title: A novel copper site in a cyanobacterial metallochaperone.
abstract: The thylakoid lumen of the cyanobacterium Synechocystis PCC 6803 is supplied with copper via two copper-transporting ATPases and a metallochaperone intermediary. We show that the copper site of this metallochaperone is unusual and consists of two cysteine residues and a histidine imidazole located on structurally dynamic loops. Substitution of this histidine residue enhances bacterial two-hybrid interaction with the cytosolic copper exporter, but not the copper importer, suggesting that the interacting surfaces are distinct, with implications for metal transfer.
authors.affiliation: Cell and Molecular Biosciences, Medical School, University of Newcastle, Newcastle upon Tyne NE2 4HH, UK.
authors.forename: Gilles P M
authors.initials: GP
authors.lastname: Borrelly
authors.forename: Claudia A
authors.initials: CA
authors.lastname: Blindauer
authors.forename: Ralf
authors.initials: R
authors.lastname: Schmid
authors.forename: Clive S
authors.initials: CS
authors.lastname: Butler
authors.forename: Chris E
authors.initials: CE
authors.lastname: Cooper
authors.forename: Ian
authors.initials: I
authors.lastname: Harvey
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Sadler
authors.forename: Nigel J
authors.initials: NJ
authors.lastname: Robinson
mesh_terms: D018528:ATP-Binding Cassette Transporters; D000251:Adenosine Triphosphatases / Q000378:metabolism; D019943:Amino Acid Substitution; D001426:Bacterial Proteins / Q000378:metabolism; D001665:Binding Sites; D002352:Carrier Proteins / Q000378:metabolism; D027682:Cation Transport Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D003300:Copper / Q000032:analysis / Q000737:chemistry* / Q000378:metabolism; D000458:Cyanobacteria / Q000737:chemistry* / Q000378:metabolism; D003545:Cysteine / Q000032:analysis; D005288:Ferredoxins / Q000737:chemistry; D006639:Histidine / Q000032:analysis / Q000737:chemistry; D017136:Ion Transport; D008958:Models, Molecular; D017510:Protein Folding
chemical_list: D018528:ATP-Binding Cassette Transporters; D001426:Bacterial Proteins; D002352:Carrier Proteins; D027682:Cation Transport Proteins; D005288:Ferredoxins; D006639:Histidine; D003300:Copper; D000251:Adenosine Triphosphatases; D003545:Cysteine