Escherichia coli initiation factor IF3 binding to AUG and AUG-containing single strands and hairpin loops, and nonspecific binding to polymers.

Nitrocellulose filter binding and equilibrium dialysis detected the binding of Escherichia coli initiation factor IF3 to AUG, An UGUm single strands and hairpin loops, poly(A,U,G), poly(U), and f2 RNA. No binding was detected for GUA, A8 U, or the hairpin loop A5 GC5 U5. AUG-specific binding, per nucleotide, is strong; nonspecific binding, per nucleotide, is weak.