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Tafrishi A, Trivedi V, Xing Z, Li M, Mewalal R, Cutler SR, Blaby I, Wheeldon I. Functional genomic screening in Komagataella phaffii enabled by high-activity CRISPR-Cas9 library. Metab Eng 2024; 85:73-83. [PMID: 39019250 DOI: 10.1016/j.ymben.2024.07.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2024] [Revised: 06/06/2024] [Accepted: 07/14/2024] [Indexed: 07/19/2024]
Abstract
CRISPR-based high-throughput genome-wide loss-of-function screens are a valuable approach to functional genetics and strain engineering. The yeast Komagataella phaffii is a host of particular interest in the biopharmaceutical industry and as a metabolic engineering host for proteins and metabolites. Here, we design and validate a highly active 6-fold coverage genome-wide sgRNA library for this biotechnologically important yeast containing 30,848 active sgRNAs targeting over 99% of its coding sequences. Conducting fitness screens in the absence of functional non-homologous end joining (NHEJ), the dominant DNA repair mechanism in K. phaffii, provides a quantitative means to assess the activity of each sgRNA in the library. This approach allows for the experimental validation of each guide's targeting activity, leading to more precise screening outcomes. We used this approach to conduct growth screens with glucose as the sole carbon source and identify essential genes. Comparative analysis of the called gene sets identified a core set of K. phaffii essential genes, many of which relate to metabolic engineering targets, including protein production, secretion, and glycosylation. The high activity, genome-wide CRISPR library developed here enables functional genomic screening in K. phaffii, applied here to gene essentiality classification, and promises to enable other genetic screens.
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Affiliation(s)
- Aida Tafrishi
- Chemical and Environmental Engineering, University of California-Riverside, Riverside, CA, 92521, USA
| | - Varun Trivedi
- Chemical and Environmental Engineering, University of California-Riverside, Riverside, CA, 92521, USA
| | - Zenan Xing
- Botany and Plant Sciences, University of California-Riverside, Riverside, CA, 92521, USA
| | - Mengwan Li
- Chemical and Environmental Engineering, University of California-Riverside, Riverside, CA, 92521, USA
| | - Ritesh Mewalal
- DOE Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Sean R Cutler
- Botany and Plant Sciences, University of California-Riverside, Riverside, CA, 92521, USA
| | - Ian Blaby
- DOE Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Ian Wheeldon
- Chemical and Environmental Engineering, University of California-Riverside, Riverside, CA, 92521, USA; Center for Industrial Biotechnology, University of California-Riverside, Riverside, CA, 92521, USA.
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2
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Tian X, Li J, Chen S. Key anti-freeze genes and pathways of Lanzhou lily (Lilium davidii, var. unicolor) during the seedling stage. PLoS One 2024; 19:e0299259. [PMID: 38512835 PMCID: PMC10956819 DOI: 10.1371/journal.pone.0299259] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Accepted: 02/07/2024] [Indexed: 03/23/2024] Open
Abstract
Temperature is one of the most important environmental factors for plant growth, as low-temperature freezing damage seriously affects the yield and distribution of plants. The Lanzhou lily (Lilium davidii, var. unicolor) is a famous ornamental plant with high ornamental value. Using an Illumina HiSeq transcriptome sequencing platform, sequencing was conducted on Lanzhou lilies exposed to two different temperature conditions: a normal temperature treatment at 20°C (A) and a cold treatment at -4°C (C). After being treated for 24 hours, a total of 5848 differentially expressed genes (DEGs) were identified, including 3478 significantly up regulated genes and 2370 significantly down regulated genes, accounting for 10.27% of the total number of DEGs. Quantitative real-time PCR (QRT-PCR) analysis showed that the expression trends of 10 randomly selected DEGs coincided with the results of high-throughput sequencing. In addition, genes responding to low-temperature stress were analyzed using the interaction regulatory network method. The anti-freeze pathway of Lanzhou lily was found to involve the photosynthetic and metabolic pathways, and the key freezing resistance genes were the OLEO3 gene, 9 CBF family genes, and C2H2 transcription factor c117817_g1 (ZFP). This lays the foundation for revealing the underlying mechanism of the molecular anti-freeze mechanism in Lanzhou lily.
