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1.

001-es BibID:BIBFORM097685
035-os BibID:(cikkazonosító)30394
Első szerző:Kállay Csilla (vegyész)
Cím:Thermodynamic and structural characterization of the Copper(II) complexes of peptides containing both histidyl and aspartyl residues / Csilla Kállay, Zoltán Nagy, Katalin Várnagy, Gerasimos Malandrinos, Nick Hadjiliadis, Imre Sóvágó
Dátum:2007
ISSN:1565-3633
Megjegyzések:Terminally protected pentapeptides with 2 histidines (Ac-HHVGD-NH2 and Ac-HVGDH-NH2) and the terminally free peptides containing both internal aspartyl and C-terminal histidyl residues (FDAH and VIDAH) have been synthesized, and copper(II) complexes studied by potentiometric, UV-Vis, CD, and EPR spectroscopic techniques in solution. Both thermodynamic and spectroscopic data reveal that side chain donor atoms of aspartyl and histidyl residues have a significant contribution to the metal binding affinity of peptide molecules. In the case of terminally protected peptides, the role of the imidazole-N donor functions is reflected in the enhanced stability of the 3N and 4N coordinated copper(II) complexes. The amino and ?-carboxylate groups of FDAH and VIDAH create a very effective metal binding site with the (NH2, N?, ?-COO?) and (NH2, N?, N?, ?-COO?) coordination modes including the N-termini, while the histidine sites are available for the formation of the (Nim, N?, N?) binding mode resulting in the preference of dinuclear complex formation.
Tárgyszavak:Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
folyóiratcikk
Megjelenés:Bioinorganic Chemistry And Applications. - 2007 (2007), p. 1-9. -
További szerzők:Nagy Zoltán (1974-) (vegyész) Várnagy Katalin (1961-) (vegyész) Malandrinos, Gerasimos Hadjiliadis, Nick Sóvágó Imre (1946-) (vegyész)
Pályázati támogatás:T048352
OTKA
T042722
OTKA
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DOI
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2.

001-es BibID:BIBFORM095291
Első szerző:Kállay Csilla (vegyész)
Cím:Copper(II) complexes of terminally protected pentapeptides containing three histidyl residues in alternating positions, Ac-His-Xaa-His-Yaa-His-NH2 / Csilla Kállay, Katalin Várnagy, Gerasimos Malandrinos, Nick Hadjiliadis, Daniele Sanna, Imre Sóvágó
Dátum:2006
ISSN:1477-9226
Megjegyzések:Copper(II) complexes of the pentapeptides Ac-HisAlaHisValHis-NH2, Ac-HisValHisAlaHis-NH2, Ac-HisProHisAlaHis-NH2, Ac-HisAlaHisProHis-NH2, Ac-HisGlyHisValHis-NH2 and Ac-HisValHisGlyHis-NH2 have been studied by potentiometric, UV-Vis, CD and EPR spectroscopic methods. It has been found that the pentapeptides are efficient ligands for the complexation with copper( II) and exhibit an outstanding versatility in the co-ordination geometry of complexes. The presence of three histidyl residues provides a high possibility for the formation of macrochelates via the exclusive binding of imidazole-N donor atoms. The macrochelation suppresses, but cannot preclude the deprotonation and metal ion co-ordination of amide functions and the species [CuH-2L] and [Cu2H-4L] predominate at physiological pH in equimolar solutions and in the presence of excess metal ions, respectively. It is also clear from the data that both C-terminal and internal histidyl residues can work as the anchoring sites for metal binding and subsequent amide deprotonation resulting in the formation of co-ordination isomers and dinuclear species in equimolar solutions and in the presence of excess metal ions, respectively. In more alkaline solutions ( pH similar to 10) a third amide function can be deprotonated and co-ordinated in the species [CuH-3L](-) with (N-, N-, N-, N-im) co-ordination. The dinuclear species [Cu2H-5L](-) and [Cu2H-6L](2-) containing hydroxide ions and/or imidazolato bridges are formed at high pH in the presence of excess of metal ions. The insertion of one proline into the sequence preceding histidyl residues hinders the deprotonation of amide functions at that site and the formation of only mononuclear complexes was observed with these peptides.
Tárgyszavak:Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
folyóiratcikk
Megjelenés:Dalton Transactions. - 2006 : 38 (2006), p. 4545-4552. -
További szerzők:Várnagy Katalin (1961-) (vegyész) Malandrinos, Gerasimos Hadjiliadis, Nick Sanna, Daniele (1956-) (vegyész) Sóvágó Imre (1946-) (vegyész)
Pályázati támogatás:T 048352
OTKA
T 042722
OTKA
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DOI
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3.

