Mechanistic Studies of 1-Deoxy-D-Xylulose-5-Phosphate Synthase from Deinococcus radiodurans

Sumit Handa, Daniel R Dempsey, Divya Ramamoorthy, Nanci Cook, Wayne C Guida, Tyler J Spradling, Justin K White, H Lee Woodcock, David J Merkler

Biochem Mol Biol J. 2018;4(1):2.

PMID: 29552677

Abstract:

The non-mevalonate dependent (NMVA) pathway for the biosynthesis of isopentenyl pyrophosphate and dimethylallyl pyrophosphate is the sole source of these terpenoids for the production of isoprenoids in the apicomplexan parasites, in many eubacteria, and in plants. The absence of this pathway in higher organisms has opened a new platform for the development of novel antibiotics and anti-malarials. The enzyme catalyzing the first step of the NMVA pathway is 1-deoxy-D-xylulose-5-phosphate synthase (DXPS). DXPS catalyzes the thiamine pyrophosphate- and Mg (II)-dependent conjugation of pyruvate and D-glyceraldehyde-3-phosphate to form 1-deoxy-D-xylulose-5-phosphate and CO2. The kinetic mechanism of DXPS from Deinococcus radiodurans most consistent with our data is random sequential as shown using a combination of kinetic analysis and product and dead-end inhibition studies. The role of active site amino acids, identified by sequence alignment to other DXPS proteins, was probed by constructing and analyzing the catalytic efficacy of a set of targeted site-directed mutants.

Chemicals Related in the Paper:

Catalog Number	Product Name	Structure	CAS Number	Price
AP551848	D-Xylulose		551-84-8	Price
AP60299436	1-Deoxy-D-xylulose		60299-43-6	Price