[Possible mechanism of specific protein-nucleic acid interaction]

It has been supposed that stereochemical fitness of amino acids into the cavities associated with their codons is used for specific recognition of nucleic acids by the proteins. In accordance with this hypothesis, amino acid side chains can insert into the cavity resulting from inverting the middle base of a nucleotide triplet in DNA. Certain experimental data seem to support the hypothesis. A model of specific binding between cro-protein from bacteriophage lambda with OR3 operator region of the bacteriophage has been proposed on the basis of the above hypothesis.