PDF(Pubmed)
Abstract：
Reported herein is the development of assays for the spectrophotometric quantification of biocatalytic silicon-oxygen bond hydrolysis. Central to these assays are a series of chromogenic substrates that release highly absorbing phenoxy anions upon cleavage of the sessile bond. These substrates were tested with silicatein, an enzyme from a marine sponge that is known to catalyse the hydrolysis and condensation of silyl ethers. It was found that, of the substrates tested, tert-butyldimethyl(2-methyl-4-nitrophenoxy)silane provided the best assay performance, as evidenced by the highest ratio of enzyme catalysed reaction rate compared with the background (uncatalysed) reaction. These substrates were also found to be suitable for detailed enzyme kinetics measurements, as demonstrated by their use to determine the Michaelis-Menten kinetic parameters for silicatein.
摘要：
本文报道了用于生物催化的硅-氧键水解的分光光度定量测定的开发。这些测定的核心是一系列显色底物,其在固着键裂解时释放高度吸收的苯氧基阴离子。这些底物用硅酸盐进行了测试，一种来自海洋海绵的酶，已知催化甲硅烷基醚的水解和缩合。结果发现,测试的基材，叔丁基二甲基（2-甲基-4-硝基苯氧基）硅烷提供了最佳的测定性能，与背景（未催化）反应相比，酶催化的反应速率最高。还发现这些底物适用于详细的酶动力学测量，正如它们用于确定硅酸盐的Michaelis-Menten动力学参数所证明的那样。
