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Information on EC 3.6.5.3 - protein-synthesizing GTPase
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3.6.5.3 protein-synthesizing GTPaseIUBMB Comments
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 hydrolyses it in prokaryotes. In eukaryotes, it is eIF-2 (150 kDa) that binds GTP. In the elongation phase, the GTP-hydrolysing proteins are the EF-Tu polypeptide of the prokaryotic transfer factor (43 kDa), the eukaryotic elongation factor EF-1alpha (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-1alpha catalyse binding of aminoacyl-tRNA to the ribosomal A-site, while EF-G and EF-2 catalyse 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.
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Word Map
- 3.6.5.3
- gdp
- actin
- aminoacyl-trnas
-
spacers
- rrna
-
1-alpha
- clade
-
perk
- fusarium
- reticulocyte
- cytoskeleton
-
aminoacylated
- guanosine
-
gtp-binding
- p-tefb
-
alpha-subunit
-
adp-ribosylation
- rapamycin
-
chop
-
rna-dependent
- thermus
-
conidia
-
pausing
- polysomes
-
autophosphorylation
-
stall
-
beta-tubulin
-
monophyletic
-
decoding
- dextrose
-
gdp-bound
- oxysporum
- sh2
-
interferon-induced
-
parsimony
-
anticodons
-
genorm
-
tyrosine-phosphorylated
-
gtp-dependent
- rgs
-
p21ras
-
reisolated
-
normfinder
-
preinitiation
- neurofibromatosis
- artemia
- rnapii
-
cryo-em
- medicine
-
c-gamma
- caspase-12
The expected taxonomic range for this enzyme is: Eukaryota, Bacteria, Archaea
Synonyms
elongation factor, gtpase-activating protein, eif2alpha, elongation factor tu, eif2b, eef1a, ef-1alpha, eukaryotic initiation factor 2, elongation factor g, elongation factor 1 alpha, 
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SYNONYM 
ORGANISM
UNIPROT
COMMENTARY 
LITERATURE
aEF-1alpha
aIF2
archaeal initiation factor 2
EC 3.6.1.48
-
-
formerly
-
EF-1alpha
EF-G
EF-like GTPase
EF-Tu
EF4
EFL
eIF2
eIF5B
elongation factor (EF)
-
-
-
-
elongation factor 1 alpha
elongation factor 1alpha
elongation factor 4
elongation factor G
elongation factor Tu
GTP phosphohydrolase
-
-
-
-
GTPase
-
-
-
-
GTPase HflX
guanine triphosphatase
-
-
-
-
guanosine 5'-triphosphatase
-
-
-
-
guanosine triphosphatase
-
-
-
-
HflX GTPase
IF2
IF2 GTPase
IF3
initiation factor (IF)
-
-
-
-
initiation factor 2
initiation factor 3
L11
LepA
peptide-release or termination factor
-
-
-
-
protein-sythesizing GTPase
ribosomal GTPase
-
-
-
-
ribosome-dependent GTPase
SsEF-1alpha
SsGBP
SSO0269
SSO0412
SSO1050
SSO2381
SsoHflX
translation initiation factor 2
translation initiation factor 2 gamma
translation initiation factor IF2
EF-like GTPase
-
a class of eukaryotic GTPase with a punctate distribution suggesting multiple functional replacements of translation elongation factor 1alpha
EF-like GTPase
-
a class of eukaryotic GTPase with a punctate distribution suggesting multiple functional replacements of translation elongation factor 1alpha
EF-like GTPase
-
a class of eukaryotic GTPase with a punctate distribution suggesting multiple functional replacements of translation elongation factor 1alpha
EF-like GTPase
-
a class of eukaryotic GTPase with a punctate distribution suggesting multiple functional replacements of translation elongation factor 1alpha
EF-like GTPase
-
a class of eukaryotic GTPase with a punctate distribution suggesting multiple functional replacements of translation elongation factor 1alpha
EF-like GTPase
-
a class of eukaryotic GTPase with a punctate distribution suggesting multiple functional replacements of translation elongation factor 1alpha
EF-like GTPase
-
a class of eukaryotic GTPase with a punctate distribution suggesting multiple functional replacements of translation elongation factor 1alpha
EF-like GTPase
-
a class of eukaryotic GTPase with a punctate distribution suggesting multiple functional replacements of translation elongation factor 1alpha
EF-like GTPase
-
a class of eukaryotic GTPase with a punctate distribution suggesting multiple functional replacements of translation elongation factor 1alpha
EF-like GTPase
-
a class of eukaryotic GTPase with a punctate distribution suggesting multiple functional replacements of translation elongation factor 1alpha
EF-like GTPase
-
a class of eukaryotic GTPase with a punctate distribution suggesting multiple functional replacements of translation elongation factor 1alpha
EF-like GTPase
Pleodorina sp.
-
a class of eukaryotic GTPase with a punctate distribution suggesting multiple functional replacements of translation elongation factor 1alpha
EF-like GTPase
-
a class of eukaryotic GTPase with a punctate distribution suggesting multiple functional replacements of translation elongation factor 1alpha
EF-like GTPase
-
a class of eukaryotic GTPase with a punctate distribution suggesting multiple functional replacements of translation elongation factor 1alpha
elongation factor 1alpha
-
-
elongation factor G
-
-
SsEF-1alpha
-
-
SsEF-1alpha
amino acid at position 15, strain MT3 valine, SsMT3EF-1alpha, strain MT4 isoleucine, SsMT4EF-1alpha
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REACTION
REACTION DIAGRAM
COMMENTARY
ORGANISM
UNIPROT
LITERATURE
GTP + H2O = 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 (98kDa) that binds GTP and subsequently hydrolyses it in prokaryotes. in eukaryotes, it is eIF-2 (150 kDa) that binds GTP. In the elongation phase, the GTP-hydrolysing proteins are the EF-Tu polypeptide of the prokaryotic transfer factor (43 kDa), the eukaryotic elongation factor EF-1a (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-1a catalyse binding of aminoacyl-tRNA to the ribosomal A-site, while EF-G and EF-2 catalyse the translocation of peptidyl-tRNA from the A-side to the P-side. GTPase activity is also involved in polypeptide release from the ribosome with the aid of the pRFs and eRFs
-
-
-
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
-
GTP + H2O = GDP + phosphate
catalytic mechanism, structure-function relationship, overview
-
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 HB8 / ATCC 27634 / DSM 579
-
-
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REACTION TYPE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
hydrolysis
hydrolysis of phosphoric ester
additional information
hydrolysis of phosphoric ester
-
-
-
-
hydrolysis of phosphoric ester
-
-
additional information
-
influence on translation initiation pathway and ribosomal subunit joining
additional information
-
anti-association activity for splitted 70S ribosomes subunits; together with ribosome recycling factor and GTP transient split of 70S ribosomes into subunits
additional information
-
anti-association activity for splitted 70S ribosomes subunits; together with ribosome recycling factor and GTP transient split of 70S ribosomes into subunits
-
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SYSTEMATIC NAME
IUBMB Comments
GTP phosphohydrolase (mRNA-translation-assisting)
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 hydrolyses it in prokaryotes. In eukaryotes, it is eIF-2 (150 kDa) that binds GTP. In the elongation phase, the GTP-hydrolysing proteins are the EF-Tu polypeptide of the prokaryotic transfer factor (43 kDa), the eukaryotic elongation factor EF-1alpha (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-1alpha catalyse binding of aminoacyl-tRNA to the ribosomal A-site, while EF-G and EF-2 catalyse 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.
