Interactions of Cu2+ ions with chicken prion tandem repeats.
The potentiometric and spectroscopic (EPR, UV-Vis, CD) data have shown that the chicken prion hexa-repeat (Ac-His-Asn-Pro-Gly-Tyr-Pro-NH(2)) is a very specific ligand for Cu(2+) ions. The His imidazole is an anchoring binding site, then the adjacent amide nitrogen coordinates as a second donor. The presence of Pro at position 3 induces binding of phenolate oxygen as a third donor atom. The tridentate coordination dominates around physiological pH. Similar to human octapeptide fragments, chicken tandem repeats exhibit a cooperative effect in binding Cu(2+) ions, although chicken peptides are much less effective in metal ion coordination.
Stańczak
Pawel
P
Faculty of Chemistry, University of Wrocław, F. Joliot-Curie 14, 50-383 Wroclaw, Poland.
Łuczkowski
Marek
M
Juszczyk
Paulina
P
Grzonka
Zbigniew
Z
Kozłowski
Henryk
H
D000595:Amino Acid Sequence; D000818:Animals; D002413:Cations, Divalent / Q000378:metabolism*; D002645:Chickens; D003300:Copper / Q000378:metabolism*; D004121:Dimethyl Sulfoxide; D006801:Humans; D008024:Ligands; D008969:Molecular Sequence Data; D010455:Peptides / Q000737:chemistry / Q000378:metabolism; D011328:Prions / Q000737:chemistry* / Q000378:metabolism*; D020449:Repetitive Sequences, Amino Acid; D012996:Solutions; D013057:Spectrum Analysis; D014867:Water
D002413:Cations, Divalent; D008024:Ligands; D010455:Peptides; D011328:Prions; D012996:Solutions; D014867:Water; D003300:Copper; D004121:Dimethyl Sulfoxide