Decoding the Climate Crisis through C1 Bioeconomy

Written by George William Ssendagala, Edited by Jonathan Hamp and Caroline Babisz.

On July 27, 2023, the resonating words of United Nations Secretary-General António Guterres echoed a profound shift in our world's climate narrative: "The era of global warming has drawn to a close, making way for the era of global boiling". This striking declaration coincided with a scorching summer, leaving vacationers sweltering in the heat of the hottest season recorded.

The question looms large: how did we arrive at this critical juncture? Casting our gaze back, it becomes evident that those who came before us held a deep reverence for fossil fuels since the inception of the Industrial Revolution. This infatuation has catalysed an incremental alteration in our planet's temperature, now recognised as a staggering 1.5°C rise, attributed to the emission of greenhouse gases from using fossil resources. Nevertheless, the consequences are not limited to sweltering summers, they have cascaded into glacial retreats, rampant wildfires, and droughts, all poised to imperil humanity's existence.

Confronted with these challenges head-on, the natural carbon cycle, which should have absorbed excess carbon emissions, has become imbalanced and overwhelmed (1). In response, nations and regions across the globe have championed innovative strategies to grapple with this crisis. Among these visionary endeavours is the Green Deal, the European Union's flagship initiative, to steer Europe toward carbon neutrality by 2050 (2).

Trash to Treasure: The Astonishing Power of Circular Bioeconomy

The Green Deal also champions the concept of a circular economy (a system where material never become waste and nature is regenerated), a concept that, when combined with the bioeconomy (an economic system that is based on the sustainable production and utilisation of biological resources), gives birth to the dynamic notion of a circular bioeconomy (an economic framework that combines the principles of both a circular economy and a bioeconomy). This represents a departure from the traditional linear approach of use and disposal, advocating for a regenerative framework that respects the finite bounds of our planet's resources (2). Through this waste-to-treasure narrative, we witness the transformation of waste resources, even the harmful waste gases contributing to the current climate crisis, into valuable assets.

Greenhouse gases such as carbon dioxide (CO2) and methane (CH4), together with carbon monoxide (CO), methanol (CH3OH), and formate (HCOOH), form a class of molecules classified as one-carbon (C1) compounds. From a fundamental point of view, carbon is a necessary building block for many commonplace goods, such as biofuels, medicines, and packaging materials. It has been argued that a circular bioeconomy should eliminate, effectively utilise, and sequester more carbon than it emits into the atmosphere (3).

The use of C1 molecules as raw materials to fuel industrial processes, favoured for their abundance and affordability of which production expenses account for over 50% makes bioproduction processes relying on C1 molecules more feasible (4). These environmental and production benefits could explain why research into using C1 molecules for bioproduction is rising. However, the use of C1 molecules necessitates cutting-edge efforts to re-engineer and repurpose molecular structures, which is illuminated next.

Hacking Molecules for a Cooler World

At the forefront of this scientific ingenuity are researchers and visionaries who are leveraging molecular manipulation to address pressing climate challenges. In recent decades, the realm of biotechnology has been engaged in an unrelenting quest for microorganisms engineered to produce economically valuable compounds (5). In a parallel undertaking, the pursuit of cell factories adept at harnessing the potential of C1 compounds is underway, an achievement attainable either through natural processes or synthetic manipulation. In a remarkable display of scientific prowess, researchers have unlocked the art of metabolism manipulation, orchestrating novel biochemistries that facilitate the uptake of these compounds, channelling them into biomass.

This realm of innovation aptly coined “rational design” encompasses an array of methodologies for example computational design, metabolic engineering, modularisation, and adaptive laboratory evolution. With the inefficiencies that typically hinder natural processes, today's scientists have harnessed the power of rational design to enhance the efficiency of existing pathways and forge entirely new, nature-inspired routes in biocatalysts as sumarised in figure 1 below.

Strikingly, reports detailing the deployment of this innovative technology have revealed a profound revelation. These biocatalysts exhibit fuctional versatility, from being able to thrive in varying gas compositions of carbon dioxide, hydrogen, and carbon monoxide to resilience in the face of impurities, simplifying processes that might have necessitated purification steps (6).

However, as we traverse this landscape of progress, it is imperative to note that many pioneering companies have dared to leap into the arena of C1 compounds, each positioning itself at the forefront of this revolutionary charge.

Bio-Revolution: Meet the Pioneers of a Cooler Tomorrow!

Pioneers at the forefront of this movement, reshaping the contours of our future and ushering in a new era of bio-inspired solutions take center stage in this section. Get ready to be inspired by their groundbreaking technologies and visionary insights for a greener tomorrow!

