Delgoda Rupika, Lian Lu Yun, Sandy James, Sim Edith
Department of Pharmacology, University of Oxford, Mansfield Road, UK.
Biochim Biophys Acta. 2003 Mar 17;1620(1-3):8-14. doi: 10.1016/s0304-4165(02)00500-7.
Arylamine N-acetyltransferases (NAT) are a family of enzymes found in both eucaryotes and procaryotes, which catalyse the N-acetylation of a range of arylamine and hydrazine drugs and carcinogenic arylamines, using acetyl Coenzyme A as a cofactor. Here we describe a nuclear magnetic resonance (NMR) investigation of the interaction of substrates with Salmonella typhimurium NAT. For solution NMR investigations, pure recombinant NAT from S. typhimurium was used at up to 0.1 mM. We demonstrate that a hydrazine substrate, isoniazid (INH), binds to the protein in the absence of the cofactor, acetyl CoA, and thereby suggest that even though the catalysis may follow a ping-pong pathway, ligand-enzyme interactions can occur in the absence of acetyl CoA.
芳胺N-乙酰基转移酶（NAT）是一类在真核生物和原核生物中均存在的酶，它们以乙酰辅酶A作为辅因子，催化一系列芳胺和肼类药物以及致癌性芳胺的N-乙酰化反应。在此，我们描述了一项关于底物与鼠伤寒沙门氏菌NAT相互作用的核磁共振（NMR）研究。对于溶液NMR研究，使用了浓度高达0.1 mM的来自鼠伤寒沙门氏菌的纯重组NAT。我们证明，在没有辅因子乙酰辅酶A的情况下，肼类底物异烟肼（INH）会与该蛋白质结合，从而表明即使催化过程可能遵循乒乓途径，但在没有乙酰辅酶A的情况下也可能发生配体-酶相互作用。
