Bacillithiol and the Redox Biology of Bacillus Subtilis

该项目正在探索允许细胞保护胞浆蛋白免受化学修饰的生物学机制。这些生物学机制对于细胞避免损伤至关重要，例如，由于氧化应激或暴露于有毒重金属。 胞质蛋白通常含有还原的半胱氨酸残基，其含有巯基官能团（RSH）。这些基团容易被活性氧和氮物质、亲电体以及有毒金属和准金属修饰。细胞含有丰富的低分子量硫醇化合物，用于缓冲这些反应性化学物质的有害影响，也可能参与受损蛋白质的修复。在许多细胞中，这种作用是由谷胱甘肽（GSH），一种含半胱氨酸的三肽发挥的。许多革兰氏阳性菌（厚壁菌门）缺乏GSH，这种保护作用由杆菌硫醇（BSH）承担，BSH是一种最近表征的含有半胱氨酸、葡糖胺和苹果酸的化合物。本研究探讨了BSH在模式生物枯草芽孢杆菌中的不同作用。BSH在保护免受活性氧化合物（包括过氧化物和次氯酸），亲电试剂（甲基乙二醛，甲醛）和有毒类金属的作用正在使用遗传，生理和生化方法进行研究。BSH是某些解毒酶所需的共底物，其化学性质和对金属离子的亲和力与GSH不同。BSH在不同细菌中的存在表明，通过对这种新型硫醇的详细表征建立的范例具有深远的影响。 该项目涉及生物化学、遗传学、基因组学和生理学方法的组合。这些结果将对生物系统包括与医疗和农业问题有关的生物系统产生普遍影响。实验工作由本科生，研究生和博士后学生进行，他们将接受多学科方法的广泛培训，以研究细菌生理学。 学生采用最先进的转录谱分析，蛋白质组学，化学和生物物理技术，并获得分析和解释所得数据的经验。各级学生在小组会议和部门研讨会以及区域，国家和国际会议上展示他们的工作，无论是海报还是口头报告。学生准备手稿草稿，并参与出版过程的各个阶段。此外，学生们被期望积极作为实验室的新成员的导师。最后，学生有机会与具有类似研究兴趣的合作实验室进行互动，并了解相关生物体中正在进行的互补项目。谁曾在这个项目上工作过以前的学生已经在学术界和工业界的成功职业生涯。

This project is exploring the biological mechanisms that allow cells to protect cytosolic proteins against chemical modification. These biological mechanisms are critical for cells to avoid damage, for example, due to oxidative stress or exposure to toxic heavy metals. Cytosolic proteins often contain reduced cysteine residues which contain a thiol functional group (RSH). Such groups are susceptible to modification by reactive oxygen and nitrogen species, electrophiles, and toxic metals and metalloids. Cells contain abundant, low molecular mass thiol compounds that serve to buffer the harmful impact of these reactive chemicals and may also participate in the repair of damaged proteins. In many cells, this role is played by glutathione (GSH), a cysteine-containing tripeptide. Many Gram positive bacteria (phylum Firmicutes) lack GSH and this protective role is assumed by bacillithiol (BSH), a recently characterized compound containing cysteine, glucosamine, and malic acid. This research explores the diverse roles of BSH in the model organism Bacillus subtilis. The role of BSH in protection against reactive oxygen compounds (including peroxides and hypochlorous acid), electrophiles (methylglyoxal, formaldehyde), and toxic metalloids are being investigated using genetic, physiological, and biochemical methods. BSH is a required co-substrate for some detoxification enzymes and differs from GSH in its chemical properties and affinity for metal ions. The presence of BSH in diverse bacteria argues that the paradigms established by a detailed characterization of this novel thiol are having far-reaching implications. Broader impacts This project involves a combination of biochemical, genetic, genomic, and physiological approaches. The results will have general implications for biological systems including those pertaining to medical and agriculture problems. The experimental work is conducted by undergraduate, graduate, and post-doctoral students who will receive broad training in multidisciplinary approaches to investigating bacterial physiology. Students employ state-of-the-art transcriptional profiling, proteomics, chemical and biophysical techniques and gain experience in analyzing and interpreting the resulting data. Students at all levels present their work locally during group meetings and in department seminars and at regional, national, and international conferences as either posters or oral presentations. Students prepare drafts of manuscripts and are involved in all stages of the publishing process. In addition, students are being expected to be active as mentors to new members of the laboratory. Finally, students have the opportunity to interact with collaborating laboratories with similar research interests and learn about ongoing, complementary projects in related organisms. Previous students who have worked on this project have gone on to successful careers in academics and industry.