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CAS REGISTRY NUMBER
COMMENTARY
9059-32-9
-
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SUBSTRATE
PRODUCT
REACTION DIAGRAM
ORGANISM
UNIPROT
COMMENTARY
(Substrate)
(Substrate)
LITERATURE
(Substrate)
(Substrate)
COMMENTARY
(Product)
(Product)
LITERATURE
(Product)
(Product)
Reversibility
r=reversible
ir=irreversible
?=not specified
r=reversible
ir=irreversible
?=not specified
2',3'-O-N'-methylanthranilate-GTP + H2O
2',3'-O-N'-methylanthranilate-GDP + phosphate
-
2',3'-O-N'-methylanthranilate, i.e. mant, is attached to GTP. EF-G binds and efficiently hydrolyzes mant-GTP in a ribosome-dependent manner
-
-
?
GTP gamma-(p-azido)anilide + H2O
GDP + phosphoric acid p-azidoanilin
-
-
-
?
GTP + H2O
?
-
70S ribosome, ribosome recycling factor, EF-G, GTP, 30°C, 15 min
-
-
r
GTP + H2O
?
-
70S ribosome, ribosome recycling factor, EF-G, GTP, 30°C, 15 min
-
-
r
GTP + H2O
GDP + phosphate
-
-
-
-
?
GTP + H2O
GDP + phosphate
-
IF2 in complex with GTP, but not GDP promotes fast association of ribosomal subunits during initiation. IF2 promotes fast formation of the first peptide bond in the presence of GTP, but not GDP. GTP form of IF2 accelerates formation of the 70S ribosome from subunits and GTP hydrolysis accelerates release of IF2 from the 70S ribosome
-
-
?
GTP + H2O
GDP + phosphate
-
importance of GTP hydrolysis in translation initiation for optimal cell growth
-
-
?
GTP + H2O
GDP + phosphate
-
release of peptide promoted by the GGQ motif of class 1 release factors regulates the GTPase activity of RF3. Binding of GTP to RF3 and GTP hydrolysis requires peptide chain release
-
-
?
GTP + H2O
GDP + phosphate
-
the catalytic role of His84 in elongation factor Tu is to stabilize the transition state of GTP hydrolysis by hydrogen bonding to the attacking water molecule or, possibly, the gamma-phosphate group of GTP
-
-
?
GTP + H2O
GDP + phosphate
-
the integrity of the path between the peptidyltransferase center and both GTPase-associated center and sarcin-ricin loop is important for EF-G binding
-
-
?
GTP + H2O
GDP + phosphate
-
reaction using Escherichia coli 70S ribosomes, determination of binding of GTPases to 70S ribosomes in the GTP state, formation of 70S ribosome-tRNAPhe -GTPase-GDPNP complexes, multiple-turnover GTP hydrolysis
-
-
?
GTP + H2O
GDP + phosphate
-
reaction using Escherichia coli 70S ribosomes, determination of binding of GTPases to 70S ribosomes in the GTP state, formation of 70S ribosome-tRNAPhe -GTPase-GDPNP complexes, multiple-turnover GTP hydrolysis
-
-
?
GTP + H2O
GDP + phosphate
-
extodomain 2+3 stimulate the GTPase activity of ectodomain 1
-
-
?
GTP + H2O
GDP + phosphate
-
extodomain 2+3 suppress the GTPase activity of ectodomain 1
-
-
?
GTP + H2O
GDP + phosphate
-
GTPase activation due to C domain of the translation termination factor eRF1, which is bound with translation termination factor eRF3. As for the M and N domains, stimulation of eRF3 GTPase activity is more likely associated with the former, which is located in the large subunit along with the GTPase center of the ribosome, than with the latter, which is oriented towards the decoding center located in the small ribosomal subunit
-
-
?
GTP + H2O
GDP + phosphate
-
the selenocysteine tRNA-specific elongation factor is responsible for the cotranslational incorporation of selenocysteine into proteins by recoding of a UGA step codon in the presence of a downstream mRNA hairpin loop
-
-
?
GTP + H2O
GDP + phosphate
-
two models of the reaction mechanism using the crystal structure: I. Glu81 becomes protonated upon GTP binding, with preference to bind GDP apparently contradicting its assignment as ON, or II. Glu81 protonation/deprotonation defines the ON/OFF states. Protonated Glu81, is ON, whereas X-ray(GTP):GDP is OFF. The model postulates that distant conformational changes such as domain IV rotation are uncoupled from GTP/GDP exchange and do not affect the relative GTP/GDP binding affinities. Glu81-GTP interaction helps to hold switch 2 in place, if Glu81 is deprotonated, it and nearby residues move away from their crystal positions
-
-
?
GTP + H2O
GDP + phosphate
-
-
-
-
?
GTP + H2O
GDP + phosphate
-
ribosome-dependent GTPase strongly stimulates the binding of initiator tRNA to the ribosomes even in the absence of other factors
-
-
?
GTP + H2O
GDP + phosphate
-
aIF2/5B enhances the translation of both leadered and leaderless mRNAs when expressed in a cell-free protein-synthesizing system
-
-
?
GTP + H2O
GDP + phosphate
ATP hydrolysis is insignificant compared to the levels of GTP hydrolysis
-
-
?
GTP + H2O
GDP + phosphate
-
displays either the intrinsic or the ribosome-dependent GTPase activity
-
-
?
GTP + H2O
GDP + phosphate
-
slow GTPase with relatively low affinity for GTP
-
-
?
GTP + H2O
GDP + phosphate
ATP hydrolysis is insignificant compared to the levels of GTP hydrolysis
-
-
?
