1
|
Hassane AMA, Eldiehy KSH, Saha D, Mohamed H, Mosa MA, Abouelela ME, Abo-Dahab NF, El-Shanawany ARA. Oleaginous fungi: a promising source of biofuels and nutraceuticals with enhanced lipid production strategies. Arch Microbiol 2024; 206:338. [PMID: 38955856 DOI: 10.1007/s00203-024-04054-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2024] [Revised: 06/13/2024] [Accepted: 06/14/2024] [Indexed: 07/04/2024]
Abstract
Oleaginous fungi have attracted a great deal of interest for their potency to accumulate high amounts of lipids (more than 20% of biomass dry weight) and polyunsaturated fatty acids (PUFAs), which have a variety of industrial and biological applications. Lipids of plant and animal origin are related to some restrictions and thus lead to attention towards oleaginous microorganisms as reliable substitute resources. Lipids are traditionally biosynthesized intra-cellularly and involved in the building structure of a variety of cellular compartments. In oleaginous fungi, under certain conditions of elevated carbon ratio and decreased nitrogen in the growth medium, a change in metabolic pathway occurred by switching the whole central carbon metabolism to fatty acid anabolism, which subsequently resulted in high lipid accumulation. The present review illustrates the bio-lipid structure, fatty acid classes and biosynthesis within oleaginous fungi with certain key enzymes, and the advantages of oleaginous fungi over other lipid bio-sources. Qualitative and quantitative techniques for detecting the lipid accumulation capability of oleaginous microbes including visual, and analytical (convenient and non-convenient) were debated. Factors affecting lipid production, and different approaches followed to enhance the lipid content in oleaginous yeasts and fungi, including optimization, utilization of cost-effective wastes, co-culturing, as well as metabolic and genetic engineering, were discussed. A better understanding of the oleaginous fungi regarding screening, detection, and maximization of lipid content using different strategies could help to discover new potent oleaginous isolates, exploit and recycle low-cost wastes, and improve the efficiency of bio-lipids cumulation with biotechnological significance.
Collapse
Affiliation(s)
- Abdallah M A Hassane
- Department of Botany and Microbiology, Faculty of Science, Al-Azhar University, P.O. Box 71524, Assiut, Egypt.
| | - Khalifa S H Eldiehy
- Department of Botany and Microbiology, Faculty of Science, Al-Azhar University, P.O. Box 71524, Assiut, Egypt
| | - Debanjan Saha
- Department of Molecular Biology and Biotechnology, Tezpur University, P.O. Box 784028, Assam, India
| | - Hassan Mohamed
- Department of Botany and Microbiology, Faculty of Science, Al-Azhar University, P.O. Box 71524, Assiut, Egypt
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, P.O. Box 255000, Zibo, China
| | - Mohamed A Mosa
- Nanotechnology and Advanced Nano-Materials Laboratory (NANML), Plant Pathology Research Institute, Agricultural Research Center, P.O. Box 12619, Giza, Egypt
| | - Mohamed E Abouelela
- Department of Pharmacognosy, Faculty of Pharmacy, Al-Azhar University, P.O. Box 11884, Cairo, Egypt
| | - Nageh F Abo-Dahab
- Department of Botany and Microbiology, Faculty of Science, Al-Azhar University, P.O. Box 71524, Assiut, Egypt
| | - Abdel-Rehim A El-Shanawany
- Department of Botany and Microbiology, Faculty of Science, Al-Azhar University, P.O. Box 71524, Assiut, Egypt
| |
Collapse
|
2
|
Jiang W, Peng H, He L, Lesma-Amaro R, Haritos VS. Exploring engineering strategies that enhance de novo production of exotic cyclopropane fatty acids in Saccharomyces cerevisiae. Biotechnol J 2024; 19:e2300694. [PMID: 38403410 DOI: 10.1002/biot.202300694] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2023] [Revised: 01/11/2024] [Accepted: 01/18/2024] [Indexed: 02/27/2024]
Abstract
Cycloalkanes have broad applications as specialty fuels, lubricants, and pharmaceuticals but are not currently available from renewable sources, whereas, production of microbial cycloalkanes such as cyclopropane fatty acids (CFA) has bottlenecks. Here, a systematic investigation was undertaken into the biosynthesis of CFA in Saccharomyces cerevisiae heterologously expressing bacterial CFA synthase. The enzyme catalyzes formation of a 3-membered ring in unsaturated fatty acids. Monounsaturated fatty acids in phospholipids (PL) are the site of CFA synthesis; precursor cis-Δ9 C16 and C18 fatty acids were enhanced through OLE1 and SAM2 overexpression which enhanced CFA in PL. CFA turnover from PL to storage in triacylglycerols (TAG) was achieved by phospholipase PBL2 overexpression and acyl-CoA synthase to increase flux to TAG. Consequently, CFA storage as TAG reached 12 mg g-1 DCW, improved 3-fold over the base strain and >22% of TAG was CFA. Our research improves understanding of cycloalkane biosynthesis in yeast and offers insights into processing of other exotic fatty acids.
