Skip to main content

General Scientific News

Our Friend the Phosphate Group

As for phosphorylation, I’ve had some folks write to talk about the importance of phosphate cleavages for cellular energy production, and about the conformational effects of phosphorylation. All that’s well taken – but I guess what I was getting at yesterday is that (for example) sulfation would seem to be a perfectly reasonable way to modify proteins. Why didn’t life end up using it?

Perhaps the phosphate energy part is the key. That’s such a basic mechanism that enzymes to handle phosphate groups must be archaic indeed. It could be that evolution just found a use for them, since they were there anyway, and that competing methods of post-transcriptional modification (like sulfation) never got off the ground. Of course, there’s always glycosylation – wonder when that kicked in, evolutionarily?