Table 2.

Activities of NfnI and NfnII

S.D. values were derived from three technical measurements.

Electron donors	Electron acceptors	NfnI activity	NfnII activity
		units mg−1	units mg−1
NADPH	NAD+ + Fdox	21 ± 3	<0.01a
NADPH	BV	1277 ± 165	408 ± 60
NADH	BV	61 ± 7	1.1 ± 0.3
NADPH	Fdox	0.7 ± 0.01	<0.01a
Fd70redb	NADP+	0.4 ± 0.2	5.0 ± 0.8
Fd70redb	NAD+	0.7 ± 0.2	0.6 ± 0.2

^a Below detection limit of 0.01 units mg⁻¹.

^b Chemically reduced by ∼70% with titanium citrate.