8amd: Difference between revisions
No edit summary |
No edit summary |
||
| Line 1: | Line 1: | ||
==Cryo-EM structure of the RecA presynaptic filament from S.pneumoniae== | |||
<StructureSection load='8amd' size='340' side='right'caption='[[8amd]], [[Resolution|resolution]] 3.90Å' scene=''> | |||
== Structural highlights == | |||
<table><tr><td colspan='2'>[[8amd]] is a 5 chain structure with sequence from [https://en.wikipedia.org/wiki/Bacteriophage_sp. Bacteriophage sp.] and [https://en.wikipedia.org/wiki/Streptococcus_pneumoniae Streptococcus pneumoniae]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=8AMD OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=8AMD FirstGlance]. <br> | |||
</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=AGS:PHOSPHOTHIOPHOSPHORIC+ACID-ADENYLATE+ESTER'>AGS</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=8amd FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=8amd OCA], [https://pdbe.org/8amd PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=8amd RCSB], [https://www.ebi.ac.uk/pdbsum/8amd PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=8amd ProSAT]</span></td></tr> | |||
</table> | |||
== Function == | |||
[https://www.uniprot.org/uniprot/A0A0B7KZM2_STREE A0A0B7KZM2_STREE] 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] | |||
<div style="background-color:#fffaf0;"> | |||
== Publication Abstract from PubMed == | |||
RecA-mediated homologous recombination (HR) is a key mechanism for genome maintenance and plasticity in bacteria. It proceeds through RecA assembly into a dynamic filament on ssDNA, the presynaptic filament, which mediates DNA homology search and ordered DNA strand exchange. Here, we combined structural, single molecule and biochemical approaches to characterize the ATP-dependent assembly mechanism of the presynaptic filament of RecA from Streptococcus pneumoniae (SpRecA), in comparison to the Escherichia coli RecA (EcRecA) paradigm. EcRecA polymerization on ssDNA is assisted by the Single-Stranded DNA Binding (SSB) protein, which unwinds ssDNA secondary structures that block EcRecA nucleofilament growth. We report by direct microscopic analysis of SpRecA filamentation on ssDNA that neither of the two paralogous pneumococcal SSBs could assist the extension of SpRecA nucleopolymers. Instead, we found that the conserved RadA helicase promotes SpRecA nucleofilamentation in an ATP-dependent manner. This allowed us to solve the atomic structure of such a long native SpRecA nucleopolymer by cryoEM stabilized with ATPgammaS. It was found to be equivalent to the crystal structure of the EcRecA filament with a marked difference in how RecA mediates nucleotide orientation in the stretched ssDNA. Then, our results show that SpRecA and EcRecA HR activities are different, in correlation with their distinct ATP-dependent ssDNA binding modes. | |||
Assembly mechanism and cryoEM structure of RecA recombination nucleofilaments from Streptococcus pneumoniae.,Hertzog M, Perry TN, Dupaigne P, Serres S, Morales V, Soulet AL, Bell JC, Margeat E, Kowalczykowski SC, Le Cam E, Fronzes R, Polard P Nucleic Acids Res. 2023 Feb 21:gkad080. doi: 10.1093/nar/gkad080. PMID:36806960<ref>PMID:36806960</ref> | |||
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |||
[[Category: | </div> | ||
[[Category: Fronzes | <div class="pdbe-citations 8amd" style="background-color:#fffaf0;"></div> | ||
[[Category: | == References == | ||
[[Category: Perry | <references/> | ||
[[Category: | __TOC__ | ||
</StructureSection> | |||
[[Category: Bacteriophage sp]] | |||
[[Category: Large Structures]] | |||
[[Category: Streptococcus pneumoniae]] | |||
[[Category: Fronzes R]] | |||
[[Category: Hertzog M]] | |||
[[Category: Perry TN]] | |||
[[Category: Polard P]] | |||
Revision as of 10:20, 22 March 2023
Cryo-EM structure of the RecA presynaptic filament from S.pneumoniaeCryo-EM structure of the RecA presynaptic filament from S.pneumoniae
Structural highlights
FunctionA0A0B7KZM2_STREE 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] Publication Abstract from PubMedRecA-mediated homologous recombination (HR) is a key mechanism for genome maintenance and plasticity in bacteria. It proceeds through RecA assembly into a dynamic filament on ssDNA, the presynaptic filament, which mediates DNA homology search and ordered DNA strand exchange. Here, we combined structural, single molecule and biochemical approaches to characterize the ATP-dependent assembly mechanism of the presynaptic filament of RecA from Streptococcus pneumoniae (SpRecA), in comparison to the Escherichia coli RecA (EcRecA) paradigm. EcRecA polymerization on ssDNA is assisted by the Single-Stranded DNA Binding (SSB) protein, which unwinds ssDNA secondary structures that block EcRecA nucleofilament growth. We report by direct microscopic analysis of SpRecA filamentation on ssDNA that neither of the two paralogous pneumococcal SSBs could assist the extension of SpRecA nucleopolymers. Instead, we found that the conserved RadA helicase promotes SpRecA nucleofilamentation in an ATP-dependent manner. This allowed us to solve the atomic structure of such a long native SpRecA nucleopolymer by cryoEM stabilized with ATPgammaS. It was found to be equivalent to the crystal structure of the EcRecA filament with a marked difference in how RecA mediates nucleotide orientation in the stretched ssDNA. Then, our results show that SpRecA and EcRecA HR activities are different, in correlation with their distinct ATP-dependent ssDNA binding modes. Assembly mechanism and cryoEM structure of RecA recombination nucleofilaments from Streptococcus pneumoniae.,Hertzog M, Perry TN, Dupaigne P, Serres S, Morales V, Soulet AL, Bell JC, Margeat E, Kowalczykowski SC, Le Cam E, Fronzes R, Polard P Nucleic Acids Res. 2023 Feb 21:gkad080. doi: 10.1093/nar/gkad080. PMID:36806960[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
|
| ||||||||||||||||