Biochemistry of Entomopathogens and Mycoparasites: Metarhizium

Pest management in agriculture is facing a tough challenge due to the ineffectiveness of synthetic chemicals. Therefore, eco-friendly alternatives are urgently needed. One of the promising options is the utilization of entomopathogenic fungi (EPF), especially those of the genus Metarhizium. These fungi use two primary mechanisms to target their hosts: (1) mechanical pressure to rupture membranous or slightly sclerotic areas and (2) biochemical degradation of the cuticle, such as proteins, chitin, and lipids, through the use of extracellular hydrolytic enzymes such as proteases, chitinases, and lipases. Metarhizium secretes several enzymes, including metalloproteases, subtilisin (Pr1), trypsin (Pr2), and cysteine proteases (Pr4), during the infection process. Additionally, the chitinase-encoding genes chit1, chi2, and chi3 are activated. This chapter centers on EPF belonging to the genus Metarhizum, their utilization as biocontrollers, their enzymes, and the potential future use of these enzymes as biopesticides.