InterPro domain: IPR000304

Pyrroline-5-carboxylate reductase (P5CR) ( 1.5.1.2 ) [ 1 , 2 ] is the enzyme that catalyses the terminal step in the biosynthesis of proline from glutamate, the NAD(P) dependent oxidation of 1-pyrroline-5-carboxylate into proline. This enzyme is also able to convert delta-1-piperideine-6-carboxylate (P6C) into pipecolic acid [ 3 ]; this activity is part of pathway for the biosynthesis of the cyclic tetrapeptide apicidin F in the fungus Fusarium fujikuroi [ 4 ]. This entry also includes the pyrroline-5-carboxylate reductase ucsG from Acremonium sp., which is part of the gene cluster that mediates the biosynthesis of UCS1025A, a member of the pyrrolizidinone family that is a strong telomerase inhibitor and displays potent antibacterial and antitumor properties [ 5 ].

1. A soybean gene encoding delta 1-pyrroline-5-carboxylate reductase was isolated by functional complementation in Escherichia coli and is found to be osmoregulated. Mol. Gen. Genet. 221, 299-305
2. Comparison of proC and other housekeeping genes of Pseudomonas aeruginosa with their counterparts in Escherichia coli. Gene 86, 107-11
3. Human pyrroline-5-carboxylate reductase (PYCR1) acts on Δ(1)-piperideine-6-carboxylate generating L-pipecolic acid. J. Inherit. Metab. Dis. 37, 327-32
4. Apicidin F: characterization and genetic manipulation of a new secondary metabolite gene cluster in the rice pathogen Fusarium fujikuroi. PLoS ONE 9, e103336
5. Genome Mining and Assembly-Line Biosynthesis of the UCS1025A Pyrrolizidinone Family of Fungal Alkaloids. J. Am. Chem. Soc. 140, 2067-2071