Abstract
Camptothecin is a complex monoterpenoid indole alkaloid with remarkable antitumor activity.Given that two C-10 modified camptothecin derivatives,topotecan and irinotecan,have been approved as potent anticancer agents,there is a critical need for methods to access other aromatic ring-functionalized congeners(e.g.,C-9,C-10,etc.).However,contemporary methods for chemical oxi-dation are generally harsh and low-yielding when applied to the camptothecin scaffold,thereby lim-iting the development of modified derivatives.Re-ported herein,we have identified four tailoring enzymes responsible for C-9 modifications of camptothecin from Nothapodytes tomentosa,via metabolomic and transcriptomic analysis.These consist of a cytochrome P450(NtCPT9H)which catalyzes the regioselective oxidation of campto-thecin to 9-hydroxycamptothecin,as well as two methyltransferases(NtOMT1/2,converting 9-hydroxycamptothecin to 9-methoxycamptothecin),and a uridine diphosphate-glycosyltransferase(NtUGT5,decorating 9-hydroxycamptothecin to 9-β-D-glucosyloxycamptothecin).Importantly,the critical residues that contribute to the specific cat-alytic activity of NtCPT9H have been elucidated through molecular docking and mutagenesis ex-periments.This work provides a genetic basis for producing camptothecin derivatives through meta-bolic engineering.This will hasten the discovery of novel C-9 modified camptothecin derivatives,with profound implications for pharmaceutical manufacture.
基金项目
National Natural Science Foundation of China(82225043)
Biological Resources Program(KFJ-BRP-009)
Yunnan Revitalization Talent Support Program"Yunling Scholar"Project(S.-X.H.)()
Yunnan Revitalization Talent Support Program"Young Talent"Project(J.-P.H.)()
NETL
NSTL
万方数据