摘要
规律成簇间隔短回文重复序列(clustered regularly interspaced short palindromic repeats,CRISPR)是大多数细菌和古细菌在生存压力下进化出的一套抵抗噬菌体干扰的防御系统。本研究主要采用生物信息学的方法,对24株分离自人体且已完成全基因组测序的副溶血性弧菌内CRISPR结构进行了分析,结果发现:只有16株细菌包含1个及以上的CRISPR结构,共计29个CRISPR;仅11个具有真座位特征的CRISPR结构含有前导序列;CRISPR结构中的重复序列所形成的RNA二级结构具有一大一小共两环或一大二小共三环的特征;目前未找到与区间序列高度同源的外源遗传物质;仅含前导序列的CRISPR结构侧翼区才存在cas基因。副溶血性弧菌的CRISPR结构可能以水平基因转移的方式整合到细菌的染色体中,CRISPR结构不适合作为细菌分类的一项指标。
Clustered regularly interspaced short palindromic repeats(CRISPR), evolved under the pressure of survival in many bacteria and archaea, are sets of defending system against phage interference. In this study, the CRISPR structure was analyzed in 24 Vibro parahaemolyticus strains with whole genome sequences based on some bioinformatic methods. Only 16 strains contain one or more CRISPR structures, and finally 29 CRISPRs were identified with this structure. Moreover, 11 CRISPRs with real loci structure contain leader sequences among them.RNA secondary structure formed by repeat sequences of CRISPR has a feature with two rings of one large and one small, or with three rings of one large and two small. Whereas, no exogenous sequence was found that was high homologous with a spacer sequence of CRISPR. Genes of cas only distribute in the CRISPR flanking region with a leader sequence. A CRISPR structure may be integrated into the V. parahaemolyticus chromosome by horizontal gene transfer, so it is not suitable as an indicator of bacterial classification.
出处
《基因组学与应用生物学》
CAS
CSCD
北大核心
2015年第8期1712-1722,共11页
Genomics and Applied Biology
基金
国家自然科学基金(No.31301566)
高等学校博士学科点专项科研基金(No.20133326120008)
国家国际科技合作专项(2013DFG32390)
食品科学与工程浙江省重中之重一级学科(No.JYTSP20142071)
浙江省公益性技术应用研究计划项目(分析测试)(No.2015C37067)共同资助
