伤寒沙门菌耐药基因检测及定位

目的探讨伤寒沙门菌耐药基因的定位。方法３２Ｐ随机引物标记氯霉素耐药基因为探针，以Ｓｌｏｔｂｌｏｔ、Ｓｏｕｔｈｅｒｎｂｌｏｔ法检测，同时以氯霉素乙酰转移酶活性（ＣＡＴ）和药敏试验（ＭＩＣ）作为耐药标志。结果１６株伤寒菌中有１４株含９８６０００００大质粒。经杂交，其中７株质粒阳性；１株染色体阳性；３株质粒与染色体均为阳性。质粒杂交带位于４．３ｋｂ片段，染色体为５．２ｋｂ片段。结论伤寒菌耐氯霉素基因大部分位于９８６０００００大质粒上，少数位于染色体上或两者兼有

The detection and location of drug resistant gene in Salmonella typhi

Objective In order to probe the location of drug resistance gene of Salmonella typhi.Methods Detection was carried out by slot blot and southern blot,using Cm resistance gene labeled with~( 32) P by random primed method as the probe.CAT and MIC were exploited as the marker of drug resistance.Results In sixteen S.T strains,fourteen Strains had one 98 600 000 plasmid.Using hybridization method,we found out that 7 of the 14 strains plasmids were positive.While chromosome was positive for 1 strain.Both plasmid and chromosome were positive for 3 strains.The molecular weights of the hybridization positive fragments of plasmid and chromosome were 4.3kb and 5.2kb,respectively.Conclusion: The Cm resistance gene of S.T are mainly located on the 98 600 000 plasmid.However,some of them are located on chromosome or on both chromosome and plasmid.