Bacterial 16S ribosomal RNA decoding center (16S rRNA decoding center)

The bacterial 16S ribosomal RNA (rRNA) decoding center is a highly conserved region within the 30S small ribosomal subunit that plays a fundamental role in the fidelity of protein synthesis (Nature Reviews Microbiology, 2014). It is responsible for the accurate selection of aminoacyl-tRNA molecules based on the mRNA codon sequence present at the aminoacyl (A) site (PubMed, PMID: 10731133). During the decoding process, specific adenine residues (A1492 and A1493 in E. coli) flip out of the 16S rRNA helix to monitor the geometry of the codon-anticodon helix, ensuring a correct match (Science, 2001). This site is a major pharmacological target for several classes of antibiotics, including aminoglycosides and tetracyclines (StatPearls, 2023). Aminoglycosides bind directly to the decoding center, stabilizing the flipped-out conformation of the adenine residues and causing the ribosome to accept near-cognate tRNAs, which leads to lethal errors in protein synthesis (Nature, 2000). Because human mitochondrial ribosomes share structural similarities with bacterial 16S rRNA, drugs targeting this site can sometimes cause side effects such as hearing loss and kidney damage (NIH/NCBI, 2022).

Other names

16S rRNA A-site30S ribosomal subunit decoding centerDecoding region of the 30S subunitA-site of the 16S rRNA

Inhibition of bacterial protein synthesis through the induction of mRNA misreading or the physical blockade of aminoacyl-tRNA binding to the ribosomal A-site (Nature, 2000; StatPearls, 2023).