Environmental sustainability is an increasingly important issue in industry.As an environmentally friendly and sustainable way,constructing microbial cell factories to produce all kinds of valuable products has attrac...Environmental sustainability is an increasingly important issue in industry.As an environmentally friendly and sustainable way,constructing microbial cell factories to produce all kinds of valuable products has attracted more and more attention.In the process of constructing microbial cell factories,systems biology plays a crucial role.This review summarizes the recent applications of systems biology in the design and construction of microbial cell factories from four perspectives,including functional genes/enzymes discovery,bottleneck pathways identification,strains tolerance improvement and design and construction of synthetic microbial consortia.Systems biology tools can be employed to identify functional genes/enzymes involved in the biosynthetic pathways of products.These discovered genes are introduced into appropriate chassis strains to build engineering microorganisms capable of producing products.Subsequently,systems biology tools are used to identify bottleneck pathways,improve strains tolerance and guide design and construction of synthetic microbial consortia,resulting in increasing the yield of engineered strains and constructing microbial cell factories successfully.展开更多
The use of traditional chemical catalysis to produce chemicals has a series of drawbacks,such as high dependence on fossil resources,high energy consumption,and environmental pollution.With the development of syntheti...The use of traditional chemical catalysis to produce chemicals has a series of drawbacks,such as high dependence on fossil resources,high energy consumption,and environmental pollution.With the development of synthetic biology and metabolic engineering,the use of renewable biomass raw materials for chemicals synthesis by constructing efficient microbial cell factories is a green way to replace traditional chemical catalysis and traditional microbial fermentation.This review mainly summarizes several types of bulk chemicals and high value-added chemicals using metabolic engineering and synthetic biology strategies to achieve efficient microbial production.In addition,this review also summarizes several strategies for effectively regulating microbial cell metabolism.These strategies can achieve the coupling balance of material and energy by regulating intracellular material metabolism or energy metabolism,and promote the efficient production of target chemicals by microorganisms.展开更多
Microbial biorefineries to produce chemicals from renewable feedstock provides attractive advantages,including mild reaction conditions and sustainable manufacturing.However,low-efficiency biorefineries always result ...Microbial biorefineries to produce chemicals from renewable feedstock provides attractive advantages,including mild reaction conditions and sustainable manufacturing.However,low-efficiency biorefineries always result in an uncompetitive biological process compared to the current petrochemical process.Thus,improving microbial capacity to maximize product yield,productivity,and titer has been recognized as a central goal for bioengineers and biochemists.The knowledge of cellular biochemistry has enabled the regulation of microbial physiology to couple with chemical production.The rapid development in metabolic engineering provides diverse strategies to enhance the efficiency of chemical biosynthesis pathways.New synthetic biology tools as well as novel regulatory targets also offer the opportunity to improve biorefinery environmental adaptivity.In this review,the recent advances in building efficient biorefineries were showcased.In addition,the challenges and future perspectives of microbial host engineering for increased microbial capacity of a biorefinery were discussed.展开更多
The global market demand for natural astaxanthin is rapidly increasing owing to its safety,the potential health benefits,and the diverse applications in food and pharmaceutical industries.The major native producers of...The global market demand for natural astaxanthin is rapidly increasing owing to its safety,the potential health benefits,and the diverse applications in food and pharmaceutical industries.The major native producers of natural astaxanthin on industrial scale are the alga Haematococcus pluvialis and the yeast Xanthopyllomyces dendrorhous.However,the natural production via these native producers is facing challenges of limited yield and high cost of cultivation and extraction.Alternatively,astaxanthin production via metabolically engineered non-native microbial cell factories such as Escherichia coli,Saccharomyces cerevisiae and Yarrowia lipolytica is another promising strategy to overcome these limitations.In this review we summarize the recent scientific and biotechnological progresses on astaxanthin biosynthetic pathways,transcriptional regulations,the interrelation with lipid metabolism,engineering strategies as well as fermentation process control in major native and non-native astaxanthin producers.These progresses illuminate the prospects of producing astaxanthin by microbial cell factories on industrial scale.展开更多
