Dib Heloisa Xavier, de Oliveira Daniella Gorete Lourenço, de Oliveira Caio Fernando Ramalho, Taveira Gabriel Bonan, de Oliveira Mello Erica, Verbisk Newton Valério, Chang Marilene Rodrigues, Corrêa Junior Dario, Gomes Valdirene Moreira, Macedo Maria Lígia Rodrigues
Laboratório de Purificação de Proteínas e suas Funções Biológicas, Faculdade de Ciências de Alimentos e Nutrição, Universidade Federal do Mato Grosso do Sul, Campo Grande, MS, 79070-900, Brazil.
Laboratório de Fisiologia e Bioquímica de Microrganismos, Universidade Estadual do Norte Fluminense, Campos dos Goytacazes, RJ, 28013-600, Brazil.
Arch Microbiol. 2019 Mar;201(2):223-233. doi: 10.1007/s00203-018-1598-8. Epub 2018 Nov 27.
We describe the characterization of IETI, the first trypsin inhibitor purified from Inga edulis, a tree widely distributed in Brazil. Two-step chromatography was used to purify IETI, a protein composed of a single peptide chain of 19,685.10 Da. Amino-terminal sequencing revealed that IETI shows homology with the Kunitz family, as substantiated by its physical-chemical features, such as its thermal (up to 70 °C) and wide-range pH stability (from 2 to 10), and the value of its dissociation constant (6.2 nM). IETI contains a single reactive site for trypsin, maintained by a disulfide bridge; in the presence of DTT, its inhibitory activity was reduced in a time- and concentration-dependent manner. IETI presented activity against Candida ssp., including C. buinensis and C. tropicalis. IETI inhibitory activity triggered yeast membrane permeability, affecting cell viability, thus providing support for the use of IETI in further studies for the control of fungal infections.
我们描述了IETI的特性，它是从广泛分布于巴西的一种树木——可食印加树中纯化得到的首个胰蛋白酶抑制剂。采用两步色谱法纯化IETI，它是一种由19,685.10 Da的单肽链组成的蛋白质。氨基末端测序显示IETI与库尼茨家族具有同源性，这一点由其物理化学特性证实，如热稳定性（高达70°C）和宽范围pH稳定性（2至10）以及其解离常数的值（6.2 nM）。IETI含有一个由二硫键维持的针对胰蛋白酶的单一活性位点；在二硫苏糖醇（DTT）存在的情况下，其抑制活性以时间和浓度依赖的方式降低。IETI对包括布氏假丝酵母和热带假丝酵母在内的念珠菌属具有活性。IETI的抑制活性引发酵母细胞膜通透性，影响细胞活力，从而为在进一步研究中使用IETI控制真菌感染提供了支持。
Zotero 插件