Universidade Federal Rural de Pernambuco, Departamento de Morfologia e Fisiologia Animal, Rua Dom Manoel de Medeiros, s/n, Dois Irmãos, 52171-900 Recife, PE, Brazil.
Department of Medical Engineering, Morsani College of Medicine, University of South Florida, 12901 Bruce B. Downs Blvd 33612, Tampa, Florida, USA.
An Acad Bras Cienc. 2024 Sep 13;96(suppl 1):e20230616. doi: 10.1590/0001-3765202420230616. eCollection 2024.
Cardiovascular diseases, resulting from the deposition of clots in blood vessels, are the leading cause of death worldwide. Fibrinolytic enzymatic activity can catalyze blood clot degradation. Findings show that 36 fungal isolates recovered from Caatinga soils have the potential to produce fibrinolytic protease under submerged conditions. About 58 % of the isolates displayed fibrinolytic activity above 100 U/mL, with Mucor subtilissimus UCP 1262 being the most active. The protease was biochemically and biophysically characterized, showing that the enzyme had a high affinity for SAApNA substrate and was significantly inhibited by fluoride methyl phenyl sulfonyl-C7H7FO2S, suggesting that it is a chymotrypsin-like serine protease. The highest enzyme activity was detected at pH 5.0 and 28 °C. This fibrinolytic protease's far-UV circular dichroism (CD) showed that its secondary structure was primarily α-helical. The purified fibrinolytic enzyme may represent a novel therapeutic agent for treating thrombosis. At temperatures above 65 °C, the enzyme lost all its secondary structure. Its melting temperature was 58.1 °C, the denaturation enthalpy 85.1 kcal/mol, and the denaturation entropy 0.26 kcal/K∙mol.
心血管疾病是由血管中血栓的沉积引起的，是全球死亡的主要原因。纤维蛋白溶解酶活性可以催化血凝块的降解。研究发现，从卡廷加土壤中回收的 36 种真菌分离物在浸没条件下具有产生纤维蛋白溶解蛋白酶的潜力。约 58%的分离物显示出超过 100 U/mL 的纤维蛋白溶解活性，其中粘帚霉 UCP 1262 的活性最高。对蛋白酶进行了生化和生物物理特性分析，表明该酶对 SAApNA 底物具有高亲和力，并且被氟甲基苯基磺酰基-C7H7FO2S 显著抑制，表明它是一种糜蛋白酶样丝氨酸蛋白酶。在 pH 5.0 和 28°C 时检测到最高的酶活性。这种纤维蛋白溶解酶的远紫外圆二色性 (CD) 表明其二级结构主要是α-螺旋。纯化的纤维蛋白溶解酶可能代表一种治疗血栓形成的新型治疗剂。在 65°C 以上的温度下，该酶失去了所有的二级结构。其熔点为 58.1°C，变性焓为 85.1 千卡/摩尔，变性熵为 0.26 千卡/K·摩尔。
