Performance Evaluation of Existing De Novo Sequencing Algorithms

Department of Mathematical Cybernetics, Lomonosov Moscow State University, Moskva, Moscow, Russia
Journal of Proteome Research (Impact Factor: 4.25). 11/2006; 5(11):3018-28. DOI: 10.1021/pr060222h
Source: PubMed


Two methods have been developed for protein identification from tandem mass spectra: database searching and de novo sequencing. De novo sequencing identifies peptide directly from tandem mass spectra. Among many proposed algorithms, we evaluated the performance of the five de novo sequencing algorithms, AUDENS, Lutefisk, NovoHMM, PepNovo, and PEAKS. Our evaluation methods are based on calculation of relative sequence distance (RSD), algorithm sensitivity, and spectrum quality. We found that de novo sequencing algorithms have different performance in analyzing QSTAR and LCQ mass spectrometer data, but in general, perform better in analyzing QSTAR data than LCQ data. For the QSTAR data, the performance order of the five algorithms is PEAKS > Lutefisk, PepNovo > AUDENS, NovoHMM. The performance of PEAKS, Lutefisk, and PepNovo strongly depends on the spectrum quality and increases with an increase of spectrum quality. However, AUDENS and NovoHMM are not sensitive to the spectrum quality. Compared with other four algorithms, PEAKS has the best sensitivity and also has the best performance in the entire range of spectrum quality. For the LCQ data, the performance order is NovoHMM > PepNovo, PEAKS > Lutefisk > AUDENS. NovoHMM has the best sensitivity, and its performance is the best in the entire range of spectrum quality. But the overall performance of NovoHMM is not significantly different from the performance of PEAKS and PepNovo. AUDENS does not give a good performance in analyzing either QSTAR and LCQ data.

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Available from: Irina Fedulova
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    • "With the advancement of mass spectrometry technology and appearance of novel computational methods, de novo algorithm has been greatly improved. However, it is still not comparable with database-searching for common protein identification and needs manual checks by proteomics experts, which is time consuming and of low-throughput (Pevtsov et al., 2006; Kim et al., 2009a). In this study, we exploited the predominance of de novo peptide sequencing to identify SAV-peptides, and used mature database-searching strategy to monitor false discovery. "
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    • "A possible alternative is using de novo sequencing, in which amino acid sequences are deduced directly from fragmentation spectra, without the need for a protein DB, followed by BLAST search for identification of candidate homologous proteins [24], [25]. However, manual inspection of spectra is often required due to the error-prone nature of de novo sequencing, and very high quality data are necessary for achieving reliable results [26]. "
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