High Resolution Liquid Chromatographic Mass Spectrometric Identification of Peptides Using Electrospray Ionization.
Abstract
High resolution liquid chromatography electrospray mass spectrometry (LC-ESI-MS) was investigated for the identification of known and unknown peptides in a research effort designed to evaluate the applicability of this and complementary MS techniques for the characterization and identification of peptides. The monoisotopic molecular weights of five related peptides with molecular weights between 2000 and 2500 Da, typical of bioactive peptides, were acquired with a magnetic sector resolution of 3000 (10% valley definition). Tryptic maps were generated for each peptide during high resolution LC-ESI-MS analysis and collisionally activated dissociation (CAD) in the ESI interface resulted in the production of characteristic product ions that enabled amino acid sequencing of the tryptic fragments. Under narrow and wide mass range magnetic sector scanning conditions monoisotopic molecular weight errors were typically in the 10-20 and 30-40 ppm range, respectively. Unknown identification, a critical requirement for MS methods developed in support of chemical/biological sample analysis, was demonstrated during analysis of an incomplete synthetic peptide reaction mixture. The reaction mixture for the peptide, LTTAVKKVLTTGLPALIS, was selected since the 18 amino acid target peptide was not synthesized. In its place were a number of lower molecular weight unknown peptides. The monoisotopic molecular weights of these unknowns was determined to within 10-20 ppm with a magnetic sector resolution of 3500 (10% valley definition). However, co-elution of the unknown peptides during LC-ESI-MS analysis precluded the use of CAD-MS for amino acid sequencing. Amino acid sequence information for six unknown peptides was generated by ESI-MS/MS, making use of the quadrupole collisional cell associated with the hybrid tandem mass spectrometer.
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 01, 1996
- Accession Number
- ADA322186
Entities
People
- J. R. Hancock
- Lionel Provost
- P. A. D'agostino
- P. D. Semchuk
- R. S. Hodges
Organizations
- Defence Research and Development Canada