Delgado, Josué and Owens, Rebecca A. and Doyle, Sean and Núñez, Felix and Asensio, Miguel A. (2017) Quantitative proteomics reveals new insights into calcium-mediated resistance mechanisms in Aspergillus flavus against the antifungal protein PgAFP in cheese. Food Microbiology, 66. pp. 1-10. ISSN 1095-9998

Preview

Download (3MB) | Preview

Abstract

The ability of Aspergillus flavus to produce aflatoxins in dairy products presents a potential hazard. The antifungal protein PgAFP from Penicillium chrysogenum inhibits various foodborne toxigenic fungi, including Aspergillus flavus. However, PgAFP did not inhibit A. flavus growth in cheese, which was related to the associated cation content. CaCl2 increased A. flavus permeability and prevented PgAFP-mediated inhibition in potato dextrose broth (PDB). PgAFP did not elicit any additional increase in permeability of CaCl2-incubated A. flavus. Furthermore, PgAFP did not alter metabolic capability, chitin deposition, or hyphal viability of A. flavus grown with CaCl2. Comparative proteomic analysis after PgAFP treatment of A. flavus in calcium-enriched PDB revealed increased abundance of 125 proteins, including oxidative stress-related proteins, as determined by label-free mass spectrometry (MS)-based proteomics. Seventy proteins were found at lower abundance, with most involved in metabolic pathways and biosynthesis of secondary metabolites. These changes do not support the blockage of potential PgAFP receptors in A. flavus by calcium as the main cause of the protective role. A. flavus resistance appears to be mediated by calcineurin, G-protein, and γ-glutamyltranspeptidase that combat oxidative stress and impede apoptosis. These findings could serve to design strategies to improve PgAFP activity against aflatoxigenic moulds in dairy products.

Item Type:	Article
Keywords:	Antifungal protein; Cheese; Proteomics; Calcium; Calcineurin;
Academic Unit:	Faculty of Science and Engineering > Biology
Item ID:	10914
Identification Number:	https://doi.org/10.1016/j.fm.2017.03.015
Depositing User:	Rebecca Owens
Date Deposited:	02 Jul 2019 15:43
Journal or Publication Title:	Food Microbiology
Publisher:	Elsevier
Refereed:	Yes
URI:	https://www.sciencedirect.com
Use Licence:	This item is available under a Creative Commons Attribution Non Commercial Share Alike Licence (CC BY-NC-SA). Details of this licence are available here

Repository Staff Only(login required)

Item control page

Downloads

Origin of downloads