The following diagram depicts the tetrahedral active site intermediate formation during serine protease catalyzed peptide bond hydrolysis. Aspartate (Asp), histidine (His), and serine (Ser) are amino acids of the serine protease, which are close to each other and can interact to catalyze the breakdown of certain peptide bonds in proteins. The protein is R'NHCOR in the diagram below. You can see hydrogen bonds between the enzyme's Asp and His, and also the His is taking away a hydrogen from the Ser hydroxyl group. Which of the following statements best describes the Ser attack on the peptide bond?

MCQS on the biological importance of organic molecules. Topics include bioorganic mechanisms, chirality, lipids, carbohydrates, animo acids, peptides, proteins, nucleic acids, enzymes, coenzymes, and coupled reactions, and lipid, carbohydrate, amino acid, and nucleotide metabolism.