| Formation of [b3 - 1 + cat]+ ions from metal-cationized tetrapeptides containing beta-alanine, gamma-aminobutyric acid or epsilon-aminocaproic acid residues. | |
| | |
MedLine Citation:
|
PMID: 18449851 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
|
The presence and position of a single beta-alanine (betaA), gamma-aminobutyric acid (gammaABu) or epsilon-aminocaproic acid (Cap) residue has been shown to have a significant influence on the formation of b(n)+ and y(n)+ product ions from a series of model, protonated peptides. In this study, we examined the effect of the same residues on the formation of analogous [b3 - 1 + cat]+ products from metal (Li+, Na+ and Ag+)-cationized peptides. The larger amino acids suppress formation of b3+ from protonated peptides with general sequence AAXG (where X = beta-alanine, gamma-aminobutyric acid or epsilon-aminocaproic acid), presumably because of the prohibitive effect of larger cyclic intermediates in the 'oxazolone' pathway. However, abundant [b3 - 1 + cat]+ products are generated from metal-cationized versions of AAXG. Using a group of deuterium-labeled and exchanged peptides, we found that formation of [b3 - 1 + cat]+ involves transfer of either amide or alpha-carbon position H atoms, and the tendency to transfer the atom from the alpha-carbon position increases with the size of the amino acid in position X. To account for the transfer of the H atom, a mechanism involving formation of a ketene product as [b3 - 1 + cat]+ is proposed. |
| | |
Authors:
|
Sandra M Osburn; Sila O Ochola; Erach R Talaty; Michael J Van Stipdonk |
Publication Detail:
|
Type: Journal Article; Research Support, Non-U.S. Gov't; Research Support, U.S. Gov't, Non-P.H.S. |
Journal Detail:
|
Title: Journal of mass spectrometry : JMS Volume: 43 ISSN: 1076-5174 ISO Abbreviation: J Mass Spectrom Publication Date: 2008 Nov |
Date Detail:
|
Created Date: 2008-10-29 Completed Date: 2009-01-08 Revised Date: - |
Medline Journal Info:
|
Nlm Unique ID: 9504818 Medline TA: J Mass Spectrom Country: England |
Other Details:
|
Languages: eng Pagination: 1458-69 Citation Subset: IM |
Affiliation:
|
Department of Chemistry, Wichita State University, 1845 Fairmount, Wichita, KS 67260-0051, USA. |
Export Citation:
|
APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
|
6-Aminocaproic Acid
/
chemistry* Cations Ions Metals / chemistry* Peptides / chemistry* Spectrometry, Mass, Electrospray Ionization / methods* beta-Alanine / chemistry* gamma-Aminobutyric Acid / chemistry* |
| Chemical | |
Reg. No./Substance:
|
0/Cations; 0/Ions; 0/Metals; 0/Peptides; 107-95-9/beta-Alanine; 56-12-2/gamma-Aminobutyric Acid; 60-32-2/6-Aminocaproic Acid |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
Previous Document: Polydrug use, cannabis, and psychosis-like symptoms.
Next Document: Effects of metabolic inhibitors on activity of Cry1Ab toxin to inhibit growth of Ephestia kuehniella...