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PROSITE documentation PDOC00504

pfkB family of carbohydrate kinases signatures


It has been shown [1,2,3] that the following carbohydrate and purine kinases are evolutionary related and can be grouped into a single family, which is known [1] as the 'pfkB family':

  • Fructokinase (EC (gene scrK).
  • 6-phosphofructokinase isozyme 2 (EC (phosphofructokinase-2) (gene pfkB). pfkB is a minor phosphofructokinase isozyme in Escherichia coli and is not evolutionary related to the major isozyme (gene pfkA). Plants 6-phosphofructokinase also belong to this family.
  • Ribokinase (EC (gene rbsK).
  • Adenosine kinase (EC (gene ADK).
  • 2-dehydro-3-deoxygluconokinase (EC (gene: kdgK).
  • 1-phosphofructokinase (EC (fructose 1-phosphate kinase) (gene fruK).
  • Inosine-guanosine kinase (EC (gene gsk).
  • Tagatose-6-phosphate kinase (EC (phosphotagatokinase) (gene lacC).
  • Escherichia coli hypothetical protein yeiC.
  • Escherichia coli hypothetical protein yeiI.
  • Escherichia coli hypothetical protein yhfQ.
  • Escherichia coli hypothetical protein yihV.
  • Bacillus subtilis hypothetical protein yxdC.
  • Yeast hypothetical protein YJR105w.

All the above kinases are proteins of from 280 to 430 amino acid residues that share a few region of sequence similarity. We have selected two of these regions as signature patterns. The first pattern is based on a region rich in glycine which is located in the N-terminal section of these enzymes; while the second pattern is based on a conserved region in the C-terminal section.


Some bacterial fructokinases belong to the ROK family <PDOC00866>.

Last update:

April 2006 / Pattern revised.

Technical section

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

PFKB_KINASES_1, PS00583; pfkB family of carbohydrate kinases signature 1  (PATTERN)

PFKB_KINASES_2, PS00584; pfkB family of carbohydrate kinases signature 2  (PATTERN)


1AuthorsWu L.-F., Reizer A., Reizer J., Cai B., Tomich J.M., Saier M.H. Jr.
TitleNucleotide sequence of the Rhodobacter capsulatus fruK gene, which encodes fructose-1-phosphate kinase: evidence for a kinase superfamily including both phosphofructokinases of Escherichia coli.
SourceJ. Bacteriol. 173:3117-3127(1991).
PubMed ID1850730

2AuthorsOrchard L.M.D., Kornberg H.L.
TitleSequence similarities between the gene specifying 1-phosphofructokinase (fruK), genes specifying other kinases in Escherichia coli K12, and lacC of Staphylococcus aureus.
SourceProc. R. Soc. Lond., B, Biol. Sci. 242:87-90(1990).
PubMed ID1981619

3AuthorsBlatch G.L., Scholle R.R., Woods D.R.
TitleNucleotide sequence and analysis of the Vibrio alginolyticus sucrose uptake-encoding region.
SourceGene 95:17-23(1990).
PubMed ID2174811

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