Final answer:
Tetracycline does not bind to the 50S ribosomal subunit; it binds to the 30S subunit. Erythromycin and chloramphenicol bind to the 50S subunit and affect protein synthesis.
Step-by-step explanation:
The compound that does not bind to the 50S ribosomal subunit is tetracycline. Antibiotics such as erythromycin, chloramphenicol, and streptomycin have different targets within the bacterial ribosome. Erythromycin is a macrolide that binds to the 50S subunit interfering with protein synthesis. Chloramphenicol also binds to the 50S subunit and prevents peptide bond formation, thereby stopping protein synthesis. Streptomycin, on the other hand, binds to the 30S subunit like tetracyclines but is of a different class, the aminoglycosides. The correct answer to the question, therefore, is c) Tetracycline, which binds to the 30S subunit and blocks the binding of tRNA, inhibiting protein synthesis.