Departamento de Biofísica e Farmacologia, Instituto de Biociências, UNESP - Universidade Estadual Paulista, Botucatu, SP, Brazil.
Graduate Program in Tropical Diseases, Faculdade de Medicina de Botucatu (FMB) and Centro de Estudos de Venenos e Animais Peçonhentos (CEVAP), UNESP - Universidade Estadual Paulista, Botucatu, SP, Brazil.
Biochimie. 2020 Dec;179:54-64. doi: 10.1016/j.biochi.2020.09.001. Epub 2020 Sep 16.
Snakebite envenoming is still a worrying health problem in countries under development, being recognized as a neglected disease by the World Health Organization. In Latin America, snakes from the genus Bothrops are widely spread and in Brazil, the Bothrops moojeni is a medically important species. The pharmacological effects of bothropic snake venoms include pain, blisters, bleeding, necrosis and even amputation of the affected limb. Snake venom metalloproteinases are enzymes abundantly present in venom from Bothrops snakes. These enzymes can cause hemorrhagic effects and lead to myonecrosis due to ischemia. Here, we present BmooMP-I, a new P-I class of metalloproteinase (this class only has the catalytic domain in the mature form) isolated from B. moojeni venom. This protein is able to express fibrinogenolytic and gelatinase activities, which play important roles in the prey's immobilization and digestion, and also induces weak hemorrhagic effect. The primary sequence assignment was done by a novel method, SEQUENCE SLIDER, which combines crystallographic, bioinformatics and mass spectrometry data. The high-resolution crystal structure reveals the monomeric assembly and the conserved metal binding site HExxHxxGxxH with the natural substitution Gly148Asp that does not interfere in the zinc coordination. The presence of a structural calcium ion on the surface of the protein, which can play an important role in the stabilization of hemorrhagic toxins, was observed in the BmooMP-I structure. Due to the relevant local and systemic effects of snake venom metalloproteinases, studies involving these proteins help to better understand the pathological effects of snakebite envenoming.
蛇伤中毒仍然是发展中国家令人担忧的健康问题，世界卫生组织已将其确认为被忽视的疾病。在拉丁美洲，矛头蝮属的蛇类广泛分布，而在巴西，莫氏矛头蝮是一种具有重要医学意义的物种。响尾蛇毒液的药理学作用包括疼痛、水疱、出血、坏死，甚至受影响肢体的截肢。蛇毒金属蛋白酶是广泛存在于矛头蛇毒液中的酶。这些酶可引起出血作用，并因缺血导致肌坏死。在这里，我们介绍了 BmooMP-I，这是一种从 B. moojeni 毒液中分离出的新型 P-I 类金属蛋白酶（该类只有成熟形式的催化结构域）。这种蛋白质能够表达纤维蛋白原酶和明胶酶活性，在猎物的固定和消化中起着重要作用，并且还能引起轻微的出血作用。一级序列的分配是通过一种新的方法完成的，即 SEQUENCE SLIDER，它结合了晶体学、生物信息学和质谱数据。高分辨率晶体结构揭示了单体组装和保守的金属结合位点 HExxHxxGxxH，其中天然取代基 Gly148Asp 不干扰锌配位。在 BmooMP-I 结构中观察到表面存在结构钙，这在稳定出血毒素中可能起着重要作用。由于蛇毒金属蛋白酶具有相关的局部和全身作用，涉及这些蛋白质的研究有助于更好地理解蛇伤中毒的病理作用。
