title: Cloning, expression, crystallization and crystallographic analysis of CouR from Rhodopseudomonas palustris.
abstract: CouR from Rhodopseudomonas palustris is a member of the MarR transcriptional regulator family. It regulates the expression of CouA and CouB, enzymes that are involved in the degradation of p-coumarate. In vivo, CouR binds to a DNA fragment containing the couAB promoter and suppresses the expression of CouA and CouB, while binding of p-coumaroyl-CoA attenuates its affinity towards DNA and activates the expression of CouA and CouB. Here, the crystallization and X-ray diffraction analyses of CouR alone and in complex with p-coumaroyl-CoA are reported. Apo and ligand-complexed CouR crystals diffracted to 2.5 and 3.3 Å resolution, respectively. The crystals of apo CouR belonged to space group P22121, with unit-cell parameters a = 62.78, b = 76.15, c = 87.38 Å, whereas the crystals of the CouR-ligand complex belonged to space group P212121, with unit-cell parameters a = 61.37, b = 69.82, c = 70.32 Å. The crystals were predicted to contain two CouR molecules or CouR-ligand complexes per asymmetric unit.
authors.affiliation: College of Biological Science and Technology, Beijing Forestry University, Beijing 100083, People's Republic of China.
authors.forename: Chen
authors.initials: C
authors.lastname: Pan
authors.affiliation: National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, 15 Datun Road, Beijing 100101, People's Republic of China.
authors.forename: Yong Lin
authors.initials: YL
authors.lastname: Hu
authors.affiliation: College of Biological Science and Technology, Beijing Forestry University, Beijing 100083, People's Republic of China.
authors.forename: Xiang Ning
authors.initials: XN
authors.lastname: Jiang
authors.affiliation: College of Biological Science and Technology, Beijing Forestry University, Beijing 100083, People's Republic of China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Gai
mesh_terms: D000214:Acyl Coenzyme A / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics; D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000096:biosynthesis* / Q000737:chemistry / Q000235:genetics*; D001483:Base Sequence; D003001:Cloning, Molecular / Q000379:methods*; D003373:Coumaric Acids / Q000737:chemistry; D003460:Crystallization; D018360:Crystallography, X-Ray; D015964:Gene Expression Regulation, Bacterial; D008969:Molecular Sequence Data; D011422:Propionates; D012241:Rhodopseudomonas / Q000235:genetics* / Q000378:metabolism
chemical_list: D000214:Acyl Coenzyme A; D001426:Bacterial Proteins; D003373:Coumaric Acids; D011422:Propionates; C058644:4-coumaroyl-coenzyme A; C495469:p-coumaric acid
keywords: MarR family; crystallographic study; lignin; p-coumarate; protein–ligand complex; transcriptional regulator