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Affiliation(s)
- Xuehui Tian
- Department of Ecological Environment and Engineering, Yangling Vocational and Technical College, Shaanxi, Yangling, China
| | - Jianning Li
- Gansu Provincial Transportation Planning Survey and Design Institute Limited Liability Company, Lanzhou, Gansu Province, China
| | - Sihui Chen
- Department of Ecological Environment and Engineering, Yangling Vocational and Technical College, Shaanxi, Yangling, China
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3
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Liang Y, Gao S, Qi X, Valentovich LN, An Y. Progress in Gene Editing and Metabolic Regulation of Saccharomyces cerevisiae with CRISPR/Cas9 Tools. ACS Synth Biol 2024; 13:428-448. [PMID: 38326929 DOI: 10.1021/acssynbio.3c00685] [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] [Indexed: 02/09/2024]
Abstract
The CRISPR/Cas9 systems have been developed as tools for genetic engineering and metabolic engineering in various organisms. In this review, various aspects of CRISPR/Cas9 in Saccharomyces cerevisiae, from basic principles to practical applications, have been summarized. First, a comprehensive review has been conducted on the history of CRISPR/Cas9, successful cases of gene disruptions, and efficiencies of multiple DNA fragment insertions. Such advanced systems have accelerated the development of microbial engineering by reducing time and labor, and have enhanced the understanding of molecular genetics. Furthermore, the research progress of the CRISPR/Cas9-based systems in the production of high-value-added chemicals and the improvement of stress tolerance in S. cerevisiae have been summarized, which should have an important reference value for genetic and synthetic biology studies based on S. cerevisiae.
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Affiliation(s)
- Yaokun Liang
- College of Biosciences and Biotechnology, Shenyang Agricultural University, Shenyang 110065, China
| | - Song Gao
- College of Biosciences and Biotechnology, Shenyang Agricultural University, Shenyang 110065, China
| | - Xianghui Qi
- School of Life Sciences, Guangzhou University, Guangdong 511370, China
| | - Leonid N Valentovich
- Institute of Microbiology, National Academy of Sciences of Belarus, Minsk 220072, Belarus
| | - Yingfeng An
- College of Biosciences and Biotechnology, Shenyang Agricultural University, Shenyang 110065, China
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4
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Zhao M, Ma J, Zhang L, Qi H. Engineering strategies for enhanced heterologous protein production by Saccharomyces cerevisiae. Microb Cell Fact 2024; 23:32. [PMID: 38247006 PMCID: PMC10801990 DOI: 10.1186/s12934-024-02299-z] [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: 05/12/2023] [Accepted: 01/05/2024] [Indexed: 01/23/2024] Open
Abstract
Microbial proteins are promising substitutes for animal- and plant-based proteins. S. cerevisiae, a generally recognized as safe (GRAS) microorganism, has been frequently employed to generate heterologous proteins. However, constructing a universal yeast chassis for efficient protein production is still a challenge due to the varying properties of different proteins. With progress in synthetic biology, a multitude of molecular biology tools and metabolic engineering strategies have been employed to alleviate these issues. This review first analyses the advantages of protein production by S. cerevisiae. The most recent advances in improving heterologous protein yield are summarized and discussed in terms of protein hyperexpression systems, protein secretion engineering, glycosylation pathway engineering and systems metabolic engineering. Furthermore, the prospects for efficient and sustainable heterologous protein production by S. cerevisiae are also provided.
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Affiliation(s)
- Meirong Zhao
- Department of Biochemical Engineering, School of Chemical Engineering and Technology, Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (MOE), Tianjin University, Tianjin, 300350, China
| | - Jianfan Ma
- Department of Biochemical Engineering, School of Chemical Engineering and Technology, Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (MOE), Tianjin University, Tianjin, 300350, China
| | - Lei Zhang
- Department of Biochemical Engineering, School of Chemical Engineering and Technology, Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (MOE), Tianjin University, Tianjin, 300350, China
| | - Haishan Qi
- Department of Biochemical Engineering, School of Chemical Engineering and Technology, Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (MOE), Tianjin University, Tianjin, 300350, China.
