摘要
为研究观赏禽类中分离的奇异变形杆菌(Proteus mirabilis)对第三代头孢菌素的耐药机制,于2019年从河南省某动物园禽类养殖区绿孔雀(Pavo muticus)、红绿金刚鹦鹉(Ara chloroptera)、火鸡(Meleagris gallopavo)、帽子鸡(polish chicken)和非洲鸵鸟(Struthio camelus)5种观赏禽类中分离17株奇异变形杆菌,经药物敏感性试验、blaCTX-M基因检测、全基因组测序、PFGE和RT-qPCR等探明受试菌对第三代头孢菌素的耐药机制。结果发现:共有6株受试菌对第三代头孢菌素耐药,除1株(6D)携带超广谱β-内酰胺酶blaCTX-M-14和1株(106A)携带AmpC酶blaACT-16外,其余4株经PFGE检测证实为同一克隆型,且细菌体内双组分信号转导系统CpxAR、BaeSR和EnvZ/OmpR的表达量显著高于敏感菌,主要通过抑制耐药菌细胞膜上OmpC和OmpF的表达减少药物吸收,同时促进OmpW表达加速药物外排,从而减少菌体内药物浓度,进而导致其对第三代头孢菌素类耐药。研究表明,动物园禽类养殖区的奇异变形杆菌对第三代头孢菌素的耐药机制复杂多样,散播机制主要为染色体介导的克隆传播,应引起重视。
To study the molecular mechanism of resistance to third-generation cephalosporins in Proteus mirabilis.In 2019,17 strains of Proteus mirabilis were isolated from the five ornamental birds such as green peacock(Pavo muticus),red-and-green macaw(Ara chloroptera),turkey(Meleagris gallopavo),polish chicken,and African ostrich(Struthio cam⁃elus)in the poultry breeding area of a zoo in Henan Province.The mechanism of resistance of Proteus mirabilis to thirdgeneration cephalosporins was explored by antimicrobial susceptibility test,blaCTX-M gene detection,whole genome se⁃quencing,pulsed field gel electrophoresis and real-time relative quantitative PCR.The results showed that a total of six strains were resistant to third-generation cephalosporins,except for 6D carrying the extended-spectrumβ-lactamase blaCTX-M-14 and 106A carrying the AmpC enzyme blaACT-16,the other four strains were confirmed to be the same clone by pulsed field gel electrophoresis detection.and the expression levels of CpxAR,BaeSR and EnvZ/OmpR in the twocomponent signal transduction system in drug-resistant bacteria were significantly higher than those in the sensitive bacte⁃ria,and it reduces drug absorption by regulating the expression of OmpC and OmpF in the cell membrane of drug-resistant bacteria;Promote the expression of OmpW and accelerate drug efflux,thereby reducing the drug concentration in the antimicrobial-resistant bacteria,which in turn leads to their resistance to third-generation cephalosporins.These results indi⁃cate that the resistance mechanism of Proteus mirabilis to third-generation cephalosporins isolated in the poultry breeding area of the zoo is complex and diverse,and the dispersal mechanism is mainly chromosome-mediated clonal transmission,which should be paid attention to.
作者
梁玉蕾
李垠树
陈秋如
董焱斌
丁爱萍
苑丽
LIANG Yulei;LI Yinshu;CHEN Qiuru;DONG Yanbin;DING Aiping;YUAN Li(College of Veterinary Medicine,Henan Agricultural University,Zhengzhou,450002,China;Zhengzhou Zoo,Zhengzhou,450008,China)
出处
《野生动物学报》
北大核心
2024年第4期811-818,共8页
CHINESE JOURNAL OF WILDLIFE
基金
河南省高校科技创新团队支持计划项目(23IRTSTHN021)
河南省自然科学基金重点项目(232300421111)。
关键词
禽源奇异变形杆菌
头孢菌素类
耐药基因
膜孔蛋白
双组分信号转导系统
Avian-origin Proteus mirabi⁃lis
Cephalosporins
Resistance gene
Porins
Two-component signal trans‐duction system
