Science (American Association for the Advancement of Science), 2001-10, Vol.294 (5541), p.369-374
2001
Volltextzugriff (PDF)
Details
- Autor(en) / Beteiligte
- Titel
- Observation of Covalent Intermediates in an Enzyme Mechanism at Atomic Resolution
- Ist Teil von
- Science (American Association for the Advancement of Science), 2001-10, Vol.294 (5541), p.369-374
- Ort / Verlag
- Washington, DC: American Society for the Advancement of Science
- Erscheinungsjahr
- 2001
- Quelle
- American Association for the Advancement of Science
- Beschreibungen/Notizen
- In classical enzymology, intermediates and transition states in a catalytic mechanism are usually inferred from a series of biochemical experiments. Here, we derive an enzyme mechanism from true atomic-resolution x-ray structures of reaction intermediates. Two ultra-high resolution structures of wild-type and mutant D-2-deoxyribose-5-phosphate (DRP) aldolase complexes with DRP at 1.05 and 1.10 angstroms unambiguously identify the postulated covalent carbinolamine and Schiff base intermediates in the aldolase mechanism. In combination with site-directed mutagenesis and1Hnuclear magnetic resonance, we can now propose how the heretofore elusive C-2 proton abstraction step and the overall stereochemical course are accomplished. A proton relay system appears to activate a conserved active-site water that functions as the critical mediator for proton transfer.
- Sprache
- Englisch
- Identifikatoren
- ISSN: 0036-8075eISSN: 1095-9203DOI: 10.1126/science.1063601Titel-ID: cdi_proquest_miscellaneous_743105673
- Format
- –
- Schlagworte
- Active sites, Aldehyde-Lyases - chemistry, Aldehyde-Lyases - genetics, Aldehyde-Lyases - metabolism, Aldehydes, Amino Acid Substitution, Analysis, Analytical, structural and metabolic biochemistry, Atoms, Atoms & subatomic particles, Binding Sites, Biological and medical sciences, Catalysis, Cells, Chemical bases, Chemical Phenomena, Chemistry, Physical, Crystalline structure, Crystallization, Crystallography, X-Ray, Electron density, Enzyme kinetics, Enzymes, Enzymes and enzyme inhibitors, Escherichia coli - enzymology, Fundamental and applied biological sciences. Psychology, Hydrogen Bonding, Hydrogen-Ion Concentration, Ligands, Lyases, Lysine - chemistry, Models, Chemical, Molecular biophysics, Molecules, Mutagenesis, Site-Directed, Mutation, Nuclear Magnetic Resonance, Biomolecular, Nuclear research, Protein Conformation, Protein Folding, Protein Structure, Tertiary, Protons, Ribosemonophosphates - chemistry, Ribosemonophosphates - metabolism, Schiff Bases, Structure in molecular biology, Studies, Water, X-rays