Clostridioides difficile toxin A glucosyltransferase domain (TcdA-GTD)

The Clostridioides difficile toxin A glucosyltransferase domain (TcdA-GTD) is the N-terminal catalytic component of Toxin A, a major virulence factor produced by the bacterium Clostridioides difficile [1, 2]. This domain is responsible for the toxin's intracellular activity, specifically the monoglucosylation of host Rho family GTPases such as Rho, Rac, and Cdc42 [1]. By utilizing UDP-glucose as a sugar donor, the GTD covalently modifies these signaling proteins, leading to the disruption of the actin cytoskeleton, loss of cell-cell junctions, and eventual cell death [2, 4]. This process results in the characteristic mucosal damage and inflammation seen in Clostridioides difficile infections (CDI), which range from mild diarrhea to life-threatening pseudomembranous colitis [3]. As a critical driver of pathogenesis, the TcdA-GTD is a major target for therapeutic intervention, including neutralizing monoclonal antibodies like actoxumab and experimental small-molecule inhibitors designed to block its enzymatic activity [3, 4]. Understanding the structural biology of this domain is crucial for developing next-generation therapeutics that can mitigate the symptoms of pseudomembranous colitis and reduce CDI recurrence [2, 3].

Other names

TcdA GTDClostridium difficile toxin A glucosyltransferase domainTcdA(1-542)Glucosyltransferase domain of TcdATcdA catalytic domain

Neutralization of toxin activity or direct inhibition of the glucosyltransferase enzymatic activity to prevent Rho GTPase inactivation.