FlexSnap: Flexible non-sequential protein structure alignment

Saeed Salem, Mohammed J. Zaki, Chris Bystroff

Research output: Contribution to journalArticle

32 Citations (Scopus)


Background: Proteins have evolved subject to energetic selection pressure for stability and flexibility. Structural similarity between proteins that have gone through conformational changes can be captured effectively if flexibility is considered. Topologically unrelated proteins that preserve secondary structure packing interactions can be detected if both flexibility and Sequential permutations are considered. We propose the FlexSnap algorithm for flexible non-topological protein structural alignment.Results: The effectiveness of FlexSnap is demonstrated by measuring the agreement of its alignments with manually curated non-sequential structural alignments. FlexSnap showed competitive results against state-of-the-art algorithms, like DALI, SARF2, MultiProt, FlexProt, and FATCAT. Moreover on the DynDom dataset, FlexSnap reported longer alignments with smaller rmsd.Conclusions: We have introduced FlexSnap, a greedy chaining algorithm that reports both sequential and non-sequential alignments and allows twists (hinges). We assessed the quality of the FlexSnap alignments by measuring its agreements with manually curated non-sequential alignments. On the FlexProt dataset, FlexSnap was competitive to state-of-the-art flexible alignment methods. Moreover, we demonstrated the benefits of introducing hinges by showing significant improvements in the alignments reported by FlexSnap for the structure pairs for which rigid alignment methods reported alignments with either low coverage or large rmsd.

Original languageEnglish
Article number12
JournalAlgorithms for Molecular Biology
Issue number1
Publication statusPublished - 4 Jan 2010
Externally publishedYes


ASJC Scopus subject areas

  • Computational Theory and Mathematics
  • Applied Mathematics
  • Molecular Biology
  • Structural Biology

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