Efficient Binding of Flexible and Redox-Active Coenzymes by Oxidoreductases

详细信息    查看全文

• 作者：C. Satheesan Babu ; Carmay Lim
• 刊名：ACS Catalysis
• 出版年：2016
• 出版时间：June 3, 2016
• 年：2016
• 卷：6
• 期：6
• 页码：3469-3472
• 全文大小：300K
• 年卷期：0
• ISSN：2155-5435

文摘

Although how an enzyme binds its substrate and rate-limiting transition state is well-studied, how it binds a flexible redox-active coenzyme, which may adopt different native solution conformations when oxidized/reduced, remains unclear. Using the coenzyme nicotinamide adenine dinucleotide (NAD) as an example, we show that redox enzymes bind oxidized NAD⁺ and reduced NADH in similar conformations that are between folded NAD⁺ and extended NADH solution conformations. By preorganizing the coenzyme-binding site to bind such an “intermediate” conformation, a redox enzyme can efficiently bind oxidized and reduced NAD, whereas having to substantially reorganize the binding site to accommodate the NAD product might impede catalysis.