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| | ==DSBA MUTANT P151A, ROLE OF THE CIS-PROLINE IN THE ACTIVE SITE OF DSBA== | | ==DSBA MUTANT P151A, ROLE OF THE CIS-PROLINE IN THE ACTIVE SITE OF DSBA== |
| - | <StructureSection load='1bq7' size='340' side='right' caption='[[1bq7]], [[Resolution|resolution]] 2.80Å' scene=''> | + | <StructureSection load='1bq7' size='340' side='right'caption='[[1bq7]], [[Resolution|resolution]] 2.80Å' scene=''> |
| | == Structural highlights == | | == Structural highlights == |
| - | <table><tr><td colspan='2'>[[1bq7]] is a 6 chain structure with sequence from [http://en.wikipedia.org/wiki/"bacillus_coli"_migula_1895 "bacillus coli" migula 1895]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1BQ7 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1BQ7 FirstGlance]. <br> | + | <table><tr><td colspan='2'>[[1bq7]] is a 6 chain structure with sequence from [https://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1BQ7 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1BQ7 FirstGlance]. <br> |
| - | </td></tr><tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1bq7 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1bq7 OCA], [http://pdbe.org/1bq7 PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=1bq7 RCSB], [http://www.ebi.ac.uk/pdbsum/1bq7 PDBsum]</span></td></tr> | + | </td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 2.8Å</td></tr> |
| | + | <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=1bq7 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1bq7 OCA], [https://pdbe.org/1bq7 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1bq7 RCSB], [https://www.ebi.ac.uk/pdbsum/1bq7 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1bq7 ProSAT]</span></td></tr> |
| | </table> | | </table> |
| | == Function == | | == Function == |
| - | [[http://www.uniprot.org/uniprot/DSBA_ECOLI DSBA_ECOLI]] Required for disulfide bond formation in some periplasmic proteins such as PhoA or OmpA. Acts by transferring its disulfide bond to other proteins and is reduced in the process. DsbA is reoxidized by DsbB. Required for pilus biogenesis. PhoP-regulated transcription is redox-sensitive, being activated when the periplasm becomes more reducing (deletion of dsbA/dsbB, treatment with dithiothreitol). MgrB acts between DsbA/DsbB and PhoP/PhoQ in this pathway.<ref>PMID:1429594</ref> <ref>PMID:22267510</ref> | + | [https://www.uniprot.org/uniprot/DSBA_ECOLI DSBA_ECOLI] Required for disulfide bond formation in some periplasmic proteins such as PhoA or OmpA. Acts by transferring its disulfide bond to other proteins and is reduced in the process. DsbA is reoxidized by DsbB. Required for pilus biogenesis. PhoP-regulated transcription is redox-sensitive, being activated when the periplasm becomes more reducing (deletion of dsbA/dsbB, treatment with dithiothreitol). MgrB acts between DsbA/DsbB and PhoP/PhoQ in this pathway.<ref>PMID:1429594</ref> <ref>PMID:22267510</ref> |
| | == Evolutionary Conservation == | | == Evolutionary Conservation == |
| | [[Image:Consurf_key_small.gif|200px|right]] | | [[Image:Consurf_key_small.gif|200px|right]] |
| | Check<jmol> | | Check<jmol> |
| | <jmolCheckbox> | | <jmolCheckbox> |
| - | <scriptWhenChecked>select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/bq/1bq7_consurf.spt"</scriptWhenChecked> | + | <scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/bq/1bq7_consurf.spt"</scriptWhenChecked> |
| - | <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked> | + | <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview03.spt</scriptWhenUnchecked> |
| | <text>to colour the structure by Evolutionary Conservation</text> | | <text>to colour the structure by Evolutionary Conservation</text> |
| | </jmolCheckbox> | | </jmolCheckbox> |
| - | </jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/chain_selection.php?pdb_ID=2ata ConSurf]. | + | </jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/main_output.php?pdb_ID=1bq7 ConSurf]. |
| | <div style="clear:both"></div> | | <div style="clear:both"></div> |
| | <div style="background-color:#fffaf0;"> | | <div style="background-color:#fffaf0;"> |
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| | ==See Also== | | ==See Also== |