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5
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Salazar-Cerezo S, de Vries RP, Garrigues S. Strategies for the Development of Industrial Fungal Producing Strains. J Fungi (Basel) 2023; 9:834. [PMID: 37623605 PMCID: PMC10455633 DOI: 10.3390/jof9080834] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Revised: 07/31/2023] [Accepted: 08/04/2023] [Indexed: 08/26/2023] Open
Abstract
The use of microorganisms in industry has enabled the (over)production of various compounds (e.g., primary and secondary metabolites, proteins and enzymes) that are relevant for the production of antibiotics, food, beverages, cosmetics, chemicals and biofuels, among others. Industrial strains are commonly obtained by conventional (non-GMO) strain improvement strategies and random screening and selection. However, recombinant DNA technology has made it possible to improve microbial strains by adding, deleting or modifying specific genes. Techniques such as genetic engineering and genome editing are contributing to the development of industrial production strains. Nevertheless, there is still significant room for further strain improvement. In this review, we will focus on classical and recent methods, tools and technologies used for the development of fungal production strains with the potential to be applied at an industrial scale. Additionally, the use of functional genomics, transcriptomics, proteomics and metabolomics together with the implementation of genetic manipulation techniques and expression tools will be discussed.
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Affiliation(s)
- Sonia Salazar-Cerezo
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands (R.P.d.V.)
| | - Ronald P. de Vries
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands (R.P.d.V.)
| | - Sandra Garrigues
- Food Biotechnology Department, Instituto de Agroquímica y Tecnología de Alimentos (IATA), Consejo Superior de Investigaciones Científicas (CSIC), Catedrático Agustín Escardino Benlloch 7, 46980 Paterna, VLC, Spain
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6
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Chetty BJ, Inokuma K, Hasunuma T, van Zyl WH, den Haan R. Improvement of cell-tethered cellulase activity in recombinant strains of Saccharomyces cerevisiae. Appl Microbiol Biotechnol 2022; 106:6347-6361. [PMID: 35951080 DOI: 10.1007/s00253-022-12114-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Revised: 07/27/2022] [Accepted: 07/28/2022] [Indexed: 11/30/2022]
Abstract
Consolidated bioprocessing (CBP) remains an attractive option for the production of commodity products from pretreated lignocellulose if a process-suitable organism can be engineered. The yeast Saccharomyces cerevisiae requires engineered cellulolytic activity to enable its use in CBP production of second-generation (2G) bioethanol. A promising strategy for heterologous cellulase production in yeast entails displaying enzymes on the cell surface by means of glycosylphosphatidylinositol (GPI) anchors. While strains producing a core set of cell-adhered cellulases that enabled crystalline cellulose hydrolysis have been created, secreted levels of enzyme were insufficient for complete cellulose hydrolysis. In fact, all reported recombinant yeast CBP candidates must overcome the drawback of generally low secretion titers. Rational strain engineering can be applied to enhance the secretion phenotype. This study aimed to improve the amount of cell-adhered cellulase activities of recombinant S. cerevisiae strains expressing a core set of four cellulases, through overexpression of genes that were previously shown to enhance cellulase secretion. Results showed significant increases in cellulolytic activity for all cell-adhered cellulase enzyme types. Cell-adhered cellobiohydrolase activity was improved by up to 101%, β-glucosidase activity by up to 99%, and endoglucanase activity by up to 231%. Improved hydrolysis of crystalline cellulose of up to 186% and improved ethanol yields from this substrate of 40-50% in different strain backgrounds were also observed. In addition, improvement in resistance to fermentation stressors was noted in some strains. These strains represent a step towards more efficient organisms for use in 2G biofuel production. KEY POINTS: • Cell-surface-adhered cellulase activity was improved in strains engineered for CBP. • Levels of improvement of activity were strain and enzyme dependent. • Crystalline cellulose conversion to ethanol could be improved up to 50%.
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Affiliation(s)
- Bronwyn Jean Chetty
- Department of Biotechnology, University of the Western Cape, Bellville, South Africa
| | - Kentaro Inokuma
- Graduate School of Science, Technology and Innovation, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe, 657-8501, Japan
| | - Tomohisa Hasunuma
- Graduate School of Science, Technology and Innovation, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe, 657-8501, Japan
- Engineering Biology Research Center, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe, 657-8501, Japan
| | | | - Riaan den Haan
- Department of Biotechnology, University of the Western Cape, Bellville, South Africa.
