Studies on the Antigenic Structure of Ribonuclease
V. DINITROPHENYLATED RIBONUCLEASE
Ray K. Brown 1, Marijane McEwan 1, Carole A. Mikoryak 1, and Jane Polkowski 1
From the
1 From the Department of Biochemistry, Wayne State University School of Medicine, Detroit, Michigan 48207
Rabbit antibodies to 1-
-dinitrophenylaminoribonuclease, 41-
-dinitrophenylamino-RNase, RNase A, and their oxidized derivatives have been prepared. Only 1--dinitrophenylamino-RNase gives an appreciable decrease in precipitin and complement fixation reactions when compared with the appropriate unlabeled form. The two antisera to 41--dinitrophenylamino-RNase had no antibody to the dinitrophenyl group as judged by cross-reaction and hapten inhibition, and little antibody as estimated by precipitation with dinitrophenylated bovine 
-globulin. All other dinitrophenylated RNase derivatives elicited considerable antibody to the dinitrophenyl group. Perhaps the dinitrophenyl group on lysine 41 is folded into the interior. The binding constants are heterogeneous for the interaction between -14C-dinitrophenyllysine and antibody to oxidized 41--dinitrophenylamino-RNase.
Although both monomeric and dimeric RNase precipitate equal amounts of antibody when the reaction is carried out in small volumes, 1.5 to 2 times as much antigen on a nitrogen basis is required to reach equivalence when dimer is used. In precipitin studies with 41--14C-dinitrophenylamino-RNase monomer and dimer, the ratio of antibody to antigen was 2.00 ± 0.06 with monomer and varied from 1.71 in antibody excess to 1.28 in antigen excess with dimer. Certain antigenic sites are less reactive or decreased in concentration in the dimer.
Submitted on October 14, 1966
CiteULike 
Complore 
Connotea 
Del.icio.us 
Digg 
Reddit 
Technorati What's this?
