Janes R W, Peapus D H, Wallace B A
Department of Crystallography, Birkbeck College, University of London, UK.
Nat Struct Biol. 1994 May;1(5):311-9. doi: 10.1038/nsb0594-311.
The three-dimensional structure of the vasoactive polypeptide endothelin, the most potent vasoconstrictor yet identified, has been determined by X-ray crystallography to 2.18 A resolution. This intermediate-sized structure was solved by molecular replacement techniques using a fragment of an NMR-derived model for initial phasing of the data. However, comparisons of the final X-ray structure with the many diverse models derived from NMR data indicate some important differences, especially in the carboxy-terminal region of the molecule: the entire carboxy terminal tail (residues 16-21) is helical in the crystal structure, but not in any of the NMR structures. This may be a functionally significant difference as this region is crucial for receptor binding and vasoactivity.
