食源性单增李斯特菌LIPI-4基因的检测及序列分析

Detection and sequence analysis of LIPI-4 gene on food-borne Listeria monocytogenes

单核细胞增多性李斯特菌(Listeria monocytogenes,LM)作为四大重要食源性病原菌之一,对公共安全及畜牧业发展威胁极大。其毒力岛4(LIPI-4)是新发现的一个潜在毒力因子,与LM的神经感染和母胎感染密切相关。以54株食源性LM的DNA为模板,针对LIPI-4的6段基因设计特异性引物,利用PCR的方法检测LIPI-4的携带情况并对携带株的LIPI-4基因进行生物信息学分析。结果表明,54株LM中有5株携带LIPI-4基因,携带率为9.26%;5株食源性LM LIPI-4基因的同源性均为100%,与CC1代表株LM09-00558LIPI-4基因的同源性99%以上;对LIPI-4中EIIC结构域分析表明5株食源性LM LIPI-4均为PTSLac家族。食源性LM携带LIPI-4基因且属于PTSLac家族,研究LIPI-4基因对进一步了解LM的致病性具有重要意义。

Listeria monocytogenes(LM)is well known as one of the four important food-borne pathogens,poses a great threat to public safety and animal husbandry.Listeria pathogenicity island 4(LIPI-4)is a newly discovered potential virulence factor,which is closely related to LM nerve infection and placental infection.Specific primers were designed and synthesized for 6genes of LIPI-4,and these genes were detected by PCR from 54food-borne LM strains isolated from the different foods.The sequence of LIPI-4was analyzed by bioinformatics software.The results showed that 5 of 54strains of LM carried LIPI-4gene with a carrying rate of 9.26%;the homology of 5foodborne LM LIPI-4genes were 100%,and was more than 99%compared with that of LM09-00558 which was the representative strain of CC1.The analysis of EIIC domain in LIPI-4showed that the LIPI-4of five LM strains were all PTSLac family;sequence analysis of the the EIIC domain of LIPI-4gene indicated the LIPI-4of 5strains of LM were all PTSLac(EIIC)family.LIPI-4gene was detected from food-borne LM of Xinjiang and was belong to the PTSLac family.The study of LM LIPI-4is important for further understanding of the pathogenicity of LM.