What is life made of?
How does it evolve abiotically?
Where did it emerge?
When will the life cycle end?
The origin of life was a bottom-up evolutionary process of chemical clusters and it can be considered as an open-ended design problem in the context of chemical engineering. Many hypotheses have been explored and reviewed, none of which though has a definite answer yet with regards to the precise mechanism. Recent advances in molecular simulation will have a major role in the field. Finally, the emergence of life is a thermodynamic state function. This property arises from its nano-level structure, creating a life cycle which will never cease to exist until the planet runs out of energy sources.
Introduction
Before the emergence of life there must have been an evolutionary process of chemical clusters. Evolution implies optimisation of the cluster chemistry leading to life and an open-ended design problem. Therefore, the origin of life is also a problem of chemical engineering. This report will explore past and contemporary ideas concerning the origin of life, presenting them primarily in the context of chemical engineering.
The study of the traditional natural sciences, mainly physics, chemistry, biology and earth science is crucial in understanding natural phenomena. However, the study of the origin of life can be advanced further through more specialised disciplines like chemical engineering, synthetic biology and astrobiology which try to encompass all the above. In a sense, researching the origin of life is not an easy task mainly for two reasons. Firstly, life emerged in an era not accessible to us through historical reconstruction and secondly it requires the integration of all the scientific disciplines into the science of everything.
The main objective of this paper is to examine the various hypotheses regarding the origin of life from the chemical engineering perspective. Since there is no definite answer, necessary factors which were rate determining for organic life synthesis in the form of early cells would be presented in an attempt to trace back evolution to the last universal common ancestor (LUCA) cell. LUCA is the ancestor of all life on earth and it can lead us to the path of evolution, as well as its origin.
Life emerged almost 3.8 billion years ago based on isotopic evidence (1). Possibly a cataclysmic event accelerated the process but cannot be entirely considered because of lack of the dynamics that existed on Earth. A feasible scenario would be a sufficient energy influx surpassing the required activation threshold energy into a small system containing the right ingredients and resulting in autopoiesis (2); a system capable of reproducing and maintaining itself.
Therefore, critically reviewing the existing hypotheses would help determine to what extent life was formed endogenously or delivered exogenously. Furthermore, given that we know that the earth is a biosphere which acts as an open system with certain control loops to stabilise the environment, the question of where the origin of life occurred arises. With the discovery of extremophiles, certain options include deep sea hydrothermal vents, land-based volcanic pools, bubble formation in the oceans, the deep subsurface etc.
An alternative way to examine the origin of life is by firstly observing and secondly experimenting in potentially habitable exoplanets. Lastly, with the aid of computational methods, a simulation approach could solve the mystery once and for all. Chemical engineers have been at the forefront in recent advances in molecular simulation, driven by the higher speed of computational hardware and new algorithms (3).
Thanks for reading my article.I am planning to make this a mini series of posts based on an academic research project that I've written this semester. Your feedback is highly appreciated.
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