青藏铁路沿线鼠疫菌表型性状及对抗生素敏感性的研究

目的检测青藏铁路沿线鼠疫菌表型性状、质粒组成、外膜蛋白种类及对抗生素的敏感性。方法采用常规糖醇发酵管法检测生化等表型性状；采用反向血凝试验、用假结核菌为复盖种子层法、用草酸镁培养基和刚果红色素培养基检测FraI、Pstl、Vwa和Pgm4种毒力因子；用Lawton最小培养基测定营养型；采用常规的动物接种试验测定毒力；采用碱裂解、酚一氯仿抽提法提取鼠疫菌质粒；鼠疫菌经破碎后采取超高速离心法提取外膜蛋白；采用纸片法进行抗生素敏感性试验。结果实验用的青藏铁路沿线鼠疫菌株生化性状表现为甘油＋、鼠李糖一、阿胶糖＋、密二糖一、麦芽糖＋、脱氮＋的特征；具有鼠疫菌荚膜抗原（FraI＋）、毒力抗原（Vwa＋）、鼠疫菌素I（PstI＋）、色素沉着因子（Pgm＋）4种毒力因子；营养型表现为对Trp、Thr、Leu、Arg不依赖，而对Phe、Met、Cys依赖，对Ile和Glu表现出低营养；对小白鼠的LD100在10^2～10^3个菌，LDs。为7．94-31．62个菌，对豚鼠的LD100在10^5～10^7个菌，LD50为68．14-685．49个菌；携带Mr为6×10^6、45×10^6、52×10^6、65×10^6、92×10^6]质粒；在10％的SDS-PAGE上37℃条件下的培养物可表达26条外膜蛋白带，28℃培养物可表达36条外膜蛋白；部分头孢类和喹诺酮类药物对实验菌株的敏感性效果较好，20种抗生素均较链霉素为佳。结论青藏铁路沿线的鼠疫菌属于典型的青藏高原型菌株，都是强毒力鼠疫菌，临床治疗除常规的链霉素外可选用头孢类和喹诺酮类药物，该项研究可为青藏铁路沿线的鼠疫防治提供科学的依据。

The phenotype character and antibiotic sensitivity of Yersinia pestis along Qinghai-Tibet Railway

Objective To study and detect the character and plasmid and outer membrane proteins and antibi- otic sensitivity of the Yersinia pestis along the Qinghai-Tibet Railway. Methods Some phenotype characters of sug- ar-alcohol fermentation was adopted. RIHA, seed layer method by the Yersinia pseudotuberculosis,magnesium ox- alate medium and congo red medium were adopted to detect FraI, Pstl, Vwa and Pgm; Lawton medium was adopted to detect nutritional type;animal inoculation test was adopted to detect virulence; alkaline lysis, Phenol-chloroform extraction was adopted to distill the plasmid of the Y. pestis; ultracentrifuge was adopted to extract outer membrane proteins of Yersinia pestis ; scrip method was adopted to test the antibiotic susceptibility. Results The Y. pestis bi- ochemistry character included glycerol ＋, rhamnose --, melibiose --, maltose ＋, denitrification ＋ ; there were FraI ＋, Vwa ＋, Pst I ＋, Pgm in animal experiment the white mouse LD100 ： 10^2-10^3, LD50 ： 7.94~31.62, the cavy LD100 ： 10^5 -10^7, LDs0 ： 68.14-685.49; the Yersinia pestis along Qinghai--Tibet Railway depended on Phe, Met, Cys, not on Trp, Thr, Leu, Arg; the tests showed meiotroph of Ile and Glu, and contained the plasmid of 6 ×10^6 、45×10^6、 52×10^6、65×10^6、 92 ×10^6Mr; therewere 26 stripes of outer membrane proteins at 37℃ and 36 stripes at 28℃ in 10% SDS-PAGE eleetrophoresis; the Yersinia pestis was sensitive to some of cephalosporin and carbostyril, and 20 antibiotics were better than streptomycin. Conclusion the Yersinia pestis along Qinghai-Tibet Railway is standard strain of Qinghai-Tibet plateau ecotype. The research might provide scientific evidence for pre- vention and control of plague along the Qinghai-Tibet Railways.