Two Fusarium copper radical oxidases with high activity on aryl alcohols

Table 1 Substrate specificity of FgrAAO and FoxAAO

Substrate	FgrAAO			FoxAAO
Substrate	K_M (mM)	k_cat (s⁻¹)	k_cat/K_M (M⁻¹ s⁻¹)	K_M (mM)	k_cat (s⁻¹)	k_cat/K_M (M⁻¹s⁻¹)
Carbohydrates
Galactose	1700 ± 150	21 ± 1.0	12	1600 ± 150	23 ± 1.2	14
Galactose	450 ± 74	36 ± 1.2	79	620 ± 57	19 ± 0.35	31
Fructose	460 ± 91	9.7 ± 0.55	21	510 ± 82	16 ± 0.72	31
Polyols
Glycerol	2200 ± 360	17 ± 1.2	7.7	2700 ± 403	24 ± 1.6	8.8
Aryl alcohols
Benzyl alcohol	86 ± 12	37 ± 2.8	430	30 ± 19	31 ± 4.2	1000 (350 ± 20)^a
Cinnamyl alcohol	n.d.^b	n.d.^b	3000	n.d.^b	n.d.^b	3200
4-Methoxybenzyl (p-anisyl) alcohol	59 ± 7.2	32 ± 1.8	540	51 ± 12	34 ± 2.9	290
3-Methoxybenzyl (m-anisyl) alcohol	6.5 ± 1.5	52 ± 1.5	8000	6.7 ± 0.59	34 ± 1.7	5100
3,4-Dimethoxybenzyl (veratryl) alcohol	3.7 ± 0.75	41 ± 4.0	11000	3.0 ± 0.24	25 ± 1.2	8300
Furans
HMF	14 ± 2.6	29 ± 1.7	2100	17 ± 4.9	26 ± 2.6	1500
DFF	10 ± 2.9	3.6 ± 0.27	360	3.7 ± 1.0	1.4 ± 0.13	380
HMFCA	4.4 ± 0.90	3.8 ± 0.33	860	3.1 ± 0.31	5.2 ± 0.14	1700

Errors represent the standard deviation from the mean values
^aK_M, k_cat, and k_cat/K_M values calculated from fitting of the standard Michaelis–Menten equation to the data. Value in parentheses is the k_cat/K_M value obtained from a linear fit to the data in the substrate range 1–50 mM. Fitting of the data with a modified Michaelis–Menten equation accounting for substrate inhibition was unsuccessful due to very high errors on individual parameters (see Additional file 1: Figure S6)
^bIndividual K_M and k_cat values not determinable due to substrate solubility limitations; k_cat/K_M values obtained from slope of linear v₀ versus [S] plots (Additional file 1: Figure S6)

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