. 2011 Sep 14;286(45):39224–39235. doi: 10.1074/jbc.M111.286351

TABLE 2.

Thermodynamic, kinetic, and catalytic parameters for WT and Trp⁶⁶ variants of B. subtilis NOS

Protein	Heme midpoint potentials^a	Autooxidation of FeO₂ with H₂T^a	Arg to NOHA^a,b, k_cat1	NOHA to NO^a,b, k_cat2	Rate of NOHA formation^a,c	Rate of Fe(II)-NO oxidation^a,b, k_ox	Product yield in single turnover reactions^a,c (product/heme)		NO synthesis supported by FLDR/YkuN^d (NO/heme, with H₄T)
Protein	Heme midpoint potentials^a	Autooxidation of FeO₂ with H₂T^a	Arg to NOHA^a,b, k_cat1	NOHA to NO^a,b, k_cat2	Rate of NOHA formation^a,c	Rate of Fe(II)-NO oxidation^a,b, k_ox	l-Arg	NOHA	NO synthesis supported by FLDR/YkuN^d (NO/heme, with H₄T)
	mV	s⁻¹
W66H	−302	0.12	2.7	2.0	2.9	0.063	0.31	0.58	7.5
Protein	−361	0.42	15.7	4.3	4.3	0.092	0.27	0.60	9.9
W66F	−427	2.8	37	26	17	1.17	0.23	0.59	3.9

^a Determined at 10 °C.

^b Results from stopped-flow spectroscopy.

^c Results from chemical quench and HPLC.

^d Determined at room temperature.