Table 3.

ALDH‐ and ADH‐specific activities in Pyrococcus furiosus strains and bacterial crude extracts

Strain	ALDH activitya (acetyl‐CoA)		ADH activitya (acetaldehyde)
	NADH	NADPH	NADH	NADPH
Control strains
COM1	< 0.05	< 0.05	< 0.05	< 0.05b
ΔAOR	< 0.05	< 0.05	< 0.05	< 0.05b
AdhA	< 0.05	< 0.05	< 0.05	0.94
P. furiosus AdhE expression strains
Te‐AdhEA	0.58	< 0.05	0.48	1.66
Te‐AdhE	0.29	< 0.05	1.00	0.07
Tx‐AdhE	0.17	< 0.05	0.53	< 0.05
Gt‐AdhE	< 0.05	< 0.05	< 0.05	< 0.05
Dk‐AdhE	< 0.05	< 0.05	0.05	< 0.05
Af‐AdhE	< 0.05	< 0.05	0.05	< 0.05
Gs‐AdhE	< 0.05	< 0.05	< 0.05	< 0.05
Tc‐AdhE	< 0.05	< 0.05	0.06	< 0.05
Ct‐AdhE	< 0.05	< 0.05	< 0.05	< 0.05
Mutant AdhE expression strains
Te‐AdhE*	0.44	< 0.05	< 0.05	< 0.05
Tx‐AdhE*	0.72	< 0.05	< 0.05	< 0.05
AdhE in the native organism
C. thermocellum	4.96	0.06	19.42	< 0.05
T. sp. strain X514	0.18	0.02	1.09	3.38
T. ethanolicus	0.70	< 0.05	2.82	6.96

^aSpecific activities are listed as μmol NAD(P)H oxidized min⁻¹ mg⁻¹. The detection limit for these assays is ~0.05 U mg⁻¹.

^bADH activity in the forward reaction was not detected at 65°C; however, the reverse assay resulted in 0.2 U mg⁻¹ of ethanol oxidation using NADP as the electron acceptor at 80°C.