Identification of the amino acid functional groups responsible for 30-S ribosome recognition of messenger RNA.

About 30 protein-selective chemical reagents have been tested for their ability to inhibit the mRNA binding activity of the 30-S ribosome. A number of reagents were investigated which have been shown by other workers to be capable of modifying free epsilon-amino groups of lysine and all were found to inactivate 30-S ribosomes completely for natural mRNA binding activity. Several reagents selective for histidine, tyrosine, and tryptophan were also found to inactivate. We suggest that the epsilon-amino groups of lysine play an important role in mRNA binding to the 30-S ribosome.