Characterization of cyanide binding to cytochrome c oxidase immobilized in electrode-supported lipid bilayer membranes

Electrochemical checking of aerobic isolates from electrochemically active biofilms formed in compost

“…Many biological compounds adsorbed or immobilized on the surface of carbon or graphite electrodes are known to catalyse oxygen reduction through direct electron transfer with the electrode. Many iron-based proteins have been investigated; haeme proteins, such as haemoglobin, myoglobin (Li and Hu 2003;Shen and Hu 2004), cytochrome P450 (Pardo-Jacques et al 2006;Shumyantseva et al 2007), and enzymes such as cytochrome c oxidase (Katz et al 1999;Shin et al 2003;Su et al 2004), peroxidase (Bogdanovskaya et al 2000;Huang and Hu 2001;Li and Hu 2003;Shen and Hu 2004), catalase (Lai and Bergel 2000;Salimi et al 2005), are among the most widely studied. A number of studies have focused on the oxygen reduction through the copper-containing enzymes, laccase and bilirubin oxidase, as reviewed by Shleev et al (Shleev et al 2005a,b;Tsujimura et al 2005;Stolarczyk et al 2007;Weigel et al 2007).…”

Direct Electrochemistry of Redox Enzymes as a Tool for Mechanistic Studies

“…Transmembrane enzymes (pyruvate oxidase, Complex II, cytochrome b o 3 ) have been incorporated in electrode-supported lipid bilayers; in these cases, the physiological activity was clearly retained but ET was mediated by the natural cosubstrate, a quinone located in the membrane, rather than direct. Cytochrome c oxidases from various organisms were also immobilized in supported bilayers aimed at providing a native-like environment; – ,, in these studies, the emphasis was on spectroscopic rather than kinetic properties.…”

The “Interface” in Analytical Chemistry: Overview and Historical Perspective

“…Bilayers have been attached to electrodes to create natural biological environments for studying the electron transfer properties of redox active biomolecules. Figure 4 illustrates an engineered electrode-solution interface designed to probe the electron transfer properties of the heme-copper protein cytochrome c-oxidase (41)(42)(43). This layered interface simulates the enzyme's native mitochondrial environment within a bilayer while allowing the active site to make reproducible direct contact with a silver electrode (41)(42)(43).…”

“…Figure 4 illustrates an engineered electrode-solution interface designed to probe the electron transfer properties of the heme-copper protein cytochrome c-oxidase (41)(42)(43). This layered interface simulates the enzyme's native mitochondrial environment within a bilayer while allowing the active site to make reproducible direct contact with a silver electrode (41)(42)(43). The design produced a Nernstian response in both cyclic voltammetry and potentiometric measurements without the use of mediators (43).…”