A student hydrolyses a polypeptide chain containing 50 amino acids. How many water molecules are required to completely break all the peptide bonds?

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Question

A student hydrolyses a polypeptide chain containing 50 amino acids. How many water molecules are required to completely break all the peptide bonds?

Accepted Answer

49 water molecules — A polypeptide of 50 amino acids contains 49 peptide bonds (one fewer than the number of monomers). Hydrolysis requires one water molecule per peptide bond, so 49 water molecules are needed. 50 water molecules would incorrectly assume one bond per monomer. 48 is two fewer than the number of bonds. 51 is more than the number of monomers.

Answer

48 water molecules

Answer

51 water molecules

Answer

50 water molecules

Answer

49 water molecules

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