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001-es BibID:	bibKLT00007038
Első szerző:	Matter, Hans
Cím:	Structure and dynamics of a peptidoglycan monomer in aqueous solution using NMR spectroscopy and simulated annealing calculations / Hans Matter, László Szilágyi, Péter Forgó, Zeljko Marinic, Branimir Klaic
Dátum:	1997
ISSN:	0002-7863 1520-5126
Megjegyzések:	The conformation of the peptidoglycan monomer (PGM) from Brevibacterium divaricatum was determined in aqueous solution using a combined approach by 2D NMR spectroscopy, restrained simulated annealing, and molecular dynamics (MD) calculations. MD simulations in water without experimental constraints provided insights into the structure and dynamics of this glycopeptide. Hierarchical cluster analyses for conformer classifications were performed using a global molecular shape descriptor (CoMFA steric fields). Principal component analysis was subsequently employed to extract orthogonal principal conformational properties. Correlated dihedral angle mobilities were identified using a dynamic cross correlation map. The calculation of radial distribution functions for all polar protons of the molecule leads to additional information about the solvation of PGM in a protic solvent, while autocorrelation functions for dihedral angle fluctuations were used to monitor dynamic processes in different regions. From simulated annealing, a set of 11 conformers was obtained, all characterized by a well-defined extended N-terminal peptide part additionally stabilized by the bound disaccharide; the C-terminal part, on the other hand, exhibits more conformational flexibility in agreement with experimental data and MD simulations. The disaccharide conformation is in agreement with the conformational minimum computed for the model disaccharide 3-O-Me-4-O-βGlcNAc-αMurNAc using various force fields. Not only the interglycosidic bond but also the glycopeptide linkage exists in a single, well-defined conformation, for which no conformational changes can be detected during the MD simulations. In contrast, conflicting experimental data for the N-acetyl group of GlcNAc could be explained using a conformer population analysis based on ROE intensities and coupling constants accounting for a conformational equilibrium with one dominantly populated rotamer.
Tárgyszavak:	Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
Megjelenés:	Journal of the American Chemical Society. - 119 : 9 (1997), p. 2212-2223. -
További szerzők:	Szilágyi László (1941-) (vegyész) Forgó Péter Marinic, Željko Klaić, Branimir
Internet cím:	DOI
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001-es BibID:	KLTEbibl004567
Első szerző:	Szilágyi László (vegyész)
Cím:	Determination of proton-proton distances in 2-acetamido-2-deoxy monosaccharides from 1H NMR relaxation measurements in solution / László Szilágyi, Péter Forgó
Dátum:	1993
ISSN:	0008-6215 1873-426X
Megjegyzések:	Determination of selective and biselective 1H spin-lattice relaxation rates combined with steady-state and transient 1H1H NOE data allowed calculation of intramolecular proton-proton distances in 2-acetamido-2-deoxy-d-glucosides (1a an 1b), 2-acetamido-2-deoxy-d-mannoses (5a and 5b) and their acetylated derivatives. These measurements were supplemented by DESERT studies using derivatives selectively labeled by 2H at position 2. These distance data are in good correlation with literature values obtained by X-ray crystallography. Interproton distance measurements allow the determination of relative configurations, including that of the anomeric carbon, in hexopyranose rings in cases where other methods, like those based on scalar coupling constants, fail.
Tárgyszavak:	Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
Megjelenés:	Carbohydrate Research. - 247 (1993), p. 129-144. -
További szerzők:	Forgó Péter
Internet cím:	Intézményi repozitóriumban (DEA) tárolt változat DOI
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