FIG. 1.

Secondary structure of helix 34 of 16S rRNA of E. coli. The location of the G→C mutation at position 1058 associated with tetracycline resistance is indicated, as is the position of the cross-link of U1052 to the 3′ base of the A-site codon (5). Tet indicates bases whose reactivities to chemical attack are enhanced by tetracycline (16). The CG base pair, C1051 and G1207, which is not conserved between E. coli and cutaneous propionibacteria is indicated.