Context and Motivation
Climate change and the urgent need to transition from a fossil-based economy to a circular bioeconomy have driven the search for sustainable biotechnological solutions. A key strategy to achieve this transition is the development of microbial production strains capable of utilizing CO2-derived one-carbon (C1) substrates, such as formate, to generate valuable bioproducts. One of the most promising metabolic pathways enabling this is the reductive glycine pathway (rGlyP), which is highly efficient, energy-conserving, and relatively easy to engineer. However, despite recent advances in metabolic engineering, the growth performance of engineered formatotrophic strains remains suboptimal for industrial applications.
Traditional methods for optimizing these synthetic pathways rely on adaptive laboratory evolution (ALE), which involves random mutation and natural selection. While effective, ALE is time-consuming and often introduces unwanted off-target mutations, making it an inefficient method for precise pathway optimization. Recent advancements in directed evolution and synthetic biology have provided new tools for improving enzyme function and pathway efficiency, but these tools have primarily been optimized for Escherichia coli and are challenging to implement in other bacterial hosts.
Overall Objectives
The EvoZyme project aims to address these challenges by developing a synthetic diversification platform that enables the targeted evolution of enzymes in multiple bacterial hosts. The platform will allow for precise and accelerated genetic diversification of key metabolic enzymes, optimizing microbial growth and productivity in a way that circumvents the limitations of traditional ALE. The project is structured around two primary objectives:
Development of a synthetic diversification platform – A system capable of hypermutating a gene of interest (GOI) in a targeted manner while allowing seamless transfer of the evolved GOI to various bacterial hosts. This ensures pathway optimization without introducing off-target effects in the host genome.
Optimization of the reductive glycine pathway (rGlyP) through targeted evolution of the glycine cleavage system (GCS) – The GCS is the core enzyme complex responsible for key metabolic conversions within rGlyP. EvoZyme will apply the diversification platform to improve the efficiency of the GCS, enabling enhanced formatotrophic growth in industrially relevant microbes (E. coli, Cupriavidus necator, Pseudomonas putida).
By achieving these objectives, EvoZyme will pave the way for a new approach to enzyme engineering, establishing a broadly applicable diversification tool that could optimize other critical biosynthetic pathways beyond rGlyP.
Pathway to Impact
The EvoZyme project is expected to significantly advance synthetic metabolism by providing a novel, adaptable platform for improving enzymatic functions in diverse microbial hosts. The key expected impacts include:
Scientific and Technological Impact:
• Introduction of a highly efficient and versatile enzyme evolution tool for synthetic biology and metabolic engineering.
• Generation of optimized formatotrophic strains capable of efficiently converting CO2-derived substrates into biomass and valuable bioproducts.
• Improved understanding of the molecular mechanisms underlying enzyme optimization, with applications in industrial biotechnology.
Economic and Industrial Impact:
• Acceleration of biotechnological strain development, reducing the time and cost associated with optimizing metabolic pathways.
• Enhancement of biomanufacturing processes, improving the feasibility of using engineered microbes for large-scale production of bio-based chemicals.
• Potential commercialization of the diversification platform as a broadly applicable tool for enzyme engineering in academia and industry.
Societal and Environmental Impact:
• Contribution to a sustainable bioeconomy, reducing dependency on fossil fuels and mitigating CO2 emissions.
• Support for achieving multiple United Nations Sustainable Development Goals (SDGs), particularly those related to climate action, sustainable industry, and responsible consumption.
• Increased public engagement in synthetic biology through open science practices and science communication initiatives.
Setting the Scene for EvoZyme
The EvoZyme project operates at the intersection of biotechnology, synthetic biology, and metabolic engineering, tackling one of the key barriers to a bio-based circular economy—the efficient engineering of microbial metabolism. By creating a powerful and tunable enzyme diversification platform, EvoZyme will not only improve biotechnological production processes but also provide an essential tool for future research in metabolic engineering and synthetic metabolism. With a strong focus on scientific innovation, industrial applicability, and environmental sustainability, EvoZyme has the potential to transform how microbial strains are engineered, paving the way for a new era of sustainable bioproduction.
