ID 1.14.11.28 DE proline 3-hydroxylase. AN P-3-H. CA 2-oxoglutarate + L-proline + O2 = cis-3-hydroxy-L-proline + CO2 + CA succinate. CC -!- Unlike the proline hydroxylases involved in collagen biosynthesis CC (EC 1.14.11.2 and EC 1.14.11.7), this enzyme does not require CC ascorbate for activity although it does increase the activity of the CC enzyme. CC -!- The enzyme is specific for L-proline as D-proline, trans-4-hydroxy-L- CC proline, cis-4-hydroxy-L-proline and 3,4-dehydro-DL-proline are not CC substrates. DR P96010, P3H1_STRSQ ; O09345, P3H2_STRSQ ; //