GTP + H2O
GDP + phosphate
-
slow GTPase with relatively low affinity for GTP
-
-
?
GTP + H2O
GDP + phosphate
-
the enzyme has the same domain structure and biochemical properties of a typical IF2 species as found in bacteria or mammalian mitochondria, but with enhanced ability to bind unformylated initiator met-tRNA
-
-
?
GTP + H2O
GDP + phosphate
-
-
-
?
GTP + H2O
GDP + phosphate
-
mutant of elongation factor G containing the effector loop from Thermus aquaticus EF-Tu has markedly decreased GTPase activity and does not catalyze translocation. The loops are not functionally interchangeable since the factors interact with different states of the ribosome
-
-
?
GTP + H2O
GDP + phosphate
-
Base A 2660 is crucial for GTPase activity of EF-G. Reaction rates using reconstituted ribosomes, single turnover measurement, overview
-
-
?
GTP + H2O
GDP + phosphate
-
mutant of elongation factor G containing the effector loop from Thermus aquaticus EF-Tu has markedly decreased GTPase activity and does not catalyze translocation. The loops are not functionally interchangeable since the factors interact with different states of the ribosome
-
-
?
GTP + H2O
GDP + phosphate
-
elongation factor G catalyzes the translocation step in protein synthesis on the ribosome
-
-
?
GTP + H2O
GDP + phosphate
-
enzyme-GTP and enzyme-GDP conformations in solution are very similar. The major contribution to the active GTPase conformation, which is quite different, therefore comes from its interaction with the ribosome
-
-
?
GTP + H2O
GDP + phosphate
-
EF-Tu is in its active conformation, when the switch I loop is ordered, and the catalytic histidine is coordinating the nucleophilic water in position for inline attack on the gamma-phosphate of GTP. The activated conformation is achieved due to a critical and conserved interaction of the histidine with A2662 of the sarcin-ricin loop of the 23S ribosomal RNA. Universal mechanism for GTPase activation and hydrolysis in translational GTPases on the ribosome. Premature GTP hydrolysis in EF-Tu is prevented by a hydrophobic gate consisting of residues Val20 of the P loop and Ile60 of switch I, which restricts access of His84 to the catalytic water
-
-
?
GTP + H2O
GDP + phosphate
molecular recognition in the GTP-binding site, overview
-
-
?
GTP + H2O
GDP + phosphate
Thermus thermophilus HB8 / ATCC 27634 / DSM 579
-
EF-Tu is in its active conformation, when the switch I loop is ordered, and the catalytic histidine is coordinating the nucleophilic water in position for inline attack on the gamma-phosphate of GTP. The activated conformation is achieved due to a critical and conserved interaction of the histidine with A2662 of the sarcin-ricin loop of the 23S ribosomal RNA. Universal mechanism for GTPase activation and hydrolysis in translational GTPases on the ribosome. Premature GTP hydrolysis in EF-Tu is prevented by a hydrophobic gate consisting of residues Val20 of the P loop and Ile60 of switch I, which restricts access of His84 to the catalytic water
-
-
?
GTP + H2O
GDP + phosphate
Thermus thermophilus HB8 / ATCC 27634 / DSM 579
molecular recognition in the GTP-binding site, overview
-
-
?
GTP + H2O
GDP + phosphate
Thermus thermophilus HB8 / ATCC 27634 / DSM 579
-
-
GDP binding structure analysis
-
?
guanosine 5'-(thio)triphosphate + H2O
GDP + thiophosphate + 3 H+
-
-
-
?
guanosine 5'-(thio)triphosphate + H2O
GDP + thiophosphate + 3 H+
-
-
-
?
additional information
?
-
-
EF4-ribosome interactions during reverse translocation, overview
-
-
-
additional information
?
-
-
residue 196 is located in a solvent-exposed location of the G' subdomain, while its neighboring helices AG' and BG' make contacts with protein L7/L12 of the ribosome. The latter contacts involve conserved electrostatically interacting residues that allosterically activate GTP hydrolysis in the G domain of EF-G. Residue 58 moves substantially from its initial ordered position adjacent to helix BIII
-
-
-
additional information
?
-
-
EF-G binding, without GTP hydrolysis, promotes slow and possibly incomplete translocation
-
-
-
additional information
?
-
enzyme-ribosome binding analysis, overview. Binding of wild-type EF4 and mutant variants to the ribosome in the presence of guanine nucleotides, kinetics and affinities
-
-
-
additional information
?
-
-
EF4-ribosome interactions during reverse translocation, overview
-
-
-
additional information
?
-
-
GTP/GDP binding analysis using molecular dynamics and a continuum electrostatic free energy method
-
-
-
additional information
?
-
aIF2 shows very high conformational flexibility in the alpha- and beta-subunits probably required for interaction of aIF2 with the small ribosomal subunit, overview
-
-
-
additional information
?
-
-
EF-1alpha shows GTPase activity and GDP-binding ability
-
-
-
additional information
?
-
-
HflX interacts with 50S and 70S particles, and also with the 30S subunit, independent of the nucleotide-bound state and in tight binding, minimal model for the functional cycle of HflX, interaction with the 70S ribosome and functional mechanism of HflX, overview
-
-
-
additional information
?
-
-
structure-activity relationship, molecular dynamics simulations, overview
-
-
-
additional information
?
-
-
the enzyme exhibits significant binding activity with the nonformylated Met-tRNAf(Met)
-
-
-
additional information
?
-
-
eIF2A functions as a suppressor of Ure2p internal ribosome entry site-mediated translation in yeast cells
-
-
-
additional information
?
-
-
Met-tRNA + 40S ribosomal subunit {?}
-
-
?
additional information
?
-
-
Met-tRNA + 40S ribosomal subunit {?}
-
-
?
additional information
?
-
-
feeding artificial milk diets stimulate protein synthesis in skeletal muscle and liver of neonatal pigs by modulating the translation initiation factors that regulate mRNA binding to the ribosomal complex. However, provision of a high-protein diet that exceeds the protein requirement does not further enhance protein synthesis or translation initiator factor activation
-
-
-
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NATURAL SUBSTRATE
NATURAL PRODUCT
REACTION DIAGRAM
ORGANISM
UNIPROT
COMMENTARY
(Substrate)
(Substrate)
LITERATURE
(Substrate)
(Substrate)
COMMENTARY
(Product)
(Product)
LITERATURE
(Product)
(Product)
REVERSIBILITY
r=reversible
ir=irreversible
?=not specified
r=reversible
ir=irreversible
?=not specified
GTP + H2O
GDP + phosphate
-
IF2 in complex with GTP, but not GDP promotes fast association of ribosomal subunits during initiation. IF2 promotes fast formation of the first peptide bond in the presence of GTP, but not GDP. GTP form of IF2 accelerates formation of the 70S ribosome from subunits and GTP hydrolysis accelerates release of IF2 from the 70S ribosome
-
-
?
