Quantitative Study of the Interaction of Formylmethionyl‐tRNAfMet with Ribosomes of Escherichia coli

fMet-tRNAfMet binds reversibly to the donor site (P-site) of Escherichia coli ribosomes both in the absence of messenger and in the presence of ApUpGp and some other oligonucleotides or poly(U). Kinetics of interaction conforms the second-order law. The equilibrium constants and the rate constants of binding are estimated at 0 degrees C. Not only the cognate trinucleotide ApUpGp but also some other oligonucleotides and even poly(U) stimulate the binding. The presence of total deacylated tRNA considerably increases the selectivity of association.