The many faces of the unusual biofilm activator RemA

Abstract

Biofilms can be viewed as tissue‐like structures in which microorganisms are organized in a spatial and functional sophisticated manner. Biofilm formation requires the orchestration of a highly integrated network of regulatory proteins to establish cell differentiation and production of a complex extracellular matrix. Here, we discuss the role of the essential Bacillus subtilis biofilm activator RemA. Despite intense research on biofilms, RemA is a largely underappreciated regulatory protein. RemA forms donut‐shaped octamers with the potential to assemble into dimeric superstructures. The presumed DNA‐binding mode suggests that RemA organizes its target DNA into nucleosome‐like structures, which are the basis for its role as transcriptional activator. We discuss how RemA affects gene expression in the context of biofilm formation, and its regulatory interplay with established components of the biofilm regulatory network, such as SinR, SinI, SlrR, and SlrA. We emphasize the additional role of RemA played in nitrogen metabolism and osmotic‐stress adjustment.

MutL significantly regulates the formation of biofilms in B. subtilis YT1

“…The DNA-binding protein SinR acts as the master regulator of bio lm formation, suppressing the expression of both operons (Stowe et al, 2014;Milton et al, 2020). Conversely, the protein RemA activates the expression of these operons (Prabhawathi et al, 2014;Bremer et al, 2022). The abrB gene also functions as a negative regulator of bio lm formation, and the AbrB-regulated genes sipW and yoaW are essential for normal bio lm formation (Weng et al, 2013).…”