Montaine F, Lenders J P, Crichton R R
Eur J Biochem. 1987 Apr 15;164(2):329-36. doi: 10.1111/j.1432-1033.1987.tb11062.x.
An aldehyde derivative of riboflavin was covalently attached by reductive alkylation to soluble polycationic supports. The flavopolymers so obtained were stable under operational conditions. The catalytic efficiency towards oxidation of NADH by these flavopolymers was demonstrated, and the kinetic parameters (Km and kcat) revealed an overall catalytic efficiency (kcat/Km) 185-fold greater compared to riboflavin. Various factors affecting the chemical regeneration of NAD+ from NADH such as pH, ionic strength, nature of the buffer etc. were studied. The most interesting result was the highly favourable influence of borate ions which increased the reaction rate by a factor 2-4 compared to the other buffers. The flavopolymers are very effective for in situ recycling of NAD(P)+. With up to 300-fold NADH----NAD+ conversions for the system using yeast alcohol dehydrogenase and up to 1500-fold NADPH----NADP+ regenerations for the system using glucose-6-phosphate dehydrogenase. These flavopolymers are superior to previous chemical recycling systems.
核黄素的一种醛衍生物通过还原烷基化共价连接到可溶性聚阳离子载体上。如此获得的黄素聚合物在操作条件下是稳定的。证明了这些黄素聚合物对NADH氧化的催化效率，动力学参数（Km和kcat）显示其总体催化效率（kcat/Km）比核黄素高185倍。研究了影响从NADH化学再生NAD+的各种因素，如pH、离子强度、缓冲液性质等。最有趣的结果是硼酸根离子的高度有利影响，与其他缓冲液相比，它使反应速率提高了2至4倍。黄素聚合物对NAD(P)+的原位循环非常有效。使用酵母醇脱氢酶的系统中NADH向NAD+的转化率高达300倍，使用葡萄糖-6-磷酸脱氢酶的系统中NADPH向NADP+的再生率高达1500倍。这些黄素聚合物优于以前的化学循环系统。
