猪链球菌SC124菌株中ICE_Prophage携带耐药基因的水平转移  

Horizontal Transfer of Drug Resistance Genes Carried by ICE_Prophage in Streptococcus suis SC124

作　　者：段慧慧 任仕航 张宏印 于瑞 刘忠虎[1] 杜向党[1] 商艳红[1] DUAN Huihui;REN Shihang;ZHANG Hongyin;YU Rui;LIU Zhonghu;DU Xiangdang;SHANG Yanhong(College of Veterinary Medicine,Henan Agricultural University,Zhengzhou,Henan 450046,China;College of Veterinary Medicine,Henan University of Animal Husbandry and Econom,Zhengzhou,Henan 450046,China)

机构地区：[1]河南农业大学动物医学院,河南郑州450046 [2]河南牧业经济学院动物医药学院,河南郑州450046

出　　处：《畜牧兽医学报》2024年第8期3699-3705,共7页ACTA VETERINARIA ET ZOOTECHNICA SINICA

基　　金：河南省重点研发与推广专项(科技攻关)(232102110094,232102110110,242102110068)。

摘　　要：旨在探究猪链球菌中ICE_Prophage携带耐药基因转移的情况,使用Illumina MiSeq和Pacbio RSII平台对猪链球菌SC124菌株进行了全基因组测序,利用在线网站RAST、ICEberg 3.0、PHASTER和NCBI数据库对SC124菌株的基因组序列进行分析;用肉汤稀释法测定最小抑菌浓度;通过接合试验验证ICE_Prophage携带耐药基因的可转移性;采用反向PCR检测环状中间体的存在;用竞争试验评估接合子是否具有适应性代价。结果显示:猪链球菌SC124菌株中存在携带四环素类、大环内酯类和氨基糖苷类耐药基因的ICE_Prophage(ICE Ssu SC124_ΦSsuSC124);携带四环素类耐药基因的ICE Ssu SC124以5.52×10-9频率发生转移,未发现前噬菌体发生转移;ICE Ssu SC124可以形成一个大小约为3.8 kb的环状中间体;与猪链球菌BAA相比,含有ICE Ssu SC124的接合子在无药物压力选择的作用下不具有竞争优势,接合子会产生一定程度的适应性代价。综上,猪链球菌SC124菌株中存在携带四环素类、大环内酯类和氨基糖苷类耐药基因的ICE_Prophage,ICE Ssu SC124可发生水平转移,其接合子可产生一定程度的适应性代价。This study aimed to investigate the transfer of drug antibiotic resistance genes(ARGs)carried by ICE_Prophage in Streptococcus suis.The whole genome sequencing of S.suis SC124 was sequenced by performed using the Illumina MiSeq and Pacbio RSII platforms.The whole genome sequence of SC124 strain isolates was analyzed by online websites RAST,ICEberg 3.0,PHASTER and NCBI database.MICs were determined by broth microdilution.The transferability of ICE_Prophage carrying drug resistance genes ARGs in S.suis was investigated by conjugation.The present of circular intermediates was examined by inverse PCR.Competition was used to evaluate whether the transconjugant had fitness cost.The results showed that there was an ICE_Prophage(ICE Ssu SC124_ΦSsuSC124)carrying tetracycline,macrolide and aminoglycoside resistance genes in S.suis SC124 strain.ICE Ssu SC124 carrying tetracycline resistance genes was transferred at a frequency of 5.52×10-9,and no prophage transfer was found.Inverse PCR revealed that ICE Ssu SC124 formed a circular intermediate with a size of about 3.8 kb.Compared with S.suis BAA,the transconjugant containing ICE Ssu SC124 did not have a competitive advantage under the action of drug-free pressure selection,and the transconjugant can produce a certain degree of fitness cost.These results indicated that In conclusion,the ICE_Prophage carrying tetracycline,macrolide and aminoglycoside resistance genes in S.suis SC124,in which ICE Ssu SC124 could be horizontally transferred,and the transconjugant could produce a certain degree of fitness cost.

关 键 词：猪链球菌 ICE_Prophage 接合试验 适应性代价 

分 类 号：S852.611[农业科学—基础兽医学]