3253-17-6Relevant academic research and scientific papers
Cu(II) Binding to the Peptide Ala-His-His, a Chimera of the Canonical Cu(II)-Binding Motifs Xxx-His and Xxx-Zzz-His
Gonzalez, Paulina,Vileno, Bertrand,Bossak, Karolina,El Khoury, Youssef,Hellwig, Petra,Bal, Wojciech,Hureau, Christelle,Faller, Peter
, p. 14870 - 14879 (2017)
Peptides and proteins with the N-terminal motifs NH2-Xxx-His and NH2-Xxx-Zzz-His form well-established Cu(II) complexes. The canonical peptides are Gly-His-Lys and Asp-Ala-His-Lys (from the wound healing factor and human serum albumin, respectively). Cu(II) is bound to NH2-Xxx-His via three nitrogens from the peptide and an external ligand in the equatorial plane (called 3N form here). In contrast, Cu(II) is bound to NH2-Xxx-Zzz-His via four nitrogens from the peptide in the equatorial plane (called 4N form here). These two motifs are not mutually exclusive, as the peptides with the sequence NH2-Xxx-His-His contain both of them. However, this chimera has never been fully explored. In this work, we use a multispectroscopic approach to analyze the Cu(II) binding to the chimeric peptide Ala-His-His (AHH). AHH is capable of forming the 3N- and 4N-type complexes in a pH dependent manner. The 3N form predominates at pH ～ 4-6.5 and the 4N form at ～ pH 6.5-10. NMR experiments showed that at pH 8.5, where Cu(II) is almost exclusively bound in the 4N form, the Cu(II)-exchange between AHH or the amidated AHH-NH2 is fast, in comparison to the nonchimeric 4N form (AAH). Together, the results show that the chimeric AHH can access both Cu(II) coordination types, that minor changes in the second (or further) coordination sphere can impact considerably the equilibrium between the forms, and that Cu kinetic exchange is fast even when Cu-AHH is mainly in the 4N form.
Zinc Complexes of Histidine-Containing Di- and Tripeptides
Foerster, Martin,Vahrenkamp, Heinrich
, p. 541 - 550 (2007/10/02)
Nine dipeptides and one tripeptide containing histidine were converted into analytically pure zinc complexes.Four different compositions were observed.The peptides used as or converted into the monoacids LH (HisGly, GlyHis, HisPhe, HisHis) form the compounds ZnL2 (11a, 12-14) and alternatively (HisGly, HisGlyGly) the compounds ZnL(BF4) (11b, 20).The peptides used as amides (HisGlyNH2, HisMetNH2) act as neutral ligands in the compounds ZnL2(ClO4)2 (15, 16).The three remaining peptides (HisAsp, AlaHis, β-AlaHis) behave like diprotonic acids LH2 forming the compounds ZnL (17-19).Spectra and solubilities indicate that complexes 11a, 13, 15, and 16 are mononuclear containing two chelating peptides bound by their amino and imidazole nitrogen atoms.All other complexes seem to be coordination polymers in some of which the amide N and O atoms are involved in the coordination.This was proven by a structure determination for Zn(GlyHis)2 (12) in which the zinc ions are coordinated octahedrally by two histidine N, two amino N, and two amide O atoms of four peptide residues. - Key Words: Histidine peptides/ Zinc complexes/ Composition/ Solid-state structure
Amino Acids and Peptides. III. Synthesis of Model Peptides Related to Cytochrome P-450
Kawasaki, Koichi,Maeda, Mitsuko,Tamura, Hiromi,Ohashi, Sumiko,Yoshimura, Tetsuhiko,Hatayama Etsuji et al.
, p. 1717 - 1723 (2007/10/02)
Various tetra- and pentapeptides with Cys and Ser (Thr, Tyr, His) at the N- and C-terminals, respectively, were synthetized as model peptides of the apoprotein of cytochrome P-450.The optical spectra of synthetic peptide-hemin complexes were measured and the results are discussed.Keywords - cytochrome P-450; synthetic Cys-containing peptide; peptide-hemin complex; optical spectrum of peptide-hemin complex
