大连工业大学学报2025，Vol.44Issue(2)：103-108,6.DOI:10.19670/j.cnki.dlgydxxb.2025.0205
甲基黄嘌呤N7-脱甲基酶CdnC的可溶性表达及其酶学性质
Soluble expression and enzymatic properties of methylxanthine N7-demethylase CdnC
摘要
Abstract
A methylxanthine N7-demethylase named as CdnC that produced by the caffeine-degrading bacterium Paraburkholderia caffeinilytica CF1,was successfully expressed and purified by codon optimization and the pMAL-c5X expression vector.CdnC shows substrate specificity and works together with oxidoreductase CdnD and glutathione s-transferase CdnE to remove the N7 methyl group of 7-methylxanthine,but not 3,7-dimethylxanthine and 1,7-dimethylxanthine.CdnC-MBP was identified by SDS-PAGE and molecular size chromatography as a monomer protein with a molecular weight of 76.3 ku.The enzymatic characterization of CdnC revealed that its optimum reaction temperature was 30 ℃,and the optimum reaction pH and pH stable interval were 8.0 and 7.0 to 8.0,respectively.The optimal buffer system for CdnC was determined to be 50 mmol/L Tris-HCl+50 mmol/L NaCl(pH 8.0).The soluble expression of N7-demethylase was successfully achieved,and the function of CdnC in caffeine degradation was determined.关键词
咖啡因/甲基黄嘌呤N7-脱甲基酶/咖啡因降解菌/单倍体蛋白Key words
caffeine degradation/methylxanthine N7-demethylase/Paraburkholderia caffeinilytica/monomer protein分类
生物学引用本文复制引用
李双岐,燕云,高子晴..甲基黄嘌呤N7-脱甲基酶CdnC的可溶性表达及其酶学性质[J].大连工业大学学报,2025,44(2):103-108,6.基金项目
辽宁省民族药功效成分开发与应用重点实验室开放课题(2021JH13/10200038). （2021JH13/10200038）
