Interaction of fragment A from diphtheria toxin with nicotinamide adenine dinucleotide.
نویسندگان
چکیده
This reaction is catalyzed by Fragment A (mol wt 24,000) or other less common fragments generated by limited proteolysis and reduction of the toxin, but not by the toxin itself (mol wt 63,000). This report describes studies of the interaction of NAD+ with Fragment A. In addition to its major enzymic activity, Fragment A also catalyzes the slow hydrolysis of the nicotinamide-ribose linkage of NAD+.
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NAD-dependent inhibition of protein synthesis by Pseudomonas aeruginosa toxin,.
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The intact diphtheria toxin molecule, a single polypeptide chain of about 62,000 daltons, has no enzymic activity. However, the transfer in uifro of ADP-ribose from NAD to aminoacyltrensferase II can be catalyzed by any of several fragments of toxin. The smallest active fragment (A, 24,000 daltons) is normally connected to the remainder of the molecule (B, 38,000 daltons) by a peptide bond and ...
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ورودعنوان ژورنال:
- The Journal of biological chemistry
دوره 249 7 شماره
صفحات -
تاریخ انتشار 1974