Delta 1-pyrroline-5-carboxylate dehydrogenase in the bovine ciliary body and iris

Delta 1-pyrroline-5-carboxylate dehydrogenase extracted from the combined ciliary body and iris of bovine eyes was studied biochemically. The enzyme was purified 120-fold. The partially purified enzyme had broad optimum at pH 8.0. Apparent Km values for DL-delta 1-pyrroline-5-carboxylate and NAD were 0.14 and 0.18 mM, respectively. The enzyme activity was strongly inhibited by GABA, proline, hydroxyproline, and glutamine.