ArticleProceedings of the National Academy of Sciences of the United States of America2014
Novel carotenoid cleavage dioxygenase catalyzes the first dedicated step in saffron crocin biosynthesis.
Article in Proceedings of the National Academy of Sciences of the United States of America, 2014. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 124 papers.
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124 citing papers in PubMed, 289 citations in OpenAlex.
- Bioconversion of carotenoids into high-value crocins using a marine sponge carotenoid cleavage dioxygenase.The New phytologist · 2026Article
- The carotenoids metabolism during tomato fruit ripening: insights into multi-level regulatory network.BMC plant biology · 2026Review
- An evolutionarily diverged CCD4 enzyme negatively regulates mesocotyl elongation in rice.The New phytologist · 2026Article
- Regulation of apocarotenoids for quality improvement and biofortification of horticultural crops.Journal of advanced research · 2026Review
- Genome-Wide Analysis of TomatoPlants (Basel, Switzerland) · 2026Article
- Evolutionary adaptation of CCD4 enzymes inFrontiers in plant science · 2026Article
- Superior haplotypes of genes associated with higher grain yield under reproductive stage drought stress in rice.Journal of experimental botany · 2025Article
- Novel plant cell suspension platforms for saffron apocarotenoid production and its impact on carotenoid and volatile profiles.Plant biotechnology journal · 2025Article
- Integrative Analyses of Metabolome and Transcriptome Reveals Apocarotenoid and Flavonoid Biosynthesis During Saffron (Food science & nutrition · 2025Article
- Genome-wide identification of CCD gene family in Peach (Prunus persica L. Batsch) and expression analysis with aroma norisoprenoids.BMC plant biology · 2025Article
- Natural CCD2 Variants and RNA Interference for Boosting Crocin Biosynthesis in Tomato.Biology · 2025Article
- CsCCD2L is Involved in the Response to Light Stress by Regulating Zeaxanthin Content in Saffron (Crocus sativus L.).Plant foods for human nutrition (Dordrecht, Netherlands) · 2025Article
- Montbretia flowers as a source of bioactive crocins: Biotechnology tools and delivery systems.Biotechnology reports (Amsterdam, Netherlands) · 2025Article
- Temporal gene expression profiling suggests stage-specific regulation of apocarotenoid biosynthesis genes during stigma development inPhysiology and molecular biology of plants : an international journal of functional plant biology · 2025Article
- Saponins, the Unexplored Secondary Metabolites in Plant Defense: Opportunities in Integrated Pest Management.Plants (Basel, Switzerland) · 2025Review
- Water-soluble carotenoid: focused on natural carotenoid crocin.Food science and biotechnology · 2025Review
- Metabolic engineering of Yarrowia lipolytica for the production and secretion of the saffron ingredient crocetin.Biotechnology for biofuels and bioproducts · 2025Article
- β-cyclocitral as a cross-species mediator of abiotic stress signaling: insights and future directions toward crop improvement.Frontiers in plant science · 2025Review
- Biotechnological production of crocetin and crocins using a carotenoid cleavage dioxygenase (CCD4) fromFrontiers in plant science · 2025Article
- Potential therapeutic effects of crocin.Naunyn-Schmiedeberg's archives of pharmacology · 2024Review
64 more citing papers are in PubMed but not listed here.
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Authors and funding
11 authors at 4 institutions in 4 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Crocus sativus stigmas are the source of the saffron spice and accumulate the apocarotenoids crocetin, crocins, picrocrocin, and safranal, responsible for its color, taste, and aroma. Through deep transcriptome sequencing, we identified a novel dioxygenase, carotenoid cleavage dioxygenase 2 (CCD2), expressed early during stigma development and closely related to, but distinct from, the CCD1 dioxygenase family. CCD2 is the only identified member of a novel CCD clade, presents the structural features of a bona fide CCD, and is able to cleave zeaxanthin, the presumed precursor of saffron apocarotenoids, both in Escherichia coli and in maize endosperm. The cleavage products, identified through high-resolution mass spectrometry and comigration with authentic standards, are crocetin dialdehyde and crocetin, respectively. In vitro assays show that CCD2 cleaves sequentially the 7,8 and 7',8' double bonds adjacent to a 3-OH-β-ionone ring and that the conversion of zeaxanthin to crocetin dialdehyde proceeds via the C30 intermediate 3-OH-β-apo-8'-carotenal. In contrast, zeaxanthin cleavage dioxygenase (ZCD), an enzyme previously claimed to mediate crocetin formation, did not cleave zeaxanthin or 3-OH-β-apo-8'-carotenal in the test systems used. Sequence comparison and structure prediction suggest that ZCD is an N-truncated CCD4 form, lacking one blade of the β-propeller structure conserved in all CCDs. These results constitute strong evidence that CCD2 catalyzes the first dedicated step in crocin biosynthesis. Similar to CCD1, CCD2 has a cytoplasmic localization, suggesting that it may cleave carotenoids localized in the chromoplast outer envelope.
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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.