论文部分内容阅读
目的通过构建金黄色葡萄球菌(SAU)ltaS突变株以及体外重组表达其胞外形式的eLtaS蛋白,研究LtaS以及eLtaS蛋白在SAU中的生物学功能。方法利用同源重组的方法构建SAU 8325-4来源的ltaS缺失突变菌株,并对其生长以及外毒素水平进行检测;同时,在大肠杆菌中,体外重组表达并纯化eLtaS蛋白,继而观察其对SAU生长的影响。结果在SAU 8325-4中成功构建了ltaS缺失突变菌株,并发现ltaS突变株生长较野生型菌株缓慢;通过表达纯化成功获得高纯度的eLtaS蛋白,其与突变株共培养后对突变株的生长缓慢现象没有回复作用。结论 LtaS蛋白在SAU侵袭机体的过程中发挥着重要的功能,其胞外形式的eLtaS蛋白可能未参与脂磷壁酸(lipotei-choic acid,LTA)的合成。
OBJECTIVE: To study the biological function of LtaS and eLtaS in SAU by constructing Staphylococcus aureus (SAU) ltaS mutants and expressing the extracellular eLtaS protein in vitro. Methods The homologous recombination method was used to construct the ltaS deletion mutant strain of SAU 8325-4, and its growth and exotoxin levels were detected. In the meantime, eLtaS protein was expressed and purified recombinantly in vitro, and then its effect on SAU The impact of growth. Results The ltaS deletion mutant was successfully constructed in SAU 8325-4. The mutant of ltaS was found to be slower than the wild-type strain. The purified eLtaS protein was successfully obtained by co-culture with the mutant strain. Slow phenomenon does not respond. Conclusions LtaS protein plays an important role in the process of SAU invasion. The extracellular form of eLtaS protein may not be involved in the synthesis of lipotei-choic acid (LTA).