HUMAN SERUM AMYLOID-P COMPONENT BINDS TO A SPECIFIC PEPTIDE IN THE PRESENCE OF CALCIUM

Human serum amyloid P component (SAP) binds to a carboxyl-terminal pep tide of residues 160-204 of SAP itself in the presence of calcium. A s et of sequentially overlapping decapeptides covering the entire length of residues 160-204 of SAP was synthesized on polyethylene pins to be used for binding assay, and six overlapping peptides in residues e-Ar g-Gly-Tyr-Val-Ile-Ile-Lys-Pro-Leu-Val-Trp-Val) were found to have equa lly high affinity for SAP. The validity of using peptides on polyethyl ene pins was shown by the binding assay using 11-residue soluble pepti de corresponding to residues 194-204. Replacement of the Lys or the li e residues with Glu abolished the binding activity. (C) 1994 Academic Press, Inc.