GTP + H2O
GDP + phosphate
-
importance of GTP hydrolysis in translation initiation for optimal cell growth
-
-
?
GTP + H2O
GDP + phosphate
-
release of peptide promoted by the GGQ motif of class 1 release factors regulates the GTPase activity of RF3. Binding of GTP to RF3 and GTP hydrolysis requires peptide chain release
-
-
?
GTP + H2O
GDP + phosphate
-
ribosome-dependent GTPase strongly stimulates the binding of initiator tRNA to the ribosomes even in the absence of other factors
-
-
?
GTP + H2O
GDP + phosphate
-
-
-
?
GTP + H2O
GDP + phosphate
-
elongation factor G catalyzes the translocation step in protein synthesis on the ribosome
-
-
?
guanosine 5'-(thio)triphosphate + H2O
GDP + thiophosphate + 3 H+
-
-
-
?
guanosine 5'-(thio)triphosphate + H2O
GDP + thiophosphate + 3 H+
-
-
-
?
additional information
?
-
-
EF4-ribosome interactions during reverse translocation, overview
-
-
-
additional information
?
-
-
EF-G binding, without GTP hydrolysis, promotes slow and possibly incomplete translocation
-
-
-
additional information
?
-
-
EF4-ribosome interactions during reverse translocation, overview
-
-
-
additional information
?
-
-
eIF2A functions as a suppressor of Ure2p internal ribosome entry site-mediated translation in yeast cells
-
-
-
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COFACTOR
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
additional information
-
enzyme IF2 does not have an identified nucleotide exchange factor
-
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METALS and IONS
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
CaCl2
-
10 mM, highest stimulation by BaCl2 (8fold), followed by SrCl2, MgCl2, MnCl2, CaCl2 and CoCl2 in a decreasing order of effectiveness
CoCl2
-
10 mM, highest stimulation by BaCl2 (8fold), followed by SrCl2, MgCl2, MnCl2, CaCl2 and CoCl2 in a decreasing order of effectiveness
Mg2+
MgCl2
-
10 mM, highest stimulation by BaCl2 (8fold), followed by SrCl2, MgCl2, MnCl2, CaCl2 and CoCl2 in a decreasing order of effectiveness
Mn2+
MnCl2
-
10 mM, highest stimulation by BaCl2 (8fold), followed by SrCl2, MgCl2, MnCl2, CaCl2 and CoCl2 in a decreasing order of effectiveness
Na+
SrCl2
-
10 mM, highest stimulation by BaCl2 (8fold), followed by SrCl2, MgCl2, MnCl2, CaCl2 and CoCl2 in a decreasing order of effectiveness
additional information
Mg2+
-
GTPase bound to Mg2+GDP reveals two new binding conformations. In the first the protein undergoes a conformational change that brings a conserved aspartate into its second coordination sphere. In the second, the magnesium coordination sphere is disrupted so that only five oxygen ligands are present
additional information
decreased gene expression of A1, A2, A3 and A4 gene under iron deficiency
additional information
decreased gene expression of A1, A2, A3 and A4 gene under iron deficiency
additional information
decreased gene expression of A1, A2, A3 and A4 gene under iron deficiency
additional information
decreased gene expression of A1, A2, A3 and A4 gene under iron deficiency
additional information
-
GTPase stimulated by ethylene glycol and BaCl2 does not require the presence of univalent cations. Li+, Na+, K+ or NH4+ added singularly up to 1 M concentration, do not produce any significant stimulation of SsEF-2 GTPase either in the absence or in the presence of ethylene glycol. They reduce the stimulation of SsEF-2 GTPase by ethylene glycol plus BaCl2 or SrCl2
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INHIBITOR
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
GE2270A
-
antibiotic inhibits intrinsic GTPase and that stimulated by ribosomes; thiazolyl-peptide antibiotic, inhibits both the intrinsic GTPase of elongation factor 1alpha and that stimulated by ribosomes. The M domain is the region of the enzyme most responsible for the interaction with GE2270A
guanidine hydrochloride
-
deactivation by denaturation of the protein
guanosine 5'-tetraphosphate
-
competitive inhibition of intrinsic GTPase, inhibition of archaeal protein synthesis in vitro, even though the concentration required to get inhibition is higher than that required for the eubacterial and eukaryal systems
guanosine-5'-[(beta,gamma)-imido]triphosphate
-
i.e. GppNHp. GTPase activity in the presence of a molar concentration of NaCl is competitively inhibited
tetracycline
-
mixed inhibition. The inhibition level depends on the antibiotic concentration, even though a complete inhibition is not reached even in the presence of 0.120 mM antibiotic, a concentration corresponding to about 200fold molar excess over the elongation factor
translation initiation factor IF3
-
inhibition could be overcome by increasing concentrations of divalent cations
-
Fusidic acid
-
inhibition of ribosome disassembly by EF-G and ribosome recycling factor, no influence on GTP hydrolysis
GDP
-
GTPase activity in the presence of a molar concentration of NaCl is competitively inhibited
pulvomycin
-
the antibiotic is able to reduce in vitro the rate of protein synthesis however, the concentration of pulvomycin leading to 50% inhibition (173 mM) is two order of magnitude higher but one order lower than that required in eubacteria and eukarya, respectively. Pulvomycin is able to decrease the affinity of the elongation factor toward aa-tRNA only in the presence of GTP, to an extent similar to that measured in the presence of GDP
Thiostrepton
-
inhibits the ribosome-stimulated GTPase activity of EF-G and EF4. An EF-G mutant lacking domains 4 and 5 is insensitive to the effects of thiostrepton on both GTPase activity and ribosome binding
Thiostrepton
inhibits the stimulation of the enzyme's GTPase activity by the 70S ribosome
vanadate
-
inhibition of ribosome disassembly, no influence on GTP hydrolysis
additional information
-
viomycin and fusidic acid do not prevent GTP hydrolysis, but these antibiotics trap EF-G on the ribosome before or after ribosomal translocation, respectively
-
additional information
-
in free enzyme EF-G, crucial sensors of switch I and II regions are disordered and become ordered in the complex with a nonhydrolyzable GTP analogue, GDPCP, on the ribosome. This causes a reorientation of EF-G such that the tip of domain IV moves and the CHI state ofthe ribosome is stabilized
-
additional information
subunit alpha, beta and delta of eIF2B down-regulates activity of the eIF2B catalytic subcomplex
-
additional information
-
ribosomes lacking the 23S rRNA and with deletion of SRL region, but not of GAC, inactivate EF-G1
-
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ACTIVATING COMPOUND
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
1-propanol
-
stimulation by aliphatic alcohols in a decreasing order of effectiveness: ethylene glycol > 2-propanol > ethanol > glycerol > methanol > 1-propanol
2-propanol
-
stimulation by aliphatic alcohols in a decreasing order of effectiveness: ethylene glycol > 2-propanol > ethanol > glycerol > methanol > 1-propanol
ethanol
-
stimulation by aliphatic alcohols in a decreasing order of effectiveness: ethylene glycol > 2-propanol > ethanol > glycerol > methanol > 1-propanol
glycerol
-
stimulation by aliphatic alcohols in a decreasing order of effectiveness: ethylene glycol > 2-propanol > ethanol > glycerol > methanol > 1-propanol
L7/12
-
functional compatibility between elongation factor G and the L7/12 protein in the ribosome governs its translational specificity; the C-terminal domian of L7/12 is responsible for EF-Tu function. Functional compatibility between elongation factor Tu and the L7/12 protein in the ribosome governs its translational specificity
-
methanol
-
stimulation by aliphatic alcohols in a decreasing order of effectiveness: ethylene glycol > 2-propanol > ethanol > glycerol > methanol > 1-propanol
pulvomycin
-
increasing pulvomycin concentration increased the rate of the intrinsic GTPase catalysed by elongation factor 1alpha, reaching its maximum stimulation effect at 30 mM. Pulvomycin exerts its stimulatory function at all the tested temperatures (45-75°C).
