CAJ | 학술논문

为探究单增李斯特菌 inlB 基因缺失株的生物学特性，利用同源重组技术成功构建了 inlB 基因突变株（LM90-△inlB）。对突变株进行了溶血试验、细菌计数小鼠肝、脾和脑载菌试验测定、体外耐酸碱生长培养试验及鼠脑微血管内皮细胞侵袭、黏附、增殖试验。结果显示，突变株溶血活性无变化；小鼠肝脏载菌量突变株低于亲本株，但差异不显著，脾脏载菌量无差异；突变株的毒力显著降低，对小鼠半数致死剂量比野生型菌株有明显升高（P ＜0．05）；在体外耐酸碱生长能力培养中，inlB 突变株耐酸性没有改变，而耐碱能力强于亲本株；细胞黏附侵袭及增殖试验表明突变株明显低于亲本株（P ＜0．05）。说明 inlB 基因对 LM90的毒力具有一定的调控作用，结果对于阐明 LM 毒力因子的致病机理提供了科学依据。
위탐구단증리사특균 inlB 기인결실주적생물학특성，이용동원중조기술성공구건료 inlB 기인돌변주（LM90-△inlB）。대돌변주진행료용혈시험、세균계수소서간、비화뇌재균시험측정、체외내산감생장배양시험급서뇌미혈관내피세포침습、점부、증식시험。결과현시，돌변주용혈활성무변화；소서간장재균량돌변주저우친본주，단차이불현저，비장재균량무차이；돌변주적독력현저강저，대소서반수치사제량비야생형균주유명현승고（P ＜0．05）；재체외내산감생장능력배양중，inlB 돌변주내산성몰유개변，이내감능력강우친본주；세포점부침습급증식시험표명돌변주명현저우친본주（P ＜0．05）。설명 inlB 기인대 LM90적독력구유일정적조공작용，결과대우천명 LM 독력인자적치병궤리제공료과학의거。
In order to evaluate the biological characteristics of a gene-mutant strain of Listeria monocyto-genes with a deletion of inlB,based on homologous recombination technology,we constructed a gene-mu-tant strain (LM90-△inlB)of Listeria monocytogenes .The hemolysis,bacterial counts in liver,spleen,brain of mice,determination of LD50 and resistance to acid,base in vitro were tested,the ability of LM90, LM90-△inlB for adhesion,invasion,the intracellular growth in mouse brain microvascular endothelial cells (MBMEC)was detected.The haemolytic activity of mutant strain was the same to parent strain,total bac-terial counts of mutant strain in liver were lower than that of parent strain,but no significant difference. The bacterial count in spleen was no different.The virulence of mutant strain was reduced significantly and its 50% lethal dose in mice was increased obviously compared to the parent strain.The resistance to acid of mutant strain was same as that of parent strain but the resistance to base was weaker than that of parent strain in vitro .There were significant differences in the adhesion,invasion,intracellular growth between LM90 and LM90-△inlB in MBMEC.Collectively,these results indicated that the inlB gene can regulate the virulence of LM90,which will provide scientific evidence for clarifying the pathogenesis of LM viru-lence factor.