Multi-wavelength anomalous dispersion

Multi-wavelength anomalous diffraction (sometimes Multi-wavelength anomalous dispersion; abbreviated MAD) is a technique used in X-ray crystallography that facilitates the determination of the three-dimensional structure of biological macromolecules (e.g. DNA, drug receptors) via solution of the phase problem.[1] This method doesn't need two crystal structures (one native and one with heavy atom) for a unique phase solution. Instead anomalous diffraction is recorded at different wavelengths of coherent X-ray light at a synchrotron facility.

MAD was developed by Wayne Hendrickson while working as a postdoctoral researcher under Jerome Karle at the United States Naval Research Laboratory. [2] The mathematics upon which MAD (and progenitor Single wavelength anomalous dispersion) were based were developed by Jerome Karle, work for which he was awarded the 1985 Nobel Prize in Chemistry (along with Herbert Hauptman).

See also

Anomalous Dispersion

Isomorphous Replacement

Two methods for providing the needed phasing information by introducing heavy atoms into isomorphous crystals:

Other

References

  1. Hendrickson W, Ogata C (1997). "Phase determination from multiwavelength anomalous diffraction measurements". Meth Enzymol. Methods in Enzymology 276: 494–523. doi:10.1016/S0076-6879(97)76074-9. ISBN 978-0-12-182177-7.
  2. Hendrickson WA (1985). "Analysis of Protein Structure from Diffraction Measurement at Multiple Wavelengths". Trans. ACA 21.

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Computer programs

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