TABLE 2.

Mutation of critical residues affects YwqE enzymatic activity

YwqE protein or mutant	% Relative activity ± SEa
Wild type	100.0 ± 8.4
D3A	8.1 ± 0.7
H5A	9.5 ± 0.8
H7A	6.3 ± 0.5
H42A	6.8 ± 0.6
H136A	7.7 ± 0.7
D194A	5.4 ± 0.5
H196A	4.1 ± 0.3

^aThe assay contained 2 μg YwqE and 3 mM of pNPP as the substrate. The buffer used was 50 mM HEPES, pH 8.0, and 1 mM MnCl₂.