Development of a Synthetic Biology Platform to Optimize the Process and Products of Enzymatic Lignin Disruption

Synthetic biology is an emerging research area, which aims to design and engineer novel biological parts, devices and systems to solve specific challenges. The goal of our research project is to develop a synthetic biology platform to optimize the degradation process and the products of lignin disruption for the production of aromatic chemicals. To this end, 20 different genes, encoding lignin peroxidases, manganese peroxidases, versatile peroxidases and laccases, were selected from GeneBank and their cDNA was synthesized in a modular genetic part format by de novo gene synthesis. Gene expression libraries were constructed for Saccharomyces cerevisiae and Pichia pastoris by using inABLE gene assembly technology established by Ingenza Ltd. and the strains showing ligninolytic activity were screened out using a high-throughput screening method. Functional expression of 11 ligninolytic enzymes was confirmed from those libraries and their enzymatic characteristics were investigated to select the enzymes with the desired properties. Furthermore, production levels of the ligninolytic enzymes were optimized by modifying culture conditions. As a result of these optimizations, we have successfully expressed all four different classes of ligninolytic enzymes using this synthetic biology platform.