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

 - Fructokinase (EC 2.7.1.4) (gene scrK).
 - 6-phosphofructokinase isozyme 2 (EC 2.7.1.11) (phosphofructokinase-2) (gene
   pfkB). pfkB is a minor phosphofructokinase isozyme in Escherichia coli  and
   is not evolutionary related to the major isozyme (gene pfkA).
 - Ribokinase (EC 2.7.1.15) (gene rbsK).
 - 1-phosphofructokinase   (EC 2.7.1.56)  (fructose 1-phosphate kinase)  (gene
   fruK).
 - Inosine-guanosine kinase (EC 2.7.1.73) (gene gsk).
 - Tagatose-6-phosphate kinase (EC 2.7.1.-) (phosphotagatokinase) (gene lacC).
 - Escherichia coli hypothetical protein yeiC.
 - Escherichia coli hypothetical protein yeiI.
 - Escherichia coli hypothetical protein yihV.

All the above kinases are proteins of from 310 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.

-Consensus pattern: [AG]-G-x(0,1)-[GP]-x-N-x-[STA]-x(6)-[GS]-x(9)-G
-Sequences known to belong to this class detected by the pattern: ALL,  except
 for inosine-guanosine    kinase,    yeast   ribokinase,   Zymomonas   mobilis
 fructokinase and Escherichia coli yihV.
-Other sequence(s) detected in SWISS-PROT: 6.

-Consensus pattern: [DNS]-[PSTV]-x-[SAG](2)-[GD]-D-x(3)-[AG](2)-[LIVMF]-
                    [LIVMSTA]
-Sequences known to belong to this class detected by the pattern: ALL,  except
 for Zymomonas mobilis fructokinase.
-Other sequence(s) detected in SWISS-PROT: NONE.

-Expert(s) to contact by email: Reizer J.
                                jreizer@ucsd.edu

-Last update: June 1994 / Patterns and text revised.

[ 1] Wu L.-F., Reizer A., Reizer J., Cai B., Tomich J.M., Saier M.H. Jr.
     J. Bacteriol. 173:3117-3127(1991).
[ 2] Orchard L.M.D., Kornberg H.L.
     Proc. R. Soc. Lond., B, Biol. Sci. 242:87-90(1990).
[ 3] Blatch G.L., Scholle R.R., Woods D.R.
     Gene 95:17-23(1990).