1S7Z

Structure of Ocr from Bacteriophage T7

Summary for 1S7Z

• Entry DOI: 10.2210/pdb1s7z/pdb
• Descriptor: Gene 0.3 protein, CESIUM ION (3 entities in total)
• Functional Keywords: all helical, gene regulation
• Biological source: Enterobacteria phage T7
• Total number of polymer chains: 1
• Total formula weight: 14499.10

Authors

Walkinshaw, M.D.,Taylor, P.,Sturrock, S.S.,Atanasiu, C.,Berg, T.,Henderson, R.M.,Edwardson, J.M.,Dryden, D.T. (deposition date: 2004-01-30, release date: 2004-02-10, Last modification date: 2024-10-30)

Primary citation

Walkinshaw, M.D.,Taylor, P.,Sturrock, S.S.,Atanasiu, C.,Berg, T.,Henderson, R.M.,Edwardson, J.M.,Dryden, D.T.
Structure of Ocr from Bacteriophage T7, a Protein that Mimics B-Form DNA
Mol.Cell, 9:187-194, 2002

PubMed Abstract: 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.

PubMed: 11804597
DOI: 10.1016/S1097-2765(02)00435-5

Experimental method

X-RAY DIFFRACTION (1.83 Å)