This domain is found at the N-terminal end of the transcriptional regulator VC_A0952 from Vibrio cholerae (VpsT), in CsgD from Salmonella typhimurium and other proteins predominantly found in proteobacteria. VpsT inversely regulates biofilm formation and motility. Like CsgD, it is organised into two domains: an N-terminal regulatory receiver domain (REC, this entry) and a C-terminal helix-turn-helix domain (Pfam:PF00196). This domain shows five alpha- helices and five beta-strands, with the beta-strands stabilising as a parallel beta-sheet surrounded by the alpha-helices [1,2].

1: Vibrio cholerae VpsT regulates matrix production and motility by directly sensing cyclic di-GMP. Krasteva PV, Fong JC, Shikuma NJ, Beyhan S, Navarro MV, Yildiz FH, Sondermann H; Science. 2010;327:866-868. PMID:20150502

2: Crystal structure of master biofilm regulator CsgD regulatory domain reveals an atypical receiver domain. Wen Y, Ouyang Z, Devreese B, He W, Shao Y, Lu W, Zheng F; Protein Sci. 2017;26:2073-2082. PMID:28758290