Table 3.

Calculated tunnelling rates and some experimental rates for forward electron transfer between some redox centres in cytochrome oxidase. (Driving forces use the average midpoints of table 1. The default generic reorganization energy is 0.7 eV. The relevant packing densities in oxidase are higher than the generic protein default value of 0.76.)

	CuA→a		a→a3		CuA→a3
R (Å)	16.1 Å		7.0		18.9
ΔG° (eV)	−0.02		−0.02		−0.04
λ (eV)	default (0.7)	default	default	1.13	1.3
ρ	default (0.76)	0.87	default	0.82	default	0.79	default	0.79
rate calc.	3.0×103	8.7×104	6.5×108	1.4×109	87	250	4	4
rate meas.	2×104 a	7×108 b	4 c

^aAdelroth et al. (1995).

^bPilet et al. (2004).

^cKannt et al. (1999).