 The degradation of serine to pyruvate is an example of a pyridoxal phosphate-dependent (PLP) catalyzed Beta-elimination reaction.Beta-eliminations mediated by PLP yields products that have undergone a two-electron oxidation at C-alpha.In general, beta-eliminations involve the removal of a halide and a proton from the adjacent beta-carbon to give a double bond; thus, the origin of the double bond pi electrons are from the C-H bond on the beta carbon of the substrate.