肽聚糖诱导芽孢萌发途径中PrkC激酶参与的信号传递分子机制

In the food industry, it is difficult to efficiently kill these extremely resistant dormant spores, which are major agents of food spoilage. For this, the spore germination is an important method for resolving the crucial issue. The previous studies show that the process of the spore germination is triggered by cell wall peptidoglycan fragments, which is a different mechanism, and they can interactive with an arginine residue, Arg500, belonging to the PASTA domains of the serine/threonine protein kinase PrkC. However, the signaling pathway mechanism of the spore germination induced by peptidoglycan fragments remains unclear. In the study, we will use Bacillus subtilis as the research object, screen the interaction proteins of kinase PrkC by the yeast two-hybrid technology, and testify the phosphorylation of its interaction proteins from kinase PrkC in vitro. Then, construct the mutant spores, analyze their germination efficiency with the treatment of peptidoglycan fragments, and identificate the interaction proteins of kinase PrkC involving in the signaling pathway of the spore germination induced by peptidoglycan fragments. All the results would clarify the molecular mechanism by kinase PrkC, indicate the signaling pathway of the spore germination induced by peptidoglycan fragments, and provide theoretical basis for the search of targeted inducer and repressor about the process of spore germination.

在食品工业中，芽孢引起的食品腐败问题是亟待解决的科学难题，而芽孢萌发是解决这一难题的关键途径。有研究表明肽聚糖诱导的芽孢萌发是一条全新的作用机制，它可以与丝氨酸/苏氨酸激酶PrkC的PASTA结构域上的精氨酸结合，但是肽聚糖诱导芽孢萌发的信号传递机制还不太清楚。本研究以枯草芽孢杆菌为研究对象，利用酵母双杂交系统筛选PrkC的互作蛋白，通过体外磷酸化实验验证并探讨PrkC对互作蛋白的磷酸化作用机制。进一步构建互作蛋白突变体芽孢，分析肽聚糖片段对其萌发的影响，确定参与肽聚糖芽孢萌发途径的PrkC互作蛋白。以上的实验结果可以进一步阐明PrkC作用的分子机制，揭示肽聚糖诱导芽孢萌发的信号传递途径，为找到靶向的芽孢萌发诱导物和阻遏物提供理论基础。