Autocatalytic Sets
Autocatalytic sets are a series of reactions that are able to catalyze their entire production. (In plain English, it is a bunch of chemical reactions that do not need introduction of any outside chemical to sustain itself. Think of it as a closed system where everything is balanced and self-sustaining.) Although the term autocatalytic was originally based in molecular chemistry, the fields of sociology and economics have taken the concept and applied it metaphorically towards their own theories that focus outside of a chemical context.
Autocatalytic Set: Chemical A (CA) drives Chemical B (CB) drives Chemical C (CC) which in turn, after a series of chain reactions, recreates CA. A familiar form of autocatalytics can be seen within the phases of mitosis and meiosis, where a single cell divides into daughters of itself:
This idea was hypothesized by an American theoretical biologist known as Stuart Kauffman. Kauffman argued this was the basis for the replication of living organisms (this was before the concept of DNA was known).
Another instance of the autocatalytic set is derived from the ideas of German chemist Manfred Eigen. This idea was known as the “hypercycle.” The term hypercycle is known in chemistry as the organization of molecules in a cyclic fashion. This cyclic formation self-replicates and creates a single larger cyclic formation.
With these two ideas, a difficult to work with biologist, Tibor Gánti helped build upon his original hypothesis of a simpler model than what we currently have (what is accepted by the majority of the scientific community). That idea is the chemoton. I first learned about the Chemoton in a National Geographic article recommended to me by Apple News (Apple News sucks to use if you are a scholar btw, so don’t use it lol). Essentially, the chemoton uses 3 things to secure its chemical survival-
- Metabolic Pathway to synthesize the chemicals needed for life
- Informational Template that stores how a chemical molecule is to be constructed (think DNA but in simpler way).
- Barrier-Membrane to trap the chemicals-essentially creating a “floating bag of chemicals” some may refer to as a cell. This membrane should be non-reactive and would like to clump together. Here on Earth, that is the phospholipid bilayer.
Right now there are many synthetic biologists and biochemists at work trying to create this “bag of chemicals” known as the chemoton. However, no reproduction of an actual chemoton has actually come to fruition. But given enough time and with the advancements of science and technology, we will surely find out or at least develop a better understanding what is required for the key ingredients of life to form.
References:
Eigen M, Schuster P. The hypercycle. A principle of natural self-organization. Part A: Emergence of the hypercycle. Naturwissenschaften. 1977 Nov;64(11):541–65. doi: 10.1007/BF00450633. PMID: 593400.
Gene. (n.d.). Genome.Gov. Retrieved December 22, 2020, from https://www.genome.gov/genetics-glossary/Gene
He may have found the key to the origins of life. So why have so few heard of him? (2020, December 14). Science. https://www.nationalgeographic.com/science/2020/12/he-may-have-found-the-key-to-origins-of-life-tibor-ganti-chemoton/
Originally published at http://moleculardrugs.wordpress.com on December 22, 2020.
