András Kocsor1, Attila Kertész-Farkas, László Kaján, Sándor Pongor. 1. Research Group on Artificial Intelligence of the Hungarian Academy of Sciences and University of Szeged Aradi vértanúk tere 1., H-6720 Szeged, Hungary. kocsor@inf.u-szeged.hu
Abstract
MOTIVATION: Distance measures built on the notion of text compression have been used for the comparison and classification of entire genomes and mitochondrial genomes. The present study was undertaken in order to explore their utility in the classification of protein sequences. RESULTS: We constructed compression-based distance measures (CBMs) using the Lempel-Zlv and the PPMZ compression algorithms and compared their performance with that of the Smith-Waterman algorithm and BLAST, using nearest neighbour or support vector machine classification schemes. The datasets included a subset of the SCOP protein structure database to test distant protein similarities, a 3-phosphoglycerate-kinase sequences selected from archaean, bacterial and eukaryotic species as well as low and high-complexity sequence segments of the human proteome, CBMs values show a dependence on the length and the complexity of the sequences compared. In classification tasks CBMs performed especially well on distantly related proteins where the performance of a combined measure, constructed from a CBM and a BLAST score, approached or even slightly exceeded that of the Smith-Waterman algorithm and two hidden Markov model-based algorithms.
MOTIVATION: Distance measures built on the notion of text compression have been used for the comparison and classification of entire genomes and mitochondrial genomes. The present study was undertaken in order to explore their utility in the classification of protein sequences. RESULTS: We constructed compression-based distance measures (CBMs) using the Lempel-Zlv and the PPMZ compression algorithms and compared their performance with that of the Smith-Waterman algorithm and BLAST, using nearest neighbour or support vector machine classification schemes. The datasets included a subset of the SCOP protein structure database to test distant protein similarities, a 3-phosphoglycerate-kinase sequences selected from archaean, bacterial and eukaryotic species as well as low and high-complexity sequence segments of the human proteome, CBMs values show a dependence on the length and the complexity of the sequences compared. In classification tasks CBMs performed especially well on distantly related proteins where the performance of a combined measure, constructed from a CBM and a BLAST score, approached or even slightly exceeded that of the Smith-Waterman algorithm and two hidden Markov model-based algorithms.
Authors: Paolo Sonego; Mircea Pacurar; Somdutta Dhir; Attila Kertész-Farkas; András Kocsor; Zoltán Gáspári; Jack A M Leunissen; Sándor Pongor Journal: Nucleic Acids Res Date: 2006-11-16 Impact factor: 16.971
Authors: Daniel Barthel; Jonathan D Hirst; Jacek Błazewicz; Edmund K Burke; Natalio Krasnogor Journal: BMC Bioinformatics Date: 2007-10-26 Impact factor: 3.169