title: Alteration of the oxygen-dependent reactivity of de novo Due Ferri proteins.
abstract: De novo proteins provide a unique opportunity to investigate the structure-function relationships of metalloproteins in a minimal, well-defined and controlled scaffold. Here, we describe the rational programming of function in a de novo designed di-iron carboxylate protein from the Due Ferri family. Originally created to catalyse the O(2)-dependent, two-electron oxidation of hydroquinones, the protein was reprogrammed to catalyse the selective N-hydroxylation of arylamines by remodelling the substrate access cavity and introducing a critical third His ligand to the metal-binding cavity. Additional second- and third-shell modifications were required to stabilize the His ligand in the core of the protein. These structural changes resulted in at least a 10(6)-fold increase in the relative rate between the arylamine N-hydroxylation and hydroquinone oxidation reactions. This result highlights the potential for using de novo proteins as scaffolds for future investigations of the geometric and electronic factors that influence the catalytic tuning of di-iron active sites.
authors.affiliation: Department of Biochemistry & Biophysics, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA. areig@ursinus.edu
authors.forename: Amanda J
authors.initials: AJ
authors.lastname: Reig
authors.forename: Marcos M
authors.initials: MM
authors.lastname: Pires
authors.forename: Rae Ana
authors.initials: RA
authors.lastname: Snyder
authors.forename: Yibing
authors.initials: Y
authors.lastname: Wu
authors.forename: Hyunil
authors.initials: H
authors.lastname: Jo
authors.forename: Daniel W
authors.initials: DW
authors.lastname: Kulp
authors.forename: Susan E
authors.initials: SE
authors.lastname: Butch
authors.forename: Jennifer R
authors.initials: JR
authors.lastname: Calhoun
authors.forename: Thomas
authors.initials: T
authors.lastname: Szyperski
authors.forename: Thomas G
authors.initials: TG
authors.lastname: Szyperski
authors.forename: Edward I
authors.initials: EI
authors.lastname: Solomon
authors.forename: William F
authors.initials: WF
authors.lastname: DeGrado
mesh_terms: D000595:Amino Acid Sequence; D002570:Ceruloplasmin / Q000378:metabolism; D015195:Drug Design; D004583:Electrons; D006873:Hydroquinones / Q000737:chemistry / Q000378:metabolism; D006900:Hydroxylation; D033862:Iron-Binding Proteins / Q000737:chemistry* / Q000378:metabolism*; D007700:Kinetics; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010100:Oxygen / Q000378:metabolism*; D017510:Protein Folding; D055550:Protein Stability; D017433:Protein Structure, Secondary
chemical_list: D006873:Hydroquinones; D033862:Iron-Binding Proteins; D002570:Ceruloplasmin; D010100:Oxygen; C031927:hydroquinone