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7
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Wang Y, Li X, Chen X, Siewers V. CRISPR/Cas9-mediated point mutations improve α-amylase secretion in Saccharomyces cerevisiae. FEMS Yeast Res 2022; 22:6626025. [PMID: 35776981 PMCID: PMC9290899 DOI: 10.1093/femsyr/foac033] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Accepted: 06/28/2022] [Indexed: 11/12/2022] Open
Abstract
The rapid expansion of the application of pharmaceutical proteins and industrial enzymes requires robust microbial workhorses for high protein production. The budding yeast Saccharomyces cerevisiae is an attractive cell factory due to its ability to perform eukaryotic post-translational modifications and to secrete proteins. Many strategies have been used to engineer yeast platform strains for higher protein secretion capacity. Herein, we investigated a line of strains that have previously been selected after UV random mutagenesis for improved α-amylase secretion. A total of 42 amino acid altering point mutations identified in this strain line were reintroduced into the parental strain AAC to study their individual effects on protein secretion. These point mutations included missense mutations (amino acid substitution), nonsense mutations (stop codon generation), and frameshift mutations. For comparison, single gene deletions for the corresponding target genes were also performed in this study. A total of 11 point mutations and seven gene deletions were found to effectively improve α-amylase secretion. These targets were involved in several bioprocesses, including cellular stresses, protein degradation, transportation, mRNA processing and export, DNA replication, and repair, which indicates that the improved protein secretion capacity in the evolved strains is the result of the interaction of multiple intracellular processes. Our findings will contribute to the construction of novel cell factories for recombinant protein secretion.
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Affiliation(s)
- Yanyan Wang
- Department of Biology and Biological Engineering, Chalmers University of Technology, Kemivägen 10, SE-41296 Gothenburg, Sweden
| | - Xiaowei Li
- Department of Biology and Biological Engineering, Chalmers University of Technology, Kemivägen 10, SE-41296 Gothenburg, Sweden
| | - Xin Chen
- Department of Biology and Biological Engineering, Chalmers University of Technology, Kemivägen 10, SE-41296 Gothenburg, Sweden
- Novo Nordisk Foundation Center for Biosustainability, Chalmers University of Technology, Kemivägen 10, SE-41296 Gothenburg, Sweden
| | - Verena Siewers
- Corresponding author. Department of Biology and Biological Engineering, Chalmers University of Technology, Kemivägen 10, SE-41296 Gothenburg, Sweden. Tel: +46 (0)317723853; E-mail:
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8
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den Haan R, Rose SH, Cripwell RA, Trollope KM, Myburgh MW, Viljoen-Bloom M, van Zyl WH. Heterologous production of cellulose- and starch-degrading hydrolases to expand Saccharomyces cerevisiae substrate utilization: Lessons learnt. Biotechnol Adv 2021; 53:107859. [PMID: 34678441 DOI: 10.1016/j.biotechadv.2021.107859] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Revised: 10/14/2021] [Accepted: 10/15/2021] [Indexed: 12/28/2022]
Abstract
Selected strains of Saccharomyces cerevisiae are used for commercial bioethanol production from cellulose and starch, but the high cost of exogenous enzymes for substrate hydrolysis remains a challenge. This can be addressed through consolidated bioprocessing (CBP) where S. cerevisiae strains are engineered to express recombinant glycoside hydrolases during fermentation. Looking back at numerous strategies undertaken over the past four decades to improve recombinant protein production in S. cerevisiae, it is evident that various steps in the protein production "pipeline" can be manipulated depending on the protein of interest and its anticipated application. In this review, we briefly introduce some of the strategies and highlight lessons learned with regards to improved transcription, translation, post-translational modification and protein secretion of heterologous hydrolases. We examine how host strain selection and modification, as well as enzyme compatibility, are crucial determinants for overall success. Finally, we discuss how lessons from heterologous hydrolase expression can inform modern synthetic biology and genome editing tools to provide process-ready yeast strains in future. However, it is clear that the successful expression of any particular enzyme is still unpredictable and requires a trial-and-error approach.
