Table 1. Kinetic Parameters of pIR23 and BacRedAm for Cyclohexanone, Hydrocinnamaldehyde, and Cinnamaldehyde with Different Amines^a.

			pIR23		BacRedAm
varied substrate	saturated substrates		Km (mM)	kcat (s–1)	Km (mM)	kcat (s–1)
cyclohexanone (1)	NADPH	cyclopropylamine (a)	10.12	3.47	13.32	5.12
		propargylamine (b)		0.31		3.75
		allylamine (c)		0.22		2.02
		methylamine (e)	12.35	0.94	11.41	4.74

			pIR23		BacRedAm
varied substrate	saturated substrates		Km (mM)	kcat (s–1)	Km (mM)	kcat (s–1)
hydrocinnamaldehyde (2)	NADPH	cyclopropylamine (a)	0.43	1.57	2.98	1.45
		propargylamine (b)	0.10	0.89	2.43	1.95
		allylamine (c)	0.33	1.00	3.32	2.01
		propylamine (d)	0.64	1.26	n.d.	n.d.
		methylamine (e)	0.32	0.46	2.12	0.61
		benzylamine (f)	0.89	0.81	2.14	0.10
		pyrrolidine (g)	0.64	1.84	2.54	0.13
		piperidine (h)	0.89	0.64	n.d.	n.d.

			pIR23		BacRedAm
varied substrate	saturated substrates		Km (mM)	kcat (s–1)	Km (mM)	kcat (s–1)
cinnamaldehyde (3)	NADPH	cyclopropylamine (a)	0.20	0.36	2.58	0.11
		propargylamine (b)	0.12	0.23	1.96	0.09
		allylamine (c)	0.33	0.27	1.89	0.10
		propylamine (d)	0.77	0.48	n.d.	n.d.
		methylamine (e)	0.27	0.13	2.54	0.04
		benzylamine (f)	0.29	0.15	2.45	0.08
		pyrrolidine (g)	0.25	0.77	3.34	0.20
		piperidine (h)	0.34	0.25	n.d.	n.d.

^aOne unit of activity = the amount of pure enzyme required to consume 1 μmol of NADPH per min. The initial rate activity measurements were performed at pH 7.5 (100 mM NaPi buffer), Temp = 30 °C; [NADPH] = 0.3 mM; [amine] = 80 mM. n.d.—not determined. Activity measurements were performed in triplicate; Table S2 (Supporting Information) provides data with error/standard deviation from the mean activity (k_cat) or mean K_m values.