蕹菜叶过氧化物酶功能基团的化学修饰

为研究蕹菜叶面的的功能基团，将分离纯化得到的电泳纯的蕹菜过氧化物酶，分别用乙酰丙酮、顺丁烯二酸酐，二巯基苏糖醇、氯胺-T、溴代乙酸、对氯汞苯甲酸、苯甲基磺酰氟、N-乙酰咪唑选择性地对其进行化学修饰，并测定修饰前后酶活力变化。结果表明：精氨酸残基、赖氨酸残基、组氨酸残基和巯基可能是蕹菜过氧化物酶发挥活性的必需基团，而甲硫氨酸硫醚基、丝氨酸残基和酪氨酸酚羟基可能不是蕹菜过氧化物酶活性中心的必需基团。
In order to identify the functional groups of peroxidase from the leaves of Ipmoea aquatica Forsk， peroxidas were isolated，purifiedandselectively modified by using BD，DTT，pCMB，Maleic anhydride，Chloramine-T，PMSF，NAI and BrAc separately and the change on activity were determined. The result showed that Arg，Lys，His and sulfhydryl involving in the composition of the enzyme active center should be considered as indispensable functional groups of peroxidase，while Met，Ser and Tyr residues should not be because they were not directly related to the activity of peroxidase from Ipomoea aquatica Forsk