The enzyme galactarate dehydratase () catalyzes the chemical reaction
This enzyme belongs to the family of lyases, specifically the hydro-lyases, which cleave carbon-oxygen bonds. The systematic name of this enzyme class is <small>D</small>-galactarate hydro-lyase (5-dehydro-4-deoxy-<small>D</small>-glucarate-forming). This enzyme is also called <small>D</small>-galactarate hydro-lyase. This enzyme participates in ascorbate and aldarate metabolism.