Impairment of the cellulose degradation machinery enhances Fusarium oxysporum virulence but limits its reproductive fitness.

Abstract

Fungal pathogens grow in the apoplastic space, in constant contact with the plant cell wall (CW) that hinders microbe progression while representing a source of nutrients. Although numerous fungal CW modifying proteins have been identified, their role during host colonization remains underexplored. Here, we show that the root-infecting plant pathogen Fusarium oxysporum (Fo) does not require its complete arsenal of cellulases to infect the host plant. Quite the opposite: Fo mutants impaired in cellulose degradation become hypervirulent by enhancing the secretion of virulence factors. On the other hand, the reduction in cellulase activity had a severe negative effect on saprophytic growth and microconidia production during the final stages of the Fo infection cycle. These findings enhance our understanding of the function of plant CW degradation on the outcome of host-microbe interactions and reveal an unexpected role of cellulose degradation in a pathogen's reproductive success.

• Authors: Francisco M Gámez-Arjona, Stefania Vitale, Aline Voxeur, Susanne Dora, Sascha Müller, Gloria Sancho-Andrés, Juan Carlos Montesinos, Antonio Di Pietro, Clara Sánchez-Rodríguez
• Journal: Science advances (Sci Adv) Vol. 8 Issue 16 Pg. eabl9734 (04 22 2022) ISSN: 2375-2548 [Electronic] United States
• PMID: 35442735 (Publication Type: Journal Article)

Chemical References

• Fungal Proteins
• Cellulose

Topics

• Cellulose
• Fungal Proteins
• Fusarium
• Genetic Fitness
• Plant Diseases (microbiology)
• Virulence