3L2I image
Entry Detail
PDB ID:
3L2I
Keywords:
Title:
1.85 Angstrom Crystal Structure of the 3-Dehydroquinate Dehydratase (aroD) from Salmonella typhimurium LT2.
Biological Source:
PDB Version:
Deposition Date:
2009-12-15
Release Date:
2009-12-29
Method Details:
Experimental Method:
Resolution:
1.85 Å
R-Value Free:
0.21
R-Value Work:
0.16
R-Value Observed:
0.16
Space Group:
P 21 21 21
Macromolecular Entities
Polymer Type:polypeptide(L)
Description:3-dehydroquinate dehydratase
Chain IDs:A, B
Chain Length:276
Number of Molecules:2
Biological Source:Salmonella enterica subsp. enterica serovar Typhimurium
Ligand Molecules
Primary Citation
A conserved surface loop in type I dehydroquinate dehydratases positions an active site arginine and functions in substrate binding.
Biochemistry 50 2357 2363 (2011)
PMID: 21291284 DOI: 10.1021/bi102020s

Abstact

Dehydroquinate dehydratase (DHQD) catalyzes the third step in the biosynthetic shikimate pathway. We present three crystal structures of the Salmonella enterica type I DHQD that address the functionality of a surface loop that is observed to close over the active site following substrate binding. Two wild-type structures with differing loop conformations and kinetic and structural studies of a mutant provide evidence of both direct and indirect mechanisms of involvement of the loop in substrate binding. In addition to allowing amino acid side chains to establish a direct interaction with the substrate, closure of the loop necessitates a conformational change of a key active site arginine, which in turn positions the substrate productively. The absence of DHQD in humans and its essentiality in many pathogenic bacteria make the enzyme a target for the development of nontoxic antimicrobials. The structures and ligand binding insights presented here may inform the design of novel type I DHQD inhibiting molecules.

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Primary Citation of related structures