论文部分内容阅读
研究了小麦 (Triticum aestivum L. cv. Yangmai 158)叶片暗诱导衰老期间内肽酶同工酶的变化及其部分生化特性,发现叶片衰老期间,内肽酶活性升高,同时出现5种新的内肽酶同工酶(EP1、EP2、EP4、EP5、EP6)。6-苄氨基嘌呤(6-BA)处理能延缓这些同工酶的出现,而脱落酸(ABA)处理则加速它们的表达。衰老期间小麦叶片内的6种内肽酶同工酶(EP1-EP6)中的EP1、EP2、EP4、EP5、EP6呈现活性的pH及温度范围较窄,而EP3有活性的pH范围和温度范围均较宽,且EP3在嫩叶、老叶中均有活性。另外,EP3、EP5、EP6对热不太敏感。蛋白酶抑制剂实验表明,EP1、EP2 是需金属离子的半胱氨酸型内肽酶,EP4是丝氨酸型内肽酶。
The change of endopeptidase isoenzyme and its partial biochemical characteristics during the dark-induced senescence of wheat leaves (Triticum aestivum L. cv. Yangmai 158) were studied. It was found that endopeptidase activity increased during leaf senescence and five new Endopeptidase isoenzymes (EP1, EP2, EP4, EP5, EP6). Treatment with 6-benzylaminopurine (6-BA) delayed the appearance of these isozymes, while abscisic acid (ABA) treatment accelerated their expression. EP1, EP2, EP4, EP5, EP6 of 6 endopeptidase isoenzymes (EP1-EP6) in wheat leaves during senescence exhibited a narrower pH and temperature range while EP3 had an active pH range and temperature range Are wide, and EP3 in young leaves, old leaves are active. In addition, EP3, EP5, EP6 are less sensitive to heat. Protease inhibitors experiments show that, EP1, EP2 is a metal ion-requiring cysteine endopeptidase, EP4 is serine-type endopeptidase.