Bioelectrochemical system (BES), in which electrode reaction is driven by electrochemically active microorganisms (EAM) to recovery energy, degrade contaminants and synthesize high additional value compounds, is a promising biotechnology. EAM is the basis of BES, microorganisms-electrode interaction plays a key role in BES functioning. In contrast with the expanding of BES function, especially BES cathode, the diversity of isolated EAM is limited, and most of them are applied in anode to generate a high power density. In addition, the understanding of microorganisms-electrode interaction mostly confines in Geobacter and Shewanella genus. In this article, we review medium, culture condition and microorganisms identification, as well as cyclic voltammetry, differential pulse voltammetry and chronoamperometry for the isolation and identification of EAMs. We further highlight the research trends of expanding EAM diversity and of microorganisms-electrode interaction, which would promote the application of BES in environmental control and bioenergy production.

Contents
1 Introduction
2 Electrochemically active microorganisms
3 Microorganism isolation
3.1 Culture medium
3.2 Culture condition
4 Microorganism biological identification
4.1 16S/18S rRNA gene sequencing and analysis
4.2 Morphological, physiological and biochemical characterization
5 Characterization of electrochemical activity
5.1 Cyclic voltammetry
5.2 Differential pulse voltammetry and square wave voltammetry
5.3 Chronoamperometry
6 Outlook