The Active Site of a Certain Enzyme Contains a Serine

question 55

Multiple Choice

The active site of a certain enzyme contains a serine residue.When the enzyme is incubated for a short time with its substrate,a form of the enzyme in which the active site serine is acetylated can be isolated and purified.In the native protein the serine is never found to be acetylated.This information supports ________.

• A)a covalent catalysis mode
• B)intermediate state stabilization effects
• C)the acid-base catalysis mode
• D)a polar group catalytic mechanism

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