Hungarian sensation about the origin of life
Humanity has been interested in some questions from the beginning. Who are we? Where do we come from? How was life itself created? Gods and creation-myths were born, art of spirit and philosophy revived, based on different series of answers, reports 24.hu.
Since natural sciences lead the research on the origin of life and the answer is being searched for through exploring and modelling exact biochemical processes, we are getting much closer to a real solution.
Three requirements of life
Hungarian researchers also contribute to the successes; the newest result of a Hungarian research team on the origin of life has been published in Science journal. Dr Ádám Kun, biologist and senior research fellow of Department of Plant Systematics, Ecology and Theoretical Biology at Eötvös Loránd University (ELTE) was asked what it is exactly about.
Let’s start with how the notion of life could be defined. There is no way to do it briefly, and it is also difficult to use a longer explanation if one tries to make a defensible argument. Ádám Kun says that there are three factors that we require from life:
- To distance itself from its environment, in other words, to be a separate thing. Cells are separated from their environment by a lipid membrane, the cell membrane.
- To carry information about itself. In our case it is the genetic information stored in the DNA.
- To be able to sustain itself. This is ensured by the enzymes doing different kinds of reactions.
How does a system become alive?
The basics of the origin of life are pretty well known. It is known how biologically important molecules are created, and what simple molecules are needed to create them. We are doing well with exploration of the biochemical processes in the background; the required molecules can be created and they work in a way that we want them to.
Now, the big question becomes how the living system is actually made up from these known substances: if we put the needed ingredients in a ball and stir them, it will not make a living cell. A not-yet known organizer principle is needed to the formation of a living organism.
The research today is examining what, for example, happens, if some important components are put together, what changes can happen, and how “alive” the final result can become. It is like a large puzzle, which is still full of empty places – the whole picture will be done by connecting all the small partial results of scientists sometime in the future.
The system is collapsed by parasites
Small mosaics, just like the years-long research of ELTE, in collaboration with a French experimental laboratory. The aim was to prove the theory of Eörs Szathmáry biology professor, according to which the enzymes have to be locked in a lipid membrane in order to keep the information sustaining the system. If it does not happen the so-called parasites invade the system and block its working, after a while.
It is called system, because this “mixture” of molecules cannot be mentioned differently. Although Ádám Kun would be able to define it accurately, but we do not want all our other readers click away from this article except our practicing biologist readers.
These organisations do not make the cut of a living being, but they can produce essential processes for life.
So we have a working enzyme, which can be copied by the system, in other words, it “reproduces”. But the mistakes are unavoidable during copying and mutant enzymes are created as a result –explains Ádám Kun. Let’s call the parasites “molecules”, that receive the products of the enzymes without themselves contributing to the metabolism.
They use the resources but do not add anything to the working of the system. The parasites are copied faster, they are present in the following generations in greater and greater content – as a final result the prevalence of the parasites displace the enzyme and the whole system collapses and “dies”.
Separation is the solution
To avoid these primitive, not yet living organisms, those should be locked in some kind of a membrane. In our case this meant water-drops of ten picoliters – one picoliter is thousand-billion times smaller than a litre. Let’s say syntactic cells as real cells are nothing less, but an enclosure watery solution.
Beside this the right RNS enzyme had to be chosen, and also the copying, its sensation, the sensation of the processes done by it, and other things had to be solved. This way the work of long years and the collaboration of École Supérieure de Physique et de Chimie Industrielles in Paris, one of the most modern laboratories were needed.
The experiment proved what the theory said: as soon as the systems were locked in a membrane only the ones reproduced that worked. Parasites appeared during the copying in this case, too, but only those “cells” moved on that contained enough enzymes needed for the functioning among the parasites.
To make it clearer: via the membrane the synthetic cells divided the large whole into smaller protected units creating several smaller systems instead of a large one. This way even if some of them were suppressed by the parasites, others “survived”, “reproduced” and natural selection did not let the whole thing collapse.
It works
Let’s imagine a boat competition: only those get to the finish where everyone rows in the same direction. All the others are scattered, just like evolution scatters the ones incapable of living – but closed systems are needed for the selection. The researchers have shown that the RNS enzymes locked in the membrane are able to sustain despite the parasites of their mutants.
The origin of life has not been solved with this, but, according to Ádám Kun, “we are more certain that it could happen in a way that we think it did”.
More can be read about the theory and the experiment with scientific details, but in a clear way on Ádám Kun’s blog. The authors of the research appeared in Science are the staff of the Department of Plant Systematics, Ecology and Theoretical Biology of ELTE, MTA-ELTE-MTM Ecology Research Gropup and MTA-ELTE – Theoretical Biology and Evolutionary Ecology Research Group: Eörs Szathmáry academic, Ádám Kun senior research fellow and András Szilágyi senior research fellow.
Photo: 24.hu
Copy editor: bm
Source: 24.hu
