Sandbox Reserved 1846: Difference between revisions
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== Structural Overview == | == Structural Overview == | ||
<scene name='10/1075246/4eb0_helix_sheet/1'> | <scene name='10/1075246/4eb0_helix_sheet/1'>Secondary Structures</scene> | ||
=== Catalytic Triad === | === Catalytic Triad === | ||
LCC catalyzes the breakdown of PET using a classic serine hydrolase mechanism involving a <scene name='10/1075246/Catalytic_triad3/1'>catalytic triad</scene> of Ser165, His242, and Asp210. The reaction begins when His242 deprotonates Ser165, which activates it as a nucleophile. Ser165 then attacks the carbonyl carbon of an ester bond in the PET polymer. This forms a tetrahedral intermediate. This intermediate is stabilized by an oxyanion hole. The oxyanion hole is formed by the backbone amides of Met166 and Tyr95. The intermediate collapses; one product is released and an acyl-enzyme intermediate is formed. A water molecule, activated by His242, then attacks the acyl-enzyme, releasing the second product and resetting the enzyme’s active site. | LCC catalyzes the breakdown of PET using a classic serine hydrolase mechanism involving a <scene name='10/1075246/Catalytic_triad3/1'>catalytic triad</scene> of Ser165, His242, and Asp210. The reaction begins when His242 deprotonates Ser165, which activates it as a nucleophile. Ser165 then attacks the carbonyl carbon of an ester bond in the PET polymer. This forms a tetrahedral intermediate. This intermediate is stabilized by an oxyanion hole. The oxyanion hole is formed by the backbone amides of Met166 and Tyr95. The intermediate collapses; one product is released and an acyl-enzyme intermediate is formed. A water molecule, activated by His242, then attacks the acyl-enzyme, releasing the second product and resetting the enzyme’s active site. | ||
