Canthaxanthin biosynthesis by the conversion of methylene to keto groups in a hydrocarbon beta-carotene by a single gene.
Compounds that include (a) keto group(s) in a molecule are ubiquitous natural components. A novel gene involved in ketocompound biosynthesis, designated crtW, was isolated from the marine bacteria Agrobacterium aurantiacum and Alcaligenes PC-1 that produce ketocarotenoids such as astaxanthin. When this gene was introduced into Escherichia coli that accumulated beta-carotene due to the Erwinia carotenogenic genes, the E. coli transformants synthesized canthaxanthin, one of ketocarotenoids, which was identified after purification by its visible, FD-MS and 1H-NMR spectral analysis. It has been demonstrated for the first time that one gene encodes an enzyme "ketolase" that catalyzes the conversion of methylene groups of a hydrocarbon beta-carotene to keto groups for synthesizing canthaxanthin via echinenone.
Misawa
N
N
Central Laboratories for Key Technology, Kirin Brewery Co., Ltd., Kanagawa, Japan.
Kajiwara
S
S
Kondo
K
K
Yokoyama
A
A
Satomi
Y
Y
Saito
T
T
Miki
W
W
Ohtani
T
T
D000421:Alcaligenes / Q000235:genetics / Q000378:metabolism*; D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000378:metabolism*; D016644:Canthaxanthin / Q000096:biosynthesis*; D002338:Carotenoids / Q000378:metabolism*; D002876:Chromosomes, Bacterial; D003001:Cloning, Molecular; D004269:DNA, Bacterial / Q000302:isolation & purification / Q000378:metabolism; D004885:Erwinia / Q000235:genetics / Q000378:metabolism; D004926:Escherichia coli / Q000378:metabolism; D005798:Genes, Bacterial; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D008969:Molecular Sequence Data; D010105:Oxygenases / Q000096:biosynthesis / Q000737:chemistry / Q000378:metabolism*; D010957:Plasmids; D015183:Restriction Mapping; D012231:Rhizobium / Q000235:genetics / Q000378:metabolism*; D012623:Seawater; D017386:Sequence Homology, Amino Acid; D019207:beta Carotene
D001426:Bacterial Proteins; D004269:DNA, Bacterial; D019207:beta Carotene; D002338:Carotenoids; D016644:Canthaxanthin; D010105:Oxygenases; C093259:beta-carotene ketolase