TABLE 2.

Observed rate constants (K_obs, min⁻¹ μm⁻¹) of interdomain electron transfer as a function of environmental ionic strength

Ncb5or-b₅ or Cyb5A (1.4 μm each) was reduced by Ncb5or-b₅R or Cyb5R3, respectively, in the presence of excess NADH (50 μm) in buffer with various ionic strength (pH 7.0, no air).

Buffer	Ionic strength, μ	Cyb5A/Cyb5R3	Ncb5or-b5/Ncb5or-b5R
	m
i	0.009	1400 ± 90a	4.20 ± 0.17b
ii	0.108	331 ± 16a	1.13 ± 0.06b

^a 0.56 nm enzyme used.

^b 140 nm enzyme used..