Improved hydrolysis of lignocellulosic biomass through development of thermostable multicatalytic enzymes

Research Project, 2017 – 2019

This project aims to develop new enzymes to enhance the hydrolysis of biomass for biofuel related processes. Enzymatic hydrolysis of biomass is regarded as the most sustainable alternative, but is currently also an economical bottleneck as one of the costliest steps in biofuel production. Enzymes degrading plant biomass often consist of multiple modules with different functions, such as catalytic and carbohydrate-binding. Enzymes consisting of multiple catalytic domains are however rare, but have been shown to be able to rival or even outcompete commercial enzyme cocktails, as a result of a substantial synergy effect between closely positioned catalytic domains with complementary activities. Especially in the bacterial genus Caldicellulosiruptor such enzymes are prevalent, though deeper investigations are severely lacking. Here, we will evaluate these unusual type of enzymes and determine their potential to be used in industrial hydrolysis processes. We will also construct novel multicatalytic enzymes through molecular biology tools to obtain a large library of different enzyme architectures. A special focus is on incorporation of the newly discovered type of oxidative enzymes (lytic polysaccharide monooxygenases) which have revolutionized the field in later years. The studied enzymes will be optimized for efficient hydrolysis of biomass using industrially relevant biomass (forestry and agricultural waste) and at significantly higher temperatures than what is used today.