ID   1.3.99.39
DE   carotenoid phi-ring synthase.
CA   2 A + a carotenoid beta-end derivative = a carotenoid phi-end derivative
CA   + 2 AH2.
CC   -!- The enzyme, found in green sulfur bacteria, some cyanobacteria and
CC       some actinobacteria, introduces additional double bonds to the
CC       carotenoid beta-end group, leading to aromatization of the ionone
CC       ring.
CC   -!- As a result, one of the methyl groups at C-1 is transferred to
CC       position C-2.
CC   -!- It is involved in the biosynthesis of carotenoids with phi-type
CC       aromatic end groups such as chlorobactene, beta-isorenieratene,
CC       and isorenieratene.
DR   Q8KFK3, CRTU_CHLTE ;  P72449, CRTU_STRGR ;
//