Munkank soran szamos metalloprotein/enzim femkotő szekvenciajaval azonos oligopeptidet allitottun... more Munkank soran szamos metalloprotein/enzim femkotő szekvenciajaval azonos oligopeptidet allitottunk elő es vizsgaltuk azok femkotő es enzimutanzo sajatsagait. Az eredmenyek hozzajarultak a vizsgalt feherjek (human endostatin, human hisztidin-gazdag glikoprotein (HRG), ket Gram-negativ patogen bakterium Cu,Zn-SOD-ja) tulajdonsagainak, műkodesenek, femion-felveteli folyamatainak jobb megertesehez. Az altalunk korabban es a jelen projektben vizsgalt femkotő oligopeptidek sajatsagainak ismereteben tobb peptidalapu, biomimetikus enzim modellt is terveztunk, melyek utanozni kepesek a metalloproteinek aktiv centrumaban kialakulo femion kornyezetet. E modellek kozul tobb is hatekonynak mutatkozott mind hidrolitikus, mind oxidativ folyamatok katalizisere. Fentiek mellett tobb, nem-peptid tipusu tobbmagvu femkomplexek kialakitasara alkalmas ligandumot vizsgaltunk, melyek hatekonyan es (bazis)szelektiven kepesek foszforsavmonoeszterek es az RNS hidroliziset elősegiteni. | During our work we prepared a number of oligopeptides with sequences identical to the meta binding sites of some selected metalloproteines/enzymes, and we studied their interactions with metal ions, as well as the enzyme mimicking ability of their metal complexes. Our results contributed to the understanding the properties, the catalytic mechanisms and metal uptake processes of the mimicked proteins (human endostatin, human histidine-rich glycoprotein (HRG), two Gram-negative patogen bacterial Cu,Zn-SOD). Based on the metal binding properties of the peptides studied by us (earlier or in this project) we designed some peptide based, biomimetic enzyme models, which are able to mimic the metal ion environment in the active sites of metalloenzymes. Some of these models have notable activity in promoting both hydrolytic and oxidative reactions. Besides, we designed several non-peptide based, dinucleating ligands, too. The Cu(II) and Zn(II) complexes of these ligands are able to promote (base)selective hydrolysis of both phosphomonoesters and RNAs.
ABSTRACT Polysiloxane based devices are frequently used in medical and analytical systems contain... more ABSTRACT Polysiloxane based devices are frequently used in medical and analytical systems containing biopolymers such as proteins, peptide nucleic acids, polyamides. Although silicones are mainly known for their chemical inertness in living systems, physical adsorption does occur. This is sometimes favorable, for example in gas chromatography, but most of the cases it is a serious obstacle of the proper application. These interactions have been studied by molecular docking.
The non-linearity in the temperature dependence of the Kováts index, I (the formation of convex o... more The non-linearity in the temperature dependence of the Kováts index, I (the formation of convex or concave curves) was characterized by the second derivative, d2I/dT2. The expression deduced on a purely mathematical–physicochemical basis is d2I/dT2 = [2TΔS(CH2)dI/dT − 100δΔCp]/TΔG(CH2). The solute-dependent factor for dI/dT, d2I/dT2, and the extreme temperature in the I vs. T relationship is δΔCp, which is the molar solvation heat capacity difference between the solute and a hypothetical n-alkane which elutes at the same time as the given solute, while the solvent-dependent factors are the solvation entropy and free energy of the methylene unit, ΔS(CH2) and ΔG(CH2). Experimentally, convex Ivs.T curves with a minimum are formed when δΔCp ≫ 0, while concave ones with a maximum are observed when δΔCp ≪ 0. In the event of a linear temperature dependence, the former equation can be simplified: dI/dT = 100δΔCp/2TΔS(CH2). The deviation from linearity (higher d2I/dT2) increases with increasing δΔCp values. The model equations were tested from the dataset published by the Kováts group on C78 (19,24-dioctadecyldotetracontane), POH (18,23-dioctadecyl-1-untetracontenol), PCN (1-cyano-18,23-dioctadecyluntetracontane) and TMO (1,38-dimethoxy-17,22-bis-(16-methoxyhexadecyl)-octatriacontane) and by present measurements on the Innowax phase.
ABSTRACT The hydrogen-bonded dimers of l-2-hydroxypropionic were studied by FT-IR and Raman spect... more ABSTRACT The hydrogen-bonded dimers of l-2-hydroxypropionic were studied by FT-IR and Raman spectroscopies and computational methods. The structures of the possible dimers were calculated at the level of ab initio (HF/6-31G(d,p)) quantum chemical method. Calculations on the isolated monomer and dimers revealed a number of possible conformers. Comparison of the calculated and the measured spectra allowed us to choose the dimers most probably present in the aqueous solution of the acid.
... Chem. B 2003, 107, 1302. [ACS Full Text ACS Full Text ]. (25) Vu, QT; Pavlik, M.; Hebestreit,... more ... Chem. B 2003, 107, 1302. [ACS Full Text ACS Full Text ]. (25) Vu, QT; Pavlik, M.; Hebestreit, N.; Pfleger, J.; Rammelt, U.; Plieth, W. Electrochim. Acta 2005, 51, 1117. ... 26) Vu, QT; Pavlik, M.; Hebestreit, N.; Rammelt, U.; Plieth, W.; Pfleger, J. React. Funct. Polym. 2005, 65, 69. ...
