依赖PQQ甲醇脱氢酶对底物催化专一性差的原因分析  

CAUSE ANALYSIS OF POOR SUBSTRATE CATALYTIC SPECIFICITY OF PQQ-DEPENDENT METHANOL DEHYDROGENASE

作　　者：王冠芳[1] 王银善[2] 徐宁[1] 赵永芳[1] 

机构地区：[1]武汉大学生物化学与生物物理学系,湖北武汉430072 [2]中国科学院武汉病毒研究所,湖北武汉430071

出　　处：《微生物学杂志》2002年第1期4-6,共3页Journal of Microbiology

基　　金：国家自然科学基金资助项目 ( 3970 0 0 9)

摘　　要：采用甲基营养杆菌NO .2为实验菌株 ,经超声波破细胞 ,酸处理 ,DEAE 纤维素和CM 纤维素柱层析等改进的纯化程序 ,可得到比活力为 12 .5u/mg的甲醇脱氢酶 (MDH)样品。该酶在测活系统中除能氧化甲醇等醇类化合物外 ,还能以较大速率氧化氯化铵、甲胺、脲等物质 ,MDH对不同底物亲和力的差异性主要取决于其辅基吡咯喹啉醌 (PQQ)与底物的结合力。Sample of a kind of methanol dehydrogenase (MDH) with specific activity of 12.5 u/mg and containing pyrroloquinoline quinone (PQQ) from cell extract of methylotrophic bacteria NO.2 was obtained through improved purifying procedure: cell disruption by sonication, acid treatment, DEAE-sephacel and CM-sephacel. The enzyme not only oxidizes methyl alcohol but also oxidizes NH 4Cl, methylamine, urea and other compounds with fairly high speed. The MDH showed different affinity to different substrates that mainly much to do with its affinity of PQQ to the compounds. Before and after combining with substrate, the MDH showed a certain differences in spectrum on specific area.

关 键 词：甲醇脱氢酶 底物专一性 光谱差异 催化 PQQ 辅基 

分 类 号：Q936[生物学—微生物学]