This is a sensor domain found in solute-binding protein family 3 members from Gram-positive bacteria, Gram-negative bacteria and archaea. It can also be found in the N-terminal of the membrane-bound lytic murein transglycosylase F (MltF) protein. This domain recognises Nicotinate, quidalnate, pyridine-2,5-dicarboxylate and salicylate [1].

1: A catalogue of signal molecules that interact with sensor kinases, chemoreceptors and transcriptional regulators. Matilla MA, Velando F, Martin-Mora D, Monteagudo-Cascales E, Krell T; FEMS Microbiol Rev. 2022;46:fuab043. PMID:34424339