Reconstruction of amino acid sequence of cyclic peptides from mass spectra

Abstract

The method of mass spectrometry is one of physical methods of proteome study in different organisms; it allows us to solve both problems of biological macromolecule identification and sequencing of peptide chains in cases in the absence of or limited information about genomes. At present, there are many computer programs for supporting the studies in this field. Nevertheless, in spite of the high activity, there is only insignificant progress in creating programs allowing us to solve problems of de novo sequencing for cyclic peptides, which include the most efficient antibiotics, antitumor agents, immunosuppressants, toxins, and many peptides with unknown functions synthesized in the cell by a nonribosomal pathway. An efficient algorithm for solving the problem of cyclic peptide sequencing, which allows us to restore sequences of large length of up to 160 amino acid residues, was suggested.