TABLE 3.

Substrate specificity of M. jannaschii I-1-Pase

Substratea	Relative activity (%)
dl-myo-I-1-P	100
d-myo-I-1-P	96
myo-Inositol-2-phosphate	15
β-Glycerol phosphate	80
α-d-Glucose-1-phosphate	68
d-Glucose-6-phosphate	0
d-Fructose-1-phosphate	0
5′-AMP	0
NAD+	0
2′-AMP	600
pNPP	120

^aThe assay mixture contained 2.5 mM substrate, 10 mM MgCl₂ in 50 mM Tris HCl (pH 8); enzyme (0.4 μg) was added, and the sample was incubated for 1 min at 100°C. Errors in enzyme activity were 3 to 5%.