opine metabolism octopine degradation GO:0019469 N2-(D-l-carboxyethyl)-L-arginine degradation UPa:UPA00737 PMID:8045881 Degradation of octopine (N2-(D-l-carboxyethyl)-L-arginine), the first opine discovered in 1927 in octopus muscle and later in crown gall tumors. It is also found in other cephalopod species and lamellibranchs. Octopine is the head member of the octopine family of opines. pathway