|
Title
|
|
|
|
A model-based method for the prediction of the isotopic distribution of peptides
|
|
|
Author
|
|
|
|
|
|
|
Abstract
|
|
|
|
| The process of monoisotopic mass determination, i.e., nomination of the correct peak of an isotopically resolved group of peptide peaks as a monoisotopic peak, requires prior information about the isotopic distribution of the peptide. This points immediately to the difficulty of monoisotopic mass determination, whereas a single mass spectrum does not contain information about the atomic composition of a peptide and therefore the isotopic distribution of the peptide remains unknown. To solve this problem a technique is required, which is able to estimate the isotopic distribution given the information of a single mass spectrum. Senko et al. calculated the average isotopic distribution for any mass peptide via the multinomial expansion (Yergey 1983) [1], using a scaled version of the average amino acid Averagine (Senko et al. 1995) [2]. Another method, introduced by Breen et al., approximates the result of the multinomial expansion by a Poisson model (Breen et al. 2000) [3]. Although both methods perform well, they have their specific limitations. In this manuscript, we propose an alternative method for the prediction of the isotopic distribution based on a model for consecutive ratios of peaks from the isotopic distribution, similar in spirit to the approach introduced by Gay et al. (1999) [5]. The presented method is computationally simple and accurate in predicting the expected isotopic distribution. Further, we extend our method to estimate the isotopic distribution of sulphur-containing peptides. This is important because the naturally occurring isotopes of sulphur have an impact on the isotopic distribution of a peptide. |
|
|
|
Language
|
|
|
|
English
|
|
|
Source (journal)
|
|
|
|
Journal of the American Society for Mass Spectrometry. - New York, N.Y.
|
|
|
Publication
|
|
|
|
New York, N.Y.
:
2008
|
|
|
ISSN
|
|
|
|
1044-0305
[print]
1879-1123
[online]
|
|
|
DOI
|
|
|
|
10.1016/J.JASMS.2008.01.009
|
|
|
Volume/pages
|
|
|
|
19
:5
(2008)
, p. 703-712
|
|
|
ISI
|
|
|
|
000255722200010
|
|
|
Full text (Publisher's DOI)
|
|
|
|
|
|
|
Full text (publisher's version - intranet only)
|
|
|
|
|
|