Investigating the Role of Copper Radical Oxidases in Verticillium Pathogenesis

Phytopathogenic fungi secrete diverse enzymes to help them infect host plants. Foliar phytopathogens like Colletotrichum species, contain tandem copper radical oxidase (CRO) and peroxidase genes. The CRO-peroxidase pair is co-secreted during initial leaf penetration phases. The CRO oxidizes long-chain alcohols found in the leaf cuticle while the peroxidase activates the CRO. We discovered that the vascular wilt causing Verticillium fungi, which infect host roots also contained adjacent genes encoding a CRO and catalase/peroxidase. Surprisingly, in vitro tests of Verticillium CROs revealed poor activity on long-chain alcohols and instead displayed activity on aryl alcohols and galactose-containing carbohydrates, reminiscent of plant cell wall components. This project will investigate the roles CROs and peroxidases play in V. dahliae growth, development and virulence through gene knockout studies and tomato infection assays. Natural substrates oxidised by Verticillium CROs will also be identified through mass spectrometry analysis of plant extracts. Novel data generated by this project could further our understanding of verticillium pathogen-host interactions and become applicable toward the development of biochemical means for combatting verticillium wilts. Through this project, participating institutions will benefit through the strengthening of ties to further promote collaboration and the development of future projects through the sharing of knowledge.

Faculty Supervisor:

Harry Brumer

Student:

Partner:

The University of Göttingen

Discipline:

Life Sciences

Sector:

Agriculture and Food; Biotechnology

University:

The University of British Columbia

Program: