Open AccessA novel mass spectrometric approach to the analysis of hormonal peptides in extracts of mouse pancreatic islets
Author(s) -
Ramström Margareta,
Hagman Charlotte,
Tsybin Youri O.,
Markides Karin E.,
Håkansson Per,
Salehi Albert,
Lundquist Ingmar,
Håkanson Rolf,
Bergquist Jonas
Publication year - 2003
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1046/j.1432-1033.2003.03690.x
Subject(s) - chemistry , fourier transform ion cyclotron resonance , peptide , mass spectrometry , electrospray ionization , chromatography , fragmentation (computing) , islet , peptide sequence , electron capture dissociation , biochemistry , insulin , biology , gene , ecology , endocrinology
Liquid chromatography mass spectrometry (LC‐MS) is a valuable tool in the analysis of proteins and peptides. The combination of LC‐MS with different fragmentation methods provides sequence information on components in complex mixtures. In this work, on‐line packed capillary LC electrospray ionization Fourier transform ion cyclotron resonance MS was combined with two complementary fragmentation techniques, i.e. nozzle‐skimmer fragmentation and electron capture dissociation, for the determination of hormonal peptides in an acid ethanol extract of mouse pancreatic islets. The most abundant peptides, those derived from proinsulin and proglucagon, were identified by their masses and additional sequence‐tag information established their identities. Interestingly, the experiments demonstrated the presence of truncated C‐peptides, des ‐(25–29)‐C‐peptide and des ‐(27–31)‐C‐peptide. These novel findings clearly illustrate the potential usefulness of the described technique for on‐line sequencing and characterization of peptides in tissue extracts.