GBS分离株的抗生素耐药性流行病学特征以及林可酰胺耐药基因的共转移机制。结果显示，98.3%的分离株携带至少一种抗生素耐药基因，76.1%的分离株检测到林可酰胺耐药基因。除了erm(B)外，msr(A)和lnu(A)被鉴定为常见的林可酰胺耐药决定因素，18.7%的分离株同时携带erm(B)和lnu(A)，双阳性分离株主要分布在高危克隆复合体（CCs）中：CC10（15.4%）、CC17（21.7%）、CC19（17.9%）和CC103（35.5%）。基因组分析表明，erm(B)通过整合到整合性接合元件（ICEs）内的耐药基因簇中形成复合耐药模块，插入序列介导的移动增加了它们的传播风险。在CC10和CC17中，ICE是携带erm(B)的主要ICE，而在CC19、CC23和CC103中发现了erm(B)的新遗传背景。本研究突出了中国南方GBS临床分离株中erm(B)耐药簇的高流行率及其ICE介导的传播机制，为耐药监测和精准治疗策略提供了关键的分子流行病学证据。
