Spectroelectrochemical study revealing the redox potential of human monoamine oxidase A

摘要: Abstract Spectroelectrochemical measurements were performed on human monoamine oxidase A (MAO A) at pH 7.8, and the redox potential of enzyme was determined. MAOs are membrane-bound flavoenzymes that catalyse oxidation different neurotransmitters such as dopamine, serotonin or norepinephrine. As redox-active cofactor enzymes contain a covalently bound 8α-S-cysteinyl-flavin adenine dinucleotide (8α-S-cysteinyl-FAD). The spectroelectrochemical in presence various one- two-electron transferring mediators viologens 1,4-naphthoquinones. No singly reduced flavosemiquinone radical anion could be detected timescale experiment, i.e. changes from fully oxidized flavoquinone to flavohydroquinone. of −177 ± 4 mV vs. NHE determined 7.8. Neither ionic strength buffer, nor composition mediator mixture, passivation gold capillary electrode surface by chemisorption mercaptohexanol had any influence values for potential.