2
$\begingroup$

I have read it repeatedly that 'all living organisms use ATP as an energy currency etc' and 'some use GTP in addition'. However I am yet to find a reliable resource, rather than just quora/reddit/researchgate posts, that states this.

Also, would it be possible to create a synthetic organism which does not use ATP? Or GTP? What might be the best energy currency to use then?

$\endgroup$
  • $\begingroup$ ATP is of course not the only energy currency molecule, but it is universal in the sense of being a primary source of free energy obtained from both aerobic and anaerobic fermentation/respiration. In terms of free energy of hydrolysis, it is not the 'best': both PEP and creatine-phosphate have considerably higher values. Other (so-called) 'high-energy' compounds are acetyl-CoA, acetyl-phosphate,UTP and ITP. $\endgroup$ – user1136 Sep 26 '19 at 14:22
  • $\begingroup$ For the definitive reference on the history of ATP as universal free energy donor see Metabolic generation and utilization of phosphate bond energy published in 1941 by Lipmann $\endgroup$ – user1136 Sep 26 '19 at 14:22
3
$\begingroup$

Well your request for a source is rather like asking who first reported that 2+2=4. Not quite, but that should give the idea to someone who has not studied biochemistry. I doubt that you will find a source, but the following from Jacques Monod — the Nobel laureate — is worth quoting:

“Anything found to be true of E. coli must also be true of elephants.”

In fact, this turns out not to be true for anything, but it is true of the role of ATP.

The better question, I think, is not what the source of such a quotation is, but what is the evidence for such an opinion. The evidence that has accumulated over the last 80 years or so is from examining the metabolic pathways present in different organisms, and, more recently, sequencing their genomes to identify the genes for various enzymes. What has been observed is a core of common pathways, involving a core mechanism of energy metabolism involving ATP. This is consistent with the idea that this arose early in evolution and was fixed in the last common ancestor of living things.

If you want a more recent source to the ideas above, I suggest another SE Biology question, Immortal genes common to all organisms, may provide a starting point.

$\endgroup$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.