Chapter 2.3 - Biofilms: Microbial Life on the Electrode Surface

Abstract

Biofilm formation is an important biological concept in environmental microbiology, wherein the microbial cells adapt to multicellular lifestyle by formation of biofilm during which the bacterial cells are self-immobilized in extracellular polymeric matrix. This chapter provides an insight into the concept of biofilm formation by microorganisms traditionally/naturally and in bioelectrochemical systems. The dynamics of biofilm formation, changes in gene expression due to biofilm, the regulatory mechanisms, and factors associated with biofilm formation on the electrode surface were discussed. The importance of electrogenic bacteria in biofilm formation and the differences with nonconducting biofilms are debated. The changes in gene expression in electrogenic model bacteria such as Shewanella oneidensis MR-1 and Geobacter sulfurreducens during electron transfer to electrode were specially mentioned. Finally, an overview of the concept of conductive “artificial biofilms” was also presented in this chapter.