Loading patent…
AssigneeBall Horticultural Company
InventorsRandal Hauptmann, Robert Eisenreich, William Eschenfeldt, Zubin Khambatta
Estimating the term…
The formation of a carotenoid compound containing a 4-keto-β-ionene ring such as astaxanthin or canthaxanthin in flowers, and particularly in the corolla and reproductive parts of a flower of a higher plant whose flowers produce a carotenoid compound containing a β-ionene ring such as β-carotene or zeaxanthin, but otherwise do not produce astaxanthin or canthaxanthin is disclosed. One or more genes controlled by a promoter are inserted (transformed) into a higher plant. The inserted gene encodes a chimeric enzyme including (a) a carotenoid-forming enzyme that is at least a ketolase. That gene is operatively linked to (b) a plastid-directed transit peptide. Some higher plants to be transformed produce at least zeaxanthin or β-carotene in their flowers prior to transformation, whereas other plants produce little if any colored carotenoid pigments prior to transformation and are transformed with a cassette of carotenoids-forming genes. Methods of transformation and use of the transformed plants are described.
A transgenic plant or a regenerable portion thereof whose genome contains a transgene that encodes a chimeric ketolase enzyme polypeptide having two portions, (i) an N-terminal first portion comprising a plastid transit peptide portion fused to (ii) a second ketolase enzyme portion that converts a carotenoid β-ionene ring into a 4-keto-β-ionene ring, said trangene being operatively linked to a promoter that controls expression of said transgene, wherein the flower petals of a plant of the same type that is not transformed with said chimeric ketolase produce a carotenoid compound that contains a β-ionene ring having an unsubstituted 4-position, and wherein the flower petals of said transgenic plant accumulate a carotenoid compound having a 4-keto-β-ionene ring.
A transgenic plant or a regenerable portion thereof whose genome contains a transgene that encodes a chimeric ketolase enzyme polypeptide having two portions, (i) an N-terminal first portion comprising a plastid transit peptide fused to (ii) a second ketolase enzyme portion that converts a carotenoid β-ionene ring into a 4-keto-β-ionene ring, said transgene being operatively linked to a promoter that controls expression of said transgene, wherein the flower petals of a plant of the same type that is not transformed with said chimeric ketolase produce one or both of β-carotene and zeaxanthin, and wherein the flower petals of said transgenic plant accumulate a carotenoid compound having a 4-keto-β-ionene ring.
A transgenic plant or a regenerable portion thereof whose genome contains a transgene that encodes a chimeric ketolase enzyme polypeptide having two portions, (i) an N-terminal first portion comprising a plastid transit peptide fused to (ii) a second ketolase enzyme portion that converts a carotenoid β-ionene ring into a 4-keto-β-ionene ring, said transgene being operatively linked to a petal-preferred promoter that controls expression of said transgene and is from a species different from that of said plastid transit peptide, wherein the flower petals of a plant of the same type that is not transformed with said chimeric ketolase produce one or both of β-carotene and zeaxanthin, and wherein the flower petals of said transgenic plant accumulate a carotenoid compound having a 4-keto-β-ionene ring.
Dependencies are inferred from the claim text.