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4cro
From Proteopedia
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PROTEIN-DNA CONFORMATIONAL CHANGES IN THE CRYSTAL STRUCTURE OF A LAMBDA CRO-OPERATOR COMPLEX
Overview
The structure of a complex of bacteriophage lambda Cro protein with a, 17-base-pair operator has been determined at 3.9-A resolution. Isomorphous, derivatives obtained by the synthesis of site-specific iodinated DNA, oligomers were of critical importance in solving the structure. The, crystal structure contains three independent Cro-operator complexes that, have very similar, although not necessarily identical, conformations. In, the complex, the protein dimer undergoes a large conformational change, relative to the crystal structure of the free protein. One monomer rotates, by about 40 degrees relative to the other, this being accomplished, primarily by a twisting of the two beta-sheet strands that connect one, monomer with the other. In the complex, the DNA is bent by about 40, degrees into the shape of a boomerang but maintains essentially, Watson-Crick B-form. In contrast to other known protein-DNA complexes, the, DNA is not stacked end-to-end. The structure confirms the general features, of the model previously proposed for the interaction of Cro with DNA.
About this Structure
4CRO is a Single protein structure of sequence from Enterobacteria phage lambda. Full crystallographic information is available from OCA.
Reference
Protein-DNA conformational changes in the crystal structure of a lambda Cro-operator complex., Brennan RG, Roderick SL, Takeda Y, Matthews BW, Proc Natl Acad Sci U S A. 1990 Oct;87(20):8165-9. PMID:2146682
Page seeded by OCA on Tue Nov 20 19:30:39 2007
