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Purine repressor
From Proteopedia
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| - | <StructureSection load=' | + | <StructureSection load='' size='450' side='right' caption='Structure of E. coli purine processor complex with DNA and guanine (PDB entry [[1wet]])' scene='55/554904/Cv/1'> |
== Function == | == Function == | ||
'''Purine repressor''' (PurR) is a member of the lac repressor family. PurP binds DNA via a highly conserved helix-turn-helix at the N terminal (DBD). PurP contains a nucleotide co-repressor binding domain as well (CBD). PurP binds to a 16-bp operator sequence and co-regulates genes which are involved in the biosynthesis of purine and pyrimidine nucleotides<ref>PMID:1971621</ref>. | '''Purine repressor''' (PurR) is a member of the lac repressor family. PurP binds DNA via a highly conserved helix-turn-helix at the N terminal (DBD). PurP contains a nucleotide co-repressor binding domain as well (CBD). PurP binds to a 16-bp operator sequence and co-regulates genes which are involved in the biosynthesis of purine and pyrimidine nucleotides<ref>PMID:1971621</ref>. | ||
== Structural highlights == | == Structural highlights == | ||
| - | The PurP guanine co-repressor binding site includes stacking interactions as well as hydrogen bonded ones. | + | The <scene name='55/554904/Cv/5'>PurP guanine co-repressor binding site includes stacking interactions as well as hydrogen bonded ones</scene>. Water molecules are shown as red spheres. The DNA binding domain contains a <scene name='55/554904/Cv/6'>helix-turn-helix-loop-helix motif which interacts with the DNA major groove</scene> and a hinge helix binding to to the DNA minor groove. <scene name='55/554904/Cv/7'>Residue L54 interdigitates with the DNA central base pair</scene><ref>PMID:9278422</ref>. |
</StructureSection> | </StructureSection> | ||
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**[[1dbq]] - EcPurR CBD + Mg - NMR<br /> | **[[1dbq]] - EcPurR CBD + Mg - NMR<br /> | ||
**[[1jhz]] - EcPurR CBD (mutant) + Mg <br /> | **[[1jhz]] - EcPurR CBD (mutant) + Mg <br /> | ||
| + | **[[1o57]] - BsPurR - ''Bacillus subtilis''<br /> | ||
*Purine repressor complex with DNA and nucleotide | *Purine repressor complex with DNA and nucleotide | ||
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**[[2puc]], [[2puf]] - EcPurR (mutant) + DNA + guanine <br /> | **[[2puc]], [[2puf]] - EcPurR (mutant) + DNA + guanine <br /> | ||
**[[1zay]] - EcPurR + DNA + hypoxanthine + di-imino-purine<br /> | **[[1zay]] - EcPurR + DNA + hypoxanthine + di-imino-purine<br /> | ||
| + | **[[7rmw]] – BsPurR + PPGPP<br /> | ||
}} | }} | ||
== References == | == References == | ||
<references/> | <references/> | ||
[[Category:Topic Page]] | [[Category:Topic Page]] | ||
Current revision
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3D structures of purine repressor
Updated on 08-February-2022
References
- ↑ Wilson HR, Turnbough CL Jr. Role of the purine repressor in the regulation of pyrimidine gene expression in Escherichia coli K-12. J Bacteriol. 1990 Jun;172(6):3208-13. PMID:1971621
- ↑ Schumacher MA, Glasfeld A, Zalkin H, Brennan RG. The X-ray structure of the PurR-guanine-purF operator complex reveals the contributions of complementary electrostatic surfaces and a water-mediated hydrogen bond to corepressor specificity and binding affinity. J Biol Chem. 1997 Sep 5;272(36):22648-53. PMID:9278422
