Oxygen affinities of cellular enzymes expressed as the partial pressure of oxygen in mm Hg at which the enzyme rate is half maximum (Kmo2)
| Enzyme | Substrate | Kmo2 |
|---|---|---|
| Glucose oxidase | Glucose | 57 |
| Xanthine oxidase | Hypoxanthine | 50 |
| Tryptophan oxygenase | Tryptophan | 37 |
| Nitric oxide synthase | l-arginine | 30 |
| Tyrosine hydroxylase | Tyrosine | 25 |
| NADPH oxidase | Oxygen | 23 |
| Cytochrome aa3 | Oxygen | 0.05 |