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K2D2: estimation of protein secondary structure from circular dichroism spectra
Carolina Perez-Iratxeta1, Miguel A Andrade-Navarro
1Ontario Genomics Innovation Centre, Ottawa Health Research Institute, 501 Smyth, Ottawa, ON, K1H 8L6, Canada. cperez-iratxeta@ohri.ca
Background:
Circular dichroism spectroscopy is a widely used technique to analyze the secondary structure of proteins in solution. Predictive methods use the circular dichroism spectra from proteins of known tertiary structure to assess the secondary structure contents of a protein with unknown structure given its circular dichroism spectrum.
Results:
We developed K2D2, a method with an associated web server to estimate protein secondary structure from circular dichroism spectra. The method uses a self-organized map of spectra from proteins with known structure to deduce a map of protein secondary structure that is used to do the predictions.
Conclusion:
The K2D2 server is publicly accessible at http://www.ogic.ca/projects/k2d2/. It accepts as input a circular dichroism spectrum and outputs the estimated secondary structure content (alpha-helix and beta-strand) of the corresponding protein, as well as an estimated measure of error.
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