Myoglobin functioning as cytochrome P450 for biosensing of 2,4-dichlorophenol

Abstract

The interactions between 2,4-dichlorophenol (2,4-DCP) and myoglobin immobilized by agarose hydrogel on the surface of a glassy carbon electrode were explored by cyclic voltammetry. 2,4-DCP coordinating with the heme of myoglobin induces a negative shift in the formal potential of myoglobin without occurrence of a catalytic reaction in anaerobic solution. However, the immobilized myoglobin functioned as cytochrome P450 under the catalytic pathways of C-hydroxylation of 2,4-DCP in an air-saturated solution. The plot of current against 2,4-DCP concentration shows a linear relationship in the range of 12.5–208 μM. The limit of detection is calculated to be 2.06 μM. UV spectra confirm that 2,4-DCP interacts with the amino-acid residues of myoglobin as well as Mb-heme. This type of study can provide important insights into the mechanisms involved in the interaction of hemoproteins with chlorophenols. The methods possess potential applications in biotechnology and biosensors.