TABLE 4.

Observed rate constants (min⁻¹ μm⁻¹) of cytochrome c reduction

Single enzyme or mixture was used to reduce cytochrome c (1.4 μm) in the presence of excess NADH (50 μm) and 5 mm phosphate (pH 7.0, no air). An enzyme concentration of 28 nm (each protein) was used in all cases. NA, not available.

	Cyb5R3	Ncb5or-b5R	Ncb5or-CS/b5R	Ncb5or
Cytochrome c alone	10.39 ± 0.50	9.32 ± 0.36	12.41 ± 0.57	34.70 ± 1.07
Cytochrome c + Ncb5or-b5	14.09 ± 0.64	9.69 ± 0.49	13.27 ± 0.39	NA