| Congresso Brasileiro de Microbiologia 2023 | Resumo: 530-1 | ||||
Resumo:In recent years, there have been several reports of the presence of toxic proteins in cultivated or wild plant species, which are implicated in plant defense mechanisms. The existence of these proteins raises the possibility of biotechnological applications originating from the development of new techniques to combat diseases caused by fungi. In this context, we have chitin-binding proteins. Chitin is an essential component of the fungal cell wall, so chitin-binding proteins are important in controlling fungal growth. Thus, the objective of this study was to characterize and evaluate the in vitro antimicrobial effect of peptides, with chitin binding properties, isolated from Capsicum annuum seeds, on the growth of Candida albicans. Initially, proteins were extracted in phosphate pH 5.4 and a chitin column was equilibrated with sodium acetate (0.08 M, pH 4.5), where 50 mg of peptide rich heated fraction, was applied. Subsequently, the retained material was eluted with 0.1 M HCl. Tricine SDS-PAGE was used to visualize the peptides. After chromatography, two fractions, F1 (non-retained in chitin column) and F2 (retained in chitin column, named Ca-F2) were obtained. Electrophoresis showed major protein bands between 3 and 14 kDa. Electrophoresis from chitin affinity chromatography showed also major bands between 3 and 14 kDa, especially for Ca-F2 retained in column. One peptide obtained from the Ca-F2 fraction was identified by mass spectrometry and showed similarity to seed 2S albumin, named Ca-Alb2S. Ca-F2 inhibited the growth of C. albicans in different concentrations. It was found that Ca-F2 caused membrane permeabilization, increased ROS and altered mitochondrial function in the yeast C. albicans, at a concentration of 100 μg/mL-1. Ca-F2 were not toxic to mammalian cells and still have a high survival rate when tested in vivo on Galleria mellonella larvae. It is concluded that Ca-F2 showed significant antifungal activity, which indicates great potential for the development of new antifungal molecules. Palavras-chave: antimicrobial activity, 2S albumin, Capsicum, fungi Agência de fomento:UENF, FAPERJ, CAPES, CNPq | |||||