Design of metal ion binding peptides.
Two cyclic and branched peptides (PLA and AZU) were synthesized with the aim of reproducing the active site of the blue copper proteins plastocyanin and azurin. Both peptides, designed on the basis of the x-ray structures of Poplar plastocyanin and Alcaligenes denitrificans azurin, contain the same coordinating residues of the parent native proteins. The visible spectra of PLA in the presence of equimolar amount of Cu(II) strongly support the interaction between the peptide and copper(II) ion. The CD titration of AZU with the Hg(II) ion indicates for the formation of two species, [AZUHg]+ and [AZUHg2]3+ having binding constants (Keq) of 3.10(6) and 2.10(4) M-1, respectively.
Fattorusso
R
R
Department of Chemistry, University of Naples Federico II, Italy.
Morelli
G
G
Lombardi
A
A
Nastri
F
F
Maglio
O
O
D'Auria
G
G
Pedone
C
C
Pavone
V
V
D000595:Amino Acid Sequence; D001400:Azurin / Q000138:chemical synthesis / Q000378:metabolism; D001665:Binding Sites; D003300:Copper / Q000737:chemistry*; D015195:Drug Design; D007700:Kinetics; D008667:Metalloproteins / Q000737:chemistry*; D008969:Molecular Sequence Data; D010456:Peptides, Cyclic / Q000138:chemical synthesis* / Q000378:metabolism*; D010970:Plastocyanin / Q000138:chemical synthesis / Q000378:metabolism; D011485:Protein Binding; D013053:Spectrophotometry / Q000379:methods
D008667:Metalloproteins; D010456:Peptides, Cyclic; D001400:Azurin; D003300:Copper; D010970:Plastocyanin