title: De Novo Construction of Redox Active Proteins.
abstract: Relatively simple principles can be used to plan and construct de novo proteins that bind redox cofactors and participate in a range of electron-transfer reactions analogous to those seen in natural oxidoreductase proteins. These designed redox proteins are called maquettes. Hydrophobic/hydrophilic binary patterning of heptad repeats of amino acids linked together in a single-chain self-assemble into 4-alpha-helix bundles. These bundles form a robust and adaptable frame for uncovering the default properties of protein embedded cofactors independent of the complexities introduced by generations of natural selection and allow us to better understand what factors can be exploited by man or nature to manipulate the physical chemical properties of these cofactors. Anchoring of redox cofactors such as hemes, light active tetrapyrroles, FeS clusters, and flavins by His and Cys residues allow cofactors to be placed at positions in which electron-tunneling rates between cofactors within or between proteins can be predicted in advance. The modularity of heptad repeat designs facilitates the construction of electron-transfer chains and novel combinations of redox cofactors and new redox cofactor assisted functions. Developing de novo designs that can support cofactor incorporation upon expression in a cell is needed to support a synthetic biology advance that integrates with natural bioenergetic pathways.
authors: University of Pennsylvania, Philadelphia, PA, United States.
authors: C C
authors: CC
authors: Moser
authors: University of Pennsylvania, Philadelphia, PA, United States.
authors: M M
authors: MM
authors: Sheehan
authors: University of Pennsylvania, Philadelphia, PA, United States.
authors: N M
authors: NM
authors: Ennist
authors: University of Pennsylvania, Philadelphia, PA, United States.
authors: G
authors: G
authors: Kodali
authors: University of Pennsylvania, Philadelphia, PA, United States.
authors: C
authors: C
authors: Bialas
authors: University of Pennsylvania, Philadelphia, PA, United States.
authors: M T
authors: MT
authors: Englander
authors: University of Pennsylvania, Philadelphia, PA, United States.
authors: B M
authors: BM
authors: Discher
authors: University of Pennsylvania, Philadelphia, PA, United States. Electronic address: dutton@mail.med.upenn.edu.
authors: P L
authors: PL
authors: Dutton
mesh_terms: D000596:Amino Acids / Q000737:chemistry*; D004583:Electrons; D006418:Heme / Q000737:chemistry*; D057927:Hydrophobic and Hydrophilic Interactions; D010084:Oxidation-Reduction; D000072756:Protein Conformation, alpha-Helical; D015202:Protein Engineering / Q000379:methods*; D017433:Protein Structure, Secondary; D011506:Proteins / Q000138:chemical synthesis / Q000737:chemistry*; D045725:Tetrapyrroles / Q000737:chemistry
chemical_list: D000596:Amino Acids; D011506:Proteins; D045725:Tetrapyrroles; D006418:Heme
keywords: De novo protein; Electron tunneling; Electron-transfer protein; Helical bundle; Protein cofactors; Protein design; Redox cofactor