title: Efficient production of lycopene in Saccharomyces cerevisiae by expression of synthetic crt genes from a plasmid harboring the ADH2 promoter.
abstract: Lycopene is an effective antioxidant proposed as a possible treatment for some cancers and other degenerative human conditions. This study aims at generation of a yeast strain (Saccharomyces cerevisiae) of efficient productivity of lycopene by overexpressing synthetic genes derived from crtE, crtB and crtI genes of Erwinia uredovora. These synthetic genes were constructed in accordance with the preferred codon usage in S. cerevisiae but with no changes in amino acid sequences of the gene products. S. cerevisiae cells were transformed with these synthetic crt genes, whose expression was regulated by the ADH2 promoter, which is de-repressed upon glucose depletion. The RT-PCR and Western blotting analyses indicated that the synthetic crt genes were efficiently transcribed and translated in crt-transformed S. cerevisiae cells. The highest level of lycopene in one of the transformed lines was 3.3mglycopene/g dry cell weight, which is higher than the previously reported levels of lycopene in other microorganisms transformed with the three genes. These results suggest the excellence of using the synthetic crt genes and the ADH2 promoter in generation of recombinant S. cerevisiae that produces a high level of lycopene. The level of ergosterol was reversely correlated to that of lycopene in crt-transformed S. cerevisiae cells, suggesting that two pathways for lycopene and ergosterol syntheses compete for the use of farnesyl diphosphate.
authors.affiliation: Department of Biological Sciences, Faculty of Science, King Abdulaziz University (KAU), P.O. Box 80141, Jeddah 21589, Saudi Arabia; Department of Genetics, Faculty of Agriculture, Ain Shams University, Cairo, Egypt. Electronic address: bahieldin55@gmail.com.
authors.forename: Ahmed
authors.initials: A
authors.lastname: Bahieldin
authors.affiliation: Department of Biological Sciences, Faculty of Science, King Abdulaziz University (KAU), P.O. Box 80141, Jeddah 21589, Saudi Arabia; Genetics and Cytology Department, Genetic Engineering and Biotechnology Division, National Research Center, Dokki, Egypt.
authors.forename: Nour O
authors.initials: NO
authors.lastname: Gadalla
authors.affiliation: Department of Biological Sciences, Faculty of Science, King Abdulaziz University (KAU), P.O. Box 80141, Jeddah 21589, Saudi Arabia.
authors.forename: Saleh M
authors.initials: SM
authors.lastname: Al-Garni
authors.affiliation: Department of Biological Sciences, Faculty of Science, King Abdulaziz University (KAU), P.O. Box 80141, Jeddah 21589, Saudi Arabia.
authors.forename: Hussein
authors.initials: H
authors.lastname: Almehdar
authors.affiliation: Department of Biological Sciences, Faculty of Science, King Abdulaziz University (KAU), P.O. Box 80141, Jeddah 21589, Saudi Arabia.
authors.forename: Samah
authors.initials: S
authors.lastname: Noor
authors.affiliation: Department of Biological Sciences, Faculty of Science, King Abdulaziz University (KAU), P.O. Box 80141, Jeddah 21589, Saudi Arabia; Department of Genetics, Faculty of Agriculture, Ain Shams University, Cairo, Egypt.
authors.forename: Sabah M
authors.initials: SM
authors.lastname: Hassan
authors.affiliation: Department of Biological Sciences, Faculty of Science, King Abdulaziz University (KAU), P.O. Box 80141, Jeddah 21589, Saudi Arabia; Agricultural Genetic Engineering Research Institute (AGERI), Agriculture Research Center (ARC), Giza, Egypt.
authors.forename: Ahmed M
authors.initials: AM
authors.lastname: Shokry
authors.affiliation: Department of Biological Sciences, Faculty of Science, King Abdulaziz University (KAU), P.O. Box 80141, Jeddah 21589, Saudi Arabia.
authors.forename: Jamal S M
authors.initials: JS
authors.lastname: Sabir
authors.affiliation: National Institute for Basic Biology, Myodaiji, Okazaki, Aichi 444-8585, Japan.
authors.forename: Norio
authors.initials: N
authors.lastname: Murata
mesh_terms: D002338:Carotenoids / Q000096:biosynthesis*; D003001:Cloning, Molecular; D004875:Ergosterol / Q000096:biosynthesis; D004885:Erwinia / Q000201:enzymology / Q000235:genetics; D051231:Farnesyltranstransferase / Q000096:biosynthesis / Q000235:genetics*; D015870:Gene Expression; D005798:Genes, Bacterial; D051232:Geranylgeranyl-Diphosphate Geranylgeranyltransferase / Q000096:biosynthesis / Q000235:genetics*; D000077276:Lycopene; D030781:Organisms, Genetically Modified / Q000235:genetics / Q000378:metabolism; D010088:Oxidoreductases / Q000096:biosynthesis / Q000235:genetics*; D010957:Plasmids; D011401:Promoter Regions, Genetic; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D014170:Transformation, Genetic
chemical_list: D002338:Carotenoids; D010088:Oxidoreductases; C022398:phytoene dehydrogenase; D051231:Farnesyltranstransferase; D051232:Geranylgeranyl-Diphosphate Geranylgeranyltransferase; D000077276:Lycopene; D004875:Ergosterol
keywords: ADH2 promoter; Ergosterol; Lycopene; Saccharomyces cerevisiae; Vector dualsystem; crt gene