Cytochrome P450(CYP)enzymes play crucial roles during the evolution and diversification of ancestral monocel-lular eukaryotes into multicellular eukaryotic organisms due to their essential functionalities including ca...Cytochrome P450(CYP)enzymes play crucial roles during the evolution and diversification of ancestral monocel-lular eukaryotes into multicellular eukaryotic organisms due to their essential functionalities including catalysis of housekeeping biochemical reactions,synthesis of diverse metabolites,detoxification of xenobiotics,and con-tribution to environmental adaptation.Eukaryotic CYPs with versatile functionalities are undeniably regarded as promising biocatalysts with great potential for biotechnological,pharmaceutical and chemical industry applica-tions.Nevertheless,the modes of action and the challenges associated with these membrane-bound proteins have hampered the effective utilization of eukaryotic CYPs in a broader range.This review is focused on comprehen-sive and consolidated approaches to address the core challenges in heterologous expression of membrane-bound eukaryotic CYPs in different surrogate microbial cell factories,aiming to provide key insights for better studies and applications of diverse eukaryotic CYPs in the future.We also highlight the functional significance of the previously underrated cytochrome P450 reductases(CPRs)and provide a rational justification on the progression of CPR from auxiliary redox partner to function modulator in CYP catalysis.展开更多
Microbial fermentation has contributed to 80%of global amino acid production.The key to microbial fermentation is to obtain fermentation strains with high performance to produce target amino acids with a high yield.Th...Microbial fermentation has contributed to 80%of global amino acid production.The key to microbial fermentation is to obtain fermentation strains with high performance to produce target amino acids with a high yield.These strains are primarily derived from screening enormous mutant libraries.Therefore,a high-throughput,rapid,accurate,and universal screening strategy for amino acid overproducers has become a guarantee for ob-taining optional amino acid overproducers.In recent years,the rapid development of various novel screening strategies has been witnessed.However,proper analysis and discussion of these innovative technologies are lacking.Here we systematically reviewed recent advances in screening strategies:the auxotrophic-based strategy,the biosensor-based strategy,and the latest translation-based screening strategy.The design principle,application scope,working efficiency,screening accuracy,and universality of these strategies were discussed in detail.The potential for screening nonstandard amino acid overproducers was also analyzed.Guidance for the improvement of future screening strategies is provided in this review,which could expedite the reconstruction of amino acid overproducers and help promote the fermentation industry to reduce cost,increase yield,and improve quality.展开更多
10-DeacetylbaccatinⅢ(10-DAB)C10 acetylation is an indispensable procedure for Taxol semi-synthesis,which often requires harsh conditions.10-DeacetylbaccatinⅢ-10-β-O-acetyltransferase(DBAT)catalyzes the acetylation ...10-DeacetylbaccatinⅢ(10-DAB)C10 acetylation is an indispensable procedure for Taxol semi-synthesis,which often requires harsh conditions.10-DeacetylbaccatinⅢ-10-β-O-acetyltransferase(DBAT)catalyzes the acetylation but acetyl-CoA supply remains a key limiting factor.Here we refactored the innate biosynthetic pathway of acetyl-CoA in Escherichia coli and obtained a chassis with acetyl-CoA productivity over three times higher than that of the host cell.Then,we constructed a microbial cell factory by introducing DBAT gene into this chassis for efficiently converting 10-DAB into baccatinⅢ.We found that baccatinⅢcould be efficiently deacetylated into 10-DAB by DBAT with CoASH and K+under alkaline condition.Thus,we fed acetic acid to the engineered strain both for serving as a substrate of acetyl-CoA biosynthesis and for alleviating the deacetylation of baccatinⅢ.The fermentation conditions were optimized and the baccatinⅢtiters reached 2,3 and 4.6 g/L,respectively,in a 3-L bioreactor culture when 2,3 and 6 g/L of 10-DAB were supplied.Our study provides an environmentfriendly approach for the large scale 10-DAB acetylation without addition of acetyl-CoA in the industrial Taxol semi-synthesis.The finding of DBAT deacetylase activity may broaden its application in the structural modification of pharmaceutically important lead compounds.展开更多
