Rational Engineering of Advanced Clostridia for Transformational Improvements in Fermentation
acronym: REACTIF

RESULTS of REACTIF: Presentation can be found here.

Project coordinator:
- Chief Scientific Officer Edward Green - Green Biologics Limited, Abingdon - UK
Project leader:
- Dr. Andrew Dustan - Weyland AS, Blomsterdalen - Norway
- Prof. Dr. Rolf Daniel - Department of Genomic and Applied Microbiology & Göttingen Genomics Laboratory (G2L), Georg-August-University Göttingen - Germany
- Prof. Nigel Minton - Clostridia Research Group (CRG), University of Nottingham - UK
- Prof. Dr. Peter Dürre - University of Ulm - Germany

Challenge & objectives
The production of n-butanol from fermentation of sugar using Clostridia has tremendous industrial potential (n-butanol is an important chemical intermediate for paints plastics, coatings and polymers). Butanol production via fermentation is sustainable, environmentally friendly and offers a lower cost route than synthetic production from oil. However, the conventional fermentation route using Clostridia suffers from low titres and volumetric productivities and a reliance on expensive (and edible) starch-based feedstocks. Commercial implementation requires novel strains with improved fermentation performance and strains capable of fermenting non-food, cellulosic feedstocks.
Our aim is to develop advanced Clostridia strains. Specific deliverables include:

  • identification and characterisation of alleles (genes) responsible for the desired tolerance traits, using genomic approaches, both in historical strains that were used commercially over four decades and in current production strains following the implementation of novel directed evolution strategies;
  • transfer of the identified alleles into current, robust production strains, together with rational metabolic engineering to improve product titres;
  • assessment of strain(s) performance on cellulosic feedstocks at lab and pilot scale.

Expected results & exploitation

Significant project IP will be created during all stages of the project and in particular the identification and manipulation of novel, non-obvious gene targets. The project will deliver advanced Clostridia strains that offer a transformational change to fermentation performance and process economics (projected butanol cost reductions of 300 $/T and a 50% reduction in CAPEX). The strains will exhibit:

  • enhanced growth rates and tolerance to deviations in commercial process conditions;
  • increased tolerance to cellulosic feedstock inhibitors, and;
  • improved tolerance to the end product (butanol).

The commercial outputs of the project will be exploited by Green Biologics Ltd. (GBL) and Weyland, who bridge the commercial supply chain from feedstock to butanol production. They will develop a design brief for an integrated fermentation plant with a cellulosic feedstock and determine production cost together with energy and carbon balances over the complete lifecycle.