Secretome analysis of the phytopathogen Macrophomina phaseolina cultivated in liquid medium supplemented with and without soybean leaf infusion

Macrophomina phaseolina (Tassi) Goid. is a fungal pathogen that causes root and stem rot in several economically important crops. However, most of disease control strategies have shown limited effec-tiveness. Despite its impact on agriculture, molecular mechanisms involved in the interaction with host plant remains poorly understood. Nevertheless, it has been proven that fungal pathogens secrete a va-riety of proteins and metabolites to successfully infect their host plants. In this study, a proteomic analysis of proteins secreted by M. phaseolina in culture media supplemented with soybean leaf infusion was performed. A total of 250 proteins were identified with a predominance of hydrolytic enzymes. Plant cell wall degrading enzymes together peptidases were found, probably involved in the infection process. Predicted effector proteins were also found that could induce plant cell death or suppress plant immune response. Some of the putative effectors presented similarities to known fungal virulence factors. Expression analysis of ten selected protein-coding genes showed that these genes are induced during host tissue infection and suggested their participation in the infection process. The identification of secreted proteins of M. phaseolina could be used to improve the understanding of the biology and pathogenesis of this fungus. Although leaf infusion was able to induce changes at the proteome level, it is necessary to study the changes induced under conditions that mimic the natural infection process of the soil-borne pathogen M. phaseolina to identify virulence factors.(c) 2023 British Mycological Society. Published by Elsevier Ltd. All rights reserved.

Automated summary

A proteomic analysis of the proteins secreted by M. phaseolina in soybean leaf infusion culture media was conducted. The analysis revealed a large number of hydrolytic enzymes, as well as plant cell wall degrading enzymes and peptidases possibly involved in the infection process. Putative effector proteins that could induce plant cell death or suppress plant immune response, some of which shared similarities with known fungal virulence factors, were also identified. Expression analysis suggested that selected protein-coding genes are induced during host tissue infection and may participate in the infection process. The identification of secreted proteins of M. phaseolina can contribute to understanding the biology and pathogenesis of this fungus, but further studies are needed to investigate the changes induced during the natural infection process.