Isochorismate pyruvate lyase: Difference between revisions
Michal Harel (talk | contribs) No edit summary |
Michal Harel (talk | contribs) No edit summary |
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==Significance== | ==Significance== | ||
This enzyme unlike others does not catalyze forming covalent enzyme-substrate intermediate or acid-base catalysis. Claisens rearrangement takes place, instead. The substrate is stabilized in an energitically unfavorable pseudoaxial conformation forcing the vanderwaals contact, producing steric strain on the substrate and provides electrostatic stabilization of the transition state. Lys 42 and Gln 90 are positioned to stabilize the developing negative charge of the polar transition product in the chorismate mutase reaction and the pyruvate byproduct in the IPL reaction. therefore the ordering of the active site loop shows induced fit of the enzyme upon substrate binding locks Lys 42 into place for catalysis. | This enzyme unlike others does not catalyze forming covalent enzyme-substrate intermediate or acid-base catalysis. Claisens rearrangement takes place, instead. The substrate is stabilized in an energitically unfavorable pseudoaxial conformation forcing the vanderwaals contact, producing steric strain on the substrate and provides electrostatic stabilization of the transition state. Lys 42 and Gln 90 are positioned to stabilize the developing negative charge of the polar transition product in the chorismate mutase reaction and the pyruvate byproduct in the IPL reaction. therefore the ordering of the active site loop shows induced fit of the enzyme upon substrate binding locks Lys 42 into place for catalysis. | ||