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1ega

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Revision as of 06:58, 12 June 2019

CRYSTAL STRUCTURE OF A WIDELY CONSERVED GTPASE ERA

Structural highlights

1ega is a 2 chain structure with sequence from Escherichia coli. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Ligands:
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

[ERA_ECOLI] An essential GTPase that binds both GDP and GTP, with nucleotide exchange occurring on the order of seconds whereas hydrolysis occurs on the order of minutes. Plays a role in numerous processes, including cell cycle regulation, energy metabolism, as a chaperone for 16S rRNA processing and 30S ribosomal subunit biogenesis. Its presence in the 30S subunit may prevent translation initiation. Seems to be critical for maintaining cell growth and cell divison rates; a dramatic reduction in Era protein levels temporarily arrests cell growth just before cytokinesis (at the predivisional two-cell stage) and delays cell division. Era mutant era1 suppresses some temperature-sensitive mutations that affect DNA replication and chromosome partitioning and segregation. The dominant-negative Era-de mutant which is missing residues in a putative effector region, is unable to complement the disruption mutant; upon overproduction it shows a significant decrease in cell viability and a synthetic lethal phenotype in the presence of acetate. Era function probably overlaps RbfA. Binds to the pre-30S subunit through several stages of protein assembly.^[1] ^[2] ^[3] ^[4] ^[5]

Evolutionary Conservation

Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.

Publication Abstract from PubMed

ERA forms a unique family of GTPase. It is widely conserved and essential in bacteria. ERA functions in cell cycle control by coupling cell division with growth rate. ERA homologues also are found in eukaryotes. Here we report the crystal structure of ERA from Escherichia coli. The structure has been determined at 2.4-A resolution. It reveals a two-domain arrangement of the molecule: an N-terminal domain that resembles p21 Ras and a C-terminal domain that is unique. Structure-based topological search of the C domain fails to reveal any meaningful match, although sequence analysis suggests that it contains a KH domain. KH domains are RNA binding motifs that usually occur in tandem repeats and exhibit low sequence similarity except for the well-conserved segment VIGxxGxxIK. We have identified a betaalphaalphabeta fold that contains the VIGxxGxxIK sequence and is shared by the C domain of ERA and the KH domain. We propose that this betaalphaalphabeta fold is the RNA binding motif, the minimum structural requirement for RNA binding. ERA dimerizes in crystal. The dimer formation involves a significantly distorted switch II region, which may shed light on how ERA protein regulates downstream events.

Crystal structure of ERA: a GTPase-dependent cell cycle regulator containing an RNA binding motif.,Chen X, Court DL, Ji X Proc Natl Acad Sci U S A. 1999 Jul 20;96(15):8396-401. PMID:10411886^[6]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Britton RA, Powell BS, Dasgupta S, Sun Q, Margolin W, Lupski JR, Court DL. Cell cycle arrest in Era GTPase mutants: a potential growth rate-regulated checkpoint in Escherichia coli. Mol Microbiol. 1998 Feb;27(4):739-50. PMID:9515700
↑ Inoue K, Chen J, Kato I, Inouye M. Specific growth inhibition by acetate of an Escherichia coli strain expressing Era-dE, a dominant negative Era mutant. J Mol Microbiol Biotechnol. 2002 Jul;4(4):379-88. PMID:12125819
↑ Inoue K, Alsina J, Chen J, Inouye M. Suppression of defective ribosome assembly in a rbfA deletion mutant by overexpression of Era, an essential GTPase in Escherichia coli. Mol Microbiol. 2003 May;48(4):1005-16. PMID:12753192
↑ Inoue K, Chen J, Tan Q, Inouye M. Era and RbfA have overlapping function in ribosome biogenesis in Escherichia coli. J Mol Microbiol Biotechnol. 2006;11(1-2):41-52. PMID:16825789 doi:10.1159/000092818
↑ Bunner AE, Nord S, Wikstrom PM, Williamson JR. The effect of ribosome assembly cofactors on in vitro 30S subunit reconstitution. J Mol Biol. 2010 Apr 23;398(1):1-7. doi: 10.1016/j.jmb.2010.02.036. Epub 2010 Feb, 24. PMID:20188109 doi:10.1016/j.jmb.2010.02.036
↑ Chen X, Court DL, Ji X. Crystal structure of ERA: a GTPase-dependent cell cycle regulator containing an RNA binding motif. Proc Natl Acad Sci U S A. 1999 Jul 20;96(15):8396-401. PMID:10411886

1 Structural highlights
2 Function
3 Evolutionary Conservation
4 Publication Abstract from PubMed
5 See Also
6 References

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/1ega"

@@ Line 1: / Line 1: @@
 ==CRYSTAL STRUCTURE OF A WIDELY CONSERVED GTPASE ERA==
-<StructureSection load='1ega' size='340' side='right' caption='[[1ega]], [[Resolution|resolution]] 2.40&Aring;' scene=''>
+<StructureSection load='1ega' size='340' side='right'caption='[[1ega]], [[Resolution|resolution]] 2.40&Aring;' scene=''>
 == Structural highlights ==
 <table><tr><td colspan='2'>[[1ega]] is a 2 chain structure with sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1EGA OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1EGA FirstGlance]. <br>
@@ Line 13: / Line 13: @@
 Check<jmol>
   <jmolCheckbox>
-    <scriptWhenChecked>select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/eg/1ega_consurf.spt"</scriptWhenChecked>
+    <scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/eg/1ega_consurf.spt"</scriptWhenChecked>
     <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked>
     <text>to colour the structure by Evolutionary Conservation</text>
@@ Line 36: / Line 36: @@
 </StructureSection>
 [[Category: Escherichia coli]]
+[[Category: Large Structures]]
 [[Category: Chen, X]]
 [[Category: Ji, X]]

1ega

From Proteopedia

Revision as of 06:58, 12 June 2019

CRYSTAL STRUCTURE OF A WIDELY CONSERVED GTPASE ERA

Structural highlights

Function

Evolutionary Conservation

Publication Abstract from PubMed

See Also

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

Views

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