Document Detail


Competitive formation of b2 and c 2-H 2O ions from b 3 ions containing Asp residue during tandem mass spectrometry: the influence of neighboring Arg.
MedLine Citation:
PMID:  24788991     Owner:  NLM     Status:  Publisher    
Abstract/OtherAbstract:
The fragmentation of b3 ions derived from protonated Arg-Xxx-Asp-Ala-Ala (Xxx = Ala, Asp, Glu, Cys) and Arg-Xxx-Glu-Ala-Ala was investigated by electrospray ionization tandem mass spectrometry (MS (n) ) with collision-induced dissociation. A particular ion, which is 1 Da less than b2 ion, is shown to be the c2-H2O ion. The mechanism for its formation involved the aspartic acid in the third position easily losing anhydride to form a c2 ion, which then lost water to form an eight-membered ring of azacyclooctane derivative under the participation of the guanidine of the N-terminal arginine. However, this phenomenon was not observed when the aspartic acid was replaced by glutamic acid. The Amber program was used to determine the conformation of the original c2 residue from the dynamic energy perspective, and then density functional theory-based calculations and changing N-terminal amino acid from arginine to phenylalanine supported this mechanism.
Authors:
Mengzhe Guo; Cheng Guo; Yuanjiang Pan
Publication Detail:
Type:  JOURNAL ARTICLE     Date:  2014-5-1
Journal Detail:
Title:  Amino acids     Volume:  -     ISSN:  1438-2199     ISO Abbreviation:  Amino Acids     Publication Date:  2014 May 
Date Detail:
Created Date:  2014-5-2     Completed Date:  -     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  9200312     Medline TA:  Amino Acids     Country:  -    
Other Details:
Languages:  ENG     Pagination:  -     Citation Subset:  -    
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Fatty acid metabolic enzyme acyl-CoA thioesterase 8 promotes the development of hepatocellular carci...
Next Document:  Clinically Apparent and Occult Metastasized Seminoma: Almost Indistinguishable on the Transcriptiona...