Glutamate 5-kinase/delta-1-pyrroline-5-carboxylate synthase <p> L-glutamate 5-phosphotransferase, (gamma-glutamyl kinase, proB, <db_xref db="EC" dbkey="2.7.2.11"/>), catalyzes the first step in proline biosynthesis<reaction> ATP + L-glutamate = ADP + L-glutamate 5-phosphate.</reaction>the product of which rapidly cyclises to 5-oxoproline and phosphate.</p><p>This entry also includes delta-1-pyrroline-5-carboxylate synthase, an enzyme that in the N-terminal section belongs to the glutamate 5-kinase family. Glutamate 5-kinase hits the full length of this model, but delta 1-pyrroline-5-carboxylate synthetase does not hit the C-terminal 100 residues.</p>