Filling the gap in vitamin A research. Molecular identification of an enzyme cleaving beta-carotene to retinal.
Vitamin A and its derivatives (retinoids) are essential components in vision; they contribute to pattern formation during development and exert multiple effects on cell differentiation with important clinical implications. It has been known for 50 years that the key step in the formation of vitamin A is the oxidative cleavage of beta-carotene; however, this enzymatic step has resisted molecular analysis. A novel approach enabled us to clone and identify a beta-carotene dioxygenase from Drosophila melanogaster, expressing it into the background of a beta-carotene (provitamin A)-synthesizing and -accumulating Escherichia coli strain. The carotene-cleaving enzyme, identified here for the first time on the molecular level, is the basis of the numerous branches of vitamin A action and links plant and animal carotene metabolism.
von Lintig
J
J
Albert-Ludwig Universität Freiburg, Institut für Biologie I, Neurobiologie und Tierphysiologie, D-79104 Freiburg, Germany.
Vogt
K
K
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002384:Catalysis; D002851:Chromatography, High Pressure Liquid; D049308:Dioxygenases; D029721:Drosophila Proteins; D004331:Drosophila melanogaster / Q000201:enzymology; D004926:Escherichia coli / Q000201:enzymology; D008956:Models, Chemical; D008969:Molecular Sequence Data; D010105:Oxygenases / Q000378:metabolism*; D010940:Plant Proteins; D012172:Retinaldehyde / Q000378:metabolism*; D013054:Spectrophotometry, Atomic; D014801:Vitamin A / Q000502:physiology*; D019207:beta Carotene / Q000378:metabolism*; D050559:beta-Carotene 15,15'-Monooxygenase
D029721:Drosophila Proteins; D010940:Plant Proteins; C493360:ninaB protein, Drosophila; D019207:beta Carotene; D014801:Vitamin A; D010105:Oxygenases; D049308:Dioxygenases; C109043:9-cis-epoxy-carotenoid dioxygenase; D050559:beta-Carotene 15,15'-Monooxygenase; D012172:Retinaldehyde