Sunday, April 29, 2007

Proteomic analysis of softwood-degrading fungi towards biomimetic enzyme applications

Sonam Mahajan and Emma R. Master. Department of Chemical Engineering and Applied Chemistry, University of Toronto, 200 College Street, WB 319, Toronto, ON M5S 3E5, Canada


Advances in science and technology are developing new ways to revitalize forest industries and address consumer demands for biodegradable materials and cleaner fuels. Biocatalysts are important tools for harnessing the potential of wood fibres since they can perform highly specific reactions with low environmental impact. Challenges to bioconversion technologies as applied to wood fibres include accessibility of plant cell wall polymers and stability of the biocatalysts used. Moreover, differences in the molecular structure and distribution of plant cell wall polymers in different plant species and tissues impact bioprocess efficiency. This project describes proteomic analysis of enzymes secreted by the white-rot basidiomycete Phanerochaete carnosa, and the brown-rot basidiomycete Postia placenta, while transforming lignocellulosic substrates. Proteins will be extracted from fungal cultivations and separated by gel electrophoresis.  Protein bands will be cut and prepared for in-gel trypsin digestion, and then characterized by MALDI-ToF/ToF. The publicly available genome sequence of P.chrysosporium will be used to facilitate the identification of proteins secreted by P.carnosa, while sequencing of the P. placenta genome is currently underway and will be an important resource for protein analysis in this study. It is anticipated that this project will identify profiles of expressed microbial enzymes that are specific to transformation of particular lignocellulosic fibres.  This will enable tailored applications of enzymes for processing wood fibres in the future. In addition, the comparison of proteins secreted by P. carnosa and P. placenta will also provide further insight into the unique biotransformation strategies that have evolved in brown-rot and white-rot fungi.