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2adn

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Solution structure of the bacterial antitoxin CcdA: Implications for DNA and toxin binding

Structural highlights

2adn is a 2 chain structure with sequence from Escherichia coli. Full experimental information is available from OCA. For a guided tour on the structure components use FirstGlance.
Method:	Solution NMR
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

CCDA_ECOLI Antitoxin component of a toxin-antitoxin (TA) module which inhibits the post-segregational killing (PSK) of plasmid-free cells, also referred to as a plasmid addiction system. Labile antitoxin with a half-life of about 1 hour in the presence of CcdB. Binds to and blocks the activity of CcdB; will also remove bound CcdB protein from the CcdB-GyrA complex by forming a CcdA-CcdB complex, a process termed rejuvenation. The N-terminal 36 residues are not required for rejuventation. Functions as a transcriptional corepressor for the ccdAB operon, repression also requires CcdB.^[1] ^[2] ^[3] ^[4] ^[5] ^[6] ^[7]

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

Toxin-antitoxin systems are highly abundant in plasmids and bacterial chromosomes. They ensure plasmid maintenance by killing bacteria that have lost the plasmid. Their expression is autoregulated at the level of transcription. Here, we present the solution structure of CcdA, the antitoxin of the ccd system, as a free protein (16.7 kDa) and in complex with its cognate DNA (25.3 kDa). CcdA is composed of two distinct and independent domains: the N-terminal domain, responsible for DNA binding, which establishes a new family of the ribbon-helix-helix fold and the C-terminal region, which is responsible for the interaction with the toxin CcdB. The C-terminal domain is intrinsically unstructured and forms a tight complex with the toxin. We show that CcdA specifically recognizes a 6 bp palindromic DNA sequence within the operator-promoter (OP) region of the ccd operon and binds to DNA by insertion of the positively charged N-terminal beta-sheet into the major groove. The binding of up to three CcdA dimers to a 33mer DNA of its operator-promoter region was studied by NMR spectroscopy, isothermal titration calorimetry and single point mutation. The highly flexible C-terminal region of free CcdA explains its susceptibility to proteolysis by the Lon ATP-dependent protease.

Structural basis for nucleic acid and toxin recognition of the bacterial antitoxin CcdA.,Madl T, Van Melderen L, Mine N, Respondek M, Oberer M, Keller W, Khatai L, Zangger K J Mol Biol. 2006 Nov 24;364(2):170-85. Epub 2006 Sep 1. PMID:17007877^[8]

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

References

↑ Miki T, Yoshioka K, Horiuchi T. Control of cell division by sex factor F in Escherichia coli. I. The 42.84-43.6 F segment couples cell division of the host bacteria with replication of plasmid DNA. J Mol Biol. 1984 Apr 25;174(4):605-25. PMID:6327993
↑ Tam JE, Kline BC. Control of the ccd operon in plasmid F. J Bacteriol. 1989 May;171(5):2353-60. PMID:2651399
↑ Ogura T, Hiraga S. Mini-F plasmid genes that couple host cell division to plasmid proliferation. Proc Natl Acad Sci U S A. 1983 Aug;80(15):4784-8. PMID:6308648
↑ Tam JE, Kline BC. The F plasmid ccd autorepressor is a complex of CcdA and CcdB proteins. Mol Gen Genet. 1989 Oct;219(1-2):26-32. PMID:2615761
↑ Bernard P, Couturier M. Cell killing by the F plasmid CcdB protein involves poisoning of DNA-topoisomerase II complexes. J Mol Biol. 1992 Aug 5;226(3):735-45. PMID:1324324
↑ Maki S, Takiguchi S, Horiuchi T, Sekimizu K, Miki T. Partner switching mechanisms in inactivation and rejuvenation of Escherichia coli DNA gyrase by F plasmid proteins LetD (CcdB) and LetA (CcdA). J Mol Biol. 1996 Mar 1;256(3):473-82. PMID:8604132 doi:http://dx.doi.org/10.1006/jmbi.1996.0102
↑ De Jonge N, Garcia-Pino A, Buts L, Haesaerts S, Charlier D, Zangger K, Wyns L, De Greve H, Loris R. Rejuvenation of CcdB-poisoned gyrase by an intrinsically disordered protein domain. Mol Cell. 2009 Jul 31;35(2):154-63. PMID:19647513 doi:10.1016/j.molcel.2009.05.025
↑ Madl T, Van Melderen L, Mine N, Respondek M, Oberer M, Keller W, Khatai L, Zangger K. Structural basis for nucleic acid and toxin recognition of the bacterial antitoxin CcdA. J Mol Biol. 2006 Nov 24;364(2):170-85. Epub 2006 Sep 1. PMID:17007877 doi:10.1016/j.jmb.2006.08.082

