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Summary
DescriptionTriad chemical mech.png
English: A catalytic triad charge-relay system as commonly found in proteases. The acid residue (commonly glutamate or aspartate) aligns and polarises the base (usually histidine) which activates the nucleophile (often serine or cysteine, occasionally threonine). The catalytic triad reduces the pKa of the nucleophilic residue which then performs a nucleophilic attack on the substrate.
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