Team:British Columbia

Harnessing microbial teamwork to degrade and valorize biomass

Development of modern biorefining processes is required to reduce our reliance on petroleum-derived chemicals and fuels. One solution has been to use microbial catalysts to transform renewable biomass into bio-equivalent chemicals. However, a major obstacle to implementing inductrial-scale bioprocesses is the high cost of processing raw biomass into a usable form.

Plant biomass, called lignocellulose, is an abundant and extremely strong polymer that has evolved to resist degradation. Inefficiencies with product yield are inevitably incurred as a consequence of the metabolic strain experienced by single microbial strains that comprise most modern bioprocessing systems.

This year, our team aimed to make the processing and utilization of renewable biomass feedstocks cheaper and more efficient by building a microbial community able to transform biomass into useful products.

Crescentium

A “divide and conquer” approach to split the tasks of biomass degradation and valorization between two microbial species, Caulobacter crescentus and Escherichia coli.

The Bacterial Community

Caulobacter crescentus: The subject of novel research at the University of British Columbia, the robust surface expression system in the bacterium C. crescentus can be engineered to display biomass-transforming enzymes.

Escherichia coli: A well-developed industrial workhorse, E. coli serves as a perfect host for many engineered biosynthetic pathways that transform glucose into valuable products.

The Transformation Process

When combined, we can harness the power of “microbial teamwork” to degrade and valorize biomass. C. crescentus surface-expressed cellulases cleave parts of lignocellulose to release glucose in to the system. E. coli consumes glucose and using engineered biosynthetic pathways, converts it into valuable chemicals.