青霉素压力下金黄色葡萄球菌对β-内酰胺类抗生素的耐药表型变化  

Resistant phenotype of staphylococcus aureus on beta-lactam antibiotics under penicillin pressure

作　　者：尹金花[1] 高健[1] 陈学礼 刘永夏[1] 韩博[1] 

机构地区：[1]中国农业大学动物医学院,北京海淀100193 [2]云南省迪庆州高原生物研究所,云南香格里拉674499

出　　处：《中国兽医杂志》2014年第11期3-6,共4页Chinese Journal of Veterinary Medicine

基　　金："十二五"国家科技支撑计划"奶牛健康养殖重要疾病防控关键技术研究项目(2012BAD12B03-1-6);教育部重大项目"奶牛乳房炎重要病原菌新型缓释微球疫苗的研制"(313054)

摘　　要：为了阐明奶牛乳房炎源性金黄色葡萄球菌在青霉素压力作用下的表型变化,本试验对1株mec A基因缺失的金黄色葡萄球菌在体外进行亚抑菌浓度的青霉素诱导,利用K-B纸片法和电镜技术观察不同诱导代次金黄色葡萄球菌的表型特征,并用菌落计数法分析耐药亚群生长曲线。试验结果显示,随着诱导代次的增加,金黄色葡萄球菌对β-内酰胺类抗菌药物即青霉素和苯唑西林的耐药性逐渐增强,对各浓度β-内酰胺类抗菌药物的耐药亚群比例升高;表型观察发现金黄色葡萄球菌诱导菌菌体变小,胞质浓缩,细胞壁疏松和增厚,有的胞浆内出现空泡。研究表明,金黄色葡萄球菌在亚抑菌浓度青霉素的体外作用下,发生了表型和生长曲线的适应性改变。这为金黄色葡萄球菌耐药机制的研究奠定了基础,并为临床上奶牛乳房炎的防治提供了依据。Staphylococcus aureus（S.aureus）is one of the most commonly-seen pathogens responsible for contagious bovine mastitis.The organisms can tolerate a wide range of adverse circumstances.However,few reports concerned resistant phenotype of S.aureus. The present study was designed with an objective to elucidate the resistant phenotype of S.aureus on beta-lactam antibiotics under penicillin pressure. Penicillin was used to induce a S.aureus strain without mec A gene in vitro,the changes on phenotype were observed,and the growth curve of resistance subpopulation was analyzed.The results showed that resistance against beta-lactams increased gradually with induction,the proportion of resistance subpopulation against penicillin became higher,and the bacterial body became smaller,cytoplasm more concentrated,cell walls were more thicker,even some vacuoles appeared in the cytoplasm. Therefore,the data concluded that the phenotype and growth curve of resistance subpopulation of S.aureus on beta-lactam antibiotics under penicillin pressure changed.The study explored the basis of resistance on S.aureus and provided evidences for prevention and treatment of dairy mastitis.

关 键 词：青霉素压力 金黄色葡萄球菌 Β-内酰胺类抗菌药物 耐药表型 

分 类 号：S852.61[农业科学—基础兽医学]