The Position of a Key Tyrosine in Dtdp-4-Keto-6-Deoxy-D-Glucose-5-Epimerase (Evad) Alters the Substrate Profile for This Rmlc-Like EnzymeMerkel, A.B., Major, L.L., Errey, J.C., Burkart, M.D., Field, R.A., Walsh, C.T., Naismith, J.H.
(2004) J Biol Chem 279: 32684
- PubMed: 15159413
- DOI: 10.1074/jbc.M404091200
- Primary Citation of Related Structures:
- PubMed Abstract:
- Purification, Crystallisation and Preliminary Structural Studies of Dtdp-4-Keto-6-Deoxy-Glucose-5-Epimerase (Evad) from Amycolatpsis Orientalis; the Fourth Enzyme in the Dtdp-L-Epivancosamine Pathway
Merkel, A.B., Temple, G.K., Burkhart, M., Beis, K., Walsh, C.T., Naismith, J.H.
(2002) Acta Crystallogr D Biol Crystallogr 58: 1226
Vancomycin, the last line of defense antibiotic, depends upon the attachment of the carbohydrate vancosamine to an aglycone skeleton for antibacterial activity. Vancomycin is a naturally occurring secondary metabolite that can be produced by bacteria ...
Vancomycin, the last line of defense antibiotic, depends upon the attachment of the carbohydrate vancosamine to an aglycone skeleton for antibacterial activity. Vancomycin is a naturally occurring secondary metabolite that can be produced by bacterial fermentation. To combat emerging resistance, it has been proposed to genetically engineer bacteria to produce analogues of vancomycin. This requires a detailed understanding of the biochemical steps in the synthesis of vancomycin. Here we report the 1.4 A structure and biochemical characterization of EvaD, an RmlC-like protein that is required for the C-5' epimerization during synthesis of dTDP-epivancosamine. EvaD, although clearly belonging to the RmlC class of enzymes, displays very low activity in the archetypal RmlC reaction (double epimerization of dTDP-6-deoxy-4-keto-D-glucose at C-3' and C-5'). The high resolution structure of EvaD compared with the structures of authentic RmlC enzymes indicates that a subtle change in the enzyme active site repositions a key catalytic Tyr residue. A mutant designed to re-establish the normal position of the Tyr increases the RmlC-like activity of EvaD.
Centre for Biomolecular Sciences, The University, St. Andrews, Scotland, KY16 9ST, United Kingdom.