This family of mostly uncharacterised proteins includes the extracellular matrix regulatory protein A (RemA) from Bacillus subtilis. RemA is required for biosynthesis of the extracellular matrix and biofilm formation [1,2]. It binds to DNA at multiple sites upstream of the promoters of the operons eps and tapA-sipW-tasA, which are required for the synthesis of the extracellular matrix components, extracellular polysaccharide and TasA amyloid proteins. SinR negatively regulates eps operon expression by occluding RemA binding [1]. Structure of RemA homologue from Geobacillus thermodenitrificans revealed that it forms an unique octameric ring with the potential to form a 16-meric superstructure and suggests that RemA can wrap DNA around its ring-like structure [2].

1: RemA is a DNA-binding protein that activates biofilm matrix gene expression in Bacillus subtilis. Winkelman JT, Bree AC, Bate AR, Eichenberger P, Gourse RL, Kearns DB; Mol Microbiol. 2013;88:984-997. PMID:23646920

2: Structural and functional characterization of the bacterial biofilm activator RemA. Hoffmann T, Mrusek D, Bedrunka P, Burchert F, Mais CN, Kearns DB, Altegoer F, Bremer E, Bange G; Nat Commun. 2021;12:5707. PMID:34588455