. Author manuscript; available in PMC: 2011 Sep 20.

Published in final edited form as: Biochemistry. 2009 Mar 17;48(10):2237–2247. doi: 10.1021/bi802274f

Table 4.

Properties of Site-Directed Mutants of Dr0930^a.

Protein	color	metal content		k_cat (min⁻¹)	K_m (mM)	k_cat/K_m (M⁻¹ s⁻¹)
Protein	color	zinc	iron	k_cat (min⁻¹)	K_m (mM)	k_cat/K_m (M⁻¹ s⁻¹)
wild type	purple	0.71	0.52	0.072	1.4	0.83
F26G	black	0.85	0.34	0.55	8.3	1.1
C72I	purple	0.61	0.87	0.023	1.4	0.29
F26G/C72I	purple	0.64	0.81	1.14	2.7	7.7
Y98F	purple	1.17	0.38	0.06	1.8	0.55
F26G/C72I/Y97W/Y98F	yellow	0.41	0.66	-	-	0.91^b
G207D/R228H/L231H	purple	1.29	0.47	nd^c	nd	nd
F26G/C72I/Y97W/Y98F/G207D/R228H/L231H	yellow	0.62	0.27	nd	nd	nd

Hydrolysis of paraoxon at pH 9.0.

The enzyme was not saturated up to a concentration of paraoxon of 3 mM.

nd – not detectable.