B25 Ruttan Hall
How substitutions outside the active site create more efficient enzymes
Abstract: Biocatalysis, used in the production of specialty chemicals, pharmaceuticals, and biofuels, relies on efficient enzymes to catalyze chemical transformations. However, current enzyme design struggles to identify substitutions beyond the active site that contribute to catalysis, limiting the development of efficient enzymes for biocatalysis. To identify how distant residues contribute to catalysis, we exchanged the catalytic activity of a hydroxynitrile lyase (HNL) with that of a homologous esterase (SABP2). These experiments identified residues outside the active site that 1) orient and position the catalytic residues for more efficient catalysis and 2) create a tunnel needed for the exit of products from the buried active site. Using these insights, we next engineered the natural esterase SABP2 to be 6.5-fold faster. These results demonstrate the importance of distant residues on catalysis and suggest ways to engineer more efficient enzymes for biocatalysis.
Bio: Romas Kazlauskas studied chemistry at the Massachusetts Institute of Technology (Ph.D.) and Harvard University (postdoc with George Whitesides). He worked at General Electric Company (1985-88) and McGill University, Montreal, Canada (1988-2003) and is currently a professor in Biochemistry, Molecular Biology and Biophysics at the University of Minnesota. He has been a visiting professor in Germany, Sweden and South Korea. He is an expert in protein engineering of enzymes for biocatalysis.
Dr. Romas Kazlauskas