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Affiliation(s)
- Riaan den Haan
- Department of Biotechnology, University of the Western Cape, Bellville, South Africa
| | - Shaunita H Rose
- Department of Microbiology, Stellenbosch University, Stellenbosch, South Africa
| | - Rosemary A Cripwell
- Department of Microbiology, Stellenbosch University, Stellenbosch, South Africa
| | - Kim M Trollope
- Department of Microbiology, Stellenbosch University, Stellenbosch, South Africa
| | - Marthinus W Myburgh
- Department of Microbiology, Stellenbosch University, Stellenbosch, South Africa
| | | | - Willem H van Zyl
- Department of Microbiology, Stellenbosch University, Stellenbosch, South Africa.
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9
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Helian Y, Gai Y, Fang H, Sun Y, Zhang D. A multistrategy approach for improving the expression of E. coli phytase in Pichia pastoris. J Ind Microbiol Biotechnol 2020; 47:1161-1172. [PMID: 32935229 DOI: 10.1007/s10295-020-02311-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Accepted: 09/07/2020] [Indexed: 01/26/2023]
Abstract
Phytase is an additive in animal feed that degrades phytic acid in plant material, reducing feeding costs, and pollution from fecal phosphorus excretion. A multistrategy approach was adopted to improve the expression of E. coli phytase in Pichia pastoris. We determined that the most suitable signal peptide for phytase secretion was an α-factor secretion signal with an initial enzyme activity of 153.51 U/mL. Increasing the copy number of this gene to four increased phytase enzyme activity by 234.35%. PDI overexpression and Pep4 gene knockout increased extracellular phytase production by 35.33% and 26.64%, respectively. By combining favorable factors affecting phytase expression and secretion, the enzyme activity of the phytase-engineered strain was amplified 384.60% compared with that of the original strain. We also evaluated the potential for the industrial production of the engineered strain using a 50-L fed-batch fermenter and achieved a total activity of 30,246 U/mL after 180 h of fermentation.
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Affiliation(s)
- Yuankun Helian
- School of Biological Engineering, Dalian Polytechnic University, No. 1 Qinggongyuan, Ganjingzi, Dalian, 116034, Liaoning, People's Republic of China.,Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 West 7th Avenue, Tianjin Airport Economic Area, Tianjin, 300308, People's Republic of China.,Key Laboratory of Systems Microbial Biotechnology, Chinese Academy of Sciences, 32 West 7th Avenue, Tianjin Airport Economic Area, Tianjin, 300308, People's Republic of China
| | - Yuanming Gai
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 West 7th Avenue, Tianjin Airport Economic Area, Tianjin, 300308, People's Republic of China.,Key Laboratory of Systems Microbial Biotechnology, Chinese Academy of Sciences, 32 West 7th Avenue, Tianjin Airport Economic Area, Tianjin, 300308, People's Republic of China
| | - Huan Fang
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 West 7th Avenue, Tianjin Airport Economic Area, Tianjin, 300308, People's Republic of China.,Key Laboratory of Systems Microbial Biotechnology, Chinese Academy of Sciences, 32 West 7th Avenue, Tianjin Airport Economic Area, Tianjin, 300308, People's Republic of China
| | - Yumei Sun
- School of Biological Engineering, Dalian Polytechnic University, No. 1 Qinggongyuan, Ganjingzi, Dalian, 116034, Liaoning, People's Republic of China.
| | - Dawei Zhang
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 West 7th Avenue, Tianjin Airport Economic Area, Tianjin, 300308, People's Republic of China. .,Key Laboratory of Systems Microbial Biotechnology, Chinese Academy of Sciences, 32 West 7th Avenue, Tianjin Airport Economic Area, Tianjin, 300308, People's Republic of China. .,University of Chinese Academy of Sciences, Beijing, 100049, People's Republic of China.
