(2R,3R)-Butane-2,3-diol

(2R,3R)-Butane-2,3-diol is a non-covalent, reversible agonist targeting lanthanum (La³⁺)-sensitive calcium channels in bacteria (e.g., Escherichia coli) with an EC₅₀ of approximately 25 mM. (2R,3R)-Butane-2,3-diol binds to calcium channel proteins or related complexes, induces channel opening, promotes extracellular calcium influx, and triggers intracellular calcium transients, which may regulate bacterial physiological activities such as growth, metabolism, and signal transduction. (2R,3R)-Butane-2,3-diol mediates bacterial-host cell signaling interactions and affects the metabolic balance of intestinal microorganisms, and can be used to study lactose intolerance and other related diseases^[1]. In Vitro:(2R,3R)-Butane-2,3-diol (100 mM; 1-2 min) significantly induces a rapid increase in intracellular free Ca²⁺ concentration in the Escherichia coli intracellular calcium transient assay, with the peak value increasing by about 1-2 μM compared with the control group, and this effect is dependent on the external Ca²⁺ concentration (0.1-10 mM)^[1].
(2R,3R)-Butane-2,3-diol (5-200 mM; 5 min) activates the E. coli Ca²⁺ channel in a dose-dependent manner in the concentration-dependent assay, with EC₅₀ of about 25 mM. Under the condition of 10 mM external Ca²⁺, the peak intracellular Ca²⁺ could reach 25 μM^[1].