CAREER: Target Specificity of Cysteine Desulfurases in Bacillus Subtilis

含硫的辅助因子参与广泛的基本生物反应。虽然硫一直被认为是蛋白质辅因子不可或缺的，但其与生物分子的结合尚未完全了解。在大多数生物体中，为合成几种辅助因子而招募硫涉及到一种通用酶的参与，即半胱氨酸脱硫酶。因此，这种混杂酶的招募对剖析硫动员的具体机制提出了实验挑战，因为它的失活影响了大多数硫辅因子的合成。另一方面，革兰氏阳性菌，如枯草芽孢杆菌，编码几种不同的半胱氨酸脱硫酶。根据它们的基因组位置、编码序列和初步分析，实验室假设它们在硫代谢中具有专门的功能。结合分子遗传学、生物化学和光谱学方法，实验室将研究这些酶动员硫的特定催化机制，并以枯草芽孢杆菌为模式生物参与硫辅因子的生物合成。该项目将(i)确立半胱氨酸脱硫剂分化和专门化的进化重要性；（ii）定义其结构、机制和功能关系的关键方面；(3)为研究铁硫代谢不耦合的输硫反应提供了一个很好的模型体系。成功的结果将改变我们对维持生命的反应和合成必需硫辅因子代谢途径的交叉点的理解。更广泛的影响这个职业项目的更广泛的影响将包括维克森林大学的研究生和来自邻近机构的本科生参与指导的研究/专业发展计划。由研究生和导师组成的支持团队将为学生制定职业规划，其中包括暑期研究经历和参加专业发展活动以及学年期间的会议。该计划旨在扩大科学研究的准备和科学中代表性不足的群体的参与。团队指导方法也将对参与的研究生及其作为未来教师学者的培训产生影响。

Intellectual MeritSulfur-containing cofactors participate in a wide range of essential biological reactions. Although sulfur has long been recognized as indispensable to protein cofactors, its incorporation into biomolecules is not completely understood. In most organisms, the recruitment of sulfur for the synthesis of several cofactors involves the participation of a single general enzyme, cysteine desulfurase. The recruitment of such a promiscuous enzyme therefore poses an experimental challenge for dissecting the specific mechanisms of sulfur mobilization because its inactivation affects the synthesis of most sulfur cofactors. Gram-positive microbes such as Bacillus subtilis, on the other hand, code for several distinct cysteine desulfurases. Based on their genomic location, coding sequences, and preliminary analyses, the lab hypothesizes that each has specialized functions in sulfur metabolism. Using a combination of molecular genetics, biochemical and spectroscopic approaches, the lab will investigate the specific catalytic mechanisms by which these enzymes mobilize sulfur and their participation in the biosynthesis of sulfur cofactors using Bacillus subtilis as the model organism. This project will (i) establish the evolutionary importance of the differentiation and specialization of cysteine desulfurases; (ii) define key aspects of their structural, mechanistic, and functional relationships; and (iii) provide an excellent model system to study sulfur-trafficking reactions uncoupled from iron-sulfur metabolism. Successful results will transform our understanding of life-sustaining reactions and the intersections of metabolic pathways in the synthesis of essential sulfur cofactors.Broader ImpactThe broader impacts of this CAREER project will include the involvement of graduate students from Wake Forest University and undergraduate students from neighboring institutions in a mentored research/professional development program. The support team comprised of graduate students and instructors will develop a career plan for the students, which will include summer research experience and participation in professional development activities and meetings during the academic year. This program aims to broaden the scientific research preparation and participation of underrepresented groups in science. The team-mentoring approach will also have an impact on participating graduate students and their training as future teacher-scholars.