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Updated: Sep 27, 2026

Light-driven Enzymatic Decarboxylation
Published on: May 22, 2016
Stereochemical studies on phosphopantothenoylcysteine decarboxylase from Escherichia coli
Erick Strauss1, Tadhg P Begley
1Department of Chemistry and Chemical Biology, Cornell University, Baker Laboratory, Ithaca, NY 14853, USA.
Abstract:
Phosphopantothenoylcysteine decarboxylase catalyzes the decarboxylation of 4'-phosphopantothenoylcysteine (2) to form 4'-phosphopanthetheine (3), an intermediate in the biosynthesis of Coenzyme A. In this study we investigated the stereochemistry of this reaction. Our results show that the decarboxylation proceeds with retention of stereochemistry, and that the pro-R proton at C(beta) of the cysteine moiety of 2 is removed during a reversible oxidation of the thiol to a thioaldehyde intermediate.
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