2jj7
From Proteopedia
Crystal structure of the HlyIIR mutant protein with residues 170-185 substituted by alanine
Structural highlights
FunctionEvolutionary ConservationCheck, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedHlyIIR is the negative transcriptional regulator of the hemolysin II gene from Bacillus cereus. Previous X-ray studies showed that HlyIIR contains a disordered loop (a.a. 170-185) located within the C-terminal domain near dimerization interface. To understand the influence of this region on HlyIIR properties and for a potential improvement in the crystallogenesis of the HlyIIR, we constructed a mutant of HlyIIR in which this disordered region is substituted by a single alanine residue. Biochemical analysis of the mutant indicated that it still forms a dimer but the DNA-binding activity is lost. HlyIIR mutant displayed improved crystallization properties and its structure was determined by X-ray crystallography at 2.1 A resolution. Unexpectedly, the structure shows that the HlyIIR mutant forms an alternative dimer with subunits rotated by 160 degrees. Moreover, there are also changes in the conformation of individual subunits. These dramatic structural rearrangements are caused by changes in the conformation of the segment Pro161-Ser169. We conclude that correct conformation of this segment is principal for maintaining the structure and activity of HlyIIR. [Contraction of the disordered loop located within C-terminal domain of the transcriptional regulator HlyIIR causes its structural rearrangement],Kovalevskii OV, Antson AA, Solonin AS Mol Biol (Mosk). 2009 Jan-Feb;43(1):126-35. PMID:19334535[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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