Zhang Pent, Nicholson Diarmuid E, Bujnicki Janusz M, Su Xinzhuan, Brendle James J, Ferdig Michael, Kyle Dennis E, Milhous Wilbur K, Chiang Peter K
Walter Reed Army Institute of Research, Silver Spring, MD 20910-7500, USA.
J Biomed Sci. 2002 Jan-Feb;9(1):34-40. doi: 10.1007/BF02256576.
Methionine aminopeptidase 2 (MetAP2) is responsible for the hydrolysis of the initiator methionine molecule from the majority of newly synthesized proteins. We have cloned the MetAP2 gene from the malaria parasite Plasmodium falciparum (PfMetAP2; GenBank accession number AF348320). The cloned PfMetAP2 has no intron, consists of 1,544 bp and encodes a protein of 354 amino acids with a molecular mass of 40,537 D and an overall base composition of 72.54% A + T. PfMetAP2 has 40% sequence identity with human MetAP2 and 45% identity with yeast MetAP2, and is located in chromosome 14 of P. falciparum. The three-dimensional structure of Pf MetAP2 has been modeled based on the crystal structure of human MetAP2, and several amino acid side chains protruding into the binding pocket that differ between the plasmodial and human enzyme have been identified. The specific MetAP2 inhibitors, fumagillin and TNP-470, potently blocked in vitro growth of P. falciparum and Leishmania donavani, with IC(50) values similar to the prototype drugs. Furthermore, in the case of P. falciparum, the chloroquine-resistant strains are equally susceptible to these two compounds.
甲硫氨酸氨肽酶2(MetAP2)负责从大多数新合成的蛋白质中水解起始甲硫氨酸分子。我们已经从疟原虫恶性疟原虫中克隆了MetAP2基因(PfMetAP2;GenBank登录号AF348320)。克隆的PfMetAP2没有内含子,由1544个碱基对组成,编码一个354个氨基酸的蛋白质,分子量为40537道尔顿,总体碱基组成中A+T占72.54%。PfMetAP2与人类MetAP2的序列同一性为40%,与酵母MetAP2的同一性为45%,位于恶性疟原虫的14号染色体上。PfMetAP2的三维结构已基于人类MetAP2的晶体结构进行建模,并且已鉴定出一些伸入结合口袋的氨基酸侧链,这些侧链在疟原虫和人类酶之间存在差异。特定的MetAP2抑制剂烟曲霉素和TNP-470可有效阻断恶性疟原虫和杜氏利什曼原虫的体外生长,其IC50值与原型药物相似。此外,对于恶性疟原虫,耐氯喹菌株对这两种化合物同样敏感。