title: Mercury metallation of the copper protein azurin and structural insight into possible heavy metal reactivity.
abstract: Mercury(II) metallation of Pseudomonas aeruginosa azurin has been characterized structurally and biochemically. The X-ray crystal structure at 1.5Å of mercury(II) metallated azurin confirms the coordination of mercury at the copper binding active site and a second surface site. These findings are further validated by NMR, Matrix-assisted laser desorption/ionization spectrometry (MALDI), and UV-visible spectroscopic methods indicating copper displacement from the wild-type protein. Bioinformatic analysis has identified homologous human protein domains computationally, and compared them to the structure of azurin, providing a model for human mercury interactions. Study of the mercury-azurin adduct, in combination with other known examples of protein-heavy metal interactions, could provide further insight into the chemical mechanisms of toxicological interactions, leading toward a global understanding of the biological speciation of toxic heavy metals.
authors.affiliation: Department of Chemistry, The University of Akron, Akron, OH 44325, USA.
authors.forename: Anthony P
authors.initials: AP
authors.lastname: Zampino
authors.affiliation: Department of Chemistry, The University of Akron, Akron, OH 44325, USA.
authors.forename: Francesca M
authors.initials: FM
authors.lastname: Masters
authors.affiliation: Department of Chemistry and Biochemistry, University of Minnesota Duluth, 1039 University Dr., Duluth, MN 55812, USA.
authors.forename: Erika L
authors.initials: EL
authors.lastname: Bladholm
authors.affiliation: Department of Chemistry, The University of Akron, Akron, OH 44325, USA.
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: Panzner
authors.affiliation: Department of Chemistry and Biochemistry, University of Minnesota Duluth, 1039 University Dr., Duluth, MN 55812, USA.
authors.forename: Steven M
authors.initials: SM
authors.lastname: Berry
authors.affiliation: Department of Chemistry, The University of Akron, Akron, OH 44325, USA.
authors.forename: Thomas C
authors.initials: TC
authors.lastname: Leeper
authors.affiliation: Department of Chemistry, The University of Akron, Akron, OH 44325, USA. Electronic address: ziegler@uakron.edu.
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Ziegler
mesh_terms: D000595:Amino Acid Sequence; D001400:Azurin / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D001665:Binding Sites; D002413:Cations, Divalent; D002570:Ceruloplasmin / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D003300:Copper / Q000737:chemistry* / Q000378:metabolism; D018360:Crystallography, X-Ray; D004926:Escherichia coli / Q000737:chemistry / Q000235:genetics; D005169:Factor VIII / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D015870:Gene Expression; D006801:Humans; D008628:Mercury / Q000737:chemistry* / Q000378:metabolism; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D011550:Pseudomonas aeruginosa / Q000737:chemistry; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment; D040681:Structural Homology, Protein
chemical_list: D002413:Cations, Divalent; D011994:Recombinant Proteins; D001400:Azurin; D003300:Copper; D005169:Factor VIII; D002570:Ceruloplasmin; D008628:Mercury
keywords: Azurin; Bioinformatics; MALDI; Mercury; NMR; X-ray structure