Both natural ginsenoside F2 and unnatural ginsenoside 3β,20S-Di-O-Glc-DM were reported to exhibit anti-tumor activity.Traditional approaches for producing them rely on direct extraction from Panax ginseng,enzymatic c...Both natural ginsenoside F2 and unnatural ginsenoside 3β,20S-Di-O-Glc-DM were reported to exhibit anti-tumor activity.Traditional approaches for producing them rely on direct extraction from Panax ginseng,enzymatic catalysis or chemical synthesis,all of which result in low yield and high cost.Metabolic engineering of microbes has been recognized as a green and sustainable biotechnology to produce natural and unnatural products.Hence we engineered the complete biosynthetic pathways of F2 and 3β,20S-Di-OGlc-DM in Saccharomyces cerevisiae via the CRISPR/Cas9 system.The titers of F2 and 3β,20S-Di-O-GlcDM were increased from 1.2 to 21.0 mg/L and from 82.0 to 346.1 mg/L at shake flask level,respectively,by multistep metabolic engineering strategies.Additionally,pharmacological evaluation showed that both F2and 3β,20S-Di-O-Glc-DM exhibited anti-pancreatic cancer activity and the activity of 3β,20S-Di-O-GlcDM was even better.Furthermore,the titer of 3β,20S-Di-O-Glc-DM reached 2.6 g/L by fed-batch fermentation in a 3 L bioreactor.To our knowledge,this is the first report on demonstrating the anti-pancreatic cancer activity of F2 and 3β,20S-Di-O-Glc-DM,and achieving their de novo biosynthesis by the engineered yeasts.Our work presents an alternative approach to produce F2 and 3β,20S-Di-O-Glc-DM from renewable biomass,which lays a foundation for drug research and development.展开更多
Phloretin is an important skin-lightening and depigmenting agent from the peel of apples. Although de novo production of phloretin has been realized in microbes using the natural pathway from plants, the efficiency of...Phloretin is an important skin-lightening and depigmenting agent from the peel of apples. Although de novo production of phloretin has been realized in microbes using the natural pathway from plants, the efficiency of phloretin production is still not enough for industrial application. Here, we established an artificial pathway in the yeast to produce phloretin via assembling two genes of p-coumaroyl-CoA ligase(4CL) and chalcone synthase(CHS). CHS is a key enzyme which conventionally condenses a CoA-tethered starter with three molecules of malonyl-CoA to form the backbone of flavonoids. However, there was 33% of byproduct generated via CHS by condensing two molecules of malonyl-CoA during the fermentation process. Hence, we introduced a more efficient CHS and improved the supply of malonyl-CoA through two pathways;the by-product ratio was decreased from 33% to 17% and the production of phloretin was improved from 48 to 83.2 mg L^(-1). Finally, a fed-batch fermentation process was optimized and the production of phloretin reached 619.5 mg L^(-1), which was 14-fold higher than that of the previous studies. Our work established a platform for the biosynthesis of phloretin from the low-cost raw material 3-(4-hydroxyphenyl) propanoic acid and also illustrated the potential for industrial scale bio-manufacturing of phloretin.展开更多
The production of biofuels and biochemicals derived from microbial fermentation has received a lot of attention and interest in light of concerns about the depletion of fossil fuel resources and climatic degeneration....The production of biofuels and biochemicals derived from microbial fermentation has received a lot of attention and interest in light of concerns about the depletion of fossil fuel resources and climatic degeneration.However,the economic viability of feedstocks for biological conversion remains a barrier,urging researchers to develop renewable and sustainable low-cost carbon sources for future bioindustries.Owing to the numerous advantages,acetate has been regarded as a promising feedstock targeting the production of acetyl-CoA-derived chemicals.This review aims to highlight the potential of acetate as a building block in industrial biotechnology for the production of bio-based chemicals with metabolic engineering.Different alternative approaches and routes com-prised of lignocellulosic biomass,waste streams,and C1 gas for acetate generation are briefly described and evaluated.Then,a thorough explanation of the metabolic pathway for biotechnological acetate conversion,cel-lular transport,and toxin tolerance is described.Particularly,current developments in metabolic engineering of the manufacture of biochemicals from acetate are summarized in detail,with various microbial cell factories and strategies proposed to improve acetate assimilation and enhance product formation.Challenges and future development for acetate generation and assimilation as well as chemicals production from acetate is eventually shown.This review provides an overview of the current status of acetate utilization and proves the great potential of acetate with metabolic engineering in industrial biotechnology.展开更多
