Clostridium difficile toxin A (TcdA) is a protein encoded by C. difficile that functions in modifying Ras family GTPases, leading to epithelial cell damage and apoptosis. The encoded gene translates to a 2710-aa protein with a mass of 308 kDa. The N-terminal domain acts in transfering a glucose moiety to target molecules, resulting in signaling pathway inactivation. This enterotoxin is detectable in the supernatant of C. difficile cultures, as well as in patient stool samples.