EC Number |
Reaction |
Reference |
---|
3.5.1.103 | 1-O-(2-acetamido-2-deoxy-alpha-D-glucopyranosyl)-1D-myo-inositol + H2O = 1-O-(2-amino-2-deoxy-alpha-D-glucopyranosyl)-1D-myo-inositol + acetate |
- |
- |
3.5.1.103 | 1-O-(2-acetamido-2-deoxy-alpha-D-glucopyranosyl)-1D-myo-inositol + H2O = 1-O-(2-amino-2-deoxy-alpha-D-glucopyranosyl)-1D-myo-inositol + acetate |
general acid-base pair mechanism with the side chain of Asp-15 functioning as the general base catalyst and His-144 serving as the general acid catalyst, whereas the side chain of Tyr-142 probably assists in polarizing substrate/stabilizing the oxyanion intermediate. Tyr-142 is a dynamic side chain that plays key roles in catalysis, modulating substrate binding, chemistry, and product release |
720006 |
3.5.1.103 | 1-O-(2-acetamido-2-deoxy-alpha-D-glucopyranosyl)-1D-myo-inositol + H2O = 1-O-(2-amino-2-deoxy-alpha-D-glucopyranosyl)-1D-myo-inositol + acetate |
proposed catalytic mechanism of MshB, overview. MshB uses a general acid-base mechanism in which Asp15 and His144 act as the general base and acid catalysts respectively, while Tyr142 plays a dynamic role that includes stabilization of the oxyanion intermediate |
734822 |
3.5.1.103 | 1-O-(2-acetamido-2-deoxy-alpha-D-glucopyranosyl)-1D-myo-inositol + H2O = 1-O-(2-amino-2-deoxy-alpha-D-glucopyranosyl)-1D-myo-inositol + acetate |
proposed catalytic mechanism: the substrate binds to MshB so that the carbonyl oxygen of the acetyl group replaces the second water molecule on the Zn2+ ion. This leaves the first water molecule in an ideal position for general base-assisted nucleophilic attack of the carbonyl carbon of the acetyl group. The general base is the carboxylate of Asp-15. The tetrahedral transition state would then have a negatively charged oxygen atom that is stabilized by the positively charged Zn2+ and by the imidazolium side chain of His-144. Proton transfer to the nitrogen of the leaving group (GlcN-Ins) would be via the general acid function of the carboxyl group of Asp-15 |
-, 698727 |