多耐药金黄色葡萄球菌感染已成为世界范围内重要的公共卫生问题。细菌在进化过程中，通过质粒、转座子等可移动遗传元件获得耐药基因以适应环境而生长。CRISPR系统是最近发现的细菌针对噬菌体、质粒等外源基因的获得性免疫系统，其间隔序列记录了外来入侵遗传元件的信息，在一定程度上反映了细菌的进化方向。本课题从河南某省级综合医院分离金葡菌，一方面对金葡菌CRISPR位点进行检测及结构生物信息分析，描述CRISPR系统在我国分离金葡菌中的分布规律及结构特征。并对其与金葡菌耐药性和耐药基因分布进行研究，分析CRISPR系统间隔序列组成对细菌多耐药影响；另一方面对MRSA SCCmec（耐药岛）基因分型，分析CRISPR结构多态性与MRSA SCCmec基因特征的关系，初步探索基于CRISPR系统的MRSA在不同环境下的进化历程。为进一步揭示金葡菌耐药发生规律、预测多耐药株的发展趋势及预防其暴发提供科学依据。

It has been an important public health problem for human being to infect multi-drug resistant Staphylococeus aureus(S. aureus). The bacteria happen evolution through acquiring resistance gene from plasmid and phage or other mobile genetic elements. Clustered regularly interspaced short palindromic repeats (CRSIPR） are recently discovered and provide acquired immunity against foreign DNA. The spacers record the information of the mobile genetic elements, which invaded the bacteria, and reflect the evolutionary of bacteria. In our study, S. aureus will be isolated from a hospital of Henan province. First, we study CRISPR in S. aureus by bioinformatics analysis, and describe the distribution and structural characteristics of S. aureus. Furthermore, we study the relation between CRISPR spacers and the resistance and resistance genes with S. aureus. Second, MRSA will be genotyping with SSCmec, and the relation between the polymorphism of CRISPR and MRSA SSCmec typing will be analyzed, which makes it possible to be used as evolution study. This study helps reveal the occurrence of resistance, predict the development trend of multi-resistant strains and prevent theirs outbreak.