*Review* **From Enzyme Stability to Enzymatic Bioelectrode Stabilization Processes**

**Charlène Beaufils, Hiu-Mun Man, Anne de Poulpiquet, Ievgen Mazurenko and Elisabeth Lojou \***

Aix Marseille University, CNRS, BIP, Bioénergétique et Ingénierie des Protéines, UMR 7281, 31, Chemin Joseph Aiguier, CS 70071 13402 Marseille CEDEX 09, France; cbeaufils@imm.cnrs.fr (C.B.); hman@imm.cnrs.fr (H.-M.M.); adepoulpiquet@imm.cnrs.fr (A.d.P.); imazurenko@imm.cnrs.fr (I.M.)

**\*** Correspondence: lojou@imm.cnrs.fr; Tel.: +33-(0)491-164-144

**Abstract:** Bioelectrocatalysis using redox enzymes appears as a sustainable way for biosensing, electricity production, or biosynthesis of fine products. Despite advances in the knowledge of parameters that drive the efficiency of enzymatic electrocatalysis, the weak stability of bioelectrodes prevents large scale development of bioelectrocatalysis. In this review, starting from the understanding of the parameters that drive protein instability, we will discuss the main strategies available to improve all enzyme stability, including use of chemicals, protein engineering and immobilization. Considering in a second step the additional requirements for use of redox enzymes, we will evaluate how far these general strategies can be applied to bioelectrocatalysis.

**Keywords:** enzyme; metalloenzyme; catalysis; stability; electrochemistry; bioelectrochemistry
