Faheem Muhammad, Fonseca Valadares Napoleão, Brandão-Neto José, Bellini Dom, Collins Patrick, Pearce Nicholas M, Bird Louise, Roberta Torini Juliana, Owens Raymond, DMuniz Pereira Humberto, Von Delft Frank, Barbosa João Alexandre Ribeiro Gonçalves
Laboratório de Biofísica Molecular, Departamento de Biologia Celular, Universidade de Brasília, Brasília, DF 70910-900, Brazil.
Programa de Pós-Graduação em Ciências Genômicas e Biotecnologia, Universidade Católica de Brasília, SGAN 916 Módulo B Avenida W5 - Asa Norte, Brasília, DF, Brazil.
Biochem J. 2021 Oct 15;478(19):3655-3670. doi: 10.1042/BCJ20210041.
Several Schistosoma species cause Schistosomiasis, an endemic disease in 78 countries that is ranked second amongst the parasitic diseases in terms of its socioeconomic impact and human health importance. The drug recommended for treatment by the WHO is praziquantel (PZQ), but there are concerns associated with PZQ, such as the lack of information about its exact mechanism of action, its high price, its effectiveness - which is limited to the parasite's adult form - and reports of resistance. The parasites lack the de novo purine pathway, rendering them dependent on the purine salvage pathway or host purine bases for nucleotide synthesis. Thus, the Schistosoma purine salvage pathway is an attractive target for the development of necessary and selective new drugs. In this study, the purine nucleotide phosphorylase II (PNP2), a new isoform of PNP1, was submitted to a high-throughput fragment-based hit discovery using a crystallographic screening strategy. PNP2 was crystallized and crystals were soaked with 827 fragments, a subset of the Maybridge 1000 library. X-ray diffraction data was collected and structures were solved. Out of 827-screened fragments we have obtained a total of 19 fragments that show binding to PNP2. Fourteen of these fragments bind to the active site of PNP2, while five were observed in three other sites. Here we present the first fragment screening against PNP2.
几种血吸虫会引发血吸虫病，这是一种在78个国家流行的疾病，就其社会经济影响和对人类健康的重要性而言，在寄生虫病中排名第二。世界卫生组织推荐用于治疗的药物是吡喹酮（PZQ），但人们对吡喹酮存在一些担忧，比如其确切作用机制信息不足、价格高昂、其有效性（仅限于寄生虫的成虫形式）以及耐药性报告。这些寄生虫缺乏从头合成嘌呤的途径，这使得它们在核苷酸合成方面依赖嘌呤补救途径或宿主嘌呤碱基。因此，血吸虫嘌呤补救途径是开发必要且有选择性的新药的一个有吸引力的靶点。在本研究中，嘌呤核苷酸磷酸化酶II（PNP2），一种PNP1的新亚型，采用晶体学筛选策略进行了基于片段的高通量命中发现。PNP2被结晶，晶体用827个片段（Maybridge 1000文库的一个子集）浸泡。收集了X射线衍射数据并解析了结构。在827个筛选片段中，我们总共获得了19个与PNP2显示有结合的片段。其中14个片段与PNP2的活性位点结合，而在其他三个位点观察到5个片段。在此我们展示了首次针对PNP2的片段筛选。
