Conduritol aziridine: a new mechanism-based glucosidase inactivator

A new mechanism-based glucosidase inactivator, conduritol aziridine (1,2-dideoxy-1,2-epimino-myo-inositol), has been synthesised from myo-inositol. This aziridine inactivates both the beta-glucosidase from Alcaligenes faecalis and the alpha-glucosidase from yeast according to the expected pseudo-first order kinetics. Inactivation constants measured are Ki = 3.0mM, ki = 0.077 min-1 for the beta-glucosidase, and Ki = 9.5mM, ki = 0.39 min-1 for the alpha-glucosidase. Evidence for irreversible inactivation is provided by the lack of reactivation upon dilution of inactivated enzyme into buffer containing substrate.