Progressive multiple alignment using sequence triplet optimizations and three-residue exchange costs.

Arun Siddharth Konagurthu; James Whisstock; Peter J Stuckey

doi:10.1142/s0219720004000831

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Progressive multiple alignment using sequence triplet optimizations and three-residue exchange costs.

Arun Siddharth Konagurthu·James Whisstock·Peter J Stuckey

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Abstract

In this paper we demonstrate a practical approach to construct progressive multiple alignments using sequence triplet optimizations rather than a conventional pairwise approach. Using the sequence triplet alignments progressively provides a scope for the synthesis of a three-residue exchange amino acid substitution matrix. We develop such a 20 x 20 x 20 matrix for the first time and demonstrate how its use in optimal sequence triplet alignments increases the sensitivity of building multiple alignments. Various comparisons were made between alignments generated using the progressive triplet methods and the conventional progressive pairwise procedure. The assessment of these data reveal that, in general, the triplet based approaches generate more accurate sequence alignments than the traditional pairwise based procedures, especially between more divergent sets of sequences.

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Algorithms Amino Acid Sequence Amino Acids Models, Chemical Models, Molecular Models, Statistical Molecular Sequence Data Protein Conformation Proteins Sequence Alignment Sequence Analysis, Protein Evaluation Study Journal Article

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Arun Siddharth Konagurthu, James Whisstock, Peter J Stuckey. 2004. Progressive multiple alignment using sequence triplet optimizations and three-residue exchange costs.. https://doi.org/10.1142/s0219720004000831

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