Serological differentiation of steric isomers (antigens containing tartaric acids): Second paper

Abstract

The experiments reported confirm the results of our previous studies and demonstrate again the striking influence of the steric constitution tin the details given for the tests in a previous paper (1), Table IV c, it should read "0.5 miUimol in 10 cc." on serological properties. It would seem that in this respect the specificity of serum reactions is analogous to that of ferments. However, while in the investigations with ferments one is limited to those found in nature, by our method antibodies can be produced at will, which act on chosen substances. In particular one sees that the change in the spatial configuration with regard to one asymmetric carbon atom is sufficient to cause a pronounced serological difference, as appears from a comparison of the reactions of either the l- or d-antigen with those of the m-antigen. Since the change of the levo- into the dextro-acid would involve a rearrangement of the groups around both asymmetric carbon atoms one may suppose that there is a greater serological difference between these two acids than between either and the m-tartaric acid. This reasoning is supported by the fact that the l-immune sera showed almost no reactions on the d-antigen and vice versa while there were weak group reactions of the l- and d-immune sera with the m-antigen. A question which requires further investigation is whether the marked serological distinction between steric isomers depends on the nature of the radicals connected with the asymmetric carbon atom, i.e., whether any radical will produce an effect of the same order as polar groups like COOH or OH (c.f. Reiner (5)). © 1929, Rockefeller University Press., All rights reserved.