醇引起酵母醇脱氢酶构象变化的光谱研究

应用紫外、荧光、ＣＤ谱研究了酵母醇脱氢酶经乙醇、正丙醇和乙二醇作用后的构象变化。结果表明２２０ｎｍ、２８０ｎｍ处的紫外吸收，３３６ｎｍ的相对荧光强度随醇浓度增大而加强。ＣＤ谱显示乙醇、乙二醇引起酶分子在２０８ｎｍ、２２０ｎｍ处的双负峰逐渐加强，正丙醇使２２０ｎｍ处负峰加强，２０８ｎｍ处负峰减弱并红移，直至完全消失。上述数据表明醇浓度增加导致酶分子结构逐步松散，同时伴随着活力的丧失。

SPECTRAL STUDY OF THE CONFORMATIONAL CHANGE OF YEAST ALCOHOL DEHYDROGENASE INDUCED BY ALCOHOL

The conformational change of Yeast Alcohol Dehydrogenase (YADH) at the different concentration of ethanol, n-propanol and ethylene glycol was studied by means of ultraviolet spectrum, fluorescence spectrum and circular dichroism spectrum. The results showed that the ultraviolet absorbance at 220nm and 280nm as well as the relative fluorescence intensity at 336nm of YADH increased with increasing alcohol concentration. The negative peakes at 208nm and 220nm of YADH in circular dichroism spectrum with the solvent of ethanol, ethylene glycol were obviously intensified, but the 220nm peak of YADH was increased in the presence of n-propanol while the 208nm peak was decreased and red-shifted in position as to completely lost. According to the data above, it indicates that the conformation of YADH was changed with losing activity at the various concentration of alcohol.