ID   1.13.11.51
DE   9-cis-epoxycarotenoid dioxygenase.
AN   NCED.
AN   Nine-cis-epoxycarotenoid dioxygenase.
AN   VP14.
CA   (1) A 9-cis-epoxycarotenoid + O(2) = 2-cis,4-trans-xanthoxin + a 12'-apo-
CA   carotenal.
CA   (2) 9-cis-violaxanthin + O(2) = 2-cis,4-trans-xanthoxin + (3S,5R,6S)-5,6-
CA   epoxy-3-hydroxy-5,6-dihydro-12'-apo-beta-caroten-12'-al.
CA   (3) 9'-cis-neoxanthin + O(2) = 2-cis,4-trans-xanthoxin + (3S,5R,6R)-5,6-
CA   dihydroxy-6,7-didehydro-5,6-dihydro-12'-apo-beta-caroten-12'-al.
CF   Iron.
CC   -!- Acts on 9-cis-violaxanthin and 9'-cis-neoxanthin but not on the all-
CC       trans isomers.
CC   -!- In vitro, it will cleave 9-cis-zeaxanthin.
CC   -!- Catalyzes the first step of abscisic-acid biosynthesis from
CC       carotenoids in chloroplasts, in response to water stress.
CC   -!- The other enzymes involved in the abscisic-acid biosynthesis pathway
CC       are EC 1.1.1.288, EC 1.2.3.14 and EC 1.14.13.93.
DR   O24592, NCED1_MAIZE;  Q9M6E8, NCED1_PHAVU;  O49505, NCED2_ARATH;
DR   Q9LRR7, NCED3_ARATH;  Q9C6Z1, NCED5_ARATH;  Q9LRM7, NCED6_ARATH;
DR   Q9M9F5, NCED9_ARATH;
//