SNAP annotations: PDB entry 1hr0

PDB-id

1hr0; DSSR-derived features in text and JSON formats; DNAproDB

Class

ribosome

Method

X-ray (3.2 Å)

Summary

Crystal structure of initiation factor if1 bound to the 30s ribosomal subunit

Reference

Carter AP, Clemons Jr WM, Brodersen DE, Morgan-Warren RJ, Hartsch T, Wimberly BT, Ramakrishnan V (2001): "Crystal structure of an initiation factor bound to the 30S ribosomal subunit." Science, 291, 498-501. doi: 10.1126/science.1057766.

Abstract

Initiation of translation at the correct position on messenger RNA is essential for accurate protein synthesis. In prokaryotes, this process requires three initiation factors: IF1, IF2, and IF3. Here we report the crystal structure of a complex of IF1 and the 30S ribosomal subunit. Binding of IF1 occludes the ribosomal A site and flips out the functionally important bases A1492 and A1493 from helix 44 of 16S RNA, burying them in pockets in IF1. The binding of IF1 causes long-range changes in the conformation of H44 and leads to movement of the domains of 30S with respect to each other. The structure explains how localized changes at the ribosomal A site lead to global alterations in the conformation of the 30S subunit.