J. Biol. Chem., Vol. 255, Issue 4, 1492-1496, Feb, 1980
Amino acid sequence at the allosteric site of sheep heart phosphofructokinase
L Weng, RL Heinrikson and TE Mansour
Covalent modification of sheep heart phosphofructokinase with the affinity
labeling reagent p-fluorosulfonyl[14C]benzoyl-5'-adenosine caused a loss of
allosteric properties. This modification appears to occur at the binding
site that is specific for the allosteric activators AMP, cAMP, and ADP
(Mansour, T.E., and Colman, R.F. (1978) Biochem. Biophys. Res. Commun. 81,
1370-1376). In the current study, the site of modification has been
demonstrated to be a lysine residue. A nonapeptide containing a covalently
bound [14C]carboxybenzenesulfonyl group attached to alysine residue has
been isolated following tryptic digestion. The amino acid sequence of the
peptide is Asn-Phe-Ala-Thr- Lys-Met-Gly-Ala-Lys. The fifth residue in this
sequence, lysine, contained the covalently bonded reagent.