Deciphering the relationships among enzymatic systems and virulence of beauveria bassiana: A review

Abstract

Intensive crop production and extensive use of harmful synthetic chemical pesticides create numerous socio-economic problems worldwide. Therefore, sustainable solutions are needed for insect pest control, such as biological control agents. The fungal insect pathogen Beauveria bassiana has shown considerable potential as a biological control agent against a broad range of insects. The insight into the virulence mechanism of B. bassiana is essential to show the robustness of its use. B. bassiana has several determinants of virulence, including the production of cuticle-degrading enzymes (CDEs), such as proteases, chitinases, and lipases. CDEs are essential in the infection process as they hydrolyze the significant components of the insect's cuticle. Moreover, B. bassiana has evolved effective antioxidant mechanisms that include enzyme families that act as reactive oxygen species (ROS) scavengers, e.g., superoxide dismutases, catalases, peroxidases, and thioredoxins. In B. bassiana, the number of CDEs and antioxidant enzymes are characterized in recent years. These enzymes are believed to be crucial player of evolutionary process in this organism and their role in various mechanism of biological control. Recent discoveries have significantly increased our potential understanding on several potentially wanted unknown mechanisms of B. bassiana infection. This review focuses on the progress detailed in the studies of these enzymes and provides an overview of enzymatic activities and their contributions to virulence.