kirromycin
-
enhances activity of mutant enzyme G13A (maximal stimulation at 0.04 mM), does not stimulate intrinsic GTPase of SsEF-1alpha triggered by 3.6 M NaCl
NaCl
-
intrinsic GTPase activity of elongation factor 1alpha is triggered in vitro by NaCl at molar concentrations. The sodium ion is responsible for the induction of the GTPase activity, whereas the anion modulates the enzymatic activity through destabilization of particular regions of the protein; intrinsic GTPase activity that is triggered in vitro by NaCl at molar concentrations
ribosome
-
stimulates GTPase activity of elongation factor Tu. The factor binding site is loacetd on the 50S ribosomal subunit and comprises proteins L7/12, L10, L11, the l11-binding region of 23 rRNA, and the sarcin-ricin loop of 23S rRNA. L7/12 stimulates the GTPase activity of elongation factor G by inducing the catalytically active conformation of the G domain; stimulates GTPase activity of elongation factor Tu. The factor binding site is loacetd on the 50S ribosomal subunit and comprises proteins L7/12, L10, L11, the l11-binding region of 23 rRNA, and the sarcin-ricin loop of 23S rRNA. L7/12 stimulates the GTPase activity of elongation factor Tu by inducing the catalytically active conformation of the G domain
-
additional information
activity triggered by ribosome-induced conformational changes of EF-Tu
-
additional information
the 30S ribosome does not stimulate the enzyme
-
additional information
active in GTP-bound form, inactive in GDP-bound form; phosphorylation
-
additional information
-
GTP hydrolysis is essential for release of eIF5B from the 80S ribosomal subunit
-
additional information
active in GTP-bound form, inactive in GDP-bound form
-
additional information
active in GTP-bound form, inactive in GDP-bound form
-
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KM VALUE [mM]
SUBSTRATE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
0.00032
GTP
recombinant wild-type enzyme in presence of 70S ribosome, pH 7.5, 37°C
0.0008
GTP
-
mutant A26G, pH 7.5, 60°C, presence of 40% ethylene glycol
0.001
GTP
-
wild-type, pH 7.5, 60°C, presence of 40% ethylene glycol
0.002 - 0.009
GTP
-
depending on NaCl-concentration and temperature
0.0023
GTP
-
Ss(GM)EF-1alpha; truncated mutant, domains G+M, 60°C, pH 7.8
0.0024
GTP
-
Ss(G)EF-1alpha; truncated mutant, domain G, 60°C, pH 7.8
0.00436
GTP
-
pH 7.8, 50°C, GTPase activity in the presence 3.6 M NaCl
0.0055
GTP
-
mutant A26G, pH 7.5, 60°C, presence of 10% ethylene glycol
0.0096
GTP
-
wild-type, pH 7.5, 60°C, presence of 10% ethylene glycol
0.27
GTP
recombinant wild-type enzyme in absence of 70S ribosome, pH 7.5, 37°C
additional information
additional information
-
substrate and product binding kinetics and thermodynamics, overview
-
additional information
additional information
-
pre-steady-state kinetic analysis of HflX and Hflx ribosomal complexes interacting with GDP and a nonhydrolyzable analogue of mant-GTP, overview
-
additional information
additional information
-
ribosome binding kinetics of GTP hydrolysis-inactive recombinant EF-G mutants 58C and 196C labeled with 2',7'-difluorofluorescein maleimide, i.e. 58C-mant and 196C-mant, overview
-
additional information
additional information
-
substrate and product binding kinetics and thermodynamics with ON and OFF aIF2 , overview
-
additional information
additional information
-
substrate binding kinetics of wild-type and mutant IF2s, overview
-
additional information
additional information
-
thermodynamics of nucleotide binding
-
additional information
additional information
Michaelis-Menten kinetics of GTP hydrolysis, stopped flow measurements, kinetic analysis of wild-type and mutant enzymes, overview
-
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TURNOVER NUMBER [1/s]
SUBSTRATE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
0.003
GTP
-
pH 7.8, 50°C, GTPase activity in the presence 3.6 M NaCl
0.003
GTP
recombinant wild-type enzyme in absence of 70S ribosome, pH 7.5, 37°C
0.0033
GTP
-
wild-type, pH 7.5, 60°C, presence of 10% ethylene glycol
0.018
GTP
-
Ss(GM)EF-1alpha; truncated mutant, domains G+M, 60°C, pH 7.8
0.032
GTP
-
wild-type, pH 7.5, 60°C, presence of 40% ethylene glycol
0.12
GTP
-
mutant A26G, pH 7.5, 60°C, presence of 10% ethylene glycol
0.165
GTP
-
mutant A26G, pH 7.5, 60°C, presence of 40% ethylene glycol
2.3
GTP
recombinant wild-type enzyme in presence of 70S ribosome, pH 7.5, 37°C
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kcat/KM VALUE [1/mMs-1]
SUBSTRATE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
0.007
GTP
recombinant wild-type enzyme in presence of 70S ribosome, pH 7.5, 37°C
0.011
GTP
recombinant wild-type enzyme in absence of 70S ribosome, pH 7.5, 37°C
0.69
GTP
-
pH 7.8, 50°C, GTPase activity in the presence 3.6 M NaCl
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Ki VALUE [mM]
INHIBITOR
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
0.00047
guanosine-5'-[(beta,gamma)-imido]triphosphate
-
pH 7.8, 50°C, GTPase activity in the presence 3.6 M NaCl
0.00012
GDP
-
pH 7.8, 50°C, GTPase activity in the presence 3.6 M NaCl
0.0003
GDP
-
wild-type, pH 7.5, 60°C, presence of 40% ethylene glycol
