title: HENRYK - An endless source of metal coordination surprises.
abstract: The basic knowledge about biological inorganic chemistry, thermodynamics and metal binding sites of metalloproteins is crucial for the understanding of their metal binding-structure-function relationship. Metal-peptide complexes are useful and commonly used models of metal-enzyme active sites, among which copper and zinc models are one of the most extensively studied. HENRYK is a peptide sequence present in numerous proteins, and serves as a potentially tempting binding site for Cu2+and Zn2+. Maybe more importantly, HENRYK also happens to be the first name of our group leader. The results of this work, which, at the first glance, might seem to be a 'chemical scrabble', went far beyond our expectations and surprised us with a novel, uncommon behavior of a Cu2+complex with a peptide with a histidine in position one. At low pH, the binding is a typical histamine-like coordination, but with the increase of pH, the imidazole nitrogen is moved to the axial position and replaced with an amide; at basic pH, the binding mode is a {NH2, 3N-} one in the equatorial plane. It is important to note, that no dimeric species are formed in between. Such binding is thermodynamically much more stable than a simple complex with histamine, and quite comparable to complexes with several possible imidazole anchoring sites.
authors.affiliation: Faculty of Chemistry, University of Wroclaw, F. Joliot-Curie 14, 50-383 Wrocław, Poland.
authors.forename: Paulina
authors.initials: P
authors.lastname: Kołkowska
authors.affiliation: Faculty of Chemistry, University of Wroclaw, F. Joliot-Curie 14, 50-383 Wrocław, Poland.
authors.forename: Aleksandra
authors.initials: A
authors.lastname: Hecel
authors.affiliation: Faculty of Chemistry, University of Wroclaw, F. Joliot-Curie 14, 50-383 Wrocław, Poland.
authors.forename: Dorota
authors.initials: D
authors.lastname: Kędzierska
authors.affiliation: Faculty of Chemistry, University of Wroclaw, F. Joliot-Curie 14, 50-383 Wrocław, Poland.
authors.forename: Małgorzata
authors.initials: M
authors.lastname: Ostrowska
authors.affiliation: Faculty of Chemistry, University of Wroclaw, F. Joliot-Curie 14, 50-383 Wrocław, Poland.
authors.forename: Paulina K
authors.initials: PK
authors.lastname: Walencik
authors.affiliation: Faculty of Chemistry, University of Wroclaw, F. Joliot-Curie 14, 50-383 Wrocław, Poland.
authors.forename: Joanna
authors.initials: J
authors.lastname: Wątły
authors.affiliation: Faculty of Chemistry, University of Wroclaw, F. Joliot-Curie 14, 50-383 Wrocław, Poland.
authors.forename: Karolina
authors.initials: K
authors.lastname: Zdyb
authors.affiliation: Faculty of Chemistry, University of Gdańsk, Wita Stwosza 63, 80-308 Gdańsk, Poland.
authors.forename: Marta
authors.initials: M
authors.lastname: Spodzieja
authors.affiliation: Faculty of Chemistry, University of Gdańsk, Wita Stwosza 63, 80-308 Gdańsk, Poland.
authors.forename: Sylwia
authors.initials: S
authors.lastname: Rodziewicz-Motowidło
authors.affiliation: Faculty of Chemistry, University of Wroclaw, F. Joliot-Curie 14, 50-383 Wrocław, Poland.
authors.forename: Sławomir
authors.initials: S
authors.lastname: Potocki
authors.affiliation: Faculty of Chemistry, University of Wroclaw, F. Joliot-Curie 14, 50-383 Wrocław, Poland.
authors.forename: Marek
authors.initials: M
authors.lastname: Łuczkowski
authors.affiliation: Faculty of Chemistry, University of Wroclaw, F. Joliot-Curie 14, 50-383 Wrocław, Poland.
authors.forename: Elżbieta
authors.initials: E
authors.lastname: Gumienna-Kontecka
authors.affiliation: Faculty of Chemistry, University of Wroclaw, F. Joliot-Curie 14, 50-383 Wrocław, Poland. Electronic address: magdalena.rowinska-zyrek@chem.uni.wroc.pl.
authors.forename: Magdalena
authors.initials: M
authors.lastname: Rowińska-Żyrek
mesh_terms: D056831:Coordination Complexes / Q000737:chemistry*; D003300:Copper / Q000737:chemistry*; D006632:Histamine / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D010455:Peptides / Q000737:chemistry*; D015032:Zinc / Q000737:chemistry*
chemical_list: D056831:Coordination Complexes; D010455:Peptides; D003300:Copper; D006632:Histamine; D015032:Zinc
keywords: Histamine-like binding; Metal–peptide complexes; Thermodynamic stability