TABLE 1

Kinetic data for the reduction of two hydroxylamines (HA) and an amidoxime by human recombinant b5R and cyt b5 compared with that seen in pooled HLM All reactions were performed in PBS, pH 7.4, with 1 mM NADH, under conditions approximating linear kinetics. Velocity data are expressed in nanomoles per total milligrams of protein per minute. Data represent two to three experiments performed in duplicate for each condition, and are given as means ± S.E.


Substrate

Apparent Km (μM)

Vmax (nmol/mg/min)
HLM
b5R/cyt b5
HLM
b5R/ cyt b5
Sulfamethoxazole-HA 363 ± 31 392 ± 45 1.93 ± 0.07 455 ± 23
Dapsone-HA 357 ± 62 395 ± 95 1.26 ± 0.09 205 ± 24
Benzamidoxime
629 ± 116
515 ± 149
3.05 ± 0.36
226 ± 31