Development of Modular, Self-Assembling Synthetic Protein Complexes As Screening Platforms for Enhanced Enzyme Discovery

At the forefront of enzyme discovery, Novozymes continues to search for better ways to screen a growing diversity of glycosyl hydrolases in order to improve enzyme cocktails for second-generation biofuel production.  To this end, we have successfully integrated a synthetic biology approach into our next generation of enzyme discovery platforms.  Specifically, we have leveraged the available natural diversity of cellulosomal components to develop an artificial mini-cellulosome as the basis for a versatile cell-free method to screen combinations of multiple enzyme activities.  In the process, we have engineered a highly thermostable scaffoldin comprised of distinct cohesin domains that stably bind cognate dockerins with high specificity for extended periods under lignocellulose hydrolysis conditions.  These protein-protein interactions serve as respective binding modules for covalently-linked libraries of different enzyme classes.  Our synthetic cellulosome approach has been adapted to an automated HTS system through which enzymes of synergistic quality are more efficiently identified compared to past conventional approaches.  Finally, we have successfully employed this novel screening platform to discover promising new enzyme candidates tailored for improved hydrolytic performance on AFEX-PCS, an industrially-relevant biomass substrate.