Chagas disease is one of seventeen neglected tropical diseases according to the World Health Organization (WHO). The histidine-glutamate metabolic pathway is an oxidative route that has shown to be relevant for the bioenergetics in Trypanosoma cruzi, the etiological agent for Chagas disease. Histidine ammonia-lyase participates in the first stage of the histidine catabolism, catalyzing the conversion of l-histidine into urocanate. This work presents the three-dimensional (3D) structure of Trypanosoma cruzi histidine ammonia-lyase enzyme (TcHAL) and some comparisons of it to homologous structures. The enzyme was expressed, purified and assayed for crystallization, what allowed the obtainment of crystals of sufficient quality to collect X-ray diffraction data up to 2.55 Å resolution. After refinement, some structural analyses indicated that the structure does not contain the active site protection domain, in opposition to previously known 3D structures from plants and fungi phenylalanine ammonia-lyase, therefore, it is the first structure of eukaryotic ammonia-lyases that lacks this domain.

根据世界卫生组织（WHO），恰加斯病是十七种被忽视的热带病之一。组氨酸-谷氨酸代谢途径是一种氧化途径，已被证明与南美锥虫病的病原体克氏锥虫的生物能有关。组氨酸氨裂合酶参与组氨酸分解代谢的第一阶段，催化1-组氨酸转化为尿烷酸酯。这项工作提出了锥虫锥虫组氨酸氨裂解酶（TC的三维（3D）结构HAL）及其与同源结构的一些比较。表达，纯化和分析该酶的结晶，可以得到足够质量的晶体，以收集高达2.55Å分辨率的X射线衍射数据。精炼后，一些结构分析表明，该结构不包含活性位点保护域，这与植物和真菌苯丙氨酸氨解酶的先前已知3D结构相反，因此，这是真核氨解酶的第一个缺少这种结构的结构。域。