title: Dissection of the sensor domain of the copper-responsive histidine kinase CorS from Myxococcus xanthus.
abstract: Myxococcus xanthus CorSR is a two-component system responsible for maintaining the response of this bacterium to copper. In the presence of this metal it upregulates, among others, the genes encoding the multicopper oxidase CuoA and the P1B -ATPase CopA. Dissection of the periplasmic sensor domain of the histidine kinase CorS by the analysis of a series of in-frame deletion mutants generated in this portion of the protein has revealed that copper sensing requires a region of 28 residues in the N terminus and another region of nine residues in the C terminus. Point mutations at His34, His38 and His171 demonstrate that they are essential for the ability of CorS to sense copper. Furthermore, the use of a bacterial two-hybrid system has revealed dimerization between monomers of CorS even in the absence of any metal, and that copper enhances this interaction. When dimerization was tested with proteins mutated at the three essential His residues, it was observed that these proteins maintain the intrinsic dimerization ability in the absence of metal. In contrast to the wild-type protein, copper did not strengthen the interaction, corroborating that copper binding to the three His residues of CorS is required for enhancing dimerization and transmitting the signal.
authors.affiliation: Departamento de Microbiología, Facultad de Ciencias, Universidad de Granada, Avda, Fuentenueva s/n, E-18071, Granada, Spain.
authors.forename: María Celestina
authors.initials: MC
authors.lastname: Sánchez-Sutil
authors.affiliation: Departamento de Microbiología, Facultad de Ciencias, Universidad de Granada, Avda, Fuentenueva s/n, E-18071, Granada, Spain.
authors.forename: Francisco Javier
authors.initials: FJ
authors.lastname: Marcos-Torres
authors.affiliation: Departamento de Microbiología, Facultad de Ciencias, Universidad de Granada, Avda, Fuentenueva s/n, E-18071, Granada, Spain.
authors.forename: Juana
authors.initials: J
authors.lastname: Pérez
authors.affiliation: Departamento de Microbiología, Facultad de Ciencias, Universidad de Granada, Avda, Fuentenueva s/n, E-18071, Granada, Spain.
authors.forename: María
authors.initials: M
authors.lastname: Ruiz-González
authors.affiliation: Departamento de Microbiología, Facultad de Ciencias, Universidad de Granada, Avda, Fuentenueva s/n, E-18071, Granada, Spain.
authors.forename: Elena
authors.initials: E
authors.lastname: García-Bravo
authors.affiliation: Departamento de Bioquímica y Biología Molecular II, Facultad de Farmacia, Universidad de Granada, Campus de Cartuja, E-18071, Granada, Spain.
authors.forename: Marina
authors.initials: M
authors.lastname: Martínez-Cayuela
authors.affiliation: Departamento de Microbiología, Facultad de Ciencias, Universidad de Granada, Avda, Fuentenueva s/n, E-18071, Granada, Spain.
authors.forename: Nuria
authors.initials: N
authors.lastname: Gómez-Santos
authors.affiliation: Departamento de Microbiología, Facultad de Ciencias, Universidad de Granada, Avda, Fuentenueva s/n, E-18071, Granada, Spain.
authors.forename: Aurelio
authors.initials: A
authors.lastname: Moraleda-Muñoz
authors.affiliation: Departamento de Microbiología, Facultad de Ciencias, Universidad de Granada, Avda, Fuentenueva s/n, E-18071, Granada, Spain.
authors.forename: José
authors.initials: J
authors.lastname: Muñoz-Dorado
mesh_terms: D003300:Copper / Q000378:metabolism*; D004252:DNA Mutational Analysis; D000071677:Histidine Kinase / Q000235:genetics* / Q000378:metabolism*; D016941:Myxococcus xanthus / Q000201:enzymology*; D017354:Point Mutation; D055503:Protein Multimerization; D017384:Sequence Deletion; D020798:Two-Hybrid System Techniques
chemical_list: D003300:Copper; D000071677:Histidine Kinase