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Pepsin A (EC3.4.23.1, pepsin, lactated pepsin, pepsin fortior, fundus-pepsin, elixir lactate of pepsin, P I, lactated pepsin elixir, P II, pepsin R, pepsin D) is an enzyme. This enzyme catalyses the following chemical reaction
Preferential cleavage: hydrophobic, preferably aromatic, residues in P1 and P1' positions. Cleaves Phe-Val, Gln-His, Glu-Ala, Ala-Leu, Leu-Tyr, Tyr-Leu, Gly-Phe, Phe-Phe and Phe-Tyr bonds in the B chain of insulin
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Pepsin + inhibitor (l.blue), Human