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The enzyme Mt PerII is a new peroxidase which has been isolated only recently from fungus Myceliophthora thermophila and has significant thermostability and stability at high H 2 O 2 concentrations. In the present work, an electrochemical kinetic study, based on cyclic voltammetry, is performed for the first time for the catalytic decomposition of H 2 O 2 by Mt PerII, at 18 °C. Leuco methylene blue (LMB) is used as a mediator and the catalytic and Michaelis constants are determined, assuming a Michaelis-Menten mechanism. Experimental evidence suggest the absence of inhibition by H 2 O 2 , for concentrations up to 16 mM, and increasing catalytic activity for temperatures up to 50 °C. Moreover, a modified electrode is constructed, by attempting the entrapment of Mt PerII on a dodecanothiol self-assembled monolayer on gold. The modified electrode is studied chronoamperometrically in solutions containing methylene blue mediator and different concentrations of H 2 O 2 . It is shown that adsorbed Mt PerII retains its activity and the modified electrode exhibits a considerably high linear region for the detection of H 2 O 2 . The experimental findings indicate that Mt PerII is a new candidate for analytical and industrial applications. [ABSTRACT FROM AUTHOR]

• Mt LPMO9H is immobilized and direct electron transfer is achieved. • The interaction of Mt LPMO9H with PASC is studied with FTacV. • The kinetic model for the interaction of Mt LPMO9H with PASC with FTacV is developed. • The kinetic constant for the interaction of Mt LPMO9H with PASC is extracted. In this work, a lytic polysaccharide monooxygenase (LPMO) belonging to the AA9 family from the filamentous fungus Thermothelomyces thermophilus , Mt LPMO9H, is immobilized on cobalt functionalized multi-walled carbon nanotubes modified glassy carbon electrode. The step of the binding of phosphoric acid swollen cellulose on this LPMO is studied using large amplitude fast Fourier transform alternating current voltammetry (FTacV) at different temperatures, extracting the corresponding kinetic constants, based on a model developed for the interaction of immobilized enzyme with free, in the solution, species. [ABSTRACT FROM AUTHOR]

In the present work, the derivation of the standard rate constant k 0, the transfer coefficient a and the standard (or formal) potential E 0 of immobilized electroactive species, with the use of large amplitude Fourier transform alternating current cyclic voltammetry (FTacV) is examined. Both the kinetic equation of the coverage and the current integral equation are solved. The kinetic regions of the current response are distinguished, the chief observables in the case of both fast and slow kinetics are showcased and finally based on these, a methodology to extract k 0, a and E 0 is introduced. • The effect of the kinetic parameters on chief observables is determined. • Chief observables for reversible and irreversible kinetics are examined. • Methodologies to extract kinetic and thermodynamic parameters are introduced. [ABSTRACT FROM AUTHOR]