1. Biochemical characterization of a Kunitz inhibitor from Inga edulis seeds with antifungal activity against Candida spp.
- Author
-
Dib HX, de Oliveira DGL, de Oliveira CFR, Taveira GB, de Oliveira Mello E, Verbisk NV, Chang MR, Corrêa Junior D, Gomes VM, and Macedo MLR
- Subjects
- Amino Acid Sequence, Antifungal Agents isolation & purification, Antifungal Agents pharmacology, Brazil, Plant Proteins isolation & purification, Plant Proteins pharmacology, Seeds chemistry, Trypsin Inhibitors isolation & purification, Trypsin Inhibitors pharmacology, Antifungal Agents chemistry, Candida drug effects, Fabaceae chemistry, Plant Proteins chemistry, Trypsin Inhibitors chemistry
- Abstract
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.
- Published
- 2019
- Full Text
- View/download PDF