Microbial cell factories(MCFs)and cell-free systems(CFSs)are generally considered as two unrelated approaches for the biosynthesis of biomolecules.In the current study,two systems were combined together for the overpr...Microbial cell factories(MCFs)and cell-free systems(CFSs)are generally considered as two unrelated approaches for the biosynthesis of biomolecules.In the current study,two systems were combined together for the overproduction of agroclavine(AC),a structurally complex ergot alkaloid.The whole biosynthetic pathway for AC was split into the early pathway and the late pathway at the point of the FAD-linked oxidoreductase EasE,which was reconstituted in an MCF(Aspergillus nidulans)and a four-enzyme CFS,respectively.The final titer of AC of this combined system is 1209 mg/L,which is the highest one that has been reported so far,to the best of our knowledge.The development of such a combined route could potentially avoid the limitations of both MCF and CFS systems,and boost the production of complex ergot alkaloids with polycyclic ring systems.展开更多
基金by the National Key Research and Development Program of China (2019YFA0706900)National Natural Science Foundation of China (22278310).
文摘Environmental sustainability is an increasingly important issue in industry.As an environmentally friendly and sustainable way,constructing microbial cell factories to produce all kinds of valuable products has attracted more and more attention.In the process of constructing microbial cell factories,systems biology plays a crucial role.This review summarizes the recent applications of systems biology in the design and construction of microbial cell factories from four perspectives,including functional genes/enzymes discovery,bottleneck pathways identification,strains tolerance improvement and design and construction of synthetic microbial consortia.Systems biology tools can be employed to identify functional genes/enzymes involved in the biosynthetic pathways of products.These discovered genes are introduced into appropriate chassis strains to build engineering microorganisms capable of producing products.Subsequently,systems biology tools are used to identify bottleneck pathways,improve strains tolerance and guide design and construction of synthetic microbial consortia,resulting in increasing the yield of engineered strains and constructing microbial cell factories successfully.
基金This work was financially supported by the National Natural Science Foundation of China(Grant Nos.21811530003,21861132017,U1663227,21706006)。
文摘The use of traditional chemical catalysis to produce chemicals has a series of drawbacks,such as high dependence on fossil resources,high energy consumption,and environmental pollution.With the development of synthetic biology and metabolic engineering,the use of renewable biomass raw materials for chemicals synthesis by constructing efficient microbial cell factories is a green way to replace traditional chemical catalysis and traditional microbial fermentation.This review mainly summarizes several types of bulk chemicals and high value-added chemicals using metabolic engineering and synthetic biology strategies to achieve efficient microbial production.In addition,this review also summarizes several strategies for effectively regulating microbial cell metabolism.These strategies can achieve the coupling balance of material and energy by regulating intracellular material metabolism or energy metabolism,and promote the efficient production of target chemicals by microorganisms.
基金supported by the National Key R and D Program of China(2020YFA0908300)the Science Fund for Creative Research Groups of the National Natural Science Foundation of China(32021005)+1 种基金the Key Program of the National Natural Science Foundation of China(22038005)the National Natural Science Foundation of China(32070124,22008087).
文摘Microbial biorefineries to produce chemicals from renewable feedstock provides attractive advantages,including mild reaction conditions and sustainable manufacturing.However,low-efficiency biorefineries always result in an uncompetitive biological process compared to the current petrochemical process.Thus,improving microbial capacity to maximize product yield,productivity,and titer has been recognized as a central goal for bioengineers and biochemists.The knowledge of cellular biochemistry has enabled the regulation of microbial physiology to couple with chemical production.The rapid development in metabolic engineering provides diverse strategies to enhance the efficiency of chemical biosynthesis pathways.New synthetic biology tools as well as novel regulatory targets also offer the opportunity to improve biorefinery environmental adaptivity.In this review,the recent advances in building efficient biorefineries were showcased.In addition,the challenges and future perspectives of microbial host engineering for increased microbial capacity of a biorefinery were discussed.
