Title |
Multistep tandem mass spectrometry for Sequencing Cyclic Peptides in an Ion-Trap Mass Spectrometer
|
---|---|
Published in |
Journal of the American Society for Mass Spectrometry, August 1999
|
DOI | 10.1016/s1044-0305(99)00049-5 |
Pubmed ID | |
Authors |
Lambert C. M. Ngoka, Michael L. Gross |
Abstract |
Collisionally activated decomposition (CAD) of a protonated cyclic peptide produces a superposition spectrum consisting of fragments produced following random ring opening of the cyclic peptide to give a set of acylium ions (or isomeric equivalents) of the same m/z. Assignment of the correct sequence is often difficult owing to lack of selectivity in the ring opening. A method is presented that utilizes multiple stages of CAD experiments in an electrospray ion-trap mass spectrometer to sequence cyclic peptides. A primary acylium ion is selected from the primary product-ion spectrum and subjected to several stages of CAD. Amino-acid residues are sequentially removed, one at each stage of the CAD, from the C-terminus, until a b2 ion is reached. Results are presented for seven cyclic peptides, ranging in sizes from four to eight amino-acid residues. This method of sequencing cyclic peptides eliminates ambiguities encountered with other MS/MS approaches. The power of the strategy lies in the capability to execute several stages of CAD upon a precursor ion and its decomposition products, allowing the cyclic peptide to be sequenced in an unambiguous, stepwise manner. |
Mendeley readers
Geographical breakdown
Country | Count | As % |
---|---|---|
Poland | 1 | 2% |
France | 1 | 2% |
Unknown | 39 | 95% |
Demographic breakdown
Readers by professional status | Count | As % |
---|---|---|
Student > Ph. D. Student | 13 | 32% |
Researcher | 6 | 15% |
Student > Master | 4 | 10% |
Professor | 3 | 7% |
Professor > Associate Professor | 2 | 5% |
Other | 5 | 12% |
Unknown | 8 | 20% |
Readers by discipline | Count | As % |
---|---|---|
Chemistry | 18 | 44% |
Agricultural and Biological Sciences | 9 | 22% |
Biochemistry, Genetics and Molecular Biology | 2 | 5% |
Immunology and Microbiology | 1 | 2% |
Medicine and Dentistry | 1 | 2% |
Other | 1 | 2% |
Unknown | 9 | 22% |