An enzyme cleaving l-argininosuccinate nonhydrolytically to l-arginine and fumarate; a deficiency of this enzyme leads to argininosuccinoaciduria; a key step in the urea cycle. SYN: argininosuccinase.
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ar·gi·ni·no·suc·cin·ate ly·ase (ahr″jĭ-ne″no-sukґsĭ-nāt liґās) [EC 4.3.2.1] an enzyme of the lyase class that catalyzes the cleavage of argininosuccinate to form fumarate and arginine. The reaction is part of the urea cycle in the liver (see illustration at urea cycle, under cycle). Deficiency of the enzyme, an autosomal recessive trait, results in argininosuccinicaciduria. Called also argininosuccinase.Medical dictionary. 2011.