CATH Classification
| Level | CATH Code | Description |
|---|---|---|
|
3 | Alpha Beta |
|
3.40 | 3-Layer(aba) Sandwich |
|
3.40.50 | Rossmann fold |
|
3.40.50.300 | P-loop containing nucleotide triphosphate hydrolases |
Domain Context
CATH Clusters
| Superfamily | P-loop containing nucleotide triphosphate hydrolases |
| Functional Family | Eukaryotic translation initiation factor 5B |
Enzyme Information
| 3.6.5.3 |
Protein-synthesizing GTPase.
based on mapping to UniProt P39730
GTP + H(2)O = GDP + phosphate.
-!- This enzyme comprises a family of proteins involved in prokaryotic as well as eukaryotic protein synthesis. -!- In the initiation factor complex, it is IF-2b (98 kDa) that binds GTP and subsequently hydrolyzes it in prokaryotes. -!- In eukaryotes, it is eIF-2 (150 kDa) that binds GTP. -!- In the elongation phase, the GTP-hydrolyzing proteins are the EF-Tu polypeptide of the prokaryotic transfer factor (43 kDa), the eukaryotic elongation factor EF-1-alpha (53 kDa), the prokaryotic EF-G (77 kDa), the eukaryotic EF-2 (70-110 kDa) and the signal recognition particle that play a role in endoplasmic reticulum protein synthesis (325 kDa). -!- EF-Tu and EF-1-alpha catalyze binding of aminoacyl-tRNA to the ribosomal A-site, while EF-G and EF-2 catalyze the translocation of peptidyl-tRNA from the A-site to the P-site. -!- GTPase activity is also involved in polypeptide release from the ribosome with the aid of the pRFs and eRFs. -!- Formerly EC 3.6.1.48.
|
UniProtKB Entries (1)
| P39730 |
IF2P_YEAST
Saccharomyces cerevisiae S288C
Eukaryotic translation initiation factor 5B
|
PDB Structure
| PDB | 4NCF |
| External Links | |
| Method | X-RAY DIFFRACTION |
| Organism | |
| Primary Citation |
eIF5B employs a novel domain release mechanism to catalyze ribosomal subunit joining.
Embo J.
|