<p> The delta(1)-pyrroline-5-carboxylate synthetase (<db_xref db="EC" dbkey="1.5.1.12"/>) a mitochondrial inner membrane, ATP- and NADPH-dependent, bifunctional enzyme, catalyzes the reduction of glutamate to delta1-pyrroline-5-carboxylate, a critical step in the de novo biosynthesis of proline and ornithine. It is the rate-limiting enzyme in proline biosynthesis and is subject to feedback inhibition by proline.<reaction> 1-pyrroline-5-carboxylate + NAD+ + H2O = L-glutamate + NADH </reaction> </p><p> This model represents one of several related branches of delta-1-pyrroline-5-carboxylate dehydrogenase.</p> Delta-1-pyrroline-5-carboxylate dehydrogenase 2