001-es BibID:BIBFORM010522
Első szerző:Kállay Csilla (vegyész)
Cím:Thermodynamic and structural characterization of the macrochelates formed in the reactions of copper(II) and zinc(II) ions with peptides of histidine / Csilla Kállay, Katalin Várnagy, Gerasimos Malandrinos, Nick Hadjiliadis, Daniele Sanna, Imre Sóvágó
Dátum:2009
ISSN:0020-1693
Megjegyzések:Copper(II) complexes of the peptides Ac-HisSarHis-NH2, Ac-HisSarHisSarHis-NH2 and Ac-HisSarHisSarHisSarHis-NH2 have been studied by potentiometric, UV-Vis, CD and EPR spectroscopic methods. Stability constants for the corresponding zinc(II) complexes have also been reported. The formation of M(II)-2N(im), M(II)-3N(im) and M(II)-4N(im) bonded macrochelates was suggested in the pH range 5-7. The macrochelates were, however, not stable enough to prevent metal ion hydrolysis in slightly alkaline solutions. In the case of copper(II) complexes, the metal ion promoted deprotonation and coordination of the amide groups of histidyl residues were also suggested. The stability constants of macrochelate complexes were compared to the literature data reported for the macrochelates of the other peptides of histidine. It was found that the thermodynamic stability of macrochelate species is largely influenced by the number and location of histidyl residues in the peptide backbone. The highest stability was obtained for the HXHYH-type sequences, while the distant arrangement of histidyl residues resulted in a significant reduction of the stability constants. (C) 2008 Elsevier B. V. All rights reserved.
Tárgyszavak:Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
Megjelenés:Inorganica Chimica Acta. - 362 : 3 (2009), p. 935-945. -
További szerzők:Várnagy Katalin (1961-) (vegyész) Malandrinos, Gerasimos Hadjiliadis, Nick Sanna, Daniele (1956-) (vegyész) Sóvágó Imre (1946-) (vegyész)
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4.

001-es BibID:BIBFORM002676
Első szerző:Kállay Csilla (vegyész)
Cím:Zinc(II) binding ability of tri-, tetra- and penta-peptides containing two or three histidyl residues / Csilla Kállay, Katalin Ősz, Adrienn Dávid, Zita Valastyán, Gerasimos Malandrinos, Nick Hadjiliadis and Imre Sóvágó
Dátum:2007
Tárgyszavak:Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
Megjelenés:Dalton transactions. - 36 (2007), p. 4040-4047. -
További szerzők:Sóvágó Imre (1946-) (vegyész) Dávid Adrienn Valastyán Zita Malandrinos, Gerasimos Hadjiliadis, Nick Ősz Katalin (1975-) (vegyész)
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5.

