86 IMMUNO-CATALYSIS 



we must therefore confine our ideas for the time being to the realm 

 of possibilities. 



With these limitations in mind, the theories advanced concerning 

 the mechanism of antibody formation are discussed below. 



3. Mechanism of Antibody Formation 



(a) Breinl and Haurowitz (1930), (b) Mudd (1932), (c) Alex- 

 ander (1931), (d) Pauling (1940) and others have offered hypotheses 

 on the possible mechanism of antibody formation. 



a. The Theory of Breinl and Haurowitz. These authors assume 

 that the cells which synthesize serum globulin possess species specific 

 surfaces containing certain groups with residual valences which attract 

 or repulse amino acids participating in the formation of globulin. An 

 antigen combining with these surfaces produces new groups of differ- 

 ent residual valences. The orientation of amino acids in the formation 

 of antibody globulin are thus governed by surface valences of the 

 new cell-antigen complex. Possible evidence concerning the presence 

 of surface valences are cited from the observations of Landsteiner 

 that only those antigens containing groups with weak residual valences, 

 such as -COOH, -NHo, -HSO3, etc. show antibody determining 

 property whereas aliphatic (paraffin) chains, or plain aromatic rings, 

 which lack such residual valences, are devoid of antibody forming 

 property. 



b. The Theory of Mudd. Mudd bases his concept of the mechanism 

 of antibody formation on the specific relationship between antigen and 

 antibody. The striking instances cited by him are the d- and 1- 

 tartranilic acid azo-proteins of Landsteiner and van der Scheer (1929) 

 and the p-amino-phenol-i8-glucoside and p-amino-phenol-^-galactoside 

 azoproteins of Avery and Goebel (1929). Injected into rabbits they 

 give rise to antibodies which combine electively with the particular 

 stereoisomer injected. Synthesis by the linking of amino acids to the 

 peptide is supposed to occur in an orienting environment, namely the 

 antigen-protoplasm interface. The chemical groupings linked to the 

 molecule undergoing synthesis at the antigen surface are believed to 

 be adapted spatially and in their chemical affinities to the antigen 

 surface at the region in which linkage occurs. The synthesized anti- 

 body molecule should therefore possess to some degree a stereochemical 



