Wyniki wyszukiwania - Biblioteka Nauki

1

Evaluation of high temperature glycation of proteins and peptides by electrospray ionization mass spectrometry.

100%

Stefanowicz P. , Boratyński J. , Kańska U. , Petry I. , Szewczuk Z.

Acta Biochimica Polonica

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2001

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tom 48

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nr 4

1137-1141

EN

Recently Boratyński & Roy (Glycoconjugate J., 1998, 15, 131) described a fast and convenient procedure for the synthesis of glycoconjugates. In the present study we used ESI-MS and circular dichroism as tools to analyze non-enzymatic glycation prod- ucts of proteins and peptides. We discuss influence of reaction conditions on the rate of glycation of lysozyme. We analyze for the first time collision induced dissociation spectra of the obtained peptide conjugates.

2

Conformational stability of six truncated cHMG1a proteins studied in their mixture by H/D exchange and electrospray ionization mass spectrometry.

100%

Petry I. , Wiśniewski J. R. , Szewczuk Z.

Acta Biochimica Polonica

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2001

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tom 48

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nr 4

1131-1136

EN

The high mobility group (HMG) proteins are abundant non-histone components of eukaryotic chromatin. The presence of C-terminal acidic tails is a common feature of the majority of HMG proteins. Although the biological significance of the acidic domains is not clear, they are conferring conformational and metabolic stability to the proteins in vitro. Moreover, the length and net charge of the acidic tails affect the strength of HMG protein interaction with DNA. Synthesis of an insect HMG protein by standard recombinant technology in bacteria leads to a mixture of the intact protein (cHMG1a-(1-113) (I)) and a series of its degradation products truncated at the C tail: cHMG1a-(1-111) (II); cHMG1a-(1-110) (III); cHMG1a-(1-109) (IV); cHMG1a-(1-108) (V); cHMG1a-(1-107) (VI); cHMG1a-(1-106) (VII). The proteins differ from each other only by the number of amino-acid residues at the C-terminal tail. We used H/D exchange mass spectrometry to characterize the stability of the proteins directly in their mixture. The results show that the proteins I-V and VII have very similar conformations. The protein VI is less compact and exchanges its protons faster than the others. It may be concluded that the C-terminal tail influences the conformation of the cHMG1a protein and that individual residues in this part of the protein play a key role in its compactness.

3

Synthesis and Determination of Alkali Metal Binding Selectivities of Chiral Macrocyclic Bissulfonamides Derived from D-Mannitol and L-Threitol

75%

Gruza M. , Pokrop A. , Jurczak J.

Polish Journal of Chemistry

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2005

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tom Vol. 79 / nr 2

223-230

EN

Four chiral macrocyclic bissulfonamides derived from D-mannitol and L-threitol, possessing C2 symmetry, were obtained by a macrocyclization reaction under high-dilution conditions. Their applications for alkali metal binding processes were studied using ESI-MS technique.

4

Crystal structure and spectroscopic properties of 4-acetaminopyridine and its protonated form

51%

Koleva B. B. , Nikolova R. , Tchapkanov A. , Kolev T. , Mayer-Figge H. , Spiteller M. , Sheldrick W. S.

Polish Journal of Chemical Technology

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2009

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tom Vol. 11, nr 3

35-40

EN

4-Acetaminopyridine dihydrate and its protonated form, stabilized as the hydrochloride salt have been synthesized and spectroscopic elucidated in solution and in the solid-state by means of the inear-polarized solid state IR-spectroscopy (IR-LD), UV-spectroscopy, TGA, DSC, and the positive and negative ESI MS. Quantum chemical calculations were used to obtain the electronic structure, vibrational data and the electronic spectra. The spectroscopic and theoretical data are compared with the structure of the first compound obtained by single crystal X-ray diffraction. The effect of Npy protonation on the optical and magnetic properties of a 4-acetaminopyridine is discussed.

5

Structural Elucidation, Optical and Magnetic Properties of Tetraphenylborate Salt of 2,5-[1-Methyl-4-[2-(4-hydroxyphenyl)ethenyl)]pyridinium]-butane

51%

Stoyanov S. , Koleva B. B. , Kolev T. , Petkov I. , Spiteller M.

Polish Journal of Chemistry

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2008

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tom Vol. 82, nr 11

2167-2178

EN

Structure, magnetic and optical properties of tetraphenylborate salt of 2,5-[1-methyl-4-[2-(4-hydroxyphenyl)ethenyl)]pyridinium]-hexane were performed for condensed phase by means of solution and solid-state conventional and linear-polarized IR-spectroscopy of oriented colloids in nematic host, UV-Vis and fluorescence methods, HPLC MS-MS tandem and ESI mass spectrometry, 1H-, 13C- and 1H-1H COSY NMR, TGV and DSC methods. Electronic structure and vibrational analysis were carried out by quantum chemical calculations at two levels of theory second-order Moller-Plesset perturbation theory (MP2) and density functional theory (DFT) using 6-31G* basis set. B3LYP method, which combines Becke's three-parameter non-local exchange functional with the correlation function of Lee, Yang and Parr, was applied.

6

Badania potencjometryczne, ESI-MS i NMR nad kompleksowaniem magnezu(II) i wapnia(II) wybranymi kwasami bisfosfonowymi w roztworze wodnym

51%

Szpak M. , Matczak-Jon E. , Kurzak B.

Chemik

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2014

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tom Vol. 68, nr 4

321--328

PL

Przeprowadzono badania nad równowagami w roztworze układów Mg(II)/Ca(II)-L (L= kwas (cykloheksylo)aminometano-1,1-difosfonowy (1), kwas azepan-1-ylo-metano-1,1-difosfonowy (2), kwas azekan-1-ylo-metano-1,1-difosfonowy (3)) metodami pH-potencjometrii, NMR i ESI-MS. Uzyskane wyniki wskazują, że we wszystkich badanych układach preferowane jest tworzenie kompleksów jednordzeniowych o stechiometrii 1:1. Rozpatrywane związki wiążą koordynacyjnie Mg(II) i Ca(II) poprzez atomy tlenu grup fosfonianowych w szerokim zakresie wartości pH.

EN

Solution equilibrium studies on the Mg(II)/Ca(II)-L systems (L= (cyclohexyl)aminomethane-1,1-diphosphonic acid (1), azepan-1-yl-methane-1,1-diphosphonic acid (2), azecan-1-yl-methane-1,1-diphosphonic acid (3) have been performed by pH-potentiometry, NMR and ESI-MS methods. The obtained results suggest preference for the formation of mononuclear complexes of 1:1 stoichiometry in all studied systems. Compounds under consideration coordinate Mg(II) and Ca(II) through oxygen atoms of the phosphonate groups over a broad pH range.