The enzyme, found in green sulfur bacteria, some cyanobacteria and some actinobacteria, introduces additional double bonds to the carotenoid β-end group, leading to aromatization of the ionone ring. As a result, one of the methyl groups at C-1 is transferred to position C-2. It is involved in the biosynthesis of carotenoids with φ-type aromatic end groups such as chlorobactene, β-isorenieratene, and isorenieratene.
The enzyme appears in viruses and cellular organisms
The enzyme, found in green sulfur bacteria, some cyanobacteria and some actinobacteria, introduces additional double bonds to the carotenoid beta-end group, leading to aromatization of the ionone ring. As a result, one of the methyl groups at C-1 is transferred to position C-2. It is involved in the biosynthesis of carotenoids with phi-type aromatic end groups such as chlorobactene, beta-isorenieratene, and isorenieratene.
Substrates: enzyme is responsible for the conversion of beta-carotene via beta-isorenieratene to isorenieratene by a desaturation/methyltransferation mechanism. Upon introduction of two additional double bonds leading to amortization of the ionone ring, one of the methyl groups of C-1 (and also 1' at the other side) is lost and transferred to position 2 Products: -
a CrtU mutant accumulates gamma-carotene. The growth rates of the mutant strain shows no significant deviation from the wild-type growth rate at any light intensity
a CrtU mutant accumulates gamma-carotene. The growth rates of the mutant strain shows no significant deviation from the wild-type growth rate at any light intensity
expression of CrtU in the beta-carotene ketolase (crtO) knockout Rhodococcus erythropolis host produces higher purity chlorobactene than expression in the wild-type Rhodococcus host. Yeast extract medium supplemented with fructose gives the highest total yield of chlorobactene. In a 10-l fermentor, about 18 mg of chlorobactene is produced
Kruegel, H.; Krubasik, P.; Weber, K.; Saluz, H.; Sandmann, G.
Functional analysis of genes from Streptomyces griseus involved in the synthesis of isorenieratene, a carotenoid with aromatic end groups, revealed a novel type of carotenoid desaturase