ADP-RIBOSYLATION OF A(1) PEPTIDE OF CHOLERA-TOXIN BY CHICKEN ARGININE-SPECIFIC ADP-RIBOSYLTRANSFERASE WITH A CONCOMITANT INCREASE IN ADP-RIBOSYLTRANSFERASE ACTIVITY OF THE PEPTIDE

We studied the in vitro ADP-ribosylation of the A1 peptide of cholera toxin by arginine-specific ADP-ribosyltransferase purified from chicke n peripheral polymorphonuclear leukocytes. Chicken ADP-ribosyltransfer ase modified A1 peptide, but not the entire toxin. Four moles of ADP-r ibose were incorporated into 1 mol of A1 peptide. Modification of A1 p eptide increased its enzymic activity up to 4-fold, as demonstrated by zymographic analysis using poly(L-arginine) as an acceptor.