A 9-year-old boy is diagnosed with acute lymphoblastic leuke…

A 9-year-old boy is diagnosed with acute lymphoblastic leukemia (ALL). He is started on a multidrug chemotherapy regimen that includes L-asparaginase. Two weeks later, he develops fatigue, easy bruising, and mild confusion. Laboratory studies show: serum albumin levels are decreased and ammonia levels are increased. Which of the following best describes the mechanism of action of this drug?