This week a very interesting new paper was published that explores the nature of ancient (perhaps prebiotic) chemistry that could have undergirded the kind of metabolism that we now associate with life.
If you have ever taken a biology class, then you have learned about ATP. (And perhaps then forgotten about. Understandable.) ATP is the energy currency of almost all life forms. Cells convert other kinds of energy to ATP, which is then a standard “power pack” that can be plugged into all sorts of other chemical reactions in the cell. The P in ATP is phosphate. It’s hard to picture life without phosphate and ATP. But there must have been some kind of biochemistry before phosphate, because ATP is made by fairly elaborate metabolic systems. When thinking about biochemistry in the early days of life (or before life), it seems we need metabolism that can be powered without relying on chemical conversion of energy into currency.
In the new paper, the scientists used a systems biology approach to look at all metabolism on earth after all phosphate-dependent components are erased from the picture. They find what appears to be a “core” phosphate-free metabolic system that can run without the need for ATP.
The paper is pretty technical, and the accompanying mini-review is too, but the story is worth a look. And the paper is open access. I don’t think the mini-review is open access but I will be happy to send it to anyone who can’t get it online. The paper also includes a “PaperClip” which is a nice audio conversation with the authors.
It’s not my main area of expertise but I would be glad to answer questions.
Paper: Remnants of an Ancient Metabolism without Phosphate
Mini-reivew: Energy in Ancient Metabolism