TABLE 4.

Effects of Tyr97 mutation of ST0452 protein from S. tokodaii and Tyr103 mutation of GlmU from E. coli strain K-12 on GlcNAc-1-P UTase activities^a

Protein	Specific activity (μmol/min/mg protein)	Relative activity (%)
ST0452
Wild type	15.08 ± 0.34	100.0
Y97A	27.52 ± 0.22	182.5
Y97N	67.11 ± 3.39	445.0
Y97V	53.79 ± 0.65	356.7
EcGlmU
Wild type	75.63 ± 4.11	100.0
Y103A	93.97 ± 1.96	124.2
Y103N	99.80 ± 7.38	132.0
Y103V	52.65 ± 2.82	69.6

^aAll experiments were repeated three times.