Triad

... and glutamic acid peptidases) nucleophilic so that it can attack the peptide carbonyl group. One way to make a nucleophile is by a catalytic triad, where a histidine residue is used to activate serine, cysteine or threonine as a nucleophile. [edit] Occurrence Proteases occur naturally in ...

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... world has experienced, however, there has been no total such break down and comparative population crash resulting from crowding. The Malthusian triad of war, disease and starvation has somewhat crashed populations, but not behavioral deterioration as such. In us, it would seem, the increase ...

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