Nucleophilic acyl substitution reaction biological example

Biochemistry is carbonyl chemistry. Almost all metabolic processes used by living organisms involve one or more of the four fundamental carbonyl-group reactions. For example, the digestion and metabolic breakdown of all the major classes of food molecules—fats, carbohydrates, and proteins—take place by nucleophilic addition reactions, nucleophilic acyl substitutions, a substitutions, and carbonyl condensations. Similarly, hormones and other crucial biological molecules are built up from smaller precursors by these same carbonyl-group reactions. 

The hydrolysis of a carboxylic acid derivative is but one example of a nucleophilic acyl substitution. Nucleophilic acyl substitutions connect the various classes of carboxylic acid derivatives, with a reaction of one class often serving as preparation of another. These reactions provide the basis for a large number of functional group transformations both in synthetic organic chemistry and in biological chemistry. 

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