Figure 5.

Crosslinking of sparsomycin derivatives (50 μM) to E. coli 70S ribosomes.poly(U) complexes in the presence and absence of N-Ac-Phe-tRNA. (A) Benzyl-sparsomycin (B-Spa). (B) Pentyl-sparsomycin (P-Spa). (C) Octyl-sparsomycin (O-Spa). (D) Phenol-alanine-sparsomycin (Pa-Spa). The structures of the derivatives are given in Fig. 1. Complexes were formed and irradiated at 365 nm for 20 min and were analyzed by primer extension (see Material and Methods). G, A, U, and C denote sequencing tracks.