17-ERACoBioTech: Sustainable production of added value chemicals from SynGas-derived methanol through Systems and Synthetic Biology approaches

Lead Research Organisation: University of Nottingham
Department Name: School of Life Sciences

Abstract

One of the greatest challenges facing society is the future sustainable production of chemicals and fuels from non-petrochemical resources while at the same time reducing greenhouse gas emissions. The recalcitrance of lignocellulose to deconstruction for feedstock purposes is making the economic development of biologically-based processes extremely challenging. This has led to the concept of using low-cost, abundant one-carbon (C1) feedstocks. Here the focus has been on using C1 gases, such as CO/CO2 and CH4, sourced as a waste from industrial processes, anaerobic digestion or deliberately formed as synthesis gas (syngas) through the gasification of any waste containing biomass (agricultural/ forestry residues and municipal solid waste) or by the reformation of shale gas. Such an approach is not without its issues. The mass transfer of gases into the liquid phase in reactors places constraints on reactor design and performance, while in the case of aerobic chassis the additional presence of H2, and O2 is potentially explosive. In contrast, as a liquid, methanol does not suffer from mass transfer issues in fermenters and is more easily stored and transported. It can be made from many sustainable feedstocks, including biomass, MSW, biogas, waste CO2, and even renewable electricity.

The case for using methanol as a feedstock to make chemicals and fuels is, therefore, compelling. In this project, BIOMETCHEM, we will exploit the progress made in developing effective genetic systems for a bacterium known as Eubacterium limosum to derive engineered strains able to produce the value-added products from biomass derived methanol. Process strain will be derived through a combination of interdisciplinary methodologies, including systems biology (INSA, University of Toulouse), synthetic biology (UNOTT, University of Nottingham), metabolic engineering (ULM, University of Ulm), enzymology (UFRA, University of Frankfurt), and methanol fermentation development (All Partners). Responsible Research Innovation (RRI) practices will be embedded within the programme of work through the participation of dedicated Social Scientists from the Synthetic Biology Research Centre (SBRC) at Nottingham. Life Cycle Analysis (LCA) and Techno-Economic Analysis (TEA) will be undertaken by Nottingham in partnership with Johnson Matthey. BIOMETCHEM will lead to the development of new Sustainable production and conversion processes based on methanol feedstocks derived from gasified (syngas) biomass residues and wastes or from industrial by-products (FT waste streams). This will lead to new value-added products, useful in the pharmaceutical/food additive industries and the chemical industry, respectively.

Ultimately, the developments made will lead to new sustainable industrial processes. Moreover, by combining resources and expertise, BIOMETCHEM connects research partners in three different countries (France, Germany and UK) with different but complementary scientific and technological expertise, thereby maximising resources and sharing the risks, costs and skills. The participants represent some of Europe's leading experts in anaerobic metabolism, and in particular C1 feedstocks. The amalgamation of their expertise and resources provides the critical mass needed to compete with the rest of the world.

Technical Summary

A methanol-based production system will be derived by combining interdisciplinary methodologies in the following workpackages:-

WP1: Project Management (Nottingham)
Administrative and scientific coordinator is Nottingham.

WP2: RRI, Responsible Research and Innovation (Nottingham)
Social scientists will implement a RRI approach to map public perceptions and concerns over the envisaged process technology.

WP3. Systems analysis of the process chassis (Toulouse)
Comprehensive characterization of metabolic pathways and their regulation will enable maximisation of products yields.

WP4: SynBio Tool Development (Nottingham)
Nottingham will design and test tools to facilitate the overproduction of the enzymes involved.

WP5: Implementation of the production pathways (Ulm)
Codon optimised synthetic genes will be combined in various configurations together with different transcriptional/ translational signals.

WP6: Characterisation of the methanol utilisation pathway (Frankfurt)
Derived recombinant enzymes of the methanol assimilation pathway will be characterised to identify potential bottlenecks.

