Table 3.

Catalytic properties of the enriched SdhABE (MFR) complex.

					Specific activities (U mg−1)
Electron donor	E (mV)	Electron acceptor	E (mV)	ΔE (mV)	MFR	QFR
Reduced benzylviologen	−374a	Fumarate	25b	−399	16.5	59.0
Succinate	25b	Methylene blue	11c	14	< 0.01	28.8
Succinate	25b	Ferricenium	380d	−355	< 0.01	14.6
Succinate	25b	DCPIP	217e	−192	< 0.01
Succinate	25b	DMN	−35f	60	< 0.01
Succinate	25b	EQ-0	56g	−31	< 0.01
DMNH2	−35f	Fumarate	25b	−60	0.1	7.4
TMNH2	−124h	Fumarate	25b	−149	0.4	1.0
5-MMKH2-6 analogue	−124h	Fumarate	25b	−149	0.2
8-MMKH2-6 analogue	−124h	Fumarate	25b	−149	0.9
CoB-SH/CoM-SH	−143i	Fumarate	25b	−168	<0.01

^aWardman (1991).

^bOhnishi et al. (2000).

^cClark (1960).

^dLehman et al. (1990).

^eHägerhäll (1997).

^fin situ potential in QFR, Madej et al. (2006a).

^gMadej et al. (2006b), Lancaster et al. (2008).

^hThis work.

ⁱTietze et al. (2003).

Selected corresponding values of purified QFR (Lancaster et al 2000; 2001; this work) are included for comparison.