title: Crystal structure of the caseinolytic protease gene regulator, a transcriptional activator in actinomycetes.
abstract: Human pathogens of the genera Corynebacterium and Mycobacterium possess the transcriptional activator ClgR (clp gene regulator) which in Corynebacterium glutamicum has been shown to regulate the expression of the ClpCP protease genes. ClgR specifically binds to pseudo-palindromic operator regions upstream of clpC and clpP1P2. Here, we present the first crystal structure of a ClgR protein from C. glutamicum. The structure was determined from two different crystal forms to resolutions of 1.75 and 2.05 A, respectively. ClgR folds into a five-helix bundle with a helix-turn-helix motif typical for DNA-binding proteins. Upon dimerization the two DNA-recognition helices are arranged opposite to each other at the protein surface in a distance of approximately 30 A, which suggests that they bind into two adjacent major grooves of B-DNA in an anti-parallel manner. A binding pocket is situated at a strategic position in the dimer interface and could possess a regulatory role altering the positions of the DNA-binding helices.
authors.affiliation: Swiss Light Source, Paul Scherrer Institut, Villigen PSI CH-5232, Switzerland.
authors.forename: Santina
authors.initials: S
authors.lastname: Russo
authors.forename: Jens-Eric
authors.initials: JE
authors.lastname: Schweitzer
authors.forename: Tino
authors.initials: T
authors.lastname: Polen
authors.forename: Michael
authors.initials: M
authors.lastname: Bott
authors.forename: Ehmke
authors.initials: E
authors.lastname: Pohl
mesh_terms: D020816:Amino Acid Motifs / Q000502:physiology; D001426:Bacterial Proteins / Q000737:chemistry* / Q000378:metabolism; D001665:Binding Sites / Q000502:physiology; D048230:Corynebacterium glutamicum / Q000737:chemistry / Q000145:classification* / Q000378:metabolism; D018360:Crystallography, X-Ray; D019281:Dimerization; D010447:Peptide Hydrolases / Q000096:biosynthesis; D020836:Protein Structure, Quaternary / Q000502:physiology; D014157:Transcription Factors / Q000737:chemistry* / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D014157:Transcription Factors; D010447:Peptide Hydrolases