Sapienza Paul J, Lee Andrew L
Division of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA.
Biomol NMR Assign. 2014 Apr;8(1):195-9. doi: 10.1007/s12104-013-9482-6. Epub 2013 May 9.
Thymidylate synthase (TSase) is a 62 kDa homodimeric enzyme required for de novo synthesis of thymidine monophosphate in most organisms. This makes the enzyme an excellent target for anticancer and microbial antibiotic drugs. In addition, TSase has been shown to exhibit negative cooperativity and half-the-sites reactivity. For these collective reasons, TSase is widely studied, and much is known about its kinetics and structure as it progresses through a multi-step catalytic cycle. Recently, nuclear magnetic resonance spin relaxation has been instrumental in demonstrating the critical role of dynamics in enzyme function in small model systems. These studies raise questions about how dynamics affect function in larger enzymes with more complex reaction coordinates. TSase is an ideal candidate given its size, oligomeric state, cooperativity, and status as a drug target. Here, as a pre-requisite to spin relaxation studies, we present the backbone and ILV methyl resonance assignments of TSase from Escherichia coli bound to a substrate analogue and cofactor.
胸苷酸合成酶（TSase）是一种62 kDa的同二聚体酶，在大多数生物体中，它是从头合成胸苷一磷酸所必需的。这使得该酶成为抗癌和抗微生物抗生素药物的理想靶点。此外，已证明TSase表现出负协同性和半位点反应性。基于这些综合原因，TSase受到广泛研究，并且随着它经历多步催化循环，人们对其动力学和结构了解很多。最近，核磁共振自旋弛豫在证明动力学在小模型系统中酶功能中的关键作用方面发挥了重要作用。这些研究提出了关于动力学如何影响具有更复杂反应坐标的更大酶的功能的问题。鉴于TSase的大小、寡聚状态、协同性以及作为药物靶点的地位，它是一个理想的候选对象。在这里，作为自旋弛豫研究的先决条件，我们给出了来自大肠杆菌的与底物类似物和辅因子结合的TSase的主链和异亮氨酸、亮氨酸、缬氨酸甲基共振归属。
