Proteomic analysis of the inhibitory effect of oligochitosan on the fungal pathogen, Botrytis cinerea.

BACKGROUND: The fungal pathogen, Botrytis cinerea, infects a broad range of horticultural plants worldwide, resulting in significant economic losses. A derivative of chitosan, oligochitosan, has been reported to be an eco-friendly alternative to synthetic fungicides.

RESULTS: Oligochitosan can greatly inhibit B. cinerea spore germination and induce protein carbonylation. To further investigate the molecular mechanism underlying the inhibitory effect, a comparative proteome analysis was conducted of oligochitosan-treated vs. non-treated B. cinerea spores. The cellular proteins were obtained from B. cinerea spore samples and subjected to two-dimensional gel electrophoresis. A total of 21 differentially expressed proteins (DEPs) were identified. Three DEPs were up-regulated in the oligochitosan-treated vs. the untreated spores; including scytalone dehydratase and a serine carboxypeptidase III precursor. In contrast, 7 DEPs, including Hsp 88 and cell division cycle protein 48, were down-regulated by the oligochitosan treatment. Notably, 10 DEPs, including phosphatidylserine decarboxylase proenzyme and ATP-dependent molecular chaperone HSC82, were only detected in the control spores; while 1 DEP, a non-annotated, predicted protein, was only detected in the oligochitosan-treated spores.

CONCLUSION: Oligochitosan may affect the spore germination of B. cinerea by impairing the protein function. These findings have practical implications for the use of oligochitosan to control fungal pathogens. This article is protected by copyright. All rights reserved.