Chen Xiaochun, Xie Suji, Bhat Shridhar, Kumar Nirbhay, Shapiro Theresa A, Liu Jun O
Department of Pharmacology and Molecular Sciences, Johns Hopkins School of Medicine, 725 North Wolfe Street, Baltimore, MD 21205, USA.
Chem Biol. 2009 Feb 27;16(2):193-202. doi: 10.1016/j.chembiol.2009.01.006.
The fumagillin family of natural products is known to inhibit angiogenesis through irreversible inhibition of human type 2 methionine aminopeptidase (MetAP2). Recently, fumagillin and TNP-470 were reported to possess antimalarial activity in vitro, and it was hypothesized that this inhibition was mediated by interaction with the putative malarial ortholog of human MetAP2. In this report, we have overexpressed and purified to near-homogeneity PfMetAP2 from bacteria, yeast, and insect cells. Although none of the recombinant forms of PfMetAP2 exhibited enzymatic activity in existing assays, PfMetAP2 proteins expressed in both yeast and insect cells were able to bind to fumagillin in a pull-down assay. The interaction between fumagillin and analogs with PfMetAP2 was further demonstrated using a newly established mammalian three-hybrid assay incorporating a conjugate between dexamethasone and fumagillin. Unlike human (Hs)MetAP2, it was found that PfMetAP2 is bound to fumagillin noncovalently. Importantly, a new analog of fumagillin, fumarranol, was demonstrated to interact with PfMetAP2 and inhibit the growth of both chloroquine-sensitive and drug-resistant Plasmodium falciparum strains in vitro. Antiparasite activity of fumagillin and fumarranol was also demonstrated in vivo using a mouse malaria model. These findings suggest that PfMetAP2 is a viable target, and fumarranol is a promising lead compound for the development of novel antimalarial agents.
已知天然产物烟曲霉素家族通过不可逆地抑制人2型甲硫氨酸氨肽酶（MetAP2）来抑制血管生成。最近，有报道称烟曲霉素和TNP - 470在体外具有抗疟活性，据推测这种抑制作用是通过与人类MetAP2的假定疟疾同源物相互作用介导的。在本报告中，我们已从细菌、酵母和昆虫细胞中过表达并纯化出近乎均一的恶性疟原虫MetAP2（PfMetAP2）。尽管在现有检测中PfMetAP2的重组形式均未表现出酶活性，但在酵母和昆虫细胞中表达的PfMetAP2蛋白在下拉实验中能够与烟曲霉素结合。使用新建立的包含地塞米松与烟曲霉素共轭物的哺乳动物三杂交实验，进一步证明了烟曲霉素及其类似物与PfMetAP2之间的相互作用。与人类（Hs）MetAP2不同，发现PfMetAP2与烟曲霉素是非共价结合的。重要的是，已证明烟曲霉素的一种新类似物富马雷醇可与PfMetAP2相互作用，并在体外抑制氯喹敏感和耐药恶性疟原虫菌株的生长。在小鼠疟疾模型中也证明了烟曲霉素和富马雷醇的抗寄生虫活性。这些发现表明PfMetAP2是一个可行的靶点，富马雷醇是开发新型抗疟药物的有前景的先导化合物。