基金We gratefully acknowledge the financial support from the National Key Research and Development Program of China(2020YFA0907800)Shandong Jincheng Bio-Pharmaceutical Co.,Ltd.
文摘The global market demand for natural astaxanthin is rapidly increasing owing to its safety,the potential health benefits,and the diverse applications in food and pharmaceutical industries.The major native producers of natural astaxanthin on industrial scale are the alga Haematococcus pluvialis and the yeast Xanthopyllomyces dendrorhous.However,the natural production via these native producers is facing challenges of limited yield and high cost of cultivation and extraction.Alternatively,astaxanthin production via metabolically engineered non-native microbial cell factories such as Escherichia coli,Saccharomyces cerevisiae and Yarrowia lipolytica is another promising strategy to overcome these limitations.In this review we summarize the recent scientific and biotechnological progresses on astaxanthin biosynthetic pathways,transcriptional regulations,the interrelation with lipid metabolism,engineering strategies as well as fermentation process control in major native and non-native astaxanthin producers.These progresses illuminate the prospects of producing astaxanthin by microbial cell factories on industrial scale.
基金supported by the National Key Research and Develop-ment Program of China(2019YFA0706900)the National Natural Sci-ence Foundation of China(32025001 and 21472204)the Shandong Provincial Natural Science Foundation(ZR2019ZD20).
文摘Cytochrome P450(CYP)enzymes play crucial roles during the evolution and diversification of ancestral monocel-lular eukaryotes into multicellular eukaryotic organisms due to their essential functionalities including catalysis of housekeeping biochemical reactions,synthesis of diverse metabolites,detoxification of xenobiotics,and con-tribution to environmental adaptation.Eukaryotic CYPs with versatile functionalities are undeniably regarded as promising biocatalysts with great potential for biotechnological,pharmaceutical and chemical industry applica-tions.Nevertheless,the modes of action and the challenges associated with these membrane-bound proteins have hampered the effective utilization of eukaryotic CYPs in a broader range.This review is focused on comprehen-sive and consolidated approaches to address the core challenges in heterologous expression of membrane-bound eukaryotic CYPs in different surrogate microbial cell factories,aiming to provide key insights for better studies and applications of diverse eukaryotic CYPs in the future.We also highlight the functional significance of the previously underrated cytochrome P450 reductases(CPRs)and provide a rational justification on the progression of CPR from auxiliary redox partner to function modulator in CYP catalysis.
基金supported by the National Key R&D Program of China(2019YFA0906500)the National Natural Science Foundation of China(32000059)+1 种基金the Innovation Team Project of Colleges and Universities in Jinan(2019GXRC033)the Fundamental Research Funds for the Central Universities.
文摘Microbial fermentation has contributed to 80%of global amino acid production.The key to microbial fermentation is to obtain fermentation strains with high performance to produce target amino acids with a high yield.These strains are primarily derived from screening enormous mutant libraries.Therefore,a high-throughput,rapid,accurate,and universal screening strategy for amino acid overproducers has become a guarantee for ob-taining optional amino acid overproducers.In recent years,the rapid development of various novel screening strategies has been witnessed.However,proper analysis and discussion of these innovative technologies are lacking.Here we systematically reviewed recent advances in screening strategies:the auxotrophic-based strategy,the biosensor-based strategy,and the latest translation-based screening strategy.The design principle,application scope,working efficiency,screening accuracy,and universality of these strategies were discussed in detail.The potential for screening nonstandard amino acid overproducers was also analyzed.Guidance for the improvement of future screening strategies is provided in this review,which could expedite the reconstruction of amino acid overproducers and help promote the fermentation industry to reduce cost,increase yield,and improve quality.
