Abstract：
CsPT4 is an aromatic prenyltransferase that synthesizes cannabigerolic acid (CBGA), the key intermediate of cannabinoid biosynthesis in Cannabis sativa, from olivetolic acid (OA) and geranyl diphosphate (GPP). CsPT4 has a catalytic potential to produce a variety of CBGA analogs via regioselective C-prenylation of aromatic substrates having resorcylic acid skeletons including bibenzyl 2,4-dihydroxy-6-phenylethylbenzoic acid (DPA). In this study, we further investigated the substrate specificity of CsPT4 using phlorocaprophenone (PCP) and 2\',4\',6\'-trihydroxydihydrochalcone (THDC), the isomers of OA and DPA, respectively, and demonstrated that CsPT4 catalyzed both C-prenylation and O-prenylation reactions on PCP and THDC that share acylphloroglucinol substructures. Interestingly, the kinetic parameters of CsPT4 for these substrates differed depending on whether they underwent C-prenylation or O-prenylation, suggesting that this enzyme utilized different substrate-binding modes suitable for the respective reactions. Aromatic prenyltransferases that catalyze O-prenylation are rare in the plant kingdom, and CsPT4 was notable for altering the reaction specificity between C- and O-prenylations depending on the skeletons of aromatic substrates. We also demonstrated that enzymatically synthesized geranylated acylphloroglucinols had potent antiausterity activity against PANC-1 human pancreatic cancer cells, with 4\'-O-geranyl THDC being the most effective. We suggest that CsPT4 is a valuable catalyst to generate biologically active C- and O-prenylated molecules that could be anticancer lead compounds.
摘要：
CsPT4是一种合成大麻酚酸（CBGA）的芳香族异戊烯基转移酶，大麻中大麻素生物合成的关键中间体，来自橄榄酸（OA）和香叶基二磷酸（3GPP）。CsPT4具有催化潜力,通过具有间苯二酸骨架的芳族底物的区域选择性C-异戊二烯化产生多种CBGA类似物,所述间苯二酸骨架包括二苄基2,4-二羟基-6-苯基乙基苯甲酸(DPA)。在这项研究中,我们进一步研究了使用苯丙苯酮（PCP）和2'的CsPT4的底物特异性，4\',6\'-三羟基二氢查耳酮（THDC），OA和DPA的异构体，分别,并证明CsPT4在共享酰基间苯三酚亚结构的PCP和THDC上同时催化C-戊烯化和O-戊烯化反应。有趣的是,这些底物的CsPT4的动力学参数取决于它们是否经历了C-戊烯化或O-戊烯化，这表明该酶利用了适用于各个反应的不同底物结合模式。催化O-戊烯化的芳香异戊烯基转移酶在植物界中很少见，CsPT4在改变C-和O-异戊二烯化之间的反应特异性方面是值得注意的，这取决于芳香族底物的骨架。我们还证明了酶促合成的香叶酰化的酰基间苯三酚对PANC-1人胰腺癌细胞具有有效的抗紧缩活性，4'-O-香叶基THDC是最有效的。我们建议CsPT4是产生可能是抗癌先导化合物的生物活性C-和O-异戊二烯化分子的有价值的催化剂。
