. Author manuscript; available in PMC: 2015 Jan 21.

Published in final edited form as: Chem Soc Rev. 2014 Jan 21;43(2):676–706. doi: 10.1039/c3cs60249d

Table 5.

Kinetic parameters of periplasmic nitrate reductases

Class Organism		Subunit	Substrate	K_m (µM)	k_cat (s⁻¹)	V_max (µmol min⁻¹ mg⁻¹)	Assay method^a	Ref.
α	Magnetospirillum magnetotacticum	NapAB	Nitrate	3.2	2.5		MV	338
	Rhodobacter sphaeroides	NapAB	Nitrate	170		25	MV	186
		NapA	Nitrate	45		5.9	MV
		NapAB	Nitrate	30			PFV	221
		NapAB	Nitrate	100 (pH 7–8)			PFV	339
				140 (pH 8.4)
				185 (pH 9)
		NapAB	Nitrate	97			PFV	340
		NapAB (WT)	Nitrate	410		13.1	MV	205
		NapAB (M153A)	Nitrate	3200		13.2	MV
		NapAB (R392A)	Nitrate	65 500		11.9	MV
		NapAB (Q384N)	Nitrate	1100		9	MV
		NapAB	Nitrate	80			PFV	247
	Paracoccus pantotrophus (Thiospera	NapAB	Nitrate	240		3.41 (Mo grown cell)	MV	341
	pantothropha, Paracoccus denitrificans)	NapAB	Nitrate	112	58		MV
		NapAB	Nitrate	45			PFV	222
		NapAB		3910		0.05 (W grown cell)	MV	341
		NapAB	Nitrate		11–5.5 ms	95^c	MV	342
		NapAB	Nitrate	1300	240		MV and dithionite	212
		NapAB	Azide^b	11 000 (K_i)			MV, dithionite
		NapAB	Cyanide^b	1300 (K_i)			MV, dithionite
		NapAB	Thiocyanate^b	4000 (K_i)			MV	206
γ	Escherichia coli	NapAB	Nitrate			~ 0.140 (Mo grown cell)	MV	341
		NapAB	Nitrate			0.07 (W grown cell)	MV
	Aliivibrio (Achromobacter, Vibrio) fischeri	NapAB	Nitrate	65		1.5	BV	343
β	Alcaligenes eutrophus (Ralstonia	NapAB	Nitrate	120			BV	280
	eutropha, Cupriavidus necator)	NapAB	Nitrate	88			PFV + MV	344
δ	Desulfovibrio desulfuricans	NapA	Nitrate	32		18.6^c	MV	210

In most cases a reduced viologen dye (methyl viologen, MV or benzyl viologen, BV) was used as an electron donor and probed spectrophotometrically.

Inhibitor.

Reported as specific activity.