Metabolic engineering of astaxanthin production in tobacco flowers

• Published in: Nature biotechnology Vol. 18; no. 8; pp. 888 - 892
• Main Authors: Hirschberg, Joseph, Mann, Varda, Harker, Mark, Pecker, Iris
• Format: Journal Article
• Language: English
• Published: New York, NY Nature 01.08.2000; Nature Publishing Group
• Subjects: Algae; Animals; Aquaculture; astaxanthin; b-carotene ketolase; Bacteria; Bacterial Proteins - genetics; beta Carotene - analogs & derivatives; beta Carotene - biosynthesis; beta Carotene - genetics; Biological and medical sciences; Biosynthesis; Biotechnology; Carotenoids; Cloning; DNA, Complementary; Economics; Enzymes; Feeds; Flowers; Flowers & plants; Food chains; Fruits; Fundamental and applied biological sciences. Psychology; Genetic engineering; Genetic technics; ketocarotenoids; metabolic engineering; Metabolism; Methods. Procedures. Technologies; Nicotiana - genetics; Nicotiana tabacum; Oxygenases - genetics; Peptides; Pigmentation; Plants, Genetically Modified; Plants, Toxic; Salmon; Tobacco; Tomatoes; Transgenic animals and transgenic plants; Transgenic plants; Xanthophylls; Flower; Targeting; Enzyme; Nectary; Stimulant plant; Gene expression; Nicotiana tabacum; Dicotyledones; Angiospermae; Chromoplast; Pigments; Spermatophyta; Transgenic plant; Solanaceae; Carotenoid; Hybrid gene
• ISSN: 1087-0156; 1546-1696
• DOI: 10.1038/78515

Using metabolic engineering, we have modified the carotenoid biosynthesis pathway in tobacco (Nicotiana tabacum) to produce astaxanthin, a red pigment of considerable economic value. To alter the carotenoid pathway in chromoplasts of higher plants, the cDNA of the gene CrtO from the alga Haematococcus pluvialis, encoding beta-carotene ketolase, was transferred to tobacco under the regulation of the tomato Pds (phytoene desaturase) promoter. The transit peptide of PDS from tomato was used to target the CRTO polypeptide to the plastids. Chromoplasts in the nectary tissue of transgenic plants accumulated (3S,3'S) astaxanthin and other ketocarotenoids, changing the color of the nectary from yellow to red. This accomplishment demonstrates that plants can be used as a source of novel carotenoid pigments such as astaxanthin. The procedures described in this work can serve as a platform technology for future genetic manipulations of pigmentation of fruits and flowers of horticultural and floricultural importance.