Cloned (Comment) | Organism |
---|---|
recombinant expression of nontagged wild-type full-length enzyme in Escherichia coli strain BL21(DE3) and of selenomethionine-labelled enzyme in Escherichia coli strain B834 (DE3) | Thermus thermophilus |
Crystallization (Comment) | Organism |
---|---|
purified recombinant apoenzyme protein core and enzyme in complex with GTP or GDP, sitting-drop vapour diffusion method, mixing of protein in 20 mM HEPES, pH 7.5, 50 mM KCl, 20 mM MgCl2, 1 mM DTT, with 2.5% glycerol and with reservoir solution containing 20% PEG 3350 and 0.2 M ammonium nitrate, to a final volume of 0.008 ml, 21°C, 1-3 weeks, X-ray diffraction structure determination and analysis | Thermus thermophilus |
Metals/Ions | Comment | Organism | Structure |
---|---|---|---|
Mg2+ | required, binding tructure analysis | Thermus thermophilus |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
GTP + H2O | Thermus thermophilus | - |
GDP + phosphate | - |
? | |
GTP + H2O | Thermus thermophilus HB8 / ATCC 27634 / DSM 579 | - |
GDP + phosphate | - |
? |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Thermus thermophilus | P48515 | - |
- |
Thermus thermophilus HB8 / ATCC 27634 / DSM 579 | P48515 | - |
- |
Purification (Comment) | Organism |
---|---|
recombinant wild-type and selenomethionine-labelled enzymes from Escherichia coli by hydrophobic interaction chromatography | Thermus thermophilus |
Reaction | Comment | Organism | Reaction ID |
---|---|---|---|
GTP + H2O = GDP + phosphate | conformational changes of the protein upon nucleotide binding, in particular in the P-loop region, which extend to the functionally relevant switch II region. The latter carries a catalytically important and conserved histidine residue which is observed in different conformations in the GTP and GDP complexes. Activation of GTP hydrolysis may occur by a conformational repositioning of the histidine residue | Thermus thermophilus |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
GTP + H2O | - |
Thermus thermophilus | GDP + phosphate | - |
? | |
GTP + H2O | molecular recognition in the GTP-binding site, overview | Thermus thermophilus | GDP + phosphate | - |
? | |
GTP + H2O | - |
Thermus thermophilus HB8 / ATCC 27634 / DSM 579 | GDP + phosphate | - |
? | |
GTP + H2O | molecular recognition in the GTP-binding site, overview | Thermus thermophilus HB8 / ATCC 27634 / DSM 579 | GDP + phosphate | - |
? |
Subunits | Comment | Organism |
---|---|---|
trimer | - |
Thermus thermophilus |
Synonyms | Comment | Organism |
---|---|---|
IF2 | - |
Thermus thermophilus |
translation initiation factor 2 | - |
Thermus thermophilus |
pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
---|---|---|---|
7.5 | - |
assay at | Thermus thermophilus |
General Information | Comment | Organism |
---|---|---|
additional information | conformational changes of enzyme IF2 upon nucleotide binding control switches I and II in the G domain, modeling, overview | Thermus thermophilus |
physiological function | the translation initiation factor 2 (IF2) is involved in the early steps of bacterial protein synthesis. It promotes the stabilization of the initiator tRNA on the 30S initiation complex and triggers GTP hydrolysis upon ribosomal subunit joining | Thermus thermophilus |