Crystallization (Comment) | Organism |
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to 1.95 A resolution. The enzyme has a stacked alphabetabetaalpha fold comprising the large and small subunits, similar to the folds seen in members of the N-terminal nucleophile hydrolase superfamily. The active site residue Thr391, the N-terminal residue of the small subunit, is located in the groove, from which the pocket for gamma-glutamyl moiety binding follows. The gamma-glutamyl-enzyme intermediate and the structure of the complex with L-glutamate reveal how the gamma-glutamyl moiety and L-glutamate are recognized by the enzyme. A water molecule is seen on the carbonyl carbon of the gamma-glutamyl-Thr391 O bond in the intermediate that is to be hydrolyzed. The residues essential for enzymic activity, i.e. Arg114, Asp433, Ser462, and Ser463, are all involved in the binding of the gamma-glutamyl moiety | Escherichia coli |
Organism | UniProt | Comment | Textmining |
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Escherichia coli | P18956 | - |
- |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
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glutathione + H2O | - |
Escherichia coli | L-cysteinylglycine + L-glutamate | the reaction consists of two steps. First the active O atom of Thr391 attacks the carbonyl carbon atom of the gamma-glutamyl compound to form the gamma-glutamyl-enzyme intermediate, and then the gamma-glutamyl moiety is transferred to another substrate, i.e. reaction of EC 2.3.2.2, or the gamma-glutamyl-enzyme bond is hydrolyzed to reform the resting enzyme. The second step of the reaction, the hydrolysis of the intermediate, is much slower than the first reaction step | ? |