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10
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Exploiting strain diversity and rational engineering strategies to enhance recombinant cellulase secretion by Saccharomyces cerevisiae. Appl Microbiol Biotechnol 2020; 104:5163-5184. [PMID: 32337628 DOI: 10.1007/s00253-020-10602-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Revised: 03/26/2020] [Accepted: 03/31/2020] [Indexed: 12/14/2022]
Abstract
Consolidated bioprocessing (CBP) of lignocellulosic material into bioethanol has progressed in the past decades; however, several challenges still exist which impede the industrial application of this technology. Identifying the challenges that exist in all unit operations is crucial and needs to be optimised, but only the barriers related to the secretion of recombinant cellulolytic enzymes in Saccharomyces cerevisiae will be addressed in this review. Fundamental principles surrounding CBP as a biomass conversion platform have been established through the successful expression of core cellulolytic enzymes, namely β-glucosidases, endoglucanases, and exoglucanases (cellobiohydrolases) in S. cerevisiae. This review will briefly address the challenges involved in the construction of an efficient cellulolytic yeast, with particular focus on the secretion efficiency of cellulases from this host. Additionally, strategies for studying enhanced cellulolytic enzyme secretion, which include both rational and reverse engineering approaches, will be discussed. One such technique includes bio-engineering within genetically diverse strains, combining the strengths of both natural strain diversity and rational strain development. Furthermore, with the advancement in next-generation sequencing, studies that utilise this method of exploiting intra-strain diversity for industrially relevant traits will be reviewed. Finally, future prospects are discussed for the creation of ideal CBP strains with high enzyme production levels.Key Points• Several challenges are involved in the construction of efficient cellulolytic yeast, in particular, the secretion efficiency of cellulases from the hosts.• Strategies for enhancing cellulolytic enzyme secretion, a core requirement for CBP host microorganism development, include both rational and reverse engineering approaches.• One such technique includes bio-engineering within genetically diverse strains, combining the strengths of both natural strain diversity and rational strain development.
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11
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Davison SA, den Haan R, van Zyl WH. Identification of superior cellulase secretion phenotypes in haploids derived from natural Saccharomyces cerevisiae isolates. FEMS Yeast Res 2019; 19:5154912. [PMID: 30388213 DOI: 10.1093/femsyr/foy117] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Accepted: 10/31/2018] [Indexed: 01/11/2023] Open
Abstract
The yeast Saccharomyces cerevisiae is considered an important host for consolidated bioprocessing and the production of high titres of recombinant cellulases is required for efficient hydrolysis of lignocellulosic substrates to fermentable sugars. Since recombinant protein secretion profiles vary highly among different strain backgrounds, careful selection of robust strains with optimal secretion profiles is of crucial importance. Here, we construct and screen sets of haploid derivatives, derived from natural strain isolates YI13, FINI and YI59, for improved general cellulase secretion. This report details a novel approach that combines secretion profiles of strains and phenotypic responses to stresses known to influence the secretion pathway for the development of a phenotypic screen to isolate strains with improved secretory capacities. A clear distinction was observed between the YI13 haploid derivatives and industrial and laboratory counterparts, Ethanol Red and S288c, respectively. By using sub-lethal concentrations of the secretion stressor tunicamycin and cell wall stressor Congo Red, YI13 haploid derivative strains demonstrated tolerance profiles related to their heterologous secretion profiles. Our results demonstrated that a new screening technique combined with a targeted mating approach could produce a pool of novel strains capable of high cellulase secretion.
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Affiliation(s)
- Steffi A Davison
- Department of Microbiology, Stellenbosch University, Private Bag X1, Matieland 7602, South Africa
| | - Riaan den Haan
- Department of Biotechnology, University of the Western Cape, Bellville 7535, South Africa
| | - Willem Heber van Zyl
- Department of Microbiology, Stellenbosch University, Private Bag X1, Matieland 7602, South Africa
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12
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Zahrl RJ, Gasser B, Mattanovich D, Ferrer P. Detection and Elimination of Cellular Bottlenecks in Protein-Producing Yeasts. Methods Mol Biol 2019; 1923:75-95. [PMID: 30737735 DOI: 10.1007/978-1-4939-9024-5_2] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Yeasts are efficient cell factories and are commonly used for the production of recombinant proteins for biopharmaceutical and industrial purposes. For such products high levels of correctly folded proteins are needed, which sometimes requires improvement and engineering of the expression system. The article summarizes major breakthroughs that led to the efficient use of yeasts as production platforms and reviews bottlenecks occurring during protein production. Special focus is given to the metabolic impact of protein production. Furthermore, strategies that were shown to enhance secretion of recombinant proteins in different yeast species are presented.
