1utb: Difference between revisions

The transcriptional regulator DntR, a member of the LysR family, is a, central element in a prototype bacterial cell-based biosensor for the, detection of hazardous contamination of soil and groundwater by, dinitrotoluenes. To optimise the sensitivity of the biosensor for such, compounds we have chosen a rational design of the inducer-binding cavity, based on knowledge of the three-dimensional structure of DntR. We report, two crystal structures of DntR with acetate (resolution 2.6 angstroms) and, thiocyanate (resolution 2.3 angstroms), respectively, occupying the, inducer-binding cavity. These structures allow for the construction of, models of DntR in complex with salicylate (Kd approximately or = 4 microM), and 2,4-dinitrotoluene that provide a basis for the design of mutant DntR, with enhanced specificity for dinitrotoluenes. In both crystal structures, DntR crystallises as a homodimer with a "head-to-tail" arrangement of, monomers in the asymmetric unit. Analysis of the crystal structure has, allowed the building of a full-length model of DntR in its biologically, active homotetrameric form consisting of two "head-to-head" dimers. The, implications of this model for the mechanism of transcription regulation, by LysR proteins are discussed.

1UTB is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Burkholderia_sp. Burkholderia sp.] with ACT and GOL as [http://en.wikipedia.org/wiki/ligands ligands]. Structure known Active Site: AC1. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=1UTB OCA].  

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