泛醌结合蛋白（QPs）羧基的化学修饰与重组活性

Chemical Modification of Q-binding Protein (QPs) and Its Reconstitutive Activity

研究了羧基修饰剂ＤＣＣＤ对泛醌结合蛋白ＱＰｓ重组活力的影响；用０．１％ＴｒｉｔｏｎＸ－１００增溶ＱＰｓ后，用２５０ｍｏｌ／ｍｏｌＱＰｓ的ＤＣＣＤ于室温处理５ｍｉｎ，处理后的ＱＰｓ丧失约５０％与琥珀酸脱氢酶的重组活力。先将ＱＰｓ与琥珀酸脱氢酶重组再用ＤＣＣＤ处理没有发现重组的琥珀酸泛醌还原酶活性的降低。此结果说明ＱＰｓ中存在重组活性必需的羧基。

QPs was named as the Q-binding protein in succinate-Q reductase. It was isolated in 1980 by several laboratories. QPs can be reconstituted with succinate dehydrogenase (SDH) to become the reconstitutively active succinate-Q reductase. Some amino groups in succinate dehydrogenase was found to be necessary for the activity of reconstitution.This result implicated that in QPs there must be some negative charged groups which were necessary for the reconstitution.DCCD was used to modify the carboxyl groups of QPs,and proved that some carboxyl groups were responsible for the reconstitutive activity.