title: Simultaneous degradation of phytic acid and starch by an industrial strain of Saccharomyces cerevisiae producing phytase and alpha-amylase.
abstract: Phytase liberates inorganic phosphate from phytic acid (myo-inositol hexakisphosphate) which is the major phosphate reserve in plant-derived foods and feeds. An industrial strain of Saccharomyces cerevisiae expressing the Debaryomyces castellii phytase gene (phytDc) and D. occidentalis alpha-amylase gene (AMY) was developed. The phytDc and AMY genes were constitutively expressed under the ADC1 promoter in S. cerevisiae by using the delta-integration system, which contains DNA derived exclusively from yeast. The recombinant industrial strain secreted both phytase and alpha-amylase for the efficient degradation of phytic acid and starch as main components of plant seeds. This new strain hydrolyzed 90% of 0.5% (w/v) sodium phytate within 5 days of growth and utilized 100% of 2% (w/v) starch within 48 h simultaneously.
authors.affiliation: Department of Biological Sciences, College of Natural Sciences, Chonnam National University, Gwangju 500-757, South Korea.
authors.forename: Mi-Hyeon
authors.initials: MH
authors.lastname: Lim
authors.forename: Ok-Hee
authors.initials: OH
authors.lastname: Lee
authors.forename: Jong-Eon
authors.initials: JE
authors.lastname: Chin
authors.forename: Hyun-Mi
authors.initials: HM
authors.lastname: Ko
authors.forename: Il-Chul
authors.initials: IC
authors.lastname: Kim
authors.forename: Hwanghee Blaise
authors.initials: HB
authors.lastname: Lee
authors.forename: Suhn-Young
authors.initials: SY
authors.lastname: Im
authors.forename: Suk
authors.initials: S
authors.lastname: Bai
mesh_terms: D010832:6-Phytase / Q000235:genetics / Q000378:metabolism*; D000821:Animal Feed; D000818:Animals; D005800:Genes, Fungal; D006801:Humans; D006868:Hydrolysis; D010833:Phytic Acid / Q000378:metabolism*; D016133:Polymerase Chain Reaction; D011994:Recombinant Proteins / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000201:enzymology* / Q000235:genetics / Q000378:metabolism; D012639:Seeds; D013213:Starch / Q000378:metabolism*; D014170:Transformation, Genetic; D000516:alpha-Amylases / Q000235:genetics / Q000378:metabolism*
chemical_list: D011994:Recombinant Proteins; D010833:Phytic Acid; D013213:Starch; D010832:6-Phytase; D000516:alpha-Amylases