十二烷基硫酸铵对烟草多酚氧化酶的激活作用

本文对从新鲜烟叶中分离纯化了两种多酚氧化酶,分别命名为多酚氧化酶(PPO )和多酚氧化酶(PPO ),并对其活性做了深入研究,发现对大多数蛋白质有抑制作用的十二烷基硫酸钠(SDS)对其有激活作用。在SDS浓度为0.5mM的条件下,PPO 和PPO 的活性分别提高了50%和86%。在pH值为6.5,T=50℃时PPO 的活性达到最大,在此条件下加入SDS后PPO 的活性提高了29.6%。SDS与PPO 的物质的量比在1.2时,PPO 的活性达到最大。

Activation of SDS on Polyphenol Oxidase from Nicotiana Tobacum

Two kinds of polyphenol oxidase were purified from leaves of nicotiana tobacum and named as PPOⅠ and PPOⅡ. The activation of SDS which has inhibitory effects on most protein was found. With 0.5M SDS, the activity of PPOⅠ and PPOⅡ were increased by 50% and 86% respectively. With 50 centigrade, pH6.5, the activity of PPO reached the highest level. After the addition of SDS, the activity of PPOⅡ was increased by 29.6%. The optimal molar ratio of SDS to PPOⅡ was 1.2∶1.