Bacterial ribosomal inter-subunit bridge B5 (Bridge B5)

The Bacterial ribosomal inter-subunit bridge B5 is a fundamental structural element that facilitates the association between the small (30S) and large (50S) subunits to form the functional 70S ribosome (Yusupov et al., 2001, Science). Located near the decoding center, Bridge B5 is primarily formed by the interaction of helix 44 (h44) of the 16S rRNA with helix 68 (h68) of the 23S rRNA and the ribosomal protein L2 (Dunkle et al., 2011, Science). This bridge is essential for the coordinated conformational changes, such as ratcheting, that occur during the translocation phase of protein synthesis (Wilson, 2014, Nature Reviews Microbiology). Due to its proximity to the A-site and its role in subunit stability, it is a critical site for the action of several classes of antibiotics, most notably aminoglycosides like gentamicin and paromomycin (Vicens & Westhof, 2001, Structure). These drugs bind to the rRNA components of the bridge, leading to misreading of the genetic code or total inhibition of translocation. Consequently, Bridge B5 is a key focal point for understanding bacterial translation and developing treatments for various bacterial infections (Pulk & Cate, 2013, Science).

Other names

Inter-subunit bridge B5B5 bridgeRibosomal bridge B570S inter-subunit bridge B5

Inhibition of protein synthesis by stabilizing the 70S complex, interfering with the movement of mRNA and tRNA, or inducing misreading of the genetic code.