| - | *[[Protein disulfide oxidoreductase|Protein disulfide oxidoreductase]] | + | *[[Protein disulfide oxidoreductase 3D structures|Protein disulfide oxidoreductase 3D structures]] |
| | == References == | | == References == |
| | <references/> | | <references/> |
| | __TOC__ | | __TOC__ |
| | </StructureSection> | | </StructureSection> |
| - | [[Category: Bacillus coli migula 1895]] | + | [[Category: Escherichia coli]] |
| - | [[Category: Charbonnier, J B]] | + | [[Category: Large Structures]] |
| - | [[Category: Stura, E A]] | + | [[Category: Charbonnier J-B]] |
| - | [[Category: Disulfide oxidoreductase]] | + | [[Category: Stura EA]] |
| - | [[Category: Oxidoreductase]]
| + | |
| - | [[Category: Protein disulfide isomerase]]
| + | |
| - | [[Category: Protein folding]]
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| - | [[Category: Redox protein]]
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| - | [[Category: Redox-active center]]
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| Structural highlights
Function
DSBA_ECOLI Required for disulfide bond formation in some periplasmic proteins such as PhoA or OmpA. Acts by transferring its disulfide bond to other proteins and is reduced in the process. DsbA is reoxidized by DsbB. Required for pilus biogenesis. PhoP-regulated transcription is redox-sensitive, being activated when the periplasm becomes more reducing (deletion of dsbA/dsbB, treatment with dithiothreitol). MgrB acts between DsbA/DsbB and PhoP/PhoQ in this pathway.[1] [2]
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
In addition to the Cys-Xaa-Xaa-Cys motif at position 30-33, DsbA, the essential catalyst for disulfide bond formation in the bacterial periplasm shares with other oxidoreductases of the thioredoxin family a cis-proline in proximity of the active site residues. In the variant DsbA(P151A), this residue has been changed to an alanine, an almost isosteric residue which is not disposed to adopt the cis conformation. The substitution strongly destabilized the structure of DsbA, as determined by the decrease in the free energy of folding. The pKa of the thiol of Cys30 was only marginally decreased. Although in vivo the variant appeared to be correctly oxidized, it exhibited an activity less than half that of the wild-type enzyme with respect to the folding of alkaline phosphatase, used as a reporter of the disulfide bond formation in the periplasm. DsbA(P151A) crystallized in a different crystal form from the wild-type protein, in space group P2(1) with six molecules in the asymmetric unit. Its X-ray structure was determined to 2.8 A resolution. The most significant conformational changes occurred at the active site. The loop 149-152 adopted a new backbone conformation with Ala151 in a trans conformation. This rearrangement resulted in the loss of van der Waals interactions between this loop and the disulfide bond. His32 from the Cys-Xaa-Xaa-Cys sequence presented in four out of six molecules in the asymmetric unit a gauche conformation not observed in the wild-type protein. The X-ray structure and folding studies on DsbA(P151A) were consistent with the cis-proline playing a major role in the stabilization of the protein. A role for the positioning of the substrate is discussed. These important properties for the enzyme function might explain the conservation of this residue in DsbA and related proteins possessing the thioredoxin fold.
On the role of the cis-proline residue in the active site of DsbA.,Charbonnier JB, Belin P, Moutiez M, Stura EA, Quemeneur E Protein Sci. 1999 Jan;8(1):96-105. PMID:10210188[3]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Akiyama Y, Kamitani S, Kusukawa N, Ito K. In vitro catalysis of oxidative folding of disulfide-bonded proteins by the Escherichia coli dsbA (ppfA) gene product. J Biol Chem. 1992 Nov 5;267(31):22440-5. PMID:1429594
- ↑ Lippa AM, Goulian M. Perturbation of the oxidizing environment of the periplasm stimulates the PhoQ/PhoP system in Escherichia coli. J Bacteriol. 2012 Mar;194(6):1457-63. doi: 10.1128/JB.06055-11. Epub 2012 Jan 20. PMID:22267510 doi:http://dx.doi.org/10.1128/JB.06055-11
- ↑ Charbonnier JB, Belin P, Moutiez M, Stura EA, Quemeneur E. On the role of the cis-proline residue in the active site of DsbA. Protein Sci. 1999 Jan;8(1):96-105. PMID:10210188
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