0.0005
GDP
-
mutant A26G, pH 7.5, 60°C, presence of 40% ethylene glycol
0.0017
GDP
-
Ss(G)EF-1alpha; truncated mutant, domain G, 60°C, pH 7.8
0.0062
GDP
-
Ss(GM)EF-1alpha; truncated mutant, domains G+M, 60°C, pH 7.8
0.0193
guanosine 5'-(beta,gamma-imido)triphosphate
-
Ss(G)EF-1alpha
0.0407
guanosine 5'-(beta,gamma-imido)triphosphate
-
Ss(GM)EF-1alpha
0.0193
guanyl-5'-yl imidotriphosphate
-
truncated mutant, domain G, 60°C, pH 7.8
0.0407
guanyl-5'-yl imidotriphosphate
-
truncated mutant, domains G+M, 60°C, pH 7.8
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IC50 VALUE [mM]
INHIBITOR
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
0.0059
GE2270A
Saccharolobus solfataricus
-
half-inhibition of the GTPase of the isolated domain GM of SsEF-1alpha
0.007
GE2270A
Saccharolobus solfataricus
-
half-inhibition of the NaCl-dependent GTPase of SsEF-1alpha
0.011
GE2270A
Saccharolobus solfataricus
-
half-inhibition of the ribosome-dependent GTPase of SsEF-1alpha
0.0148
GE2270A
Saccharolobus solfataricus
-
half-inhibition of the GTPase of the isolated domain G of SsEF-1alpha
0.0463
GE2270A
Saccharolobus solfataricus
-
half-inhibition of the GTPase of a chimeric EF containing the domain G of SsEF-1alpha and the domains MC of Escherichia coli EF-Tu
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SPECIFIC ACTIVITY [µmol/min/mg]
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
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pH OPTIMUM
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
7.4
7.5
7.8
8.5
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TEMPERATURE OPTIMUM
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
25
30
37
50
60
80
87
additional information
-
the rate of nucleotide binding to aEF-1 a increased with temperature, reaching a maximum at 95°C
60
-
the GTPase activity is measured in the presence of either 3.6 M NaCl or 1.6 microM ribosomes
80
-
both Km for GTP and kcat of GTPaser increase with increasing temperature
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TEMPERATURE RANGE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
70 - 86
-
about 60% of maximal activity at 70°C and at 86°C, mutant enzyme G13A
70 - 95
-
70°C: about 60% of maximal activity, 95°C: about 90% of maximal activity, wild-type enzyme
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pI VALUE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
9.1
9.1
isoform EF-1alpha, calculated from amino acid sequence
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ORGANISM
COMMENTARY
LITERATURE
UNIPROT
SEQUENCE DB
SOURCE
Thermus thermophilus HB8 / ATCC 27634 / DSM 579
ecotype Landsberg erecta. Snowy cotyledon 1 mutant contains a mutation in a gene encoding the chloroplast elongation factor G, leading to an amino acid exchange within the predicted 70S ribosome-binding domain. The mutation results in a delay in the onset of germination. At this early developmental stage embryos still contain undifferntiated proplastids, whose proper function seems necessary for seed germination. In light-gropwn sco1 seedlings the greening of cotyledons is severely impaired, whereas the following true leaves develop normally as in wild-type plants
-
-
brenda
-
657917, 658084, 658545, 659152, 659697, 659702, 659917, 667053, 667781, 668466, 669379, 696335, 701202, 720234, 720597, 733443
-
-
brenda
; used in hybrid system with Thermus thermophilus ribosomal protein L11 - EC 3.6.5.3
-
-
brenda
and strains EF-Tu (wt) and EF-Tu (138N); elongations factor (EF)Tu
-
-
brenda
elongations factor (EF)Tu; strains MRE600, unmethylated enzyme, and LBE 1001, methylated enzyme
-
-
brenda
translation initiation factor IF2 mutants V400G and H448E, strain SL679R
-
-
brenda
-
657934, 658537, 667607, 679626, 691101, 696496, 718927, 719016, 724475, 724476, 724487, 724710, 724898, 724936, 725992
-
-
brenda
elongation factor 1alpha from strain MT3 with optimum growth temperature 75°C; elongation factor 1alpha from strain MT4 with optimum growth temperature 87°C
-
-
brenda
elongation factor 2 exhibits an intrinsic hardly detectable GTPase activity that is stimulated by ribosomes up to 2000-fold
-
-
brenda
Q97Z79: translation initiation factor 2 subunit alpha, Q97W59: translation initiation factor 2 subunit beta, Q980A5: translation initiation factor 2 subunit gamma
Q97W59; Q980A5; Q97Z79
UniProt
brenda
strain MT3, optimal growth temperature 75°C, strain MT4, optimal growth temperature 87°C
UniProt
brenda
Q97Z79: translation initiation factor 2 subunit alpha, Q97W59: translation initiation factor 2 subunit beta, Q980A5: translation initiation factor 2 subunit gamma
Q97W59; Q980A5; Q97Z79
UniProt
brenda
used in hybrid system with Escherichia coli ribosomal proteins L10, L11, L12 - EC 3.6.5.3
-
-
brenda
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SOURCE TISSUE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
SOURCE
additional information
additional information
-
growth rates of wild-type and mutant strains, overview
brenda
additional information
-
growth rates of wild-type and mutant strains, overview
-
brenda
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LOCALIZATION
ORGANISM
UNIPROT
COMMENTARY
GeneOntology No.
