单增李斯特菌hfq基因的克隆及分子特征分析  

Cloning and Molecular Characteristics of hfq Gene of Listeria monocytogenes

作　　者：彭叶龙[1] 乔军[1] 孟庆玲[1] 谢堃[1] 陈诚[1] 刘田莉 马玉[1] 才学鹏[2] 陈创夫[1] 

机构地区：[1]石河子大学动物科技学院动物疾病防控兵团重点实验室,新疆石河子832003 [2]中国农业科学院兰州兽医研究所,甘肃兰州730046

出　　处：《生物技术》2014年第4期1-4,共4页Biotechnology

基　　金：国家自然科学基金项目("ncRNA伴侣分子Hfq对单核细胞增生李斯特菌胞内寄生及致病力的调控作用及机制研究";No.31360596;"prfA基因突变对单核细胞增生性李氏杆菌毒力及免疫原性的影响";No.30960274);国家国际科技合作专项("预防绵羊支原体肺炎的重组活载体疫苗合作研究";No.2014DFR31310)资助

摘　　要：目的：了解单增李斯特菌（Listeriamonocytogenes，LM）SB5野毒株ncRNA伴侣分子怕基因及其编码蛋白质的分子生物学特征。方法：利用PCR方法对hfq基因进行扩增、克隆及测序，对魄向基因分子特征进行分析，预测其编码蛋白质的二三级结构及功能活性位点，对其进行同源性及遗传变异分析。结果：LMhfq基因全长234bp，编码77个氨基酸，对推导的Hfq氨基酸序列分析发现从N端到C端包含1个饯一螺旋及5个β-折叠，具有RNA结合位点及六聚体结合位点。LM-SB5hfq基因核苷酸序列与李斯特菌属各菌株同源率为94．5～100％，与其他种属细菌同源率为36．19—62．39％。结论：Hfq蛋白具有RNA的结合位点，可能在细菌ncRNA调节基因表达过程中发挥重要作用。Objective： In order to understand the biological characteristics of sRNA chaprone hfq gene of SB5 strain of Listeria monocyto- genes. Method：The hfq gene was amplified by PCR from LM- SB5 genome,then cloned into pMD18 -T vector, sequenced and ana- lyzed. The secondary and tertiary structure of the Hfq protein were predicted and analyzed. Homology and phylogenitic of hfq gene were an- alyzed among LM - SB5 and reference strains of Listeria together with other bacteria. Result： The results showed that the hfq gene had a length of 234 bp, encoding 77 amino acids. The Hfq protein had an N - terminal α - helix followed five - stranded antiparallel 13 - barrel. It had RNA binding sites and hexamer interfaces which is related to the RNA - binding and splicing process. Compared with the hfq gene nu- cleotide sequence of Listeria strains and other bacteria,the identities were 94. 5 ～100% and 36. 19 ～62. 39 % ,respectively. Conclusion： Hfq protein had RNA binding sites which may be involved in the regulation of bacterial ncRNA to the gene expression.

关 键 词：单增李斯特菌 危向基因 克隆 序列分析 

分 类 号：S852[农业科学—基础兽医学]