title: Hydrolytic protein cleavage mediated by unusual mononuclear copper(II) complexes: X-ray structures and solution studies.
abstract: The crystal structures and redox and UV-vis/EPR spectroscopic properties of two new mononuclear copper(II) complexes, [Cu(HL1)Cl2] (1) and [Cu(L1)Cl] (2), prepared through the reaction between copper(II) chloride and the ligand 2-[(bis(pyridylmethyl)amino)methyl]-4-methyl-6-formylphenol (HL1) under distinct base conditions, are reported along with solution studies. Also, we demonstrate that these CuII complexes are able to cleave unactivated peptide bonds from bovine serum albumin (BSA) and the thermostable enzyme Taq DNA polymerase at micromolar concentration, under mild pH and temperature conditions. The cleavage activity seems to be specific with defined proteolytic fragments appearing after protein treatment. The location of the specific cleavage sites was tentatively assigned to solvent-accessible portions of the protein. These are two of the most active Cu(II) complexes described to date, since their cleavage activity is detected in minutes and evidence is here presented for a hydrolytic mechanism mediating protein cleavage by these complexes.
authors.affiliation: Laboratório de Expressão Gênica, Departamento de Bioquímica-CCB, Universidade Federal de Santa Catarina, 88040-900 Florianópolis, SC, Brazil.
authors.forename: Mauricio C B
authors.initials: MC
authors.lastname: de Oliveira
authors.forename: Marciela
authors.initials: M
authors.lastname: Scarpellini
authors.forename: Ademir
authors.initials: A
authors.lastname: Neves
authors.forename: Hernán
authors.initials: H
authors.lastname: Terenzi
authors.forename: Adailton J
authors.initials: AJ
authors.lastname: Bortoluzzi
authors.forename: Bruno
authors.initials: B
authors.lastname: Szpoganics
authors.forename: Alessandra
authors.initials: A
authors.lastname: Greatti
authors.forename: Antônio S
authors.initials: AS
authors.lastname: Mangrich
authors.forename: Emanuel M
authors.initials: EM
authors.lastname: de Souza
authors.forename: Pablo M
authors.initials: PM
authors.lastname: Fernandez
authors.forename: Marcia R
authors.initials: MR
authors.lastname: Soares
mesh_terms: D000818:Animals; D002413:Cations, Divalent; D002417:Cattle; D003300:Copper / Q000737:chemistry*; D018360:Crystallography, X-Ray; D004247:DNA / Q000737:chemistry / Q000378:metabolism; D004563:Electrochemistry; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D008024:Ligands; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000737:chemistry* / Q000378:metabolism; D010446:Peptide Fragments / Q000737:chemistry / Q000378:metabolism; D011506:Proteins / Q000737:chemistry / Q000378:metabolism*; D012709:Serum Albumin / Q000737:chemistry / Q000378:metabolism; D012996:Solutions; D013056:Spectrophotometry, Ultraviolet; D019914:Taq Polymerase / Q000737:chemistry / Q000378:metabolism; D013997:Time Factors
chemical_list: D002413:Cations, Divalent; D008024:Ligands; D009942:Organometallic Compounds; D010446:Peptide Fragments; D011506:Proteins; D012709:Serum Albumin; D012996:Solutions; D003300:Copper; D004247:DNA; D019914:Taq Polymerase