Protocol abstract
Nature Protocols 2, - 1825 - 1830 (2007)
Published online: 19 July 2007 | doi:10.1038/nprot.2007.260
Subject Categories: Synthetic chemistry | Biochemistry and protein analysis
Pyruvate aldolases in chiral carbon–carbon bond formation
Matthew J Walters1,2 & Eric J Toone1,2
Abstract
A procedure for the preparation of optically pure 
-keto-
-hydroxy carboxylic acids through stereospecific aldol addition catalyzed by pyruvate aldolases from the Entner–Doudoroff and the DeLey–Doudoroff glycolytic pathways is described. This highly versatile fragment serves as a precursor for a variety of commonly encountered functionalities, including 
-hydroxy aldehydes and carboxylic acids, -amino--hydroxy carboxylic acids and ,-dihydroxy carboxylic acids. The protocol described here uses recombinant His6-tagged KDPG aldolase for the synthesis of (S)-4-hydroxy-2-keto-4-(2'-pyridyl)butyrate. A protocol for evaluating enantiomeric excess through formation of the -lactone of the dithioacetal followed by chiral-phase gas–liquid chromatography is also described. Enzyme expression and enzymatic synthesis can be accomplished in approximately 1 week. The enzymatic aldol addition proceeds in nearly quantitative yields with enantiomeric excesses greater than 99.7%.
- Department of Chemistry, Duke University, Durham, North Carolina 27708, USA.
- Department of Biochemistry, Duke University Medical Center, Durham, North Carolina 27710, USA.
Correspondence to: Eric J Toone1,2 e-mail: eric.toone@duke.edu
nature-products
A-Z product listing
- (TLC) plate(EMD Chemicals Inc.)
- 12% (w/v) Tris-HCl gel(Bio-Rad)
- 150 ml lyophilizer jar(Labcono)
- 2-pyridinecarboxaldehyde(Aldrich)
- 250 ml Erlenmeyer flask(Corning)
- 250 ml filter system(Corning)