title: Modular synthesis of de novo-designed metalloproteins for light-induced electron transfer.
abstract: The design and chemical synthesis of two de novo four-helix bundle proteins is described; each protein has two bound cofactors. Their construction from purified peptides is based on the modular assembly of different amphiphilic helices by chemoselective coupling to a cyclic peptide template. In the hydrophobic interior of the antiparallel four-helix bundle these proteins contain a heme in a binding pocket with two ligating histidine residues. A ruthenium-tris(bipyridine) complex is covalently bound to different positions at the hydrophilic side of one of the heme-binding helices. Laser-induced electron transfer across the varied distance through this helix has been studied and compared with a pathway analysis. The UV-visible, CD, and mass spectra are consistent with the structure and orientation predetermined by the template.
authors.affiliation: Institut für Biologie II/Biochemie, Albert-Ludwigs-Universität Freiburg, Schänzlestrasse 1, D-79104 Freiburg, Germany.
authors.forename: H K
authors.initials: HK
authors.lastname: Rau
authors.forename: N
authors.initials: N
authors.lastname: DeJonge
authors.forename: W
authors.initials: W
authors.lastname: Haehnel
mesh_terms: D000595:Amino Acid Sequence; D002942:Circular Dichroism; D015195:Drug Design; D004355:Drug Stability; D004579:Electron Transport / Q000528:radiation effects; D006418:Heme / Q000737:chemistry; D008027:Light; D008667:Metalloproteins / Q000138:chemical synthesis* / Q000378:metabolism* / Q000528:radiation effects; D008958:Models, Molecular; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010084:Oxidation-Reduction; D011487:Protein Conformation; D017433:Protein Structure, Secondary; D012428:Ruthenium / Q000737:chemistry
chemical_list: D008667:Metalloproteins; D006418:Heme; D012428:Ruthenium