摘要
紫外差光谱是研究蛋白质在溶液中构象的有用工具,能揭示蛋白质中多种生色的氨基酸残基的存在和状态,并广泛用于多种酶类的必要基团、作用机理、过液态的存在等多方面的研究。前报I已证明,激活剂LIA能显著提高溶菌酶的活力,且是以无竞争的方式,随机地与溶菌酶结合的机理使其催化能力成倍地提高。显然,激活剂的加入使溶菌酶的结构,特别是在溶液中的空间构象发生了有利于催化作用的变化。为了弄清LIA诱导的溶菌酶构象的变化及在激活作用中所涉及的分子机理,我们进一步探索了溶菌酶与激活剂,底物相互作用的紫外差光谱。
The Ultraviolet difference absorption spectra of lysozme from egg white induced by inactive lysozyme, substrate, and activator was respectively investigated. The inactive enzymes produced characteristic ultraviolet difference spectra with negative value at all. The spectra produced by activator indicated that there were absorption peaks at 270- 293 nm on ultraviolet different spectra, and it proved that the tryptophan which resedues as binding site of lysozyme was activited. The diffferent ultraviolet of differnce spectra induced by lysozyme+substrate and lysozyme+activator+substrate was measured. The peak of the latter was more blue than that of the former, but the absorption value of the latter was much higher than that of the former. The highest absorption value of lysozyme with activator at 281.5nm was about 0.7mg/ml activator. The activity mechanism with activator was also discussed.
出处
《贵州科学》
1990年第3期43-47,共5页
Guizhou Science
