Structural Biology of Biosynthetic Enzymes

该计划项目的目标是发现和表征新的膦酸盐，这些天然产物的生物合成所涉及的酶的生物化学和结构生物学表征大大受益。此外，详细了解与其同源底物/抑制剂复合的此类酶的三维结构可有助于这些催化剂的工程化以产生具有改善的生物学和/或药代动力学性质的衍生化合物。在下一个周期中，我们将研究目标扩展到生物化学领域， 参与抗细菌的plumbemycin和抗真菌的rhizoctlcin的生物合成的基因簇的表征。来自这些簇的酶指导两种天然产物的生产，所述天然产物由共同的弹头（苏氨酸合成酶抑制剂（Z）-L-2-氨基-5-膦酰基-3-戊烯酸（APPA））组成，但具有不同的基于肽的递送载体。我们将进行来自这些簇中的每一个的单个酶的体外重构，并利用这一知识来生产APPA的另外的肽和非肽衍生物，其可以靶向一系列蛋白质。 其他病原微生物。同时，我们的目标也是继续我们的几个生物合成酶的结构功能研究，其特征在于在初始周期。最后，我们还将描述生产生物体利用的耐药机制，并可能限制几种膦酸盐的生物学效用。

The Program Project goals towards the discovery and characterization of novel phosphonates have benefited significantly from biochemical and structural biological characterization oif the enzymes involved in the biosynthesis of these natural products. Additionally, detailed knowledge of the three dimensional structures of such enzymes in complex with their cognate substrates/inhibitors can aid in the engineering of these catalysts to yield derivative compounds with improved biological and/or pharmacokinetic properties. In this next cycle, we expand our research aims towards the biochemical characterization of gene clusters involved in the biosynthesis of the antibacterial plumbemycin and the antifungal rhizoctlcin. The enzymes from these clusters direct the production of two natural products consisting of a common warhead (the threonine synthase inhibitor (Z)-L-2-amino-5-phosphono-3-pentenoic acid (APPA)) but with different peptide-based delivery vehicles. We will carry out in vitro reconstitution of individual enzymes from each of these clusters and utilize this knowledge for the producfion of addifional pepfidic and non-peptidic derivatives of APPA that can target a range of additional pathogenic organisms. Concurrently, we also aim to continue our structure-function studies of several of the biosynthetic enzymes that have been characterized during the initial cycle. Lastly, we will also characterize the mechanisms of resistance that are utilized by the producing organisms and may limit the biological utility of several phosphonates.