中国兽医科学2017，Vol.47Issue(4)：514-522,9.DOI:10.16656/j.issn.1673-4696.2017.04.018
食品动物源沙门菌fosA3基因的流行及传播特征
Prevalence and dissemination of fosfomycin resistance gene rosA3 among Salmonella isolates from food-producing animals
摘要
Abstract
To investigate the prevalence and dissemination of plasmid-mediated fosfomycin resistance gene related to fosA3 among Salmonella isolates from food-producing animals in China,a total of 288 Salmonella isolates stored in our laboratory were used in this study.The presence fosfomycin resistance genes such as fosA3,fosA,and fosC2 and other associated resistance genes were screened by PCR.The susceptibility of fos-positive isolates to 17 kinds antimicrobial agents was performed by the ager dilution method,and serotypes were confirmed by slide agglutination.Pulsedfield gel electrophoresis(PFGE) and multi-locus sequence typing(MLST) were used to analyze the genetic relationship among strains.Plasmid analysis was carried out by conjugation,transformation,plasmid replicon type,S1-PFGE and Southern-blot.Six(2.1％) Salmonella isolates were positive for fosA3.None of the fosA or fosC2 was identified.All of these isolates were S.enterica serovar Indiana and presented multi-drug resistant phenotypes.Both blaCTX-M-9Gand floR genes were detected in the fosA3 positive strains.MLST and PFGE results showed that all the 6fosA3-harbouring Salmonella isolates belonged to MLST(ST) 17 and were clonally related.The result of plasmid analysis showed that fosA3 could be cotransferred with the blaCTX-M gene through IncN or IncA/C plasmids.The current study is the first report of the detection of fosA3 in Salmonella isolates from fecal swab samples among chickens in China.Both clonal spread of resistant strains and horizontal transmission of the resistance plasmids contributed to the dissemination of fosA3/blaCTX-M-9G-positive Salmonella isolates.It may pose a potential threat to public health.关键词
沙门菌/fosA3/blaCTX-MKey words
Salmonella/fosA3/blaCTX-M分类
农业科技引用本文复制引用
谷茜茜,张文慧,张莉娟,杨玲,傅嘉莉,蒋红霞..食品动物源沙门菌fosA3基因的流行及传播特征[J].中国兽医科学,2017,47(4):514-522,9.基金项目
国家自然科学基金项目(31272602) （31272602）