• Calysta
• Electrochaea
• LanzaTech
• Phase Biolabs
• Twelve

The Eco-Reality Check

Amid the ongoing discourse on the sustainability of green technologies, a critical point has emerged: not all that glimmers with a green hue is genuinely sustainable. A pivotal practice has taken the stage to safeguard against mere appearances and the risk of greenwashing allegations – the rigorous evaluation of a product's or process's impact through a life cycle assessment (LCA) as illustrated in figure 2. This assessment delves deep into the intricate web of a product's social, economic, and environmental (SEE) implications, painting a holistic picture of its journey from inception to its eventual culmination.

In a world where the spotlight often falls on environmental concerns, let us focus on LanzaTech, a prime example that illuminates the significance of this concept. While using ethanol as the product, their first-ever study reported a 60% reduction in carbon footprint compared with conventional fossil fuels (8). Seven years later through a series of optimisations, another study reported that their gas fermentation technology was carbon negative while using acetone and isopropanol as the products (6).

These narratives underscore a paramount truth – the innovation journey is an ever-flowing river continuously nourished by research and development (R&D). Moreover, nestled within this truth lies the crux of the matter: that the quest for deeper understanding, enhanced efficiency, and boundless evolution holds the key to shaping a sustainable and impactful future.

Navigating Challenges and Paradoxes

From a scientific standpoint, the financial and temporal hurdles of R&D phase, emerge as contenders that can push fledgling enterprises to extinction. Those resilient enough to persevere, narrow their focus to crafting high-value compounds. Yet, the conundrum remains – despite their low value, bulky compounds contribute to the ongoing climate dilemma necessitating alternatives. Regarding operational intricacies, gases obtained via pyrolysis whose temperatures soar beyond 100°C are associated with expenses tied to cooling them to biocatalyst-friendly 20-30°C. Furthermore, increased carbon dioxide levels hinder the growth of various species, often accompanied by harmful levels of nitrogen and sulphur oxides (8). Consequently, pursuing robust hosts and creating detoxification routes is indispensable to unlocking the application spectrum for present-day biocatalysts.

Transitioning our lens to the societal landscape, the bioeconomy concept springs forth with circularity as its guiding principle. As companies form strategic alliances and embrace the allure of green marketing, they firmly etch their footprints within the realm of the green transition. Yet, an intriguing question arises: Could the well-intentioned commodification of by-products inadvertently usher in a stabilisation scenario or even a surge in waste volumes? More intriguingly, is there a paradoxical risk that society might, in its endeavour to pivot towards a circular economy, unwittingly forge a "linear economy lock-in"? (9) As the curtain rises on this transition's inception, a lingering querry echoes – could this seemingly clear vision evolve into an unpredictable catalyst for future challenges?

Embedding Systemic Thinking in Policies for Effective Transition

The increasing world population will continue to drive the supply and demand of commodities to sustain daily human life. However, understanding that the ultimate switch from fossil fuels will put enormous strain on agriculture and forestry is imperative. Additionally, this change is not happening as fast as we want implying that policies aimed at interconnected and complex relationships within a system rather than individual sectors in isolation should be focal (10). Systemic thinking is a valuable tool for comprehending and managing the bioeconomy because it allows consideration of the system's complex interrelationships and makes more informed decisions about optimising it. Therefore, it should be at the base of legislation and policies so that innovative technologies like those that utilise C1 molecules, can be deployed widely and rationally.

Embracing a Cooler, Brighter Future

As the intricate tapestry of our world's climate narrative unfurls, the call for collective action resounds urgently. However, within the challenge lies an opportunity to rewrite the trajectory of our planet's fate by turning waste into treasure! The era of global boiling can be reversed by rallying our support around this movement of converting carbon emissions into valuable resources that power our future. Committing resources and backing ventures in the C1 Bioeconomy is not just a choice, it's a necessity. Let us not merely be spectators in this pivotal moment; let us be agents of change. Together, let us shape a future that our planet deserves – a future that is not only cooler but brighter.

References

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2. Fetting C. THE EUROPEAN GREEN DEAL. ESDN Report, December 2020, ESDN Office, Vienna.

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4. Charubin K, Papoutsakis ET. Direct cell-to-cell exchange of matter in a synthetic Clostridium syntrophy enables CO2 fixation, superior metabolite yields, and an expanded metabolic space. Metab Eng. 2019 Mar 1;52:9–19.

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8. Liu H, Cheng T, Zou H, Zhang H, Xu X, Sun C, et al. High titer mevalonate fermentation and its feeding as a building block for isoprenoids (isoprene and sabinene) production in engineered Escherichia coli. Process Biochem. 2017 Nov;62:1–9.

9. Greer R, von Wirth T, Loorbach D. The Waste-Resource Paradox: Practical dilemmas and societal implications in the transition to a circular economy. J Clean Prod. 2021 Jun;303:126831.

10. Marvik OJ, Philp J. The systemic challenge of the bioeconomy: A policy framework for transitioning towards a sustainable carbon cycle economy. EMBO Rep. 2020 Oct 5;21(10):e51478.

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