FMO Content | Kinetic Parameters ofS-Oxidation1-a | |||||
---|---|---|---|---|---|---|
nmol FMO · mg−1 Protein | Percent FMO2 | Vmax | Km | Vmax/Km | R2 | |
hFMO2.1 | ||||||
1 | 0.85 | 5.2 | 23.2 | 1.46 | 15.9 | 0.99 |
2 | 2.27 | 13.8 | 14.3 | 1.01 | 14.2 | 0.96 |
mFMO2 | ||||||
1 | 1.30 | 7.9 | 33.7 | 1.53 | 22.1 | 0.97 |
2 | 0.99 | 6.0 | 40.4 | 1.48 | 27.2 | 0.98 |
FMO content was determined by flavin assay (Fader and Siegel, 1973). The nanomoles of FAD · milligram−1 associated with expressed control protein was subtracted from test proteins, and a 1 FAD/1 FMO molar ratio was assumed. Percent FMO2 was derived assuming 16.4 nmol of FAD · mg−1 of hFMO2.1 and mFMO2.
↵1-a Vmax = nanomoles · minute−1 · nanomole−1 of FMO;Km = millimolar determined at pH 8.5 using methimazole at 0.2, 0.5, 1.0, 2.0, and 5.0 mM; R2 = Lineweaver-Burke correlation coefficients.