001-es BibID:BIBFORM006215
Első szerző:Rajković, Snežana
Cím:Complex formation processes of terminally protected peptides containing two or three histidyl residues. Characterization of the mixed metal complexes of peptides / Snežana Rajković, Csilla Kállay, Richárd Serényi, Gerasimos Malandrinos, Nick Hadjiliadis, Daniele Sanna and Imre Sóvágó
Dátum:2008
Megjegyzések:Copper(II), nickel(II) and zinc(II) complexes of the peptides Ac-HVVH-NH2 and Ac-HAAHVVH-NH2 have been studied by potentiometric, UV-vis, CD, EPR and NMR spectroscopic measurements. Both tetra and heptapeptides can form relatively stable macrochelates with copper(II), nickel(II) and zinc(II) ions, in which the ligands are coordinated via the side-chain imidazole functions. Formation of the macrochelates slightly suppresses, but cannot prevent the copper(II) and nickel(II) ion promoted deprotonation and coordination of the amide functionalities. The overall stoichiometry of the major species is [MH-3L](-) with a 4N (=N-, N-, N-, N-im) coordination mode. In the case of Ac-HAAHVVH-NH2, coordination isomers of this species can exist with a preference for copper(II) or nickel(II) binding at the internal histidyl residue. In the copper(II)-Ac-HAAHVVH-NH2 system, the presence of the two anchoring sites results in the formation of dinuclear complexes. The existence of these species requires the involvement of amide functions in metal binding. Both equilibrium and spectroscopic data support the fact that the copper(II) ions of the dinuclear species are independent from each other providing a good chance for the formation of various mixed metal complexes. It was found that zinc(II) is not able to significantly alter the copper(II) binding of the heptapeptide, but it can occupy the uncoordinated histidyl sites. The formation of the copper(II) - nickel(II) mixed species was obtained in alkaline solutions and CD spectra suggest the statistical distribution of the two metal ions among the histidyl residues. The binding of HAAHVVH to palladium(II) is exclusive below pH 8 and the mixed metal species of palladium(II) and copper(II) ions are formed only in slightly basic solutions.
Tárgyszavak:Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
Megjelenés:Dalton Transactions. - 37 (2008), p. 5059-5071. -
További szerzők:Kállay Csilla (1978-) (vegyész) Serényi Richárd Malandrinos, Gerasimos Hadjiliadis, Nick Sanna, Daniele (1956-) (vegyész) Sóvágó Imre (1946-) (vegyész)
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6.

001-es BibID:BIBFORM006223
Első szerző:Zavitsanos, Kimon
Cím:Interaction of Cu(II) and Ni(II) with the 63-93 fragment of histone H2B / Zavitsanos, K., Nunes, A. M. P. C., Malandrinos, G., Kallay, C., Sovago, I., Magafa, V., Cordopatis, P., Hadjiliadis, N.
Dátum:2008
ISSN:1477-9226
Megjegyzések:Chromatin proteins are believed to represent reactive sites for metal ion binding. We have synthesized the 31 amino acid peptide Ac-NSFVNDIFERIAGEASRLAHYNKRSTITSRE-NH2, corresponding to the 63-93 fragment of the histone H2B and studied its interaction with Cu(II) and Ni(II). Potentiometric and spectroscopic studies (UV-vis, CD, NMR and EPR) showed that histidine 21 acts as an anchoring binding site for the metal ion. Complexation of the studied peptide with Cu(II) starts at pH 4 with the formation of the monodentate species CuH2L. At physiological pH values, the 3N complex {N-Im, 2N(-)}, CuL is favoured while at basic pH values the 4N {N-Im, 3N(-)} coordination mode is preferred. Ni(II) forms several complexes with the peptide starting from the distorted octahedral NiH2L at about neutral pH, to a square planar complex where the peptide is bound through a {N-Im, 3N(-)} mode in an equatorial plane at basic pH values. These results could be important in revealing more information about the mechanism of metal induced toxicity and carcinogenesis.N2 - Chromatin proteins are believed to represent reactive sites for metal ion binding. We have synthesized the 31 amino acid peptide Ac-NSFVNDIFERIAGEASRLAHYNKRSTITSRE-NH2, corresponding to the 63-93 fragment of the histone H2B and studied its interaction with Cu(II) and Ni(II). Potentiometric and spectroscopic studies (UV-vis, CD, NMR and EPR) showed that histidine 21 acts as an anchoring binding site for the metal ion. Complexation of the studied peptide with Cu(II) starts at pH 4 with the formation of the monodentate species CuH2L. At physiological pH values, the 3N complex {N-Im, 2N(-)}, CuL is favoured while at basic pH values the 4N {N-Im, 3N(-)} coordination mode is preferred. Ni(II) forms several complexes with the peptide starting from the distorted octahedral NiH2L at about neutral pH, to a square planar complex where the peptide is bound through a {N-Im, 3N(-)} mode in an equatorial plane at basic pH values. These results could be important in revealing more information about the mechanism of metal induced toxicity and carcinogenesis.
Tárgyszavak:Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
Megjelenés:Dalton Transactions. - 44 (2008), p. 6179-6187. -
További szerzők:Nunes, Ana Mónica P. C. Malandrinos, Gerasimos Kállay Csilla (1978-) (vegyész) Sóvágó Imre (1946-) (vegyész) Magafa, Vassiliki Cordopatis, Paul Hadjiliadis, Nick
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