Ultra‐centrifugation force in adaptive evolution changes the cell structure of oleaginous yeast Trichosporon cutaneum into a favorable space for lipid accumulation

• Published in: Biotechnology and bioengineering 2022-06, Vol.119 (6), p.1509-1521
• Main Authors: Liu, Qi, Lu, Minping, Jin, Ci, Hou, Weiliang, Zhao, Liao, Bao, Jie
• Format: Article
• Language: English
• Subjects: Accumulation; adaptive evolution; Aviation fuel; Basidiomycota; Biodiesel fuels; Biofuels; Biomass; Cell density; Cell morphology; Cell size; cell structure; Cell walls; Centrifugation; Crop production; Cytology; Evolution; Evolution & development; Fractionation; Genomes; Industrial applications; Intracellular; Lignocellulose; Lipids; microbial lipid; Microorganisms; Mutation; Nutrition; oleaginous yeast; Sugar; Trichosporon - genetics; Trichosporon cutaneum; ultra‐centrifugation; Yeast; Yeasts
• ISSN: 0006-3592; 1097-0290
• DOI: 10.1002/bit.28060

Microbial lipid production from lignocellulose biomass provides an essential option for sustainable and carbon‐neutral supply of future aviation fuels, biodiesel, as well as various food and nutrition products. Oleaginous yeast is the major microbial cell factory but its lipid‐producing performance is far below the requirements of industrial application. Here we show an ultra‐centrifugation fractionation in adaptive evolution (UCF) of Trichosporon cutaneum based on the minor cell density difference. The lightest cells with the maximum intracellular lipid content were isolated by ultra‐centrifugation fractionation in the long‐term adaptive evolution. Significant changes occurred in the cell morphology with a fragile cell wall wrapping and enlarged intracellular space (two orders of magnitude increase in cell size). Complete and coordinate assimilations of all nonglucose sugars derived from lignocellulose were triggered and fluxed into lipid synthesis. Genome mutations and significant transcriptional regulations of the genes responsible for cell structure were identified and experimentally confirmed. The obtained T. cutaneum MP11 cells achieved a high lipid production of wheat straw, approximately five‐fold greater than that of the parental cells. The study provided an effective method for screening the high lipid‐containing oleaginous yeast cells as well as the intracellular products accumulating cells in general. An ultra‐centrifugation fractionation in adaptive evolution method was designed and experimentally verified for mutation and screen of very high microbial lipid producing cell factories of oleaginous yeast Trichosporon cutaneum. A highly favorable cell structure was created with extra‐larger cell volume and extra‐thinner membrane for lipid accumulation. The microbial lipid production from lignocellulose feedstock increased by five folds than that of the parental cells. The method could work for mutation and screening of the intracellular products producing cells in general.