This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-NH group of donors with NAD+ or NADP+ as acceptor. The systematic name of this enzyme class is N2-(D-1,3-dicarboxypropyl)-L-arginine:NADP+ oxidoreductase (L-arginine-forming). Other names in common use include D-nopaline synthase, nopaline dehydrogenase, nopaline synthase, NOS, 2-N-(D-1,3-dicarboxypropyl)-L-arginine:NADP+ oxidoreductase, and (L-arginine-forming). This enzyme participates in arginine and proline metabolism.
References
Kemp JD, Sutton DW, Hack E (1979). "Purification and characterization of the crown gall specific enzyme nopaline synthase". Biochemistry. 18 (17): 3755–60. doi:10.1021/bi00584a017. PMID476084.