Low mass MS/MS fragments of protonated amino acids used for distinction of their 13C-isotopomers in metabolic studies.

ABSTRACT: Glu, Gln, Pro, and Ala are the main amino acids involved in ammonia detoxification in mosquitoes. In order to develop a tandem mass spectrometry method (MS(2)) to monitor each carbon of the above isotopically-labeled (13)C-amino acids for metabolic studies, the compositions and origins of atoms in fragments of the protonated amino acid should be first elucidated. Thus, various electrospray (ESI)-based MS(2) tools were employed to study the fragmentation of these unlabeled and isotopically-labeled amino acids and better understand their dissociation pathways. A broad range of fragments, including previously-undescribed low m/z fragments was revealed. The formulae of the fragments (from m/z 130 down to m/z 27) were confirmed by their accurate masses. The structures and conformations of the l

SUBMITTER: Ma X 

PROVIDER: S-EPMC3624025 | biostudies-literature | 2013 Apr

REPOSITORIES: biostudies-literature