title: Microscale Crystals of Cytochrome c and Calixarene on Electrodes: Interprotein Electron Transfer between Defined Sites.
abstract: The assembly of redox proteins on electrodes is an important step in biosensor development. Recently, p-sulfonato-calix[4]arene was shown to act as "molecular glue" for the assembly and crystallization of cytochrome c (cyt c). Electrochemical data are presented for microscale cyt c-calixarene crystals grown on self-assembled monolayers (SAM)-modified Au electrodes. The crystals were characterized by cyclic voltammetry and exceptionally high concentrations of electroactive cyt c were obtained. The peak currents were found to increase linearly with the square root of the scan rate, thus allowing an evaluation of the rate constant for electron self-exchange. This study revealed high electroactivity accompanied by fast interprotein electron transfer in crystals, which may have implications for the construction of novel bioelectronic devices.
authors.affiliation: School of Chemistry, National University of Ireland Galway, University Road, Galway (Ireland).
authors.forename: Róise E
authors.initials: RE
authors.lastname: McGovern
authors.affiliation: Biosystems Technology, Institute of Applied Life Sciences, Technical University of Applied Sciences, Hochschulring 1, 15745 Wildau (Germany).
authors.forename: Sven C
authors.initials: SC
authors.lastname: Feifel
authors.affiliation: Biosystems Technology, Institute of Applied Life Sciences, Technical University of Applied Sciences, Hochschulring 1, 15745 Wildau (Germany). flisdat@th-wildau.de.
authors.forename: Fred
authors.initials: F
authors.lastname: Lisdat
authors.affiliation: School of Chemistry, National University of Ireland Galway, University Road, Galway (Ireland). peter.crowley@nuigalway.ie.
authors.forename: Peter B
authors.initials: PB
authors.lastname: Crowley
mesh_terms: D047250:Calixarenes / Q000737:chemistry*; D003460:Crystallization / Q000379:methods; D045304:Cytochromes c / Q000737:chemistry*; D055664:Electrochemical Techniques; D004566:Electrodes; D004579:Electron Transport; D008958:Models, Molecular; D010084:Oxidation-Reduction; D012441:Saccharomyces cerevisiae / Q000737:chemistry*; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry*
chemical_list: D029701:Saccharomyces cerevisiae Proteins; D047250:Calixarenes; D045304:Cytochromes c
keywords: calixarenes; crystal growth; heme proteins; molecular glue; redox chemistry