View source for 3cmu


==Mechanism of homologous recombination from the RecA-ssDNA/dsDNA structures==
<StructureSection load='3cmu' size='340' side='right'caption='[[3cmu]], [[Resolution|resolution]] 4.20&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[3cmu]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. The April 2014 RCSB PDB [https://pdb.rcsb.org/pdb/static.do?p=education_discussion/molecule_of_the_month/index.html Molecule of the Month] feature on ''RecA and Rad51''  by David Goodsell is [https://dx.doi.org/10.2210/rcsb_pdb/mom_2014_4 10.2210/rcsb_pdb/mom_2014_4]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3CMU OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=3CMU FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 4.2&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=ADP:ADENOSINE-5-DIPHOSPHATE'>ADP</scene>, <scene name='pdbligand=ALF:TETRAFLUOROALUMINATE+ION'>ALF</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene></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=3cmu FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3cmu OCA], [https://pdbe.org/3cmu PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=3cmu RCSB], [https://www.ebi.ac.uk/pdbsum/3cmu PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=3cmu ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/RECA_ECOLI RECA_ECOLI] Can catalyze the hydrolysis of ATP in the presence of single-stranded DNA, the ATP-dependent uptake of single-stranded DNA by duplex DNA, and the ATP-dependent hybridization of homologous single-stranded DNAs. It interacts with LexA causing its activation and leading to its autocatalytic cleavage.[HAMAP-Rule:MF_00268]
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== Publication Abstract from PubMed ==
The RecA family of ATPases mediates homologous recombination, a reaction essential for maintaining genomic integrity and for generating genetic diversity. RecA, ATP and single-stranded DNA (ssDNA) form a helical filament that binds to double-stranded DNA (dsDNA), searches for homology, and then catalyses the exchange of the complementary strand, producing a new heteroduplex. Here we have solved the crystal structures of the Escherichia coli RecA-ssDNA and RecA-heteroduplex filaments. They show that ssDNA and ATP bind to RecA-RecA interfaces cooperatively, explaining the ATP dependency of DNA binding. The ATP gamma-phosphate is sensed across the RecA-RecA interface by two lysine residues that also stimulate ATP hydrolysis, providing a mechanism for DNA release. The DNA is underwound and stretched globally, but locally it adopts a B-DNA-like conformation that restricts the homology search to Watson-Crick-type base pairing. The complementary strand interacts primarily through base pairing, making heteroduplex formation strictly dependent on complementarity. The underwound, stretched filament conformation probably evolved to destabilize the donor duplex, freeing the complementary strand for homology sampling.

Mechanism of homologous recombination from the RecA-ssDNA/dsDNA structures.,Chen Z, Yang H, Pavletich NP Nature. 2008 May 22;453(7194):489-4. PMID:18497818<ref>PMID:18497818</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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<div class="pdbe-citations 3cmu" style="background-color:#fffaf0;"></div>

==See Also==
*[[3D structures of recombinase A|3D structures of recombinase A]]
== References ==
<references/>
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</StructureSection>
[[Category: Escherichia coli]]
[[Category: Large Structures]]
[[Category: RCSB PDB Molecule of the Month]]
[[Category: RecA and Rad51]]
[[Category: Pavletich NP]]