A study by Dr. Terry Kee and associates at the University of Leeds (U.K.) and published in the journal Chemical Communications framed their research question this way: Scientists argue about the origin of life in many different ways, especially about which came first – replication or metabolism. Did the early forms of life, simple cells in all probability first develop the ability to replicate or was the basic metabolism more important? There is, however, another question – what was the energy source?
Currently nearly all living things use energy that is derived from the sun (via photosynthesis), which is consumed in the form of sugars and then converted in the cells to the ultimate biological energy source known as ATP (Adenosine Triphosphate). It probably didn’t start that way. The chemical pathways of photosynthesis and ATP production have now had billions of years to develop. In the beginning was probably something else, much simpler.
Thinking about what could be a likely form for the earliest source of energy, Dr. Kee put it this way:
“You need enzymes to make ATP and you need ATP to make enzymes,” explained Dr Kee. “The question is: where did energy come from before either of these two things existed? We think that the answer may lie in simple molecules such as pyrophosphite which is chemically very similar to ATP, but has the potential to transfer energy without enzymes.”
The most important point is that phosphorus was – and is – a key element of life. Phosphorus is highly reactive meaning that it virtually always bonds with other molecules. In living things (organics) it’s a component of DNA, RNA, ATP, and the phospholipids that form all cell membranes. How phosphorus came to exist on Earth is still a matter of controversy. Dr. Kee is with those who think that it may have come from meteorites and then was transformed into pyrophosphite by volcanic action.
This line of research has now been picked up by the American space agency (NASA) to further investigate its role in abiogenesis (the origin of life).