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PROSITE documentation PDOC00336 [for PROSITE entry PS00433]

Phosphofructokinase signature


Phosphofructokinase (EC (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.


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.

Technical section

PROSITE method (with tools and information) covered by this documentation:

PHOSPHOFRUCTOKINASE, PS00433; Phosphofructokinase signature  (PATTERN)


1AuthorsPoorman R.A. Randolph A. Kemp R.G. Heinrikson R.L.
TitleEvolution of phosphofructokinase--gene duplication and creation of new effector sites.
SourceNature 309:467-469(1984).
PubMed ID6233492

2AuthorsHeinisch J. Ritzel R.G. von Borstel R.C. Aguilera A. Rodicio R. Zimmermann F.K.
TitleThe phosphofructokinase genes of yeast evolved from two duplication events.
SourceGene 78:309-321(1989).
PubMed ID2528496

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