Fig. 5

a GCS activity assay confirming the necessity of THF for the operation of the whole system. “Normal Group” refers to a GCS reaction mixture as specified in the Materials and Methods section without missing any reaction components and enzymes. “Without Enzyme” refers to a reaction mixture containing the same concentrations of substrates except that no GCS enzymes were added. “Without THF” refers to a reaction mixture containing all reaction components and enzymes except for THF. b Formaldehyde formation in the overall GCS reaction catalyzed by T-protein at concentrations of 5, 10, 25, 50, and 80 μM from G1 to G5, respectively, after 5 h. Other reaction components and enzymes were the same as described in the Materials and Methods section