麻疯树核糖体失活蛋白Curcin和Curcin C的RNA N-糖苷酶活性研究  

Study on RNA N-glycosidase activity of ribosome inactivating proteins Curcin and Curcin C of Jatropha curcas

作　　者：马芮 彭婕 徐莺[1] MA Rui;PENG Jie;XU Ying(Key Laboratory of Bio-Resources and Eco-Environment Ministry of Education,College of Life Sciences,Sichuan University,Chengdu 610065,China)

机构地区：[1]四川大学生命科学学院生物资源与生态环境教育部重点实验室,成都610065

出　　处：《四川大学学报（自然科学版）》2024年第5期223-229,共7页Journal of Sichuan University(Natural Science Edition)

基　　金：国家自然科学基金(31870315)。

摘　　要：为探究麻疯树核糖体失活蛋白的RNA N-糖苷酶活性,本研究建立了UPLC-MS/MS方法测定麻疯树核糖体失活蛋白Curcin、Curcin C的体外RNA N-糖苷酶脱嘌呤活性.通过单因素实验得到Curcin与RNA32脱嘌呤反应时,反应的最适条件为37℃、pH=4.2、反应时间为4 h.当Curcin C与RNA32脱嘌呤反应时,反应的最适条件为37℃、pH=3.7、反应时间为8 h.Curcin的K_(m)值为8.231μmol/L,Curcin C的K_(m)值为3.302μmol/L,说明Curcin C与底物的亲和力更大.部分金属离子对CurcinC的酶活性具有促进作用,而对Curcin而言均产生了抑制.腺苷浓度达到250μmol/L时,Curcin C酶活性升高,而对于Curcin没有影响.当酶促反应底物为RNA14和RNA32时,Curcin C蛋白的RNA N-糖苷酶活性都显著高于Curcin,表明Curcin C相较于Curcin更具有抗肿瘤药物开发潜力.To investigate the RNA N-glycosidase activity of ribosome inactivating proteins in Jatropha curcas,the UPLC-MS/MS method was established to determine the in vitro RNA N-glycosidase depurination activity of Jatropha ribosomal inactivating proteins Curcin and Curcin C.The optimal conditions for the reaction of Curcin with RNA32 were 37℃,pH=4.2,and 4 h.For Curcin C reacted with RNA32,the optimal conditions were 37℃,pH=3.7 and 8 h.The K_(m) values of Curcin was 8.231μmol/L,while that of Curcin C was 3.302μmol/L,indicating a high affinity of Curcin for the substrate.Some of the metal ions had a promotive effect on the enzymatic activity of Curcin C,while all produced inhibition in the case of Curcin.When the adenosine concentration reached 250μmol/L,the enzyme activity of Curcin C increased,whereas it had no effect on Curcin.When the enzymatic reaction substrates were RNA14 and RNA32,the RNA Nglycosidase activity of Curcin C protein was significantly higher than that of Curcin,indicating that Curcin C has more potential for antitumor drug development compared to Curcin.

关 键 词：核糖体失活蛋白 CURCIN Curcin C RNA N-糖苷酶活性 UPLC-MS 

分 类 号：Q556.2[生物学—生物化学]