Enzymatic Aminopropylation of Certain Secondary Amines.
作者:Akira SHIRAHATA、Harumi HOSODA、Norio TAKAHASHI、Takanobu BEPPU、Masaru NIITSU、Keijiro SAMEJIMA
DOI:10.1248/bpb.18.355
日期:——
Two unusual aminopropyl acceptors found in a survey of putrescine binding sites of mammalian spermidine synthase, N-methylputrescine (I) and 4-aminomethylpiperidine (II), were examined for their aminopropyl derivatives. Studies under in vitro incubation conditions suggested that the aminopropyl derivatives of the secondary amine of I and II, N4-methylspermidine (Is) and 1-N-(3-aminopropyl)-4-aminomethylpiperidine (IIs), and of the primary amine of I and II, N8-methylspermidine (Ip) and 4-[N-(3-aminopropyl) aminomethyl] piperidine (IIp), respectively, were biosynthesized by rat spermidine synthase. Studies on the cell culture system of cultured rat hepatoma (HTC) cells treated with α-difluoromethylornithine, an ornithine decarboxylase inhibitor, clearly showed the presence of Is and Ip when I was administered, and IIs and IIp when II was administered, with no detection of putrescine or spermidine. These results suggested that mammalian spermidine synthase can transfer the aminopropyl moiety of decarboxylated S-adenosylmethionine to certain secondary amines in living cells.
在一项关于哺乳动物精胺合成酶中腐胺结合位点的调查中,发现了两个不寻常的氨基丙基受体,N-甲基腐胺(I)和4-氨基甲基哌啶(II),研究了它们的氨基丙基衍生物。在体外孵育条件下进行的研究表明,I和II的二级胺的氨基丙基衍生物,即N4-甲基精胺(Is)和1-N-(3-氨基丙基)-4-氨基甲基哌啶(IIs),以及I和II的一级胺的氨基丙基衍生物,即N8-甲基精胺(Ip)和4-[N-(3-氨基丙基)氨基甲基]哌啶(IIp),分别是通过大鼠精胺合成酶生物合成的。在用α-二氟甲基鸟氨酸(一种鸟氨酸脱羧酶抑制剂)处理的培养大鼠肝癌细胞(HTC细胞)的细胞培养系统中进行的研究清楚地显示,当给药I时存在Is和Ip,当给药II时存在IIs和IIp,未检测到腐胺或精胺。这些结果表明,哺乳动物精胺合成酶能在活细胞中将脱羧化的S-腺苷甲硫氨酸的氨基丙基部分转移到某些二级胺上。