title: The phage 434 Cro/OR1 complex at 2.5 A resolution.
abstract: The crystal structure of phage 434 Cro protein in complex with a 20 base-pair DNA fragment has been determined to 2.5 A resolution. The DNA fragment contains the sequence of the OR1 operator site. The structure shows a bent conformation for the DNA, straighter at the center and more bent at the ends. The central base-pairs adopt conformations with significant deviations from coplanarity. The two molecules interact extensively along their common interface, both through hydrogen bonds and van der Waals interactions. The significance of these interactions for operator binding and recognition is discussed.
authors.affiliation: Department of Biochemistry and Molecular Biology, Harvard University, Cambridge, MA 02138.
authors.forename: A
authors.initials: A
authors.lastname: Mondragón
authors.forename: S C
authors.initials: SC
authors.lastname: Harrison
mesh_terms: D000595:Amino Acid Sequence; D001435:Bacteriophages / Q000032:analysis / Q000235:genetics; D001482:Base Composition; D001483:Base Sequence; D004279:DNA, Viral / Q000737:chemistry / Q000378:metabolism*; D004268:DNA-Binding Proteins; D005814:Genes, Viral; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D011487:Protein Conformation; D012097:Repressor Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D014764:Viral Proteins; D054334:Viral Regulatory and Accessory Proteins; D014961:X-Ray Diffraction / Q000379:methods
chemical_list: D004279:DNA, Viral; D004268:DNA-Binding Proteins; D012097:Repressor Proteins; D014764:Viral Proteins; D054334:Viral Regulatory and Accessory Proteins; C016649:phage repressor proteins