title: Differential carotenoid production and gene expression in Xanthophyllomyces dendrorhous grown in a nonfermentable carbon source.
abstract: Xanthophyllomyces dendrorhous is a basidiomycetous yeast of considerable biotechnological interest because it synthesizes astaxanthin as its main carotenoid. The carotenoid production increases when it is grown using nonfermentable compounds as the sole carbon source. This work analyzes the expression of the carotenogenic genes and their relationship with the amount and types of carotenoids produced when X. dendrorhous is grown using a nonfermentable (succinate) or a fermentable carbon source (glucose). When X. dendrorhous is grown in succinate, carotenoid production is approximately three times higher than when it is grown in glucose. Moreover, carotenoid biosynthesis occurs at the start of the growth cycle when X. dendrorhous is grown in succinate, whereas when it is grown in glucose, carotenoids are produced at the end of the exponential phase. Additionally, we observed that some carotenogenic genes, such as alternative transcripts of crtYB and crtI, are differentially expressed when the yeast is grown in these carbon sources; other genes, such as crtS, exhibit a similar pattern of expression. Our data indicate that transcriptional regulation is not sufficient to explain the differences in carotenoid production between the two culture conditions, indicating that additional regulatory mechanisms may be operating in the carotenogenic pathway of X. dendrorhous.
authors.affiliation: Centro de Biotecnología y Departamento de Ciencias Ecológicas, Facultad de Ciencias, Universidad de Chile, Santiago, Chile.
authors.forename: Aniela
authors.initials: A
authors.lastname: Wozniak
authors.forename: Carla
authors.initials: C
authors.lastname: Lozano
authors.forename: Salvador
authors.initials: S
authors.lastname: Barahona
authors.forename: Mauricio
authors.initials: M
authors.lastname: Niklitschek
authors.forename: Andrés
authors.initials: A
authors.lastname: Marcoleta
authors.forename: Jennifer
authors.initials: J
authors.lastname: Alcaíno
authors.forename: Dionisia
authors.initials: D
authors.lastname: Sepulveda
authors.forename: Marcelo
authors.initials: M
authors.lastname: Baeza
authors.forename: Víctor
authors.initials: V
authors.lastname: Cifuentes
mesh_terms: D017398:Alternative Splicing / Q000235:genetics; D001487:Basidiomycota / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D002338:Carotenoids / Q000096:biosynthesis* / Q000235:genetics / Q000378:metabolism; D000431:Ethanol / Q000378:metabolism; D015966:Gene Expression Regulation, Fungal; D005800:Genes, Fungal / Q000235:genetics; D005947:Glucose / Q000378:metabolism*; D011401:Promoter Regions, Genetic / Q000235:genetics; D012331:RNA, Fungal / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics; D019802:Succinic Acid / Q000378:metabolism*; D024341:Xanthophylls / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism
chemical_list: D012331:RNA, Fungal; D012333:RNA, Messenger; D024341:Xanthophylls; D002338:Carotenoids; D000431:Ethanol; C005948:astaxanthine; D019802:Succinic Acid; D005947:Glucose