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

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/2adn"

@@ Line 1: / Line 1: @@
 ==Solution structure of the bacterial antitoxin CcdA: Implications for DNA and toxin binding==
-<StructureSection load='2adn' size='340' side='right'caption='[[2adn]], [[NMR_Ensembles_of_Models | 1 NMR models]]' scene=''>
+<StructureSection load='2adn' size='340' side='right'caption='[[2adn]]' scene=''>
 == Structural highlights ==
-<table><tr><td colspan='2'>[[2adn]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/"bacillus_coli"_migula_1895 "bacillus coli" migula 1895]. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2ADN OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2ADN FirstGlance]. <br>
+<table><tr><td colspan='2'>[[2adn]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2ADN OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2ADN FirstGlance]. <br>
-</td></tr><tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat"><div style='overflow: auto; max-height: 3em;'>[[2adl|2adl]]</div></td></tr>
+</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">Solution NMR</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=2adn FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2adn OCA], [https://pdbe.org/2adn PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2adn RCSB], [https://www.ebi.ac.uk/pdbsum/2adn PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2adn ProSAT]</span></td></tr>
 </table>
+== Function ==
+[https://www.uniprot.org/uniprot/CCDA_ECOLI CCDA_ECOLI] Antitoxin component of a toxin-antitoxin (TA) module which inhibits the post-segregational killing (PSK) of plasmid-free cells, also referred to as a plasmid addiction system. Labile antitoxin with a half-life of about 1 hour in the presence of CcdB. Binds to and blocks the activity of CcdB; will also remove bound CcdB protein from the CcdB-GyrA complex by forming a CcdA-CcdB complex, a process termed rejuvenation. The N-terminal 36 residues are not required for rejuventation. Functions as a transcriptional corepressor for the ccdAB operon, repression also requires CcdB.<ref>PMID:6327993</ref> <ref>PMID:2651399</ref> <ref>PMID:6308648</ref> <ref>PMID:2615761</ref> <ref>PMID:1324324</ref> <ref>PMID:8604132</ref> <ref>PMID:19647513</ref>
 == Evolutionary Conservation ==
 [[Image:Consurf_key_small.gif|200px|right]]
@@ Line 30: / Line 32: @@
 __TOC__
 </StructureSection>
-[[Category: Bacillus coli migula 1895]]
+[[Category: Escherichia coli]]
 [[Category: Large Structures]]
-[[Category: Keller, W]]
+[[Category: Keller W]]
-[[Category: Khatai, L]]
+[[Category: Khatai L]]
-[[Category: Madl, T]]
+[[Category: Madl T]]
-[[Category: Oberer, M]]
+[[Category: Oberer M]]
-[[Category: VanMelderen, L]]
+[[Category: VanMelderen L]]
-[[Category: Zangger, K]]
+[[Category: Zangger K]]
-[[Category: Dna binding protein]]
-[[Category: Ribbon-helix-helix]]

2adn

From Proteopedia

Current revision

Solution structure of the bacterial antitoxin CcdA: Implications for DNA and toxin binding

Structural highlights

Function

Evolutionary Conservation

Publication Abstract from PubMed

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

Views

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