Mycobacterial Sulfation Pathways

描述（由申请人提供）：本项目的长期目标是研究硫酸化和含硫代谢产物在结核分枝杆菌（M. tuberculosis）生命周期和发病机制中的作用。tb）。世界卫生组织已宣布分枝杆菌病原体为全球性紧急情况，特别是关于M。tb和M.与艾滋病的关系多重耐药菌株的出现，无论是M。tb和M. Avium进一步增加了对新的治疗途径的需求。M.结核病感染是一个复杂的过程，包括在肺巨噬细胞内停留，刺激免疫反应和形成肉芽肿，进入潜伏期，并最终从潜伏期出现以产生活动性结核病。病原体与其宿主之间的复杂相互作用是维持生命周期各个阶段所必需的。这个项目是由我们在分枝杆菌基因组中发现的假定的磺基转移酶和硫酸酯酶发起的。在分枝杆菌中已经鉴定出少数硫酸化代谢物，包括丰富的细胞壁糖脂硫脂-1（SL-1），但其功能尚不清楚。在真核生物中，已知硫酸化代谢物在细胞间通讯中发挥作用。因此，我们推测分枝杆菌中的硫酸化代谢产物可能参与宿主-病原体相互作用。最后一个授权期集中在三个特定目标：1）确定分枝杆菌硫转移酶的功能; 2）研究分枝杆菌硫酸酯酶的功能; 3）确定结核分枝杆菌中的硫同化途径。在下一个资助期内，我们计划继续我们对分枝杆菌硫酸盐代谢机制的研究。我们将研究硫酸化代谢产物和相关的生物合成酶在两种M。tb和M. avium（Aim 1）。我们将学习M。在基于细胞的试验和免疫受损小鼠中检测结核杆菌硫酸化突变体，以评估与适应性和先天免疫机制的相互作用（目的2）。APS还原酶的小分子抑制剂将被用作功能研究的工具和药物开发的先导（目标3）。最后，我们将进一步表征分枝杆菌甲酰甘氨酸生成酶和硫酸酯酶（目的4）。

DESCRIPTION (provided by applicant): The long-term objective of this project is to study the roles of sulfated and sulfur-containing metabolites in the life cycle and pathogenesis of Mycobacterium tuberculosis (M. tb). Mycobacterial pathogens have been declared a global emergency by the World Health Organization, particularly in regard to the deadly synergy of M. tb and M. avium with AIDS. The emergence of multidrug resistant strains of both M. tb and M. avium has further escalated the need for new therapeutic avenues. M. tb infection is a complex process that involves residence within lung macrophages, stimulation of an immune response and the formation of granulomas, entry into a latent phase and, ultimately, emergence from latency to produce active tuberculosis. Complex interactions between the pathogen and its host are required to sustain the various stages of the life cycle. This project was initiated by our discovery of putative sulfotransferases and sulfatases in mycobacterial genomes. A handful of sulfated metabolites had been identified in mycobacteria, including the abundant cell wall glycolipid sulfolipid-1 (SL-1), but their functions were unknown. In eukaryotes, sulfated metabolites are known to play roles in cell-cell communication. We therefore speculated that the sulfated metabolites in mycobacteria may be involved in host-pathogen interactions. The last granting period focused on three Specific Aims: 1) define the functions of mycobacterial sulfotransferases; 2) investigate the functions of mycobacterial sulfatases; and 3) define the sulfur assimilation pathway in Mycobacterium tuberculosis. In the next granting period we plan to continue our studies of the mycobacterial sulfate metabolic machinery. We will investigate the biological roles of sulfated metabolites and the associated biosynthetic enzymes in both M. tb and M. avium (Aim 1). We will study M. tb sulfation mutants in cell-based assays and immune-compromised mice in order to assess interactions with adaptive and innate immune mechanisms (Aim 2). Small molecule inhibitors of APS reductase will be sought as tools for functional studies and leads for drug development (Aim 3). Finally, we will further characterize mycobacterial formylglycine generating enzymes and sulfatases (Aim 4).