... dehydrogenase from Pto DC3000. Site-directed mutants targeting the catalytic residues Cys 302 and Glu 267 resulted in a loss of enzymatic activity. The X-ray crystal structure of the catalytically inactive AldA C302A mutant in complex with IAA and NAD + showed the cofactor adopting a conformation that differs...

... of 10 −5 M and a 1:1 stoichiometry for the complex. In equilibrium dialysis experiments Cibacron blue behaves as a competitive inhibitor of the binding of NAD to diphtheria toxin fragment A. The dye inhibits in a non-competitive way the fragment A-catalysed transfer of ADP-ribose from NAD to elongation...