Site-directed mutagenic alteration of potential active-site residues of the A subunit of Escherichia coli heat-labile enterotoxin. Evidence for a catalytic role for glutamic acid 112.

Site-directed mutagenic alteration of potential active-site residues of the A subunit of Escherichia coli heat-labile enterotoxin. Evidence for a catalytic role for glutamic acid 112.