Glyceraldehyde-3-phosphate is both expensive and relatively unstable, degrading to methyl glyoxal and free phosphate at neutral pH . One way to offset these problems is to generate D-or L-glyceraldehyde-3-phosphate from D-or L-glyceraldehyde respectively in situ using a kinase, an approach that has been employed previously when using FSA aldolase . L-G3P (1a) can be generated from L-glyeraldehyde (15) using glycerokinase from Cellumonas. sp 27 (scheme 1A) and D-G3P (1b) can be generated from Dglyceraldehyde ( ) using dihydroxyacetone kinase from Citrobacter freundii 28 (Scheme 1B). These kinase enzymes were therefore combined into two step cascades with the active EcDERA variants.