Dear all,
I'm searching for examples of crystal structures that show a clear asymmetry in the dimeric/oligomeric state. This asymmetry should not have been induced by the crystal packing (e.g. two domains connected by a long linker packing different, termini/loops which interact differently with the surrounding) rather than by an internal asymmetry (which may be confirmed by other techniques e.g. SAXS).
The reason I'm asking: I have solved a couple of crystal structures of a chimera protein (110 residues, dimeric, 1.2 A resolution) and mutants of the same fragment consisting of basically two four helix bundles and a short connector fragment and these are highly asymmetric (although the H-bond pattern of the helix residues doesn't change) while the same structures solved by NMR are symmetric and largely different. PISA gives a variety of contacts (H-bonds, salt bridges) between the two chains, interface seems ok, stable, low B-factors).
Any comments and suggestions are appreciated
Best wishes and thanks!
Kornelius
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Kornelius Zeth
Max Planck Institute for Developmental Biology
Dept. Protein Evolution
Spemannstr. 35
72076 Tuebingen, Germany
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Tel -49 7071 601 323
Fax -49 7071 601 349
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