基金supported by the National Key Research and Development Program of China(grant Nos.2018YFA0901900 and 2020YFA0908003)the Drug Innovation Major Project(grant No.2018ZX09711001-006-001,China)+2 种基金the National Natural Science Foundation of China(grant No.81573325)the CAMS Innovation Fund for Medical Sciences(CIFMS,(grant No.2017-I2M-2-004,2019-I2M-1-005,China)PUMC Disciplinary Development of Synthetic Biology(201920100801,China)。
文摘10-DeacetylbaccatinⅢ(10-DAB)C10 acetylation is an indispensable procedure for Taxol semi-synthesis,which often requires harsh conditions.10-DeacetylbaccatinⅢ-10-β-O-acetyltransferase(DBAT)catalyzes the acetylation but acetyl-CoA supply remains a key limiting factor.Here we refactored the innate biosynthetic pathway of acetyl-CoA in Escherichia coli and obtained a chassis with acetyl-CoA productivity over three times higher than that of the host cell.Then,we constructed a microbial cell factory by introducing DBAT gene into this chassis for efficiently converting 10-DAB into baccatinⅢ.We found that baccatinⅢcould be efficiently deacetylated into 10-DAB by DBAT with CoASH and K+under alkaline condition.Thus,we fed acetic acid to the engineered strain both for serving as a substrate of acetyl-CoA biosynthesis and for alleviating the deacetylation of baccatinⅢ.The fermentation conditions were optimized and the baccatinⅢtiters reached 2,3 and 4.6 g/L,respectively,in a 3-L bioreactor culture when 2,3 and 6 g/L of 10-DAB were supplied.Our study provides an environmentfriendly approach for the large scale 10-DAB acetylation without addition of acetyl-CoA in the industrial Taxol semi-synthesis.The finding of DBAT deacetylase activity may broaden its application in the structural modification of pharmaceutically important lead compounds.
基金financially supported by the grants of CAMS Innovation Fund for Medical Sciences(CIFMS)(2021-I2M-1-029,China)the Beijing Natural Science Foundation(7212158,China)+1 种基金the National Natural Science Foundation of China(81673341)PUMC Disciplinary Development of Synthetic Biology(201920100801,China)。
文摘Both natural ginsenoside F2 and unnatural ginsenoside 3β,20S-Di-O-Glc-DM were reported to exhibit anti-tumor activity.Traditional approaches for producing them rely on direct extraction from Panax ginseng,enzymatic catalysis or chemical synthesis,all of which result in low yield and high cost.Metabolic engineering of microbes has been recognized as a green and sustainable biotechnology to produce natural and unnatural products.Hence we engineered the complete biosynthetic pathways of F2 and 3β,20S-Di-OGlc-DM in Saccharomyces cerevisiae via the CRISPR/Cas9 system.The titers of F2 and 3β,20S-Di-O-GlcDM were increased from 1.2 to 21.0 mg/L and from 82.0 to 346.1 mg/L at shake flask level,respectively,by multistep metabolic engineering strategies.Additionally,pharmacological evaluation showed that both F2and 3β,20S-Di-O-Glc-DM exhibited anti-pancreatic cancer activity and the activity of 3β,20S-Di-O-GlcDM was even better.Furthermore,the titer of 3β,20S-Di-O-Glc-DM reached 2.6 g/L by fed-batch fermentation in a 3 L bioreactor.To our knowledge,this is the first report on demonstrating the anti-pancreatic cancer activity of F2 and 3β,20S-Di-O-Glc-DM,and achieving their de novo biosynthesis by the engineered yeasts.Our work presents an alternative approach to produce F2 and 3β,20S-Di-O-Glc-DM from renewable biomass,which lays a foundation for drug research and development.
