2oen: Difference between revisions

Revision as of 06:48, 28 July 2008

This article has been automatically seeded. Changes to this page should pertain to the PDB entry only and not to the protein or biomolecule in general.

File:2oen.png

Template:STRUCTURE 2oen

Structural mechanism for the fine-tuning of CcpA function by the small molecule effectors glucose-6-phosphate and fructose-1,6-bisphosphateStructural mechanism for the fine-tuning of CcpA function by the small molecule effectors glucose-6-phosphate and fructose-1,6-bisphosphate

Template:ABSTRACT PUBMED 17376479

About this StructureAbout this Structure

2OEN is a Protein complex structure of sequences from Bacillus megaterium. Full crystallographic information is available from OCA.

ReferenceReference

Structural mechanism for the fine-tuning of CcpA function by the small molecule effectors glucose 6-phosphate and fructose 1,6-bisphosphate., Schumacher MA, Seidel G, Hillen W, Brennan RG, J Mol Biol. 2007 May 11;368(4):1042-50. Epub 2007 Feb 27. PMID:17376479

Page seeded by OCA on Mon Jul 28 06:48:57 2008

Proteopedia Page Contributors and Editors (what is this?)Proteopedia Page Contributors and Editors (what is this?)

OCA

@@ Line 1: / Line 1: @@
-[[Image:2oen.jpg|left|200px]]
+{{Seed}}
+[[Image:2oen.png|left|200px]]
 <!--
@@ Line 9: / Line 10: @@
 {{STRUCTURE_2oen|  PDB=2oen  |  SCENE=  }}
-'''Structural mechanism for the fine-tuning of CcpA function by the small molecule effectors glucose-6-phosphate and fructose-1,6-bisphosphate'''
+===Structural mechanism for the fine-tuning of CcpA function by the small molecule effectors glucose-6-phosphate and fructose-1,6-bisphosphate===
-==Overview==
+<!--
-In Gram-positive bacteria, carbon catabolite regulation (CCR) is mediated by the carbon catabolite control protein A (CcpA), a member of the LacI-GalR family of transcription regulators. Unlike other LacI-GalR proteins, CcpA is activated to bind DNA by binding the phosphoproteins HPr-Ser46-P or Crh-Ser46-P. However, fine regulation of CCR is accomplished by the small molecule effectors, glucose 6-phosphate (G6P) and fructose 1,6-bisphosphate (FBP), which somehow enhance CcpA-(HPr-Ser46-P) binding to DNA. Unlike the CcpA-(HPr-Ser46-P) complex, DNA binding by CcpA-(Crh-Ser46-P) is not stimulated by G6P or FBP. To understand the fine-tuning mechanism of these effectors, we solved the structures of the CcpA core, DeltaCcpA, which lacks the N-terminal DNA-binding domain, in complex with HPr-Ser46-P and G6P or FBP. G6P and FBP bind in a deep cleft, between the N and C subdomains of CcpA. Neither interacts with HPr-Ser46-P. This suggests that one role of the adjunct corepressors is to buttress the DNA-binding conformation effected by the binding of HPr-Ser46-P to the CcpA dimer N subdomains. However, the structures reveal that an unexpected function of adjunct corepressor binding is to bolster cross interactions between HPr-Ser46-P residue Arg17 and residues Asp69 and Asp99 of the other CcpA subunit. These cross contacts, which are weak or not present in the CcpA-(Crh-Ser46-P) complex, stimulate the CcpA-(HPr-Ser46-P)-DNA interaction specifically. Thus, stabilization of the closed conformation and bolstering of cross contacts between CcpA and its other corepressor, HPr-Ser46-P, provide a molecular explanation for how adjunct corepressors G6P and FBP enhance the interaction between CcpA-(HPr-Ser46-P) and cognate DNA.
+The line below this paragraph, {{ABSTRACT_PUBMED_17376479}}, adds the Publication Abstract to the page
+(as it appears on PubMed at http://www.pubmed.gov), where 17376479 is the PubMed ID number.
+-->
+{{ABSTRACT_PUBMED_17376479}}
 ==About this Structure==
@@ Line 32: / Line 36: @@
 [[Category: Hpr]]
 [[Category: Protein-dna]]
-''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun May  4 10:44:57 2008''
+''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Mon Jul 28 06:48:57 2008''