How can tiny organisms affect our planet’s future?

And what will be the role of AI in carbon-fixating organisms helping humanity to thrive?

"Synthetic biology is not just about engineering life—it's about designing life for the benefit of humanity."

Drew Endy

Earth; our home.

Climate; the changing weather conditions.

Carbon; allows life - human beings included - to exist on Earth.

If you were to Google “climate change news” how might you end up feeling? Hopeless. Possibly even terrified. Powerless, angry, depressed. I feel you. It makes me feel the same way. However, after every thunderstorm there's a rainbow - or, how some fools such as myself like to put it, hope.

“What does that look like?” You ask. Well, as the subheadline might suggest, it’s… *drum roll*: Artificial Intelligence (AI).

Yes, that all powerful technology that can create delicious recipes from a simple photo of the food in your fridge. The same tech that can write your sick note to give your boss tomorrow.

That same generative tech can be used to generate hope - with carbon fixating organisms (CFOs).

Carbon Fixation and Carbon Fixating Organisms (CFOs)

First, to get everyone on the same page, let’s explain in simple terms what they are and why they are so important for life on Earth to thrive. If you’re already familiar with what CFOs are (I don’t mean Chief Financial Officers, you sneaky), you can skip to later in this article where we talk about the state-of-the-art. 

CFOs are living organisms, like plants and algae, that have the ability to take inorganic carbon dioxide from the air and turn it into organic compounds as food for themselves, through a process known as biological carbon fixation. These organic molecules, such as carbohydrates, are essential for their growth and survival - and by growing from carbon dioxide alone, these organisms play a crucial role in the carbon cycle by being the first step of the food chain.

“Synthetic biology has the potential to embed intelligence into the Earth system, allowing humans to scale life and make informed decisions based on data.” 

Jesse Zondervan, during a Science Spotlight episode with ValleyDAO

There’s two main categories of CFOs: autotrophs and heterotrophs. (I know they sound like Autobots and Decepticons from Transformers, but in this case, both are good.)

So autotrophs, like plants and algae, can make their own food using sunlight or inorganic substances. They are like nature's little chefs that turn carbon dioxide into energy through photosynthesis. On the other hand, heterotrophs, such as animals and humans, cannot make their own food from carbon dioxide. In terms of the food chain, they’re like nature’s customers in the Earth restaurant; relying on consuming other organisms, like plants, to get the energy they need to survive. Both types of organisms are needed to preserve the balance of the carbon cycle and make life happen on Earth.

Finally, the process of carbon fixation is basically nature’s way by which these living organisms can convert inorganic carbon to organic compounds using primarily photosynthesis or, in some cases, chemosynthesis.

Those same organisms have many ways at their disposal to convert CO2 into energy and nutrients. Those natural ways are called carbon fixation pathways (CFP), and as far as we know, there’s six of them. The most common CFP is the Calvin-Benson-Bassham (CBB) cycle, commonly found in plants, algae, and some bacteria. It involves three main steps: carbon fixation, reduction, and regeneration of the starting molecule.

“Synthetic biology can help recycle resources more efficiently, relieve pressure on Earth's stabilizing systems, and create positive feedback loops for soil health and the carbon cycle.”

Jesse Zondervan, during a Science Spotlight episode with ValleyDAO

State-of-the-art

Now that you know these terms, let’s dive into how CFOs and AI can work together like Batman and Robin (or Emmanuelle Charpentier and Jennifer A. Doudna for the SynBio folks in the know).

Some scientists use machine-learning - and in many recent cases, AI - when genetically engineering CFOs to help optimize and enhance the efficiency of their CFPs, or else to design new and artificial pathways. Those pathways can be diverted to capture and convert carbon dioxide into useful products such as biofuels (i.e. more sustainable and environmentally friendly fuel) and biopolymers (i.e. materials from living organisms with lower environmental impact than alternatives).

Recent state-of-the-art research has shown an extremely promising upcoming role of AI in engineering carbon fixating organisms and pathways. This study published in November 2020 in the Frontiers in Microbiology Publication for instance developed artificial autotrophic microorganisms with CO2 fixation engineered into them. The authors used AI and synthetic biological tools to develop artificial CFPs, and those pathways were then used to transform the originally heterotrophic microorganisms into autotrophic ones, effectively laying the foundation for the development of efficient carbon fixation cell factories*. 

*Side note for those less aware: when I say cell factories, I mean specialized living cells, like bacteria or yeast, that can create products - in this case using carbon dioxide as a raw material - such as biofuels or biopolymers.

Another study published in September 2021 in the BioDesign Research Journal used computational methods to analyze and compare natural and artificial carbon fixation pathways. The study finds that the CETCH cycle, and a new artificial one, have the potential to match the best natural cycles in terms of product-substrate yield. However, the Calvin-Benson-Bassham cycle still performed better in terms of activity. Still, it demonstrated the potential of artificial CFPs to be used for specific use cases in biotechnology applications.

The final study published in March 2022 in the Environmental Science and Pollution Research Journal used AI and fuzzy logic (a type of decision making AI when there’s unclear or imprecise information) to model carbon fixation by microalgae. In effect, they created a model to predict the carbon fixation by microalgae based on several factors - such as light intensity, temperature, and nutrient concentration. Their results showed that the AI and fuzzy logic approach accurately predicted the carbon fixation rate by microalgae; which is fantastic since it can thus contribute to the development of sustainable carbon capture and utilization technologies.

By translating more research like that discussed above, we can reach this solarpunk future that I (and I hope you, my sustainable reader) dream about. The technology might be at its infancy and need more time to mature. However, with AI and human curiosity mixed in, there’s potential to speed it up and create or improve upon existing organisms. The sustainable future that humanity deserves is within our reach, and the solutions exist.

It’s just up to us to create and use them.

References:

1. Biology Online. (2023, December 6). Carbon fixation - Definition and Examples - Biology Online Dictionary. Biology Articles, Tutorials & Dictionary Online. https://www.biologyonline.com/dictionary/carbon-fixation 

2. Libretexts. (2023, August 18). 32.16: Fixing Carbon fixation. Biology LibreTexts. https://bio.libretexts.org/Bookshelves/Biochemistry/Fundamentals_of_Biochemistry_%28Jakubowski_and_Flatt%29/Unit_IV_-_Special_Topics/32:_Biochemistry_and_Climate_Change/32.16:__Fixing_Carbon_Fixation 

3. Garritano, A. N., Song, W., & Thomas, T. (2022). Carbon fixation pathways across the bacterial and archaeal tree of life. PNAS Nexus, 1(5). https://doi.org/10.1093/pnasnexus/pgac226 

4. Liang, B., Zhao, Y., & Jian-Ming, Y. (2020). Recent advances in developing artificial autotrophic microorganism for reinforcing CO2 fixation. Frontiers in Microbiology, 11. https://doi.org/10.3389/fmicb.2020.592631 

5. Löwe, H., & Kremling, A. (2021). In-Depth computational analysis of natural and artificial carbon fixation pathways. Biodesign Research/Biodesign Research, 2021. https://doi.org/10.34133/2021/9898316 

6. Kushwaha, O. S., Uthayakumar, H., & Kumaresan, K. (2022). Modeling of carbon dioxide fixation by microalgae using hybrid artificial intelligence (AI) and fuzzy logic (FL) methods and optimization by genetic algorithm (GA). Environmental Science and Pollution Research International, 30(10), 24927–24948. https://doi.org/10.1007/s11356-022-19683-0 

7. Valley DAO. (2024, February 5). Science Spotlight with Jesse Zondervan [Video]. YouTube.