Alzheimer's beta-amyloid peptide: affinity for metal chelates.
Alzheimer's amyloid peptide, A beta(1-42) and its fragments, A beta(1-28) and A beta(1-16), were chromatographed on IDA-M(II) columns (M: Cu2+, Ni2+ and Zn2+). The retention of A beta(1-42) and its fragments on IDA-Cu(II) could not be reversed in decreasing a gradient of pH, from 7.0 to 4.0. All A beta peptides were recovered from IDA-Ni(II) columns in a decreasing pH gradient from 7.0 to 4.0, within the pH range from 5.6 to 5.1. A beta(1-42) peptide was strongly retained on IDA-Zn(II) at pH 4.0, but its A beta(1-28) and A beta(1-16) were only transiently retained on IDA-Zn(II) columns when applied at pH 6.1. We submit that histidine clusters, residing both in the Alzheimer's beta-amyloid peptide and in most of the APP/APLP superfamily of proteins, constitute high-affinity binding sites for immobilized metal chelates.
Balakrishnan
R
R
Biophysics Department, Roswell Park Cancer Institute, Buffalo, New York, USA. rbalakri@cmgm.stanford.edu
Parthasarathy
R
R
Sulkowski
E
E
D000544:Alzheimer Disease; D000595:Amino Acid Sequence; D016229:Amyloid beta-Peptides / Q000378:metabolism*; D002614:Chelating Agents / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D003300:Copper / Q000378:metabolism; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007098:Imino Acids / Q000378:metabolism; D008670:Metals / Q000378:metabolism*; D008969:Molecular Sequence Data; D009532:Nickel / Q000378:metabolism; D010446:Peptide Fragments / Q000378:metabolism; D015032:Zinc / Q000378:metabolism
D016229:Amyloid beta-Peptides; D002614:Chelating Agents; D007098:Imino Acids; D008670:Metals; D010446:Peptide Fragments; D003300:Copper; D009532:Nickel; D015032:Zinc; C008109:iminodiacetic acid