溴化+烷基三甲基铵滴定时氨基酰化酶的失活与构象变化的比较

研究了阳离子去污剂-溴化+烷基三甲基铵变性时氨基酰酶的失活与构象变化.当用溴化+烷基三甲基铵滴定氨基酰化酶时,随着去污剂浓度增大,酶的活力逐渐丧失,至50mmolL时酶完全失活.用荧光发射光谱(295nm激发)的方法监测了氨基酰化酶的构象变化.发现氨基酰化酶失活先于构象变化.从这一结果看来.金属酶的活性部位构象可能也是比整个分子的构象具有较大的柔性或运动性.

INACTIVATION AND CONFORMATIONAL CHANGES OF AMEVOACYLASE DURING DECYLTRIMETHYL AMINONIUM BROMIDE TITRATION

The inactivation and conformational changes of aminoacylase during denaturation by detergent decyltrimet yl aminonium bromide have been studied. The enzyme activity decreased with increasing of detergent concentration and was inactivated completely at a comcentration of 50mmol/L . The conformational changes of aminoacylase during denaturation at different concentrations of decyltrimethyl aminonium bromide have been determined by fluorescence emission spectra. With the increase of concentration of detergent fluorescence emission intensity decreased and reached the minimum at a detergent concentration of 220mM. Results showed that the inactivation of enzyme was prior to its conformational changes. It suggests that the active site of aminoacylase may be more flexible than the whole molecule.