Sharif, S. ; Fogle, E. ; Toney, M. D. ; Denisov, G. S. ; Shenderovich, I. G. ; Buntkowsky, G. ; Tolstoy, P. M. ; Huot, M. C. ; Limbach, H. H. (2007)
NMR localization of protons in critical enzyme hydrogen bonds.
In: Journal of the American Chemical Society, 129 (31)
Artikel, Bibliographie
Kurzbeschreibung (Abstract)
Using N-15 NMR spectroscopy and hydrogen bond correlations, we have localized a mechanistically critical proton in aspartate aminotransferase in microcrystals and aqueous solution. It is in a H-bond between a carboxylate O of Asp222 and the pyridine nitrogen of pyridoxal-5'-phosphate. At neutral pH in water, aspartate and pyridine are unprotonated, but they share a proton in the enzyme. It is shown that such a binuclear base is typical for acid-base interactions in aprotic polar solvents. Active site H-bonds to Asp222 assist protonation of the pyridine nitrogen in the enzyme, which is considered a prerequisite for catalytic activity. We also show that acid-base behavior in enzymes should be modeled using aprotic polar solvents rather than aqueous solutions.
| Typ des Eintrags: | Artikel |
|---|---|
| Erschienen: | 2007 |
| Autor(en): | Sharif, S. ; Fogle, E. ; Toney, M. D. ; Denisov, G. S. ; Shenderovich, I. G. ; Buntkowsky, G. ; Tolstoy, P. M. ; Huot, M. C. ; Limbach, H. H. |
| Art des Eintrags: | Bibliographie |
| Titel: | NMR localization of protons in critical enzyme hydrogen bonds |
| Sprache: | Englisch |
| Publikationsjahr: | 2007 |
| Titel der Zeitschrift, Zeitung oder Schriftenreihe: | Journal of the American Chemical Society |
| Jahrgang/Volume einer Zeitschrift: | 129 |
| (Heft-)Nummer: | 31 |
| URL / URN: | http://apps.webofknowledge.com/full_record.do?product=WOS&se... |
| Kurzbeschreibung (Abstract): | Using N-15 NMR spectroscopy and hydrogen bond correlations, we have localized a mechanistically critical proton in aspartate aminotransferase in microcrystals and aqueous solution. It is in a H-bond between a carboxylate O of Asp222 and the pyridine nitrogen of pyridoxal-5'-phosphate. At neutral pH in water, aspartate and pyridine are unprotonated, but they share a proton in the enzyme. It is shown that such a binuclear base is typical for acid-base interactions in aprotic polar solvents. Active site H-bonds to Asp222 assist protonation of the pyridine nitrogen in the enzyme, which is considered a prerequisite for catalytic activity. We also show that acid-base behavior in enzymes should be modeled using aprotic polar solvents rather than aqueous solutions. |
| Freie Schlagworte: | coli aspartate-aminotransferase escherichia-coli carboxylic-acids 10-18-ppm range h-1 resonances concanavalin-a model systems active-site solid-state pyridoxal |
| Zusätzliche Informationen: | 196LW Times Cited:35 Cited References Count:31 |
| Fachbereich(e)/-gebiet(e): | 07 Fachbereich Chemie 07 Fachbereich Chemie > Eduard Zintl-Institut > Fachgebiet Physikalische Chemie |
| Hinterlegungsdatum: | 27 Okt 2014 20:49 |
| Letzte Änderung: | 29 Mai 2019 12:48 |
| PPN: | |
| Export: | |
| Suche nach Titel in: | TUfind oder in Google |
 |
Frage zum Eintrag |
Optionen (nur für Redakteure)
 |
Redaktionelle Details anzeigen |
Drucken
Impressum