A class I hydrophobin inTrichoderma virensinfluences plant-microbe interactions through enhancement of enzyme activity and MAMP recognition

Abstract

The filamentous fungus, Trichoderma virens, is a well-known mycoparasitic plant symbiont, valued for its biocontrol capabilities. T. virens initiates a symbiotic relationship with a plant host through the colonization of its roots. To achieve colonization, the fungus must communicate with the host and evade its innate defenses. Hydrophobins from Trichoderma spp. have previously been demonstrated to be involved in colonization of host roots. In this study, the class I hydrophobin, HFB9A from T. virens was characterized for a potential role in root colonization. Δhfb9a gene deletion mutants colonized less than the wild-type strain, were unable to induce systemic resistance against Colletotrichum graminicola, and showed a reduction in the activity of its cell wall degrading enzymes. The purified HFB9A protein was able to complement the enzyme activity of mutant culture filtrates as well as enhance the activity of commercially sourced cellulase. When exogenously applied to Arabidopsis plants, HFB9A protein induced phosphorylation of AtMAPK3/6, suggesting that it functions as a microbe-associated molecular pattern.

Trichoderma asperellum empowers tomato plants and suppresses Fusarium oxysporum through priming responses

“…Mycoparasitism is the most efficient antifungal mechanism of Trichoderma spp. (e.g., T. virens , T. harzianum ) via recognizing the pathogen and growing alongside the pathogen hyphae, then dissolution and death of the pathogen ( Benítez et al, 2004 ; Sharon et al, 2007 ; Hewedy et al, 2020a , b ; Contreras-Cornejo et al, 2021 ; Taylor et al, 2021 ; Mukherjee et al, 2022 ). Various factors such as native environmental habitats, strains, pathogen species, and laboratory findings for testing their antifungal activities affect the Trichoderma biocontrol machinery.…”