基金financially supported by Talents Team Construction Fund of Northwestern Polytechnical University (NWPU)the National Natural Science Foundation of China (31701722)+1 种基金the China Postdoctoral Science Foundation (2017M620471)the National Natural Science Foundation of China (31901026)。
文摘Phloretin is an important skin-lightening and depigmenting agent from the peel of apples. Although de novo production of phloretin has been realized in microbes using the natural pathway from plants, the efficiency of phloretin production is still not enough for industrial application. Here, we established an artificial pathway in the yeast to produce phloretin via assembling two genes of p-coumaroyl-CoA ligase(4CL) and chalcone synthase(CHS). CHS is a key enzyme which conventionally condenses a CoA-tethered starter with three molecules of malonyl-CoA to form the backbone of flavonoids. However, there was 33% of byproduct generated via CHS by condensing two molecules of malonyl-CoA during the fermentation process. Hence, we introduced a more efficient CHS and improved the supply of malonyl-CoA through two pathways;the by-product ratio was decreased from 33% to 17% and the production of phloretin was improved from 48 to 83.2 mg L^(-1). Finally, a fed-batch fermentation process was optimized and the production of phloretin reached 619.5 mg L^(-1), which was 14-fold higher than that of the previous studies. Our work established a platform for the biosynthesis of phloretin from the low-cost raw material 3-(4-hydroxyphenyl) propanoic acid and also illustrated the potential for industrial scale bio-manufacturing of phloretin.
基金supported by Agricultural Science and Technology In-novation Project of Chinese Academy of Agricultural Sciences(CAAS-ASTIP-2016-BIOMA)Central Public-Interest Scientific Institution Basal Research Fund(1610012022001_03104)+2 种基金Central Public-Interest Scien-tific Institution Basal Research Fund(1610012022009-03102)Sichuan Provincial Science and Technology Research Project(2022YFN0062)Sichuan Science and Technology Program(2022YFS0460).
文摘The production of biofuels and biochemicals derived from microbial fermentation has received a lot of attention and interest in light of concerns about the depletion of fossil fuel resources and climatic degeneration.However,the economic viability of feedstocks for biological conversion remains a barrier,urging researchers to develop renewable and sustainable low-cost carbon sources for future bioindustries.Owing to the numerous advantages,acetate has been regarded as a promising feedstock targeting the production of acetyl-CoA-derived chemicals.This review aims to highlight the potential of acetate as a building block in industrial biotechnology for the production of bio-based chemicals with metabolic engineering.Different alternative approaches and routes com-prised of lignocellulosic biomass,waste streams,and C1 gas for acetate generation are briefly described and evaluated.Then,a thorough explanation of the metabolic pathway for biotechnological acetate conversion,cel-lular transport,and toxin tolerance is described.Particularly,current developments in metabolic engineering of the manufacture of biochemicals from acetate are summarized in detail,with various microbial cell factories and strategies proposed to improve acetate assimilation and enhance product formation.Challenges and future development for acetate generation and assimilation as well as chemicals production from acetate is eventually shown.This review provides an overview of the current status of acetate utilization and proves the great potential of acetate with metabolic engineering in industrial biotechnology.
基金This study was supported by the National Key Research and Development Program of China(grant nos.2021YFC2100600,2019YFA0905100 and 2018YFA0901600)the National Natural Science Foundation of China(grant nos.31872614,32022002,21977113)+1 种基金the Youth Scientists Innovation Promotion Association of CAS(2019090)to S.S.G.,Innovative Cross Team project of Chinese Academy of Sciences,CAS(grant no.JCTD-2019-06)Shandong Provincial Natural Science Foundation(Major Basic Research Projects)(grant no.ZR2019ZD18).
文摘Microbial cell factories(MCFs)and cell-free systems(CFSs)are generally considered as two unrelated approaches for the biosynthesis of biomolecules.In the current study,two systems were combined together for the overproduction of agroclavine(AC),a structurally complex ergot alkaloid.The whole biosynthetic pathway for AC was split into the early pathway and the late pathway at the point of the FAD-linked oxidoreductase EasE,which was reconstituted in an MCF(Aspergillus nidulans)and a four-enzyme CFS,respectively.The final titer of AC of this combined system is 1209 mg/L,which is the highest one that has been reported so far,to the best of our knowledge.The development of such a combined route could potentially avoid the limitations of both MCF and CFS systems,and boost the production of complex ergot alkaloids with polycyclic ring systems.
