CHIRAL INTERACTION OF A POLYCLONAL ANTI-DINITROPHENYL ANTIBODY WITH DINITROPHENYL AMINO-ACIDS DETERMINED BY AN ENANTIOSELECTIVE ENZYME-LINKED-IMMUNOSORBENT-ASSAY

The enantioselectivity of the interaction of a polyclonal anti-DNP (di nitrophenyl) antiserum with st variety of DNP-amino acids has been det ermined by an indirect noncompetitive ELISA and the results obtained h ave been compared with those of an indirect competitive ELISA. The com petitive ELISA offers an advantage to determine the I-50 values repres enting the relative affinities of the investigated DNP-amino acid enan tiomers. In all cases, the I-50 values obtained were different for the individual DNP-amino acid enantiomers. While the L-enantiomers of eps ilon-DNP-lysine, delta-DNP-ornithine, DNP-alanine and DNP-proline show a higher relative affinity for the antibody combining site than the D -enantiomers, an inverse chiral recognition was found for DNP-phenylal anine. On account of the high sensitivity of the ELISA system, the det ermination of small differences in the enantiomer recognition by the a nti-DNP antibody is possible.