Photolabile antibiotics as probes of ribosomal structure and function

In summary, our studies have resulted in the development of new reagents and synthetic procedures for the introduction of both radioactivity and photolability into antibiotics; have provided examples of how PAGE analysis can be used to conveniently test various aspects of photoaffinity labeling of complex receptors, such as the ribosome; have revealed examples of unexpected photoreactivity, as in the case of puromycin; and have provided strong evidence regarding the three-dimensional location of the peptidyl transferase center and the site of that interaction of the 3' and of aminoacyl-tRNA with the 30S subunit. Work that is now in progress should provide similar detailed information regarding other functional sites in the ribosome.