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1ml5
From Proteopedia
| 1ml5, resolution 14.00Å () | |||||||||
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| Non-Standard Residues: | , , , , , , , , , , | ||||||||
| Gene: | prfB/SupK (Escherichia coli) | ||||||||
| Related: | 1gqe, 1dt9, 1gix, 1giy | ||||||||
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| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||||
Contents |
Structure of the E. coli ribosomal termination complex with release factor 2
Termination of protein synthesis occurs when the messenger RNA presents a stop codon in the ribosomal aminoacyl (A) site. Class I release factor proteins (RF1 or RF2) are believed to recognize stop codons via tripeptide motifs, leading to release of the completed polypeptide chain from its covalent attachment to transfer RNA in the ribosomal peptidyl (P) site. Class I RFs possess a conserved GGQ amino-acid motif that is thought to be involved directly in protein-transfer-RNA bond hydrolysis. Crystal structures of bacterial and eukaryotic class I RFs have been determined, but the mechanism of stop codon recognition and peptidyl-tRNA hydrolysis remains unclear. Here we present the structure of the Escherichia coli ribosome in a post-termination complex with RF2, obtained by single-particle cryo-electron microscopy (cryo-EM). Fitting the known 70S and RF2 structures into the electron density map reveals that RF2 adopts a different conformation on the ribosome when compared with the crystal structure of the isolated protein. The amino-terminal helical domain of RF2 contacts the factor-binding site of the ribosome, the 'SPF' loop of the protein is situated close to the mRNA, and the GGQ-containing domain of RF2 interacts with the peptidyl-transferase centre (PTC). By connecting the ribosomal decoding centre with the PTC, RF2 functionally mimics a tRNA molecule in the A site. Translational termination in eukaryotes is likely to be based on a similar mechanism.
Structure of the Escherichia coli ribosomal termination complex with release factor 2., Klaholz BP, Pape T, Zavialov AV, Myasnikov AG, Orlova EV, Vestergaard B, Ehrenberg M, van Heel M, Nature. 2003 Jan 2;421(6918):90-4. PMID:12511961
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
About this Structure
1ml5 is a 45 chain structure with sequence from Escherichia coli. Full crystallographic information is available from OCA.
See Also
- Ribosomal protein L1
- Ribosomal protein L11
- Ribosomal protein L13
- Ribosomal protein L14
- Ribosomal protein L15
- Ribosomal protein L16
- Ribosomal protein L18
- Ribosomal protein L19
- Ribosomal protein L2
- Ribosomal protein L22
- Ribosomal protein L23
- Ribosomal protein L24
- Ribosomal protein L25
- Ribosomal protein L29
- Ribosomal protein L3
- Ribosomal protein L30
- Ribosomal protein L4
- Ribosomal protein L5
- Ribosomal protein L6
- Ribosomal protein S10
- Ribosomal protein S11
- Ribosomal protein S12
- Ribosomal protein S13
- Ribosomal protein S14
- Ribosomal protein S15
- Ribosomal protein S16
- Ribosomal protein S17
- Ribosomal protein S18
- Ribosomal protein S19
- Ribosomal protein S2
- Ribosomal protein S20
- Ribosomal protein S3
- Ribosomal protein S4
- Ribosomal protein S5
- Ribosomal protein S6
- Ribosomal protein S7
- Ribosomal protein S8
- Ribosomal protein S9
- Ribosomal protein THX
Reference
- Klaholz BP, Pape T, Zavialov AV, Myasnikov AG, Orlova EV, Vestergaard B, Ehrenberg M, van Heel M. Structure of the Escherichia coli ribosomal termination complex with release factor 2. Nature. 2003 Jan 2;421(6918):90-4. PMID:12511961 doi:10.1038/nature01225
