Talk:Phosphofructokinase 1

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PFK1 is inhibited by its product, ATP. This is confusing as ATP is not its immediate product... I think this should be clarified
 * I assume this has been clarified by now. It seems straight forward to me. PDCook (talk) 01:19, 17 February 2010 (UTC)

It seems this article confuses eukaryotic and prokaryotic forms of the enzymes throughout. The prokaryotic enzyme is tetrameric and regulated by PEP and ADP/ATP, but NOT fructose 2,6-bisphosphate. It's the one shown in the structure.

Each subunit of a eukaryotic PFK, which DOES bind fructose 2,6-bisphosphate, corresponds to two adjacent prokaryotic subunits, fused together in a pseudosymmetric way, so a eukaryotic dimer corresponds to the prokaryotic tetramer. Eukaryotic enzymes can exist as tetramers or even octamers, but these are "higher order" multimers of the basic 2-fold symmetric (or 4-fold pseudosymmetric) architecture. The "pseudo-active sites" on each pseudo-dimeric subunit bind fructose 2,6-bisphosphate instead of the product fructose 1,6-bisphosphate, explaining why it is activating. — Preceding unsigned comment added by Compbiograd (talk • contribs) 19:17, 5 October 2016 (UTC)

Muscle acidosis is not caused by lactic acid
The paragraph below needs to be rewritten: See the Wikipedia article on Lactic acid where exercise is discussed. There is no lactic acid in a muscle cell and lactic acid is not the cause of muscle acidosis.

PFK1 is also inhibited by low pH levels which augment the inhibitory effect of ATP. The pH falls when muscle is functioning anaerobically and producing excessive quantities of lactic acid. This inhibitory effect serves to protect the muscle from damage that would result from the accumulation of too much acid.

Suggested replacement: PFK1 is also inhibited by low pH levels which augment the inhibitory effect of ATP. The pH falls when muscle is functioning anaerobically and producing excessive quantities of hydrogen ions. This inhibitory effect serves to protect the muscle from damage that would result from high acidity. —Preceding unsigned comment added by 216.159.180.253 (talk) 16:14, 15 February 2011 (UTC)

Error in image showing mechanism
The compound labeled ADP in the product side is clearly ATP. Chadwickthezulu (talk) 00:36, 16 August 2022 (UTC)