|PROSITE documentation PDOC00336 [for PROSITE entry PS00433]|
Phosphofructokinase (EC 18.104.22.168) (PFK) [1,2] is a key regulatory enzyme in the glycolytic pathway. It catalyzes the phosphorylation by ATP of fructose 6-phosphate to fructose 1,6-bisphosphate. In bacteria PFK is a tetramer of identical 36 Kd subunits. In mammals it is a tetramer of 80 Kd subunits. Each 80 Kd subunit consist of two homologous domains which are highly related to the bacterial 36 Kd subunits. In Human there are three, tissue-specific, types of PFK isozymes: PFKM (muscle), PFKL (liver), and PFKP (platelet). In yeast PFK is an octamer composed of four 100 Kd α chains (gene PFK1) and four 100 Kd β chains (gene PFK2); like the mammalian 80 Kd subunits, the yeast 100 Kd subunits are composed of two homologous domains.
As a signature pattern for PFK we selected a region that contains three basic residues involved in fructose-6-phosphate binding.Note:
Escherichia coli has two phosphofructokinase isozymes which are encoded by genes pfkA (major) and pfkB (minor). The pfkB isozyme is not evolutionary related to other prokaryotic or eukaryotic PFK's (see <PDOC00504>).Last update:
April 2006 / Pattern revised.
PROSITE method (with tools and information) covered by this documentation:
|1||Authors||Poorman R.A., Randolph A., Kemp R.G., Heinrikson R.L.|
|Title||Evolution of phosphofructokinase--gene duplication and creation of new effector sites.|
|2||Authors||Heinisch J., Ritzel R.G., von Borstel R.C., Aguilera A., Rodicio R., Zimmermann F.K.|
|Title||The phosphofructokinase genes of yeast evolved from two duplication events.|