RESUMEN
All connected: a protein-immobilized electrode comprising hierarchical assemblies of photoactive cytochrome b(562) reconstituted with zinc protoporphyrin IX exhibits remarkably enhanced photocurrent generation relative to an electrode bearing a single zinc-substituted hemoprotein layer. The protein oligomers, which bear a covalently linked protoporphyrin group, assemble by a supramolecular heme/heme pocket interaction.
Asunto(s)
Oro/química , Hemoproteínas/metabolismo , Zinc/química , Citocromos b/química , Citocromos b/genética , Citocromos b/metabolismo , Electrodos , Hemoproteínas/química , Proteínas Inmovilizadas/química , Proteínas Inmovilizadas/metabolismo , Procesos Fotoquímicos , Protoporfirinas/química , Tecnicas de Microbalanza del Cristal de CuarzoRESUMEN
Supramolecular protein polymers: When a heme moiety was introduced to the surface of an apo-cytochrome b(562)(H63C) mutant, supramolecular polymers formed through noncovalent heme-heme pocket interactions. The incorporation of a heme triad as a pivot molecule in the protein polymer further led to a two-dimensional protein network structure, which was visualized by tapping-mode atomic force microscopy (see picture).
Asunto(s)
Citocromos b/química , Citocromos b/metabolismo , Hemo/química , Hemo/metabolismo , Citocromos b/genética , Citocromos b/ultraestructura , Hemo/análogos & derivados , Isomerismo , Microscopía de Fuerza Atómica , Mutación , Unión Proteica , Conformación Proteica , Dominios y Motivos de Interacción de ProteínasRESUMEN
Hierarchical assemblies of the noteworthy photoactive cytochrome b562 reconstituted with zinc protoporphyrin IX covalently linked with the protein surface were constructed on a gold electrode modified with an apoprotein of cytochrome b562. The integrated photoactive hemoproteins were characterized by electrochemical impedance and quartz crystal microbalance analyses. The protein-immobilized electrode exhibits enhanced photocurrent generation relative to the one having a Zn-substituted hemoprotein monolayer.