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Affiliation(s)
- Richard J Zahrl
- Department of Biotechnology, University of Natural Resources and Life Sciences (BOKU), Vienna, Austria.,Austrian Centre of Industrial Biotechnology (acib), Vienna, Austria
| | - Brigitte Gasser
- Christian Doppler-Laboratory for Growth-Decoupled Protein Production in Yeast, Department of Biotechnology, University of Natural Resources and Life Sciences, Vienna, Austria.,Department of Biotechnology, University of Natural Resources and Life Sciences (BOKU) and Austrian Centre of Industrial Biotechnology (acib), Vienna, Austria
| | - Diethard Mattanovich
- Department of Biotechnology, University of Natural Resources and Life Sciences (BOKU) and Austrian Centre of Industrial Biotechnology (acib), Vienna, Austria
| | - Pau Ferrer
- Luxembourg Institute of Science and Technology, Belvaux, Luxembourg. .,Department of Chemical, Biological and Environmental Engineering, Universitat Autònoma de Barcelona, Bellaterra (Cerdanyola del Vallès), Catalonia, Spain.
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13
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Engineering the protein secretory pathway of Saccharomyces cerevisiae enables improved protein production. Proc Natl Acad Sci U S A 2018; 115:E11025-E11032. [PMID: 30397111 DOI: 10.1073/pnas.1809921115] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Baker's yeast Saccharomyces cerevisiae is one of the most important and widely used cell factories for recombinant protein production. Many strategies have been applied to engineer this yeast for improving its protein production capacity, but productivity is still relatively low, and with increasing market demand, it is important to identify new gene targets, especially targets that have synergistic effects with previously identified targets. Despite improved protein production, previous studies rarely focused on processes associated with intracellular protein retention. Here we identified genetic modifications involved in the secretory and trafficking pathways, the histone deacetylase complex, and carbohydrate metabolic processes as targets for improving protein secretion in yeast. Especially modifications on the endosome-to-Golgi trafficking was found to effectively reduce protein retention besides increasing protein secretion. Through combinatorial genetic manipulations of several of the newly identified gene targets, we enhanced the protein production capacity of yeast by more than fivefold, and the best engineered strains could produce 2.5 g/L of a fungal α-amylase with less than 10% of the recombinant protein retained within the cells, using fed-batch cultivation.
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14
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Integrated whole-genome and transcriptome sequence analysis reveals the genetic characteristics of a riboflavin-overproducing Bacillus subtilis. Metab Eng 2018; 48:138-149. [DOI: 10.1016/j.ymben.2018.05.022] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2018] [Revised: 05/17/2018] [Accepted: 05/31/2018] [Indexed: 11/23/2022]
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15
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Sindhu R, Binod P, Madhavan A, Beevi US, Mathew AK, Abraham A, Pandey A, Kumar V. Molecular improvements in microbial α-amylases for enhanced stability and catalytic efficiency. BIORESOURCE TECHNOLOGY 2017; 245:1740-1748. [PMID: 28478894 DOI: 10.1016/j.biortech.2017.04.098] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Revised: 04/18/2017] [Accepted: 04/24/2017] [Indexed: 06/07/2023]
Abstract
α-Amylases is one of the most important industrial enzyme which contributes to 25% of the industrial enzyme market. Though it is produced by plant, animals and microbial source, those from microbial source seems to have potential applications due to their stability and economic viability. However a large number of α-amylases from different sources have been detailed in the literature, only few numbers of them could withstand the harsh industrial conditions. Thermo-stability, pH tolerance, calcium independency and oxidant stability and starch hydrolyzing efficiency are the crucial qualities for α-amylase in starch based industries. Microbes can be genetically modified and fine tuning can be done for the production of enzymes with desired characteristics for specific applications. This review focuses on the native and recombinant α-amylases from microorganisms, their heterologous production and the recent molecular strategies which help to improve the properties of this industrial enzyme.