Collapse
Affiliation(s)
- Wei Jiang
- Department of Chemical and Biological Engineering, Monash University, Clayton, Victoria, Australia
- Imperial College Centre for Synthetic Biology, Imperial College London, London, UK
- Department of Bioengineering, Imperial College London, London, UK
| | - Huadong Peng
- Imperial College Centre for Synthetic Biology, Imperial College London, London, UK
- Department of Bioengineering, Imperial College London, London, UK
| | - Lizhong He
- Department of Chemical and Biological Engineering, Monash University, Clayton, Victoria, Australia
| | - Rodrigo Lesma-Amaro
- Imperial College Centre for Synthetic Biology, Imperial College London, London, UK
- Department of Bioengineering, Imperial College London, London, UK
| | - Victoria S Haritos
- Department of Chemical and Biological Engineering, Monash University, Clayton, Victoria, Australia
| |
Collapse
|
3
|
Assessing the genomic composition, putative ecological relevance and biotechnological potential of plasmids from sponge bacterial symbionts. Microbiol Res 2022; 265:127183. [PMID: 36108440 DOI: 10.1016/j.micres.2022.127183] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Revised: 02/24/2022] [Accepted: 09/01/2022] [Indexed: 11/24/2022]
Abstract
Plasmid-mediated transfer of genes can have direct consequences in several biological processes within sponge microbial communities. However, very few studies have attempted genomic and functional characterization of plasmids from marine host-associated microbial communities in general and those of sponges in particular. In the present study, we used an endogenous plasmid isolation method to obtain plasmids from bacterial symbionts of the marine sponges Stylissa carteri and Paratetilla sp. and investigated the genomic composition, putative ecological relevance and biotechnological potential of these plasmids. In total, we isolated and characterized three complete plasmids, three plasmid prophages and one incomplete plasmid. Our results highlight the importance of plasmids to transfer relevant genetic traits putatively involved in microbial symbiont adaptation and host-microbe and microbe-microbe interactions. For example, putative genes involved in bacterial response to chemical stress, competition, metabolic versatility and mediation of bacterial colonization and pathogenicity were detected. Genes coding for enzymes and toxins of biotechnological potential were also detected. Most plasmid prophage coding sequences were, however, hypothetical proteins with unknown functions. Overall, this study highlights the ecological relevance of plasmids in the marine sponge microbiome and provides evidence that plasmids of sponge bacterial symbionts may represent an untapped resource of genes of biotechnological interest.
Collapse
|
4
|
Metabolic Engineering Strategies for Improved Lipid Production and Cellular Physiological Responses in Yeast Saccharomyces cerevisiae. J Fungi (Basel) 2022; 8:jof8050427. [PMID: 35628683 PMCID: PMC9144191 DOI: 10.3390/jof8050427] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2022] [Revised: 04/13/2022] [Accepted: 04/18/2022] [Indexed: 02/01/2023] Open
Abstract
Microbial lipids have been a hot topic in the field of metabolic engineering and synthetic biology due to their increased market and important applications in biofuels, oleochemicals, cosmetics, etc. This review first compares the popular hosts for lipid production and explains the four modules for lipid synthesis in yeast, including the fatty acid biosynthesis module, lipid accumulation module, lipid sequestration module, and fatty acid modification module. This is followed by a summary of metabolic engineering strategies that could be used for enhancing each module for lipid production. In addition, the efforts being invested in improving the production of value-added fatty acids in engineered yeast, such as cyclopropane fatty acid, ricinoleic acid, gamma linoleic acid, EPA, and DHA, are included. A discussion is further made on the potential relationships between lipid pathway engineering and consequential changes in cellular physiological properties, such as cell membrane integrity, intracellular reactive oxygen species level, and mitochondrial membrane potential. Finally, with the rapid development of synthetic biology tools, such as CRISPR genome editing tools and machine learning models, this review proposes some future trends that could be employed to engineer yeast with enhanced intracellular lipid production while not compromising much of its cellular health.
Collapse
|
5
|
Peng H, He L, Haritos VS. Flow-cytometry-based physiological characterisation and transcriptome analyses reveal a mechanism for reduced cell viability in yeast engineered for increased lipid content. BIOTECHNOLOGY FOR BIOFUELS 2019; 12:98. [PMID: 31044011 PMCID: PMC6477733 DOI: 10.1186/s13068-019-1435-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/02/2019] [Accepted: 04/12/2019] [Indexed: 06/09/2023]
Abstract
BACKGROUND Yeast has been the focus of development of cell biofactories for the production of lipids and interest in the field has been driven by the need for sustainably sourced lipids for use in a broad range of industrial applications. Previously, we reported a metabolic engineering strategy for enhanced lipid production in yeast which delivered high per-cell lipid but with low cell growth and compromised physiology. To investigate the relationship between lipid engineering and cellular physiological responses and to identify further metabolic engineering targets, we analysed transcriptomes and measured cell physiology parameters in engineered strains. RESULTS In the engineering strategy, the central carbon pathway was reprogrammed to provide more precursors for lipid production and lipid accumulation and sequestration steps were enhanced through the expression of heterologous genes. Genes coding for enzymes within the pentose phosphate, beta-oxidation pathways, ATP and NADPH biosynthesis had lower transcript levels in engineered cells. Meanwhile, flow-cytometry analysis of fluorescent-dye stained cells showed the highest reactive oxygen species (ROS) levels and mitochondrial membrane potential (Δψm) in cells with the highest lipid content, supporting the known relationship between mitochondrial activity and ROS generation. High intracellular ROS and low membrane integrity were not ameliorated by application of antioxidants. CONCLUSIONS The limited intracellular energy supplies and the unbalanced redox environment could be regarded as targets for further lipid engineering, similarly for native lipid accumulation genes that were upregulated. Thus, lipid pathway engineering has an important effect on the central carbon pathway, directing these towards lipid production and sacrificing the precursors, energy and cofactor supply to satisfy homeostatic metabolic requirements.
Collapse
Affiliation(s)
- Huadong Peng
- Department of Chemical Engineering, Monash University, Clayton, VIC 3800 Australia
- Present Address: Department of Bioengineering, Imperial College London, London, SW7 2AZ UK
| | - Lizhong He
- Department of Chemical Engineering, Monash University, Clayton, VIC 3800 Australia
| | - Victoria S. Haritos
- Department of Chemical Engineering, Monash University, Clayton, VIC 3800 Australia
| |
Collapse
|