2.4.2 Measurement with pure Tmm
The amount of NADPH consumed and TMAO formed is assayed using the previously reported methods. The Michaelis-Menten equation is used for calculating Km and Vmax forTmm . The values for Km and Vmaxare calculated as 0.13 µM and 1.631 µM, respectively, when considering NADPH consumed in the reaction. The values for Km and Vmax are calculated as 0.08 µM and 0.85 µM, respectively, when the amount of TMAO formed in the reaction is monitored. Whereas activity measured through the current reported method is lower (figure 4). The Kmvalues indicate the substrate and enzyme interaction, and a lower value of Km suggests a better binding of Tmm with its native substrate, trimethylamine. Thus, our method is more accurate compared to NADPH-dependent assay.