2IXL: Rmlc S. Suis With Dtdp-Rhamnose

Citation:
Abstract
The striking feature of carbohydrates is their constitutional, conformational and configurational diversity. Biology has harnessed this diversity and manipulates carbohydrate residues in a variety of ways, one of which is epimerization. RmlC catalyzes the epimerization of the C3' and C5' positions of dTDP-6-deoxy-D-xylo-4-hexulose, forming dTDP-6-deoxy-L-lyxo-4-hexulose. RmlC is the third enzyme of the rhamnose pathway, and represents a validated anti-bacterial drug target. Although several structures of the enzyme have been reported, the mechanism and the nature of the intermediates have remained obscure. Despite its relatively small size (22 kDa), RmlC catalyzes four stereospecific proton transfers and the substrate undergoes a major conformational change during the course of the transformation. Here we report the structure of RmlC from several organisms in complex with product and product mimics. We have probed site-directed mutants by assay and by deuterium exchange. The combination of structural and biochemical data has allowed us to assign key residues and identify the conformation of the carbohydrate during turnover. Clear knowledge of the chemical structure of RmlC reaction intermediates may offer new opportunities for rational drug design.
PDB ID: 2IXLDownload
MMDB ID: 42459
PDB Deposition Date: 2006/7/8
Updated in MMDB: 2012/12
Experimental Method:
x-ray diffraction
Resolution: 1.6  Å
Source Organism:
Similar Structures:
Biological Unit for 2IXL: dimeric; determined by author and by software (PQS)
Molecular Components in 2IXL
Label Count Molecule
Proteins (2 molecules)
2
Dtdp-4-dehydrorhamnose 3,5-epimerase
Molecule annotation
Chemicals (3 molecules)
1
2
2
1
* Click molecule labels to explore molecular sequence information.

Citing MMDB
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