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1s7z
From Proteopedia
Structure of Ocr from Bacteriophage T7
Overview
We have solved, by X-ray crystallography to a resolution of 1.8 A, the structure of a protein capable of mimicking approximately 20 base pairs of B-form DNA. This ocr protein, encoded by gene 0.3 of bacteriophage T7, mimics the size and shape of a bent DNA molecule and the arrangement of negative charges along the phosphate backbone of B-form DNA. We also demonstrate that ocr is an efficient inhibitor in vivo of all known families of the complex type I DNA restriction enzymes. Using atomic force microscopy, we have also observed that type I enzymes induce a bend in DNA of similar magnitude to the bend in the ocr molecule. This first structure of an antirestriction protein demonstrates the construction of structural mimetics of long segments of B-form DNA.
About this Structure
1S7Z is a Single protein structure of sequence from Enterobacteria phage t7. Full crystallographic information is available from OCA.
Reference
Structure of Ocr from bacteriophage T7, a protein that mimics B-form DNA., Walkinshaw MD, Taylor P, Sturrock SS, Atanasiu C, Berge T, Henderson RM, Edwardson JM, Dryden DT, Mol Cell. 2002 Jan;9(1):187-94. PMID:11804597 Page seeded by OCA on Sat May 3 08:24:45 2008
