8tk0: Difference between revisions
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The | ==Structure of Gabija AB complex== | ||
<StructureSection load='8tk0' size='340' side='right'caption='[[8tk0]], [[Resolution|resolution]] 3.23Å' scene=''> | |||
== Structural highlights == | |||
<table><tr><td colspan='2'>[[8tk0]] is a 4 chain structure with sequence from [https://en.wikipedia.org/wiki/Bacillus_cereus Bacillus cereus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=8TK0 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=8TK0 FirstGlance]. <br> | |||
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">Electron Microscopy, [[Resolution|Resolution]] 3.23Å</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=8tk0 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=8tk0 OCA], [https://pdbe.org/8tk0 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=8tk0 RCSB], [https://www.ebi.ac.uk/pdbsum/8tk0 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=8tk0 ProSAT]</span></td></tr> | |||
</table> | |||
== Function == | |||
[https://www.uniprot.org/uniprot/GAJA_BACC6 GAJA_BACC6] Component of antiviral defense system Gabija type I, composed of GajA and GajB (PubMed:29371424). Endonuclease that nicks double-stranded DNA within the sequence 5'-TNNNCGGGNNA-3' in the absence of nucleotides (NTP, dNTP and NDPs), cleaving after C-1 (PubMed:33885789, PubMed:37992757). Has no detected ATPase activity (PubMed:33885789). Expression of Gabija type I in B.subtilis (strain BEST7003) confers resistance to phages phi105, phi29, rho14, SpBeta and SBSphiC (PubMed:29371424). Expression of Gabija type I in E.coli B (strain ATCC 11303) confers resistance to phage T7 (PubMed:33885789). It is thought that this enzyme is strongly suppressed during physiological growth (in E.coli total nucleotide concentration is over 8.7 mM in mid-log phase), but during viral replication, when nucleotides are rapidly consumed, it is de-suppressed and degrades target DNA (Probable).<ref>PMID:29371424</ref> <ref>PMID:33885789</ref> <ref>PMID:37992757</ref> <ref>PMID:33885789</ref> | |||
<div style="background-color:#fffaf0;"> | |||
== Publication Abstract from PubMed == | |||
As one of the most prevalent anti-phage defense systems in prokaryotes, Gabija consists of a Gabija protein A (GajA) and a Gabija protein B (GajB). The assembly and function of the Gabija system remain unclear. Here we present cryo-EM structures of Bacillus cereus GajA and GajAB complex, revealing tetrameric and octameric assemblies, respectively. In the center of the complex, GajA assembles into a tetramer, which recruits two sets of GajB dimer at opposite sides of the complex, resulting in a 4:4 GajAB supramolecular complex for anti-phage defense. Further biochemical analysis showed that GajA alone is sufficient to cut double-stranded DNA and plasmid DNA, which can be inhibited by ATP. Unexpectedly, the GajAB displays enhanced activity for plasmid DNA, suggesting a role of substrate selection by GajB. Together, our study defines a framework for understanding anti-phage immune defense by the GajAB complex. | |||
Molecular basis of Gabija anti-phage supramolecular assemblies.,Yang XY, Shen Z, Xie J, Greenwald J, Marathe I, Lin Q, Xie WJ, Wysocki VH, Fu TM Nat Struct Mol Biol. 2024 Aug;31(8):1243-1250. doi: 10.1038/s41594-024-01283-w. , Epub 2024 Apr 16. PMID:38627580<ref>PMID:38627580</ref> | |||
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |||
[[Category: | </div> | ||
<div class="pdbe-citations 8tk0" style="background-color:#fffaf0;"></div> | |||
== References == | |||
<references/> | |||
__TOC__ | |||
</StructureSection> | |||
[[Category: Bacillus cereus]] | |||
[[Category: Large Structures]] | |||
[[Category: Fu TM]] | |||
[[Category: Shen ZF]] | |||
[[Category: Yang XY]] |
Latest revision as of 08:29, 28 August 2024
Structure of Gabija AB complexStructure of Gabija AB complex
Structural highlights
FunctionGAJA_BACC6 Component of antiviral defense system Gabija type I, composed of GajA and GajB (PubMed:29371424). Endonuclease that nicks double-stranded DNA within the sequence 5'-TNNNCGGGNNA-3' in the absence of nucleotides (NTP, dNTP and NDPs), cleaving after C-1 (PubMed:33885789, PubMed:37992757). Has no detected ATPase activity (PubMed:33885789). Expression of Gabija type I in B.subtilis (strain BEST7003) confers resistance to phages phi105, phi29, rho14, SpBeta and SBSphiC (PubMed:29371424). Expression of Gabija type I in E.coli B (strain ATCC 11303) confers resistance to phage T7 (PubMed:33885789). It is thought that this enzyme is strongly suppressed during physiological growth (in E.coli total nucleotide concentration is over 8.7 mM in mid-log phase), but during viral replication, when nucleotides are rapidly consumed, it is de-suppressed and degrades target DNA (Probable).[1] [2] [3] [4] Publication Abstract from PubMedAs one of the most prevalent anti-phage defense systems in prokaryotes, Gabija consists of a Gabija protein A (GajA) and a Gabija protein B (GajB). The assembly and function of the Gabija system remain unclear. Here we present cryo-EM structures of Bacillus cereus GajA and GajAB complex, revealing tetrameric and octameric assemblies, respectively. In the center of the complex, GajA assembles into a tetramer, which recruits two sets of GajB dimer at opposite sides of the complex, resulting in a 4:4 GajAB supramolecular complex for anti-phage defense. Further biochemical analysis showed that GajA alone is sufficient to cut double-stranded DNA and plasmid DNA, which can be inhibited by ATP. Unexpectedly, the GajAB displays enhanced activity for plasmid DNA, suggesting a role of substrate selection by GajB. Together, our study defines a framework for understanding anti-phage immune defense by the GajAB complex. Molecular basis of Gabija anti-phage supramolecular assemblies.,Yang XY, Shen Z, Xie J, Greenwald J, Marathe I, Lin Q, Xie WJ, Wysocki VH, Fu TM Nat Struct Mol Biol. 2024 Aug;31(8):1243-1250. doi: 10.1038/s41594-024-01283-w. , Epub 2024 Apr 16. PMID:38627580[5] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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