Correction

Vol. 200, No. 1, July 5, 2004. Pages 35–46.

Due to an arithmetic error, an active site Serine residue at position 272 in the deduced amino acid sequence of the A subunit of the toxin described in this paper was incorrectly stated as being at position 271. This has resulted in incorrect terminology for the critical residue and for mutations introduced at this position, as listed below.

codon 271 should be codon 272 on page 37

S₂₇₁ should be S₂₇₂ on pages 37 and 40

Ser₂₇₁-Ala should be Ser₂₇₂-Ala on page 45

pK184subA_A271B should be pK184subA_A272B throughout

SubA_A271B should be SubA_A272B in Figure 8 B

The residue numbers of the terminal amino acids of the Ser catalytic domain (269 and 279) should be 270 and 280 in Figure 2.