FIG 5.

In vitro characterizations of SaM1PDH enzymatic activities. (A) pH dependence of SaM1PDH oxidoreductase activities. (B) Salt concentration dependence of SaM1PDH oxidoreductase activities. In the experiments whose results are presented in panels A and B, M1P oxidation (blue) and F6P reduction activities (red) of SaM1PDH were measured by monitoring changes in absorbance of NADH at 340 nm under conditions of (A) various pHs (5.0 to 11.5) and (B) various NaCl concentrations (0 to 300 mM). (C) pH dependence of SaM1PDH reductase activity at 200 mM NaCl. F6P reduction activity of SaM1PDH was measured by monitoring changes in absorbance of NADH at 340 nm in the presence (red) and absence (Ctrl; black) of 200 mM NaCl as a control. In panels A to C, oxidoreductase activities of SaM1PDH were normalized against the maximal enzymatic capacities (indicated by thin vertical lines) measured under each set of experimental conditions and are expressed as percent activity. Each experiment was done in triplicate, and data points were presented as means (dots) ± standard deviations of the means (whiskers). Solid lines connect data points.