LITERATURE
SOURCE
-
EF-G1mt is active on both bacterial and mitochondrial ribosomes
brenda
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GENERAL INFORMATION
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
evolution
malfunction
metabolism
physiological function
additional information
evolution
-
LepA is a paralogue of elongation factor G found in all bacteria
evolution
-
unlike all other translational GTPases, the enzyme does not have an effecter domain that stably contacts the switch II region of the GTPase domain. The domain organization of enzyme IF2 is inconsistent with the articulated lever mechanism of communication between the GTPase and initiator tRNA binding domains that is proposed for the eukaryotic initiation factor 5B, eIF5B. The catalytic mechanism of enzyme IF2 appears to be unique among the translational GTPases of prokaryotes. Because the interaction of enzyme IF2 and initiator tRNA is strongest in the presence of the 30S ribosomal subunit, it is not GDP or GTP but the 30S ribosomal subunit that facilitates IF2 to interact with the initiator tRNA
evolution
-
LepA is a paralogue of elongation factor G found in all bacteria
-
evolution
Thermus thermophilus HB8 / ATCC 27634 / DSM 579
-
unlike all other translational GTPases, the enzyme does not have an effecter domain that stably contacts the switch II region of the GTPase domain. The domain organization of enzyme IF2 is inconsistent with the articulated lever mechanism of communication between the GTPase and initiator tRNA binding domains that is proposed for the eukaryotic initiation factor 5B, eIF5B. The catalytic mechanism of enzyme IF2 appears to be unique among the translational GTPases of prokaryotes. Because the interaction of enzyme IF2 and initiator tRNA is strongest in the presence of the 30S ribosomal subunit, it is not GDP or GTP but the 30S ribosomal subunit that facilitates IF2 to interact with the initiator tRNA
-
malfunction
-
an EF-G mutant lacking domains 4 and 5 shows ribosome-stimulated GTP hydrolysis activity 2.5fold slower than that of wild-type full-length EF-G and is insensitive to the effects of thiostrepton on both GTPase activity and ribosome binding
malfunction
-
in strains DEltadksA, DELTAmolR1, DELTArsgA, DELTAtatB, DELTAtonB, DELTAtolR, DELTAubiF, DELTAubiG or DELTAubiH the deletion of lepA confers a synthetic growth phenotype. The strains are compromised for gene regulation, ribosome assembly, transport and/or respiration. Loss of LepA alters the average ribosome density for hundreds of mRNA coding regions in the cell, substantially reducing average ribosome density in many cases, but only subtle and codon-specific changes in ribosome distribution along mRNA are seen. Global perturbation of gene expression in the DELTAlepA mutant likely explains most of its phenotypes. LepA variants lacking the active-site histidine or unique C-terminal domain fail to complement the synthetic phenotypes
malfunction
successive removal of the C-terminus impairs ribosome-dependent multiple turnover GTPase activity of enzyme EF4
malfunction
-
in strains DEltadksA, DELTAmolR1, DELTArsgA, DELTAtatB, DELTAtonB, DELTAtolR, DELTAubiF, DELTAubiG or DELTAubiH the deletion of lepA confers a synthetic growth phenotype. The strains are compromised for gene regulation, ribosome assembly, transport and/or respiration. Loss of LepA alters the average ribosome density for hundreds of mRNA coding regions in the cell, substantially reducing average ribosome density in many cases, but only subtle and codon-specific changes in ribosome distribution along mRNA are seen. Global perturbation of gene expression in the DELTAlepA mutant likely explains most of its phenotypes. LepA variants lacking the active-site histidine or unique C-terminal domain fail to complement the synthetic phenotypes
-
malfunction
-
an EF-G mutant lacking domains 4 and 5 shows ribosome-stimulated GTP hydrolysis activity 2.5fold slower than that of wild-type full-length EF-G and is insensitive to the effects of thiostrepton on both GTPase activity and ribosome binding
-
metabolism
-
universal mechanism for GTPase activation and hydrolysis in translational GTPases on the ribosome
metabolism
Thermus thermophilus HB8 / ATCC 27634 / DSM 579
-
universal mechanism for GTPase activation and hydrolysis in translational GTPases on the ribosome
-
physiological function
-
the universally conserved GTPase HflX is a putative translation factor whose GTPase activity is stimulated by the 70S ribosome as well as the 50S but not the 30S ribosomal subunit
physiological function
-
elongation factor G, EF-G, is one of several GTP hydrolytic proteins that cycles repeatedly on and off the ribosome during protein synthesis in bacterial cells. In the functional cycle of EF-G, hydrolysis of GTP is coupled to tRNA-mRNA translocation in ribosomes. GTP hydrolysis induces conformational rearrangements in two switch elements in the G domain of EF-G and other GTPases. These switch elements are thought to initiate the cascade of events that lead to translocation and EF-G cycling between ribosomes, coupling mechanism, overview
physiological function
-
archaeal initiation factor 2 is a protein involved in the initiation of protein biosynthesis. In its GTP-bound, ON conformation, aIF2 binds an initiator tRNA and carries it to the ribosome. In its GDP-bound, OFF conformation, it dissociates from tRNA, molecular dynamics, overview. AIF2 is largely responsible for recruiting the first, initiator tRNA to the ribosome and positioning it correctly, in register with the start codon of the ribosome-bound mRNA
physiological function
-
the EF-G GTPase mediates the movement of the tRNA2-mRNA complex during translation
physiological function
-
EF-G and EF4 perform ribosome-dependent GTP hydrolysis and bind to conserved bases in 23S rRNA and stabilize ribosomal ratcheting
physiological function
-
importance of interdomain communication in IF2, importance of GTP as an IF2 ligand in the early initiation steps and the dispensability of the free energy generated by the IF2 GTPase in the late events of the translation initiation pathway
physiological function
-
importance of interdomain communication in IF2, importance of GTP as an IF2 ligand in the early initiation steps and the dispensability of the free energy generated by the IF2 GTPase in the late events of the translation initiation pathway
physiological function
-
protein synthesis requires several GTPase factors, including elongation factor Tu, EF-Tu, which delivers aminoacyl-tRNAs to the ribosome
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
physiological function
-
synchronous tRNA movements during translocation on the ribosome are orchestrated by elongation factor G and GTP hydrolysis
physiological function
-
synchronous tRNA movements during translocation on the ribosome are orchestrated by elongation factor G and GTP hydrolysis
physiological function
-
