Scientific approaches and hypotheses
The conditions of industrial saccharification vary markedly from those typically found during enzymatic break down of cellulose in Nature. Therefore, “natural enzymes” (wild-types) may not be optimal for the industrial process. In RESAB we use rational and semi-rational approaches to find enzyme variants with faster catalysis under industrial conditions. The work is based on iterative circles which may be coarsely described as:
- Identification of potential bottlenecks
We characterize the kinetics of a given cellulase experimentally and model the experimental data to elucidate molecular origins of the rate limiting steps in the catalytic cycle. - Design of variants
We analyze the structure of the wild-type enzyme and devise mutations that are likely to make the enzyme less prone to the rate limiting factor identified under 1. - Produce variants
We use site directed mutagenesis to express mutant enzymes. These enzyme variants are then shuttled into point 1 for update of hypothesis and continuous optimization.