One of the primary rRNA binding proteins. Required for association of the 30S and 50S subunits to form the 70S ribosome, for tRNA binding and peptide bond formation. It has been suggested to have peptidyltransferase activity; this is somewhat controversial. Makes several contacts with the 16S rRNA in the 70S ribosome. Part of the 50S ribosomal subunit. Forms a bridge to the 30S subunit in the 70S ribosome. The initiator methionine may be removed. Belongs to the universal ribosomal protein uL2 family.