1vpw is a 2 chain structure with sequence from Escherichia coli. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
The crystal structure of the purine repressor mutant L54M bound to hypoxanthine and to the purF operator provides a stereochemical understanding of the high DNA affinity of this hinge helix mutant. Comparison of the PurR L54M-DNA complex to that of the wild type PurR-DNA complex reveals that these purine repressors bind and kink DNA similarly despite significant differences in their minor groove contacts and routes to interdigitation of the central C.G:G.C base pair step. Modeling studies, supported by genetic and biochemical data, show that the stereochemistry of the backbone atoms of the abutting hinge helices combined with the rigidity of the kinked base pair step constrain the interdigitating residue to leucine or methionine for the LacI/GalR family of transcription regulators.
The structure of PurR mutant L54M shows an alternative route to DNA kinking.,Arvidson DN, Lu F, Faber C, Zalkin H, Brennan RG Nat Struct Biol. 1998 Jun;5(6):436-41. PMID:9628480[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
↑ Arvidson DN, Lu F, Faber C, Zalkin H, Brennan RG. The structure of PurR mutant L54M shows an alternative route to DNA kinking. Nat Struct Biol. 1998 Jun;5(6):436-41. PMID:9628480