title: High lipid accumulation in Yarrowia lipolytica cultivated under double limitation of nitrogen and magnesium.
abstract: Yarrowia lipolytica cultivated under double nitrogen and magnesium limitation, but not under single nitrogen or single magnesium limitation, produced 12.2g/l biomass containing 47.5% lipids, which corresponds to a lipid production 5.8g/l. These yields are the higher described in the literature for wild strains of Y. lipolytica. Transcription of ACL1 and ACL2, encoding for ATP-citrate lyase (ATP:CL) was observed even under non-oleaginous conditions but high activity of ATP:CL was only detected under oleaginous conditions induced by low or zero activity of NAD(+) dependent isocitrate dehydrogenase. The low activity of malic enzyme (ME), a NADPH donor in typical oleaginous microorganisms, indicated that ME may not be implicated in lipid biosynthesis in this yeast, and NADPH may be provided by the pentose phosphate pathway (PPP). These findings underline the essential role of magnesium in lipogenesis, which is currently quite unexplored. The presence of organic nitrogen in low concentrations during lipogenesis was also required, and this peculiarity was probably related with the PPP functioning, being the NADPH donor of lipogenic machinery in Y. lipolytica.
authors: Unit of Microbiology, Division of Genetics, Cell and Development Biology, Department of Biology, University of Patras, Patras 26504, Greece.
authors: S
authors: S
authors: Bellou
authors: Unit of Microbiology, Division of Genetics, Cell and Development Biology, Department of Biology, University of Patras, Patras 26504, Greece.
authors: I-E
authors: IE
authors: Triantaphyllidou
authors: Unit of Microbiology, Division of Genetics, Cell and Development Biology, Department of Biology, University of Patras, Patras 26504, Greece.
authors: P
authors: P
authors: Mizerakis
authors: Unit of Microbiology, Division of Genetics, Cell and Development Biology, Department of Biology, University of Patras, Patras 26504, Greece. Electronic address: George.Aggelis@upatras.gr.
authors: G
authors: G
authors: Aggelis
mesh_terms: D001275:ATP Citrate (pro-S)-Lyase / Q000378:metabolism; D018533:Biomass; D019149:Bioreactors; D019343:Citric Acid / Q000378:metabolism; D004789:Enzyme Activation; D007521:Isocitrate Dehydrogenase / Q000378:metabolism; D050356:Lipid Metabolism; D008055:Lipids / Q000096:biosynthesis / Q000737:chemistry*; D008274:Magnesium / Q000737:chemistry / Q000378:metabolism*; D009584:Nitrogen / Q000737:chemistry / Q000378:metabolism*; D010084:Oxidation-Reduction; D010427:Pentose Phosphate Pathway; D025062:Yarrowia / Q000235:genetics / Q000378:metabolism*
chemical_list: D008055:Lipids; D019343:Citric Acid; D007521:Isocitrate Dehydrogenase; D001275:ATP Citrate (pro-S)-Lyase; D008274:Magnesium; D009584:Nitrogen
keywords: Double limitation; Magnesium limitation; Nitrogen limitation; Organic nitrogen; Yarrowia lipolytica