耐辐射奇球菌类胡萝卜素C3',4'-脱氢酶底物特异性

Substrate specificity of carotenoid 3',4'-desaturase from Deinococcus radiodurans

摘要:

为了鉴定耐辐射奇球菌类胡萝卜素C3',4'-脱氢酶 (DR2250) 催化底物的特异性，利用PCR方法将dr2250基因的克隆到载体pUC19上，形成了重组载体pUC-CRTD。利用质粒共转化方法将不同组合的质粒pACCRT-EBIEu、pRK-CRTC和pUC-CRTD转化到大肠杆菌中，筛选阳性克隆并提取其色素进行产物分析。结果表明，DR2250修饰的底物具有选择性，它不能以未经过羟基化修饰的直链类胡萝卜素为底物，而能在C1(1') 羟基修饰的羟基化类胡萝卜素的基础上进行C3',4'-脱氢反应。

Abstract:

To examine the substrate specificity of carotenoid 3',4'-desaturase (DR2250) from Deinococcus radiodurans, we amplified the dr2250 gene by using PCR methods. The PCR products were digested by Hind III-BamH I and ligated into the vector pUC19, yielding recombinant vector pUC-CRTD. We analyzed the carotenoids of E. coli transformants containing pACCRT-EBIEu and (or) pRK-CRTC and (or) pUC-CRTD. Our results demonstrated that DR2250 had substrate specificity on the carotenoids with hydroxyl group at C1 (1').