title: Expression of Xanthophyllomyces dendrorhous cytochrome-P450 hydroxylase and reductase in Mucor circinelloides.
abstract: Carotenoids are natural pigments that act as powerful antioxidants and have various beneficial effects on human and animal health. Mucor circinelloides (Mucoromycotina) is a carotenoid producing zygomycetes fungus, which accumulates β-carotene as the main carotenoid but also able to produce the hydroxylated derivatives of β-carotene (i.e. zeaxanthin and β-cryptoxanthin) in low amount. These xanthophylls, together with the ketolated derivatives of β-carotene (such as canthaxanthin, echinenone and astaxanthin) have better antioxidant activity than β-carotene. In this study our aim was to modify and enhance the xanthophyll production of the M. circinelloides by expression of heterologous genes responsible for the astaxanthin biosynthesis. The crtS and crtR genes, encoding the cytochrome-P450 hydroxylase and reductase, respectively, of wild-type and astaxanthin overproducing mutant Xanthophyllomyces dendrorhous strains were amplified from cDNA and the nucleotide and the deduced amino acid sequences were compared to each other. Introduction of the crtS on autonomously replicating plasmid in the wild-type M. circinelloides resulted enhanced zeaxanthin and β-cryptoxanthin accumulation and the presence of canthaxanthin, echinenone and astaxanthin in low amount; the β-carotene hydroxylase and ketolase activity of the X. dendrorhous cytochrome-P450 hydroxylase in M. circinelloides was verified. Increased canthaxanthin and echinenone production was observed by expression of the gene in a canthaxanthin producing mutant M. circinelloides. Co-expression of the crtR and crtS genes led to increase in the total carotenoid and slight change in xanthophyll accumulation in comparison with transformants harbouring the single crtS gene.
authors.affiliation: Department of Microbiology, Faculty of Science and Informatics, University of Szeged, Közép fasor 52., Szeged, 6726, Hungary, csernetics.arpad@gmail.com.
authors.forename: Árpád
authors.initials: Á
authors.lastname: Csernetics
authors.forename: Eszter
authors.initials: E
authors.lastname: Tóth
authors.forename: Anita
authors.initials: A
authors.lastname: Farkas
authors.forename: Gábor
authors.initials: G
authors.lastname: Nagy
authors.forename: Ottó
authors.initials: O
authors.lastname: Bencsik
authors.forename: Csaba
authors.initials: C
authors.lastname: Vágvölgyi
authors.forename: Tamás
authors.initials: T
authors.lastname: Papp
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D003001:Cloning, Molecular; D003577:Cytochrome P-450 Enzyme System / Q000235:genetics* / Q000378:metabolism; D009089:Mucor / Q000145:classification / Q000201:enzymology* / Q000235:genetics; D009154:Mutation; D009251:NADPH-Ferrihemoprotein Reductase / Q000235:genetics* / Q000378:metabolism; D010957:Plasmids / Q000235:genetics / Q000378:metabolism; D017422:Sequence Analysis, DNA; D014169:Transformation, Bacterial; D024341:Xanthophylls / Q000096:biosynthesis*; D019207:beta Carotene / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D024341:Xanthophylls; D019207:beta Carotene; D003577:Cytochrome P-450 Enzyme System; D009251:NADPH-Ferrihemoprotein Reductase