2UYE

Double mutant Y110S,F111V DntR from Burkholderia sp. strain DNT in complex with thiocyanate

Summary for 2UYE

• Entry DOI: 10.2210/pdb2uye/pdb
• Related: 1UTB 1UTH 2UYF
• Descriptor: REGULATORY PROTEIN, THIOCYANATE ION, GLYCEROL, ... (4 entities in total)
• Functional Keywords: lttr, lysr, dna-binding, transcription, transcription regulation, transcriptional regulator
• Biological source: Burkholderia cepacia
• Total number of polymer chains: 2
• Total formula weight: 70155.16

Authors

Lonneborg, R.,Smirova, I.,Dian, C.,leonard, G.A.,McSweeney, S.,Brzezinski, P. (deposition date: 2007-04-04, release date: 2007-08-21, Last modification date: 2023-12-13)

Primary citation

Lonneborg, R.,Smirova, I.,Dian, C.,Leonard, G.A.,Brzezinski, P.
In Vivo and in Vitro Investigation of Transcriptional Regulation by Dntr.
J.Mol.Biol., 372:571-, 2007

PubMed Abstract: DntR is a bacterial transcription factor that has been isolated from Burkholderia species that are able to degrade the nitro-aromatic compound 2,4-dinitrotoluene. We recently solved the X-ray crystal structure of DntR, which suggested a putative location of an inducer-binding cavity (IBC). In this study, we constructed mutants of DntR in which residues lining the proposed IBC were modified in order to identify the structural elements involved in inducer binding, to modulate the inducer binding specificity, and to investigate the mechanism of transcriptional regulation by DntR. The transcriptional activation of the reporter gene gfp induced by the wild-type and mutant DntRs was monitored by analysing whole-cell fluorescence using flow-cytometry after addition of a number of potential inducer compounds. Three of the mutant proteins (F111L; F111V/H169V and Y110S/F111V) were purified and the binding constants for several of the potential inducers to these mutants were estimated. Furthermore, crystal structures of the F111L and Y110S/F111V mutant proteins were solved and used to explain changes in the inducer binding specificity at an atomic level. A comparison of the inducing capability in the whole-cell system and binding constants for a number of potential inducers suggests a mechanism where binding of an inducer molecule is not the sole requirement for transcriptional activation. In addition, specific interactions between DntR and the inducer molecule resulting in a conformational change of the protein are needed.

PubMed: 17681542
DOI: 10.1016/J.JMB.2007.06.076

Experimental method

X-RAY DIFFRACTION (2.2 Å)