A novel mechanism of proton transfer in protonated peptides
Language English Country United States Media print
Document type Journal Article, Research Support, Non-U.S. Gov't
PubMed
14599203
DOI
10.1021/ja035800z
Knihovny.cz E-resources
- MeSH
- Glycine analogs & derivatives chemistry MeSH
- Protein Conformation MeSH
- Peptides chemistry MeSH
- Protons MeSH
- Thermodynamics MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Names of Substances
- Glycine MeSH
- N-acetylglycyl-N'-methylglycinamide MeSH Browser
- Peptides MeSH
- Protons MeSH
The study presents quantum-chemical calculations on proton transfer in protonated N-acetylglycyl-N1-methylglycinamide (AGA) as a short oligopeptide model. All calculations employ the B3LYP functional and the 6-31++G** basis set. Two different mechanisms of proton transfer are discussed. The rate-determining step of the first mechanism exhibits an energy barrier of about 17.7 kcal mol-1, and it is represented by an isomerization of the proton around the double bond of the carbonyl group. The second mechanism is based on the large conformational flexibility of AGA, where all carbonyl oxygens cooperate. The rate-determining step of this mechanism exhibits an energy barrier of only 8.3 kcal mol-1.
References provided by Crossref.org
Influence of stereochemistry on proton transfer in protonated tripeptide models
