摘要
研究β-内酰胺酶催化水解青霉素G钾动力学,用毛细管区带电泳法检测青霉素G钾含量,采用动力学方法考察了反应时间、p H和温度对β-内酰胺酶水解活性和稳定性的影响,并计算一定条件下的动力学参数。结果表明,升高反应温度β-内酰胺酶与底物的亲和力和催化水解的效率逐渐增大,但过高温使酶失活,酶和底物的亲和力和催化效率均迅速降低;p H大小影响β-内酰胺酶中间络合物转变为产物的效率;通过动力学参数计算确定β-内酰胺酶催化水解青霉素G钾的最佳条件为p H8.41、温度40℃,在此条件下水解速率常数越大,β-内酰胺酶水解能力越强,最适条件下β-内酰胺酶的转化率kcat和反应的活化能Ea为29.7 s-1、3186.26 J/mol。
Capillary electrophoresis study on kinetics of hydrolysis reaction of beta-lactamase and penicillin G potassium were investigated. Effects of p H, temperature, reaction time on hydrolysis activities and stabilities of beta-lactamase were studied by kinetics method and series of kinetic parameters were calculated. The experimental results showed that affinity and efficiency of the catalytic hydrolysis of beta-lactamase and substrates were gradually strengthened with the reaction temperature increased, but it were weakened rapidly when there were enzyme inaction in high temperature. The effi ciency of intermediate complexes to transform product was infl uence by p H. The larger the rate constants became, the stronger efficiency became under optimal condition for hydrolysis which were determined as p H 8.41 and temperature 40 ℃ by way of kinetic parameters calculated. Conversion rate（kcat） and activation energy（Ea） for hydrolysis of beta-lactamase were 29.7 s-1, 3186.26 J/mol.
出处
《食品科技》
CAS
北大核心
2015年第5期26-29,共4页
Food Science and Technology
基金
浙江省级公益性技术应用研究计划项目(2012C37055)
国家自然科学基金项目(51201153)
关键词
毛细管电泳
Β-内酰胺酶
青霉素G钾
动力学
capillary electrophoresis
beta-lactamase
penicillin G potassium
kinetics
