Cloned (Comment) | Organism |
---|---|
gene inB, recombinant expression in Escherichia coli strain BL21infB::kanR, that has an inactivated endogenous infB gene | Escherichia coli |
Protein Variants | Comment | Organism |
---|---|---|
E571K | the IF2alpha mutant has a completely inactivated GTPase activity | Escherichia coli |
additional information | construction of a IF2alphaDELTA GTPase mutant with abolished GTPase activity | Escherichia coli |
Localization | Comment | Organism | GeneOntology No. | Textmining |
---|---|---|---|---|
ribosome | - |
Escherichia coli | 5840 | - |
Metals/Ions | Comment | Organism | Structure |
---|---|---|---|
Mg2+ | required | Escherichia coli |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
GTP + H2O | Escherichia coli | - |
GDP + phosphate | - |
? |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Escherichia coli | P0A705 | - |
- |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
GTP + H2O | - |
Escherichia coli | GDP + phosphate | - |
? | |
additional information | IF2 has protein chaperone activity. It catalyzes the refolding of heat-denatured GFP upon incubation for 8 min at 25°C at chaperone/GFP stoichiometric ratios of 1:1 carried out in buffer containing 1 mM GTP and 1 mM ATP. IF2alpha displays the highest chaperone activity in the presence of GTP, and its activity is substantially reduced, albeit not completely abolished, in the presence of GDP, or of the non-hydrolysable analogue GDPCP or in the absence of guanine nucleotides | Escherichia coli | ? | - |
- |
Synonyms | Comment | Organism |
---|---|---|
IF2 | - |
Escherichia coli |
IF2alpha | - |
Escherichia coli |
infB | - |
Escherichia coli |
translation initiation factor | - |
Escherichia coli |
Temperature Optimum [°C] | Temperature Optimum Maximum [°C] | Comment | Organism |
---|---|---|---|
17 | - |
chaperone activity assay at | Escherichia coli |
25 | - |
GTPase assay at | Escherichia coli |
pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
---|---|---|---|
7.5 | - |
assay at | Escherichia coli |
Organism | Comment | Expression |
---|---|---|
Escherichia coli | cold stress in Escherichia coli induces de novo synthesis of translation initiation factors IF1, IF2 and IF3 while ribosome synthesis and assembly slow down | up |
General Information | Comment | Organism |
---|---|---|
malfunction | two cold-sensitive IF2 mutations cause the accumulation of immature ribosomal particles | Escherichia coli |
metabolism | IF1 and IF3 increase plays a role in translation regulation at low temperature (cold-shock-induced translational bias) while the increase in IF2 made after cold stress is associated with immature ribosomal subunits together with at least another nine proteins involved in assembly and/or maturation of ribosomal subunits. IF2 is endowed with GTPase-associated chaperone activity that promotes refolding of denatured GFP | Escherichia coli |
physiological function | translation initiation factor IF2 contributes to ribosome assembly and maturation during cold adaptation. IF2 is endowed with GTPase-associated chaperone activity that promotes refolding of denatured GFP. IF2 is another GTPase protein that participates in ribosome assembly/maturation, especially at low temperatures, the GTPase activity takes part in the assembly and maturation of the ribosomal subunits. The functional role of IF2 cannot be regarded as being restricted to its well documented functions in translation initiation of bacterial mRNA. IF2 has protein chaperone activity. For assembly and maturation of the ribosomal subunits, the cell requires an increased number of IF2 molecules, it is essential during the cold acclimation phase which follows cold stress when this process becomes particularly critical | Escherichia coli |