Question

Describe how phosphofructokinase activity is regulated in glycolysis? Also further describe the effects of the regulation?

Answer 1

PFK ( phosphofructokinase) is main regulatory of glycolysis cycle. This enzyme catalyzed conversion of fructose 6 phosphate in to fructose 1,6 bis phosphate. This is am allosteric enzyme, various allosteric modulators affect activity of the enzyme.  

Main allosteric activator of the enzyme are ADP, H ion , fructose 2,6 bis phosphate ( F 2,6 BP) .

Allosteric inhibitors are , all the high energy status signals ATP, NADH, citrate

Fructose 2,6 bis phosphate, is an important regulator of glycolysis and gluconeogenesis. F 2, 6 BP activate PFK 1 thus promote glycolysis. At ths same time F2,6 BP inhibits fructose 1,6 bis phosphates and inhibit gluconeogenesis. Thus this compound regulates both glycolysis and gluconeogenesis.  

This regulation has been explained in attached image below

fructose 6 phosphate f263P ATP CB citrate, no App to 2 poki -ATP, NADH fructose 6 Bisphosphalo fructose 6 Poy Pricz fructose PRKI N ter bis fructose 2,6 bis phophate pohosphetuse → fructosel,s bis phosphate 1 Glycolzer