结核分枝杆菌ESX-4分泌系统研究进展

Progress in the ESX-4 secretion system of Mycobacterium tuberculosis

摘要:

结核分枝杆菌(Mycobacterium tuberculosis)是引发结核病的主要病原菌，其复杂的分泌系统在致病过程中发挥关键作用。近年，ESX-4分泌系统备受关注。本文首先阐述了其编码基因结构组成与进化、蛋白组成与功能、底物识别与转运机制、转录调控等，重点分析了ESX-4分泌系统如何主导其他ESX分泌系统的分泌功能，以及该系统在调控宿主细胞死亡、参与铁利用等方面的生理功能。在此基础上，通过对现有研究的分析，揭示了ESX-4分泌系统可能涉及结核分枝杆菌重要毒力因子蛋白酪氨酸磷酸酶(protein tyrosine phosphatase A, PtpA)的分泌。最后，针对该分泌系统未来研究方向进行了展望，旨在为深入研究该分泌系统的功能，并靶向该分泌系统进行药物设计及疫苗开发提供参考。

Abstract:

Mycobacterium tuberculosis is the main pathogen causing tuberculosis, and its complex secretion system plays a key role in the pathogenic process. In recent years, the ESX-4 secretion system has attracted much attention. This paper introduces the ESX-4 secretion system from the structures and evolution of its coding genes, protein composition and functions, substrate recognition and transport mechanisms, and transcriptional regulation. It focuses on how the ESX-4 secretion system guides the secretion functions of other ESX secretion systems, and its physiological functions in regulating the death of host cells and participating in iron utilization. On this basis, the analysis of existing studies reveals that ESX-4 secretion system may be involved in the secretion of protein tyrosine phosphatase A (PtpA), a key virulence protein of Mycobacterium tuberculosis. Finally, this paper makes an outlook on the future research directions of the secretory system, aiming to provide some reference for in-depth study of the function of the secretory system and for drug design and vaccine development targeting the secretory system.