Munkank soran szamos metalloprotein/enzim femkotő szekvenciajaval azonos oligopeptidet allitottun... more Munkank soran szamos metalloprotein/enzim femkotő szekvenciajaval azonos oligopeptidet allitottunk elő es vizsgaltuk azok femkotő es enzimutanzo sajatsagait. Az eredmenyek hozzajarultak a vizsgalt feherjek (human endostatin, human hisztidin-gazdag glikoprotein (HRG), ket Gram-negativ patogen bakterium Cu,Zn-SOD-ja) tulajdonsagainak, műkodesenek, femion-felveteli folyamatainak jobb megertesehez. Az altalunk korabban es a jelen projektben vizsgalt femkotő oligopeptidek sajatsagainak ismereteben tobb peptidalapu, biomimetikus enzim modellt is terveztunk, melyek utanozni kepesek a metalloproteinek aktiv centrumaban kialakulo femion kornyezetet. E modellek kozul tobb is hatekonynak mutatkozott mind hidrolitikus, mind oxidativ folyamatok katalizisere. Fentiek mellett tobb, nem-peptid tipusu tobbmagvu femkomplexek kialakitasara alkalmas ligandumot vizsgaltunk, melyek hatekonyan es (bazis)szelektiven kepesek foszforsavmonoeszterek es az RNS hidroliziset elősegiteni. | During our work we prepared a number of oligopeptides with sequences identical to the meta binding sites of some selected metalloproteines/enzymes, and we studied their interactions with metal ions, as well as the enzyme mimicking ability of their metal complexes. Our results contributed to the understanding the properties, the catalytic mechanisms and metal uptake processes of the mimicked proteins (human endostatin, human histidine-rich glycoprotein (HRG), two Gram-negative patogen bacterial Cu,Zn-SOD). Based on the metal binding properties of the peptides studied by us (earlier or in this project) we designed some peptide based, biomimetic enzyme models, which are able to mimic the metal ion environment in the active sites of metalloenzymes. Some of these models have notable activity in promoting both hydrolytic and oxidative reactions. Besides, we designed several non-peptide based, dinucleating ligands, too. The Cu(II) and Zn(II) complexes of these ligands are able to promote (base)selective hydrolysis of both phosphomonoesters and RNAs.
ABSTRACT Polysiloxane based devices are frequently used in medical and analytical systems contain... more ABSTRACT Polysiloxane based devices are frequently used in medical and analytical systems containing biopolymers such as proteins, peptide nucleic acids, polyamides. Although silicones are mainly known for their chemical inertness in living systems, physical adsorption does occur. This is sometimes favorable, for example in gas chromatography, but most of the cases it is a serious obstacle of the proper application. These interactions have been studied by molecular docking.
The non-linearity in the temperature dependence of the Kováts index, I (the formation of convex o... more The non-linearity in the temperature dependence of the Kováts index, I (the formation of convex or concave curves) was characterized by the second derivative, d2I/dT2. The expression deduced on a purely mathematical–physicochemical basis is d2I/dT2 = [2TΔS(CH2)dI/dT − 100δΔCp]/TΔG(CH2). The solute-dependent factor for dI/dT, d2I/dT2, and the extreme temperature in the I vs. T relationship is δΔCp, which is the molar solvation heat capacity difference between the solute and a hypothetical n-alkane which elutes at the same time as the given solute, while the solvent-dependent factors are the solvation entropy and free energy of the methylene unit, ΔS(CH2) and ΔG(CH2). Experimentally, convex Ivs.T curves with a minimum are formed when δΔCp ≫ 0, while concave ones with a maximum are observed when δΔCp ≪ 0. In the event of a linear temperature dependence, the former equation can be simplified: dI/dT = 100δΔCp/2TΔS(CH2). The deviation from linearity (higher d2I/dT2) increases with increasing δΔCp values. The model equations were tested from the dataset published by the Kováts group on C78 (19,24-dioctadecyldotetracontane), POH (18,23-dioctadecyl-1-untetracontenol), PCN (1-cyano-18,23-dioctadecyluntetracontane) and TMO (1,38-dimethoxy-17,22-bis-(16-methoxyhexadecyl)-octatriacontane) and by present measurements on the Innowax phase.
ABSTRACT The hydrogen-bonded dimers of l-2-hydroxypropionic were studied by FT-IR and Raman spect... more ABSTRACT The hydrogen-bonded dimers of l-2-hydroxypropionic were studied by FT-IR and Raman spectroscopies and computational methods. The structures of the possible dimers were calculated at the level of ab initio (HF/6-31G(d,p)) quantum chemical method. Calculations on the isolated monomer and dimers revealed a number of possible conformers. Comparison of the calculated and the measured spectra allowed us to choose the dimers most probably present in the aqueous solution of the acid.
... Chem. B 2003, 107, 1302. [ACS Full Text ACS Full Text ]. (25) Vu, QT; Pavlik, M.; Hebestreit,... more ... Chem. B 2003, 107, 1302. [ACS Full Text ACS Full Text ]. (25) Vu, QT; Pavlik, M.; Hebestreit, N.; Pfleger, J.; Rammelt, U.; Plieth, W. Electrochim. Acta 2005, 51, 1117. ... 26) Vu, QT; Pavlik, M.; Hebestreit, N.; Rammelt, U.; Plieth, W.; Pfleger, J. React. Funct. Polym. 2005, 65, 69. ...
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