Alex McColgan

It's impure.

There are other molecules floating around that can stabilise the cell walls further, like amino acids.

A diverse range of these building blocks were present on early Earth and are even present in our solar system.

Today, life uses 20 different amino acids to make all the cellular machinery within us like enzymes and ion channels, as well as larger structures like muscle and hair.

There is a miraculous relationship between amino acids that make up proteins and our next building blocks, nucleotides.

A relationship that is important in helping us to understand how life's informational system may have emerged.

The ability of life to create and store information is achieved by nucleotides, which are present today in RNA and DNA.

RNA is believed to be involved in the origin of life because short chains of RNA serve another simpler purpose.

They can also catalyse some chemical reactions, which perhaps kickstarted life's early

Nucleotides have other functions too, and feature in several vitally important molecules like ATP and ADP, the pair of molecules that drive work in a cell, acetyl coenzyme A and vitamin B12.

In fact, every living cell today relies on what's known as the central dogma.

DNA is translated to RNA, which encodes proteins.

This is strong evidence that all life on Earth can be traced back to one lifeform, Leuka, the last universal common ancestor.

The central dogma is a highly evolved system that has redundancy and error correcting built in.

But the ability of RNA to encode proteins may have much simpler beginnings.

One that doesn't require enzymes.

One driven in part by the same physical pressures as fatty acids forming a cell-like structure.

A mechanism that could have introduced information to protocells.

You see, different RNA bases can encode specific amino acids.

This means that a random string of RNA in early protocells could have produced a non-random string of amino acids, which could have conferred an advantage to the protocell containing it.