LepA contributes mainly to the initiation phase of translation. The effect of LepA on average ribosome density is related to the sequence of the Shine-Dalgarno region. But the enzyme does not generally influence polypeptide chain elongation rate
physiological function
-
the enzyme, initiation factor 2, is a GTPase that positions the initiator tRNA on the 30S ribosomal initiation complex and stimulates its assembly to the 50S ribosomal subunit to make the 70S ribosome
physiological function
-
the GTPase aIF5B is a universally conserved initiation factor that assists ribosome assembly
physiological function
-
LepA contributes mainly to the initiation phase of translation. The effect of LepA on average ribosome density is related to the sequence of the Shine-Dalgarno region. But the enzyme does not generally influence polypeptide chain elongation rate
-
physiological function
-
EF-G and EF4 perform ribosome-dependent GTP hydrolysis and bind to conserved bases in 23S rRNA and stabilize ribosomal ratcheting
-
physiological function
Thermus thermophilus HB8 / ATCC 27634 / DSM 579
-
protein synthesis requires several GTPase factors, including elongation factor Tu, EF-Tu, which delivers aminoacyl-tRNAs to the ribosome; the enzyme, initiation factor 2, is a GTPase that positions the initiator tRNA on the 30S ribosomal initiation complex and stimulates its assembly to the 50S ribosomal subunit to make the 70S ribosome; 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
-
additional information
-
HflX-GTP exists in a structurally distinct 50S- and 70S-bound form that stabilizes GTP binding up to 70000fold and that may represent the GTPase-activated state. This activation is likely required for efficient GTP-hydrolysis, and may be similar to that observed in elongation factor G
additional information
-
cyclical movements of switch element I, sw1, within EF-G, Sw1 exposure depends on EF-G functional state, conformational changes in sw1 help to drive the unidirectional EF-G cycle during protein synthesis, intramolecular movements in EF-G, overview
additional information
-
protein:ligand interactions and conformational changes by molecular dynamics and Monte Carlo simulations, overview
additional information
-
IF2 mutant E571K, modified in its 30S binding domain IF2-G3, can perform in vitro all individual translation initiation functions of wild-type IF2 and supports faithful messenger RNA translation, despite having a reduced affinity for the 30S subunit and being completely inactive in GTP hydrolysis
additional information
-
conformational changes of enzyme IF2 upon nucleotide binding control switches I and II in the G domain, modeling, overview
additional information
-
overall scheme of translocation: in the pre-translocation state, deacylated tRNA is bound in the P site and peptidy-tRNAl in the A site, both bound to their cognate codons in the mRNA. Following the binding of EF-G-GTP to the pretranslocation complex, translocation takes place. In the post-translocation state, peptidyl-tRNA has moved to the P site, whereas deacylated tRNA has dissociated, as have inorganic phosphate and EF-G-GDP. A histidine residue in the switch II region, His91 in Escherichia coli EF-G, plays an essential role in the reaction, structure-function relationships, overview
additional information
-
overall scheme of translocation: in the pre-translocation state, deacylated tRNA is bound in the P site and peptidy-tRNAl in the A site, both bound to their cognate codons in the mRNA. Following the binding of EF-G-GTP to the pretranslocation complex, translocation takes place. In the post-translocation state, peptidyl-tRNA has moved to the P site, whereas deacylated tRNA has dissociated, as have inorganic phosphate and EF-G-GDP. A histidine residue in the switch II region, His84 in Thermus thermophilus EF-G, plays an essential role in the reaction, structure-function relationships, overview
additional information
-
histidine 81 is critical for GTPase activity, both the C-terminal domain and the GTPase activity of LepA are critical for its function in vivo
additional information
-
comparison of crystal structures of prokaryotic initiation factor 2, IF2, from Thermus thermophilus with eukaryotic initiation factor 5B, eIF5B from Methanobacterium thermoautotrophicum, structure homology modeling, overview. The structures are significantly different. Enzyme IF2 is not a classical GTPase and acts more as a conformational switch, although IF2 is not a conformational switch like EF-G and RF3 are proposed to be. Enzyme IF2 functions better with GTP but does not require it, and IF2 does not have an identified nucleotide exchange factor. Comparison of switch II regions of translational GTPases
additional information
the last 44 C-terminal amino acids of elongation factor 4 form a subdomain within the C-terminal domain that is important for GTP-dependent function on the ribosome. Efficient nucleotide hydrolysis by the enzyme on the ribosome depends on its conserved residue His 81, which is essential for catalysis in EF4
additional information
-
histidine 81 is critical for GTPase activity, both the C-terminal domain and the GTPase activity of LepA are critical for its function in vivo
-
additional information
Thermus thermophilus HB8 / ATCC 27634 / DSM 579
-
comparison of crystal structures of prokaryotic initiation factor 2, IF2, from Thermus thermophilus with eukaryotic initiation factor 5B, eIF5B from Methanobacterium thermoautotrophicum, structure homology modeling, overview. The structures are significantly different. Enzyme IF2 is not a classical GTPase and acts more as a conformational switch, although IF2 is not a conformational switch like EF-G and RF3 are proposed to be. Enzyme IF2 functions better with GTP but does not require it, and IF2 does not have an identified nucleotide exchange factor. Comparison of switch II regions of translational GTPases; conformational changes of enzyme IF2 upon nucleotide binding control switches I and II in the G domain, modeling, overview
-
Show AA Sequence and Transmembrane Helices (2710 entries)
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PDB
SCOP
CATH
UNIPROT
ORGANISM
Chaetomium thermophilum (strain DSM 1495 / CBS 144.50 / IMI 039719)
Escherichia coli (strain K12)
Halobacterium salinarum (strain ATCC 29341 / DSM 671 / R1)
Saccharomyces cerevisiae (strain ATCC 204508 / S288c)
Thermus thermophilus (strain HB8 / ATCC 27634 / DSM 579)
Chaetomium thermophilum (strain DSM 1495 / CBS 144.50 / IMI 039719)
Chaetomium thermophilum (strain DSM 1495 / CBS 144.50 / IMI 039719)
Chaetomium thermophilum (strain DSM 1495 / CBS 144.50 / IMI 039719)
Chaetomium thermophilum (strain DSM 1495 / CBS 144.50 / IMI 039719)
Chaetomium thermophilum (strain DSM 1495 / CBS 144.50 / IMI 039719)
Chaetomium thermophilum (strain DSM 1495 / CBS 144.50 / IMI 039719)
Chaetomium thermophilum (strain DSM 1495 / CBS 144.50 / IMI 039719)
Chaetomium thermophilum (strain DSM 1495 / CBS 144.50 / IMI 039719)
Chaetomium thermophilum (strain DSM 1495 / CBS 144.50 / IMI 039719)
Chaetomium thermophilum (strain DSM 1495 / CBS 144.50 / IMI 039719)