WP7 Increasing productivity through protein scaffolding and CRISPR-Cas9 genome editing (Nottingham/Ulm)
Improvements to yields will be sought through the elimination of competing pathways and protein scaffolding.

WP8: Optimisation of Fermentation Performance (Toulouse/Nottingham)
Optimisation of product yields will be undertaken in fermenters, and involve adaptive laboratory evolution approaches.

WP9: LCA, Life Cycle Analysis (Nottingham; Johnson Matthey)
Environmental impacts will be quantified to allow the setting of critical research targets to improve the overall environmental performance of production.

WP10: Technoeconomic analysis (Nottingham; Johnson Matthey)
Existing technoeconomic models of biorefinery systems and methanol production from syngas will infrom the design of commercially systems.

Planned Impact

One of the greatest challenges facing society is the future sustainable production of chemicals and fuels from non-petrochemical resources while at the same time reducing greenhouse gas emissions. The recalcitrance of lignocellulose to deconstruction for feedstock purposes is making the economic development of biologically-based processes extremely challenging. This has led to the concept of using low-cost, abundant one-carbon (C1) feedstocks. Here the focus has been on using C1 gases, such as CO/CO2 and CH4, sourced as a waste from industrial processes, anaerobic digestion or deliberately formed as synthesis gas (syngas) through the gasification of any waste containing biomass (agricultural/ forestry residues and municipal solid waste) or by the reformation of shale gas. Such an approach is not without its issues. The mass transfer of gases into the liquid phase in reactors places constraints on reactor design and performance, while in the case of aerobic chassis the additional presence of H2, and O2 is potentially explosive. Consequently, there is increasing interest in the use of methanol as a C1 feedstock. As a liquid, methanol does not suffer from mass transfer issues in fermenters and is more easily stored and transported. The focus of BIOMETCHEM is to derive process organisms, engineered to produce the added value products GABA (gamma-aminobutyric acid) and 1,4-Butanediol (BDO) from biomass derived methanol. GABA has considerable use as a pharmaceutical and is a major active constitute in foods, such as germinated brown rice, cheese, gabaron tea, and shochu. Biosynthetic routes to GABA are considered more promising than via chemical synthesis as they have a simple reaction procedure, high catalytic efficiency, mild reaction condition and are environmental friendly. The world market for GABA in functional foods and relaxing drinks is estimated to be 300 million $ at an average price of 7 USD per kilogram. Theoretical yields of GABA production from methanol is 0.92g/g and GABA production is associated to CO2 consumption.

Butanediol (BDO) and its derivatives is used in a broad spectrum of applications in the chemical industry; amongst others in the manufacturing of technical plastics, polyurethanes, solvents, electronic chemicals and elastic fibres. The world market for 1, 4 BDO is around 4 billion USD; at an average price of 2 USD per kilogram. Theoretical yields of BDO production from methanol is 0.73 g/g a value much higher that the theoretical yield from glucose (0.51 g/g).

By combining resources and expertise, BIOMETCHEM connects research partners in three different countries (France, Germany and UK) with different but complementary scientific and technological expertise, thereby maximising resources and sharing the risks, costs and skills. The participants represent some of Europe's leading experts in anaerobic metabolism, and in particular C1 feedstocks. The amalgamation of their expertise and resources provides the critical mass needed to compete with the rest of the world, in particular the US and China, where there is considerable activity in the C1 field. The development of processes based on syngas derived methanol is moreover, unlikely to be beset by the problems encountered by Ineos Bio, whose MSW, syngas-based process was halted by hydrogen cyanide contamination in the syngas, which was toxic to its process organism. Moreover, methanol availability is dramatically increasing. Worldwide, over 90 methanol plants have a combined production capacity of 110 million metric tons (almost 36.6 billion gallons or 138 billion liters). Global demand reached 70 million metric tons in 2015 (23 billion gallons/87 billion litre) and is projected to reach USD 54.16 billion by 2021. Methanol is typically produced by reforming natural gas with steam and then converting the resulting syngas into. But it can be made from many sustainable feedstocks, including biomass and MSW.