Identification of a single amino acid substitution in the diphtheria toxin A chain of CRM 228 responsible for the loss of enzymatic activity.
نویسندگان
چکیده
CRM 228 (T. Uchida, A. M. Pappenheimer, and R. Greany, J. Biol. Chem. 248:3838-3844, 1973), a mutant form of diphtheria toxin which completely lacks ADP-ribosyltransferase activity, contains five amino acid substitutions. The two amino acid changes that fall within the A chain of the toxin (G79D and E162K) were separately analyzed by substituting a variety of other amino acids at these sites. The substitution at position 79 (G79D) singularly appears to account for the loss of enzymatic activity found in CRM 228.
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ورودعنوان ژورنال:
- Journal of bacteriology
دوره 176 15 شماره
صفحات -
تاریخ انتشار 1994