Engineering oleaginous yeast Rhodotorula toruloides for overproduction of fatty acid ethyl esters
Abstract Background Production of biofuels and green chemicals by microbes is currently of great interest due to the increasingly limited reserves of fossil fuels. Biodiesel, especially fatty acid ethyl esters (FAEEs), is considered as an attractive alternative because of its similarity with petrodi...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
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BMC
2021-05-01
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| Series: | Biotechnology for Biofuels |
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| Online Access: | https://doi.org/10.1186/s13068-021-01965-3 |
| _version_ | 1818208788143931392 |
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| author | Yang Zhang Jie Peng Huimin Zhao Shuobo Shi |
| author_facet | Yang Zhang Jie Peng Huimin Zhao Shuobo Shi |
| author_sort | Yang Zhang |
| collection | DOAJ |
| description | Abstract Background Production of biofuels and green chemicals by microbes is currently of great interest due to the increasingly limited reserves of fossil fuels. Biodiesel, especially fatty acid ethyl esters (FAEEs), is considered as an attractive alternative because of its similarity with petrodiesel and compatibility with existing infrastructures. Cost-efficient bio-production of FAEEs requires a highly lipogenic production host that is suitable for large-scale fermentation. As a non-model oleaginous yeast that can be cultured to an extremely high cell density and accumulate over 70% cell mass as lipids, Rhodotorula toruloides represents an attractive host for FAEEs production. Results We first constructed the FAEE biosynthetic pathways in R. toruloides by introducing various wax ester synthase genes from different sources, and the bifunctional wax ester synthase/acyl-CoA-diacyglycerol acyltransferase (WS/DGAT) gene from Acinetobacter baylyi was successfully expressed, leading to a production of 826 mg/L FAEEs through shake-flask cultivation. We then mutated this bifunctional enzyme to abolish the DGAT activity, and further improved the titer to 1.02 g/L. Finally, to elevate the performance of Δku70-AbWS* in a bioreactor, both batch and fed-batch cultivation strategies were performed. The FAEEs titer, productivity and yield were 4.03 g/L, 69.5 mg/L/h and 57.9 mg/g (mg FAEEs/g glucose) under batch cultivation, and 9.97 g/L, 90.6 mg/L/h, and 86.1 mg/g under fed-batch cultivation. It is worth mentioning that most of the produced FAEEs were secreted out of the cell, which should greatly reduce the cost of downstream processing. Conclusion We achieved the highest FAEEs production in yeast with a final titer of 9.97 g/L and demonstrated that the engineered R. toruloides has the potential to serve as a platform strain for efficient production of fatty acid-derived molecules. |
| first_indexed | 2024-12-12T04:50:23Z |
| format | Article |
| id | doaj.art-f2fa04955df6420b980fdcf7b122c3fc |
| institution | Directory Open Access Journal |
| issn | 1754-6834 |
| language | English |
| last_indexed | 2024-12-12T04:50:23Z |
| publishDate | 2021-05-01 |
| publisher | BMC |
| record_format | Article |
| series | Biotechnology for Biofuels |
| spelling | doaj.art-f2fa04955df6420b980fdcf7b122c3fc2022-12-22T00:37:31ZengBMCBiotechnology for Biofuels1754-68342021-05-0114111110.1186/s13068-021-01965-3Engineering oleaginous yeast Rhodotorula toruloides for overproduction of fatty acid ethyl estersYang Zhang0Jie Peng1Huimin Zhao2Shuobo Shi3Beijing Advanced Innovation Center for Soft Matter Science and Engineering, College of Life Science and Technology, Beijing University of Chemical TechnologyBeijing Advanced Innovation Center for Soft Matter Science and Engineering, College of Life Science and Technology, Beijing University of Chemical TechnologyDepartment of Chemical and Biomolecular Engineering, University of Illinois At Urbana-ChampaignBeijing Advanced Innovation Center for Soft Matter Science and Engineering, College of Life Science and Technology, Beijing University of Chemical TechnologyAbstract Background Production of biofuels and green chemicals by microbes is currently of great interest due to the increasingly limited reserves of fossil fuels. Biodiesel, especially fatty acid ethyl esters (FAEEs), is considered as an attractive alternative because of its similarity with petrodiesel and compatibility with existing infrastructures. Cost-efficient bio-production of FAEEs requires a highly lipogenic production host that is suitable for large-scale fermentation. As a non-model oleaginous yeast that can be cultured to an extremely high cell density and accumulate over 70% cell mass as lipids, Rhodotorula toruloides represents an attractive host for FAEEs production. Results We first constructed the FAEE biosynthetic pathways in R. toruloides by introducing various wax ester synthase genes from different sources, and the bifunctional wax ester synthase/acyl-CoA-diacyglycerol acyltransferase (WS/DGAT) gene from Acinetobacter baylyi was successfully expressed, leading to a production of 826 mg/L FAEEs through shake-flask cultivation. We then mutated this bifunctional enzyme to abolish the DGAT activity, and further improved the titer to 1.02 g/L. Finally, to elevate the performance of Δku70-AbWS* in a bioreactor, both batch and fed-batch cultivation strategies were performed. The FAEEs titer, productivity and yield were 4.03 g/L, 69.5 mg/L/h and 57.9 mg/g (mg FAEEs/g glucose) under batch cultivation, and 9.97 g/L, 90.6 mg/L/h, and 86.1 mg/g under fed-batch cultivation. It is worth mentioning that most of the produced FAEEs were secreted out of the cell, which should greatly reduce the cost of downstream processing. Conclusion We achieved the highest FAEEs production in yeast with a final titer of 9.97 g/L and demonstrated that the engineered R. toruloides has the potential to serve as a platform strain for efficient production of fatty acid-derived molecules.https://doi.org/10.1186/s13068-021-01965-3Fatty acid ethyl estersWax ester synthaseR. toruloidesEnzyme engineeringBiodieselMetabolic engineering |
| spellingShingle | Yang Zhang Jie Peng Huimin Zhao Shuobo Shi Engineering oleaginous yeast Rhodotorula toruloides for overproduction of fatty acid ethyl esters Biotechnology for Biofuels Fatty acid ethyl esters Wax ester synthase R. toruloides Enzyme engineering Biodiesel Metabolic engineering |
| title | Engineering oleaginous yeast Rhodotorula toruloides for overproduction of fatty acid ethyl esters |
| title_full | Engineering oleaginous yeast Rhodotorula toruloides for overproduction of fatty acid ethyl esters |
| title_fullStr | Engineering oleaginous yeast Rhodotorula toruloides for overproduction of fatty acid ethyl esters |
| title_full_unstemmed | Engineering oleaginous yeast Rhodotorula toruloides for overproduction of fatty acid ethyl esters |
| title_short | Engineering oleaginous yeast Rhodotorula toruloides for overproduction of fatty acid ethyl esters |
| title_sort | engineering oleaginous yeast rhodotorula toruloides for overproduction of fatty acid ethyl esters |
| topic | Fatty acid ethyl esters Wax ester synthase R. toruloides Enzyme engineering Biodiesel Metabolic engineering |
| url | https://doi.org/10.1186/s13068-021-01965-3 |
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