title: Highly efficient biosynthesis of astaxanthin in Saccharomyces cerevisiae by integration and tuning of algal crtZ and bkt.
abstract: Astaxanthin is a highly valued carotenoid with strong antioxidant activity and has wide applications in aquaculture, food, cosmetic, and pharmaceutical industries. The market demand for natural astaxanthin promotes research in metabolic engineering of heterologous hosts for astaxanthin production. In this study, an astaxanthin-producing Saccharomyces cerevisiae strain was created by successively introducing the Haematococcus pluvialis β-carotenoid hydroxylase (crtZ) and ketolase (bkt) genes into a previously constructed β-carotene hyperproducer. Further integration of strategies including codon optimization, gene copy number adjustment, and iron cofactor supplementation led to significant increase in the astaxanthin production, reaching up to 4.7 mg/g DCW in the shake-flask cultures which is the highest astaxanthin content in S. cerevisiae reported to date. Besides, the substrate specificity of H. pluvialis CrtZ and BKT and the probable formation route of astaxanthin from β-carotene in S. cerevisiae were figured out by expressing the genes separately and in combination. The yeast strains engineered in this work provide a basis for further improving biotechnological production of astaxanthin and might offer a useful general approach to the construction of heterologous biosynthetic pathways for other natural products.
authors.affiliation: Institute of Bioengineering, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, People's Republic of China.
authors.forename: Pingping
authors.initials: P
authors.lastname: Zhou
authors.affiliation: Institute of Bioengineering, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, People's Republic of China.|Key Laboratory of Biomass Chemical Engineering of Ministry of Education, Zhejiang University, Hangzhou, 310027, People's Republic of China.
authors.forename: Lidan
authors.initials: L
authors.lastname: Ye
authors.affiliation: Institute of Bioengineering, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, People's Republic of China.
authors.forename: Wenping
authors.initials: W
authors.lastname: Xie
authors.affiliation: Institute of Bioengineering, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, People's Republic of China.
authors.forename: Xiaomei
authors.initials: X
authors.lastname: Lv
authors.affiliation: Institute of Bioengineering, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, People's Republic of China. yuhongwei@zju.edu.cn.
authors.forename: Hongwei
authors.initials: H
authors.lastname: Yu
mesh_terms: D020418:Algal Proteins / Q000235:genetics / Q000378:metabolism*; D053898:Biosynthetic Pathways; D060847:Metabolic Engineering / Q000379:methods*; D006899:Mixed Function Oxygenases / Q000235:genetics / Q000378:metabolism; D010105:Oxygenases / Q000235:genetics / Q000378:metabolism; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000378:metabolism*; D016823:Volvocida / Q000201:enzymology* / Q000235:genetics; D024341:Xanthophylls / Q000096:biosynthesis
chemical_list: D020418:Algal Proteins; D011994:Recombinant Proteins; D024341:Xanthophylls; C005948:astaxanthine; D006899:Mixed Function Oxygenases; D010105:Oxygenases; C093259:beta-carotene ketolase; C079232:beta-carotene hydroxylase
keywords: Astaxanthin; Haematococcus pluvialis; Metabolic engineering; Saccharomyces cerevisiae; β-Carotenoid hydroxylase; β-Carotenoid ketolase