FIG. 3.

Enzymatic reactions and assays. (A) Coupled assays were used to establish the reaction specificity of d-glycerate phosphorylation by TM1585: (i) detection of 2PG was monitored at 340 nm by coupling to NADH oxidation via three consecutive reactions catalyzed by ENO, PYK, and lactate dehydrogenase (LDH); (ii) no indication of 3PG formation was obtained in the alternative assay with the addition of PGK and glyceraldehyde-3-phosphate dehydrogenase (GAPDH). (B) Biochemical transformations in the T. maritima serine degradation pathway and the assays used to assess the enzymatic activities of GK-II (TM1585) and of the two additional enzymes, SAT (TM1400) and HPR (TM1401).