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Affiliation(s)
- Raveendran Sindhu
- Centre for Biofuels, National Institute for Interdisciplinary Science and Technology, CSIR, Trivandrum 695 019, India.
| | - Parameswaran Binod
- Centre for Biofuels, National Institute for Interdisciplinary Science and Technology, CSIR, Trivandrum 695 019, India
| | - Aravind Madhavan
- Centre for Biofuels, National Institute for Interdisciplinary Science and Technology, CSIR, Trivandrum 695 019, India; Rajiv Gandhi Centre for Biotechnology, Jagathy, Trivandrum 695 014, India
| | - Ummalyma Sabeela Beevi
- Centre for Biofuels, National Institute for Interdisciplinary Science and Technology, CSIR, Trivandrum 695 019, India; Institute of Bioresources and Sustainable Development, Takyelpat, Imphal 795 001, India
| | - Anil Kuruvilla Mathew
- Centre for Biofuels, National Institute for Interdisciplinary Science and Technology, CSIR, Trivandrum 695 019, India
| | - Amith Abraham
- Centre for Biofuels, National Institute for Interdisciplinary Science and Technology, CSIR, Trivandrum 695 019, India
| | - Ashok Pandey
- Centre for Biofuels, National Institute for Interdisciplinary Science and Technology, CSIR, Trivandrum 695 019, India; Center of Innovative and Applied Bioprocessing, Sector 81, Mohali, Punjab, India
| | - Vinod Kumar
- Center of Innovative and Applied Bioprocessing, Sector 81, Mohali, Punjab, India
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16
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Wang G, Huang M, Nielsen J. Exploring the potential of Saccharomyces cerevisiae for biopharmaceutical protein production. Curr Opin Biotechnol 2017; 48:77-84. [PMID: 28410475 DOI: 10.1016/j.copbio.2017.03.017] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2016] [Revised: 02/19/2017] [Accepted: 03/15/2017] [Indexed: 02/06/2023]
Abstract
Production of recombinant proteins by yeast plays a vital role in the biopharmaceutical industry. It is therefore desirable to develop yeast platform strains for over-production of various biopharmaceutical proteins, but this requires fundamental knowledge of the cellular machinery, especially the protein secretory pathway. Integrated analyses of multi-omics datasets can provide comprehensive understanding of cellular function, and can enable systems biology-driven and mathematical model-guided strain engineering. Rational engineering and introduction of trackable genetic modifications using synthetic biology tools, coupled with high-throughput screening are, however, also efficient approaches to relieve bottlenecks hindering high-level protein production. Here we review advances in systems biology and metabolic engineering of yeast for improving recombinant protein production.
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Affiliation(s)
- Guokun Wang
- Department of Biology and Biological Engineering, Chalmers University of Technology, SE41296 Gothenburg, Sweden
| | - Mingtao Huang
- Department of Biology and Biological Engineering, Chalmers University of Technology, SE41296 Gothenburg, Sweden; Novo Nordisk Foundation Center for Biosustainability, Chalmers University of Technology, SE41296 Gothenburg, Sweden
| | - Jens Nielsen
- Department of Biology and Biological Engineering, Chalmers University of Technology, SE41296 Gothenburg, Sweden; Novo Nordisk Foundation Center for Biosustainability, Chalmers University of Technology, SE41296 Gothenburg, Sweden; Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, DK2970 Hørsholm, Denmark.
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17
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de Ruijter JC, Jurgens G, Frey AD. Screening for novel genes of Saccharomyces cerevisiae involved in recombinant antibody production. FEMS Yeast Res 2016; 17:fow104. [PMID: 27956492 DOI: 10.1093/femsyr/fow104] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2016] [Accepted: 12/05/2016] [Indexed: 01/17/2023] Open
Abstract
Cost-effective manufacturing of biopharmaceuticals in non-mammalian hosts still requires tremendous efforts in strain development. In order to expedite identification of novel leads for strain engineering, we used a transposon-mutagenized yeast genomic DNA library to create a collection of Saccharomyces cerevisiae deletion strains expressing a full-length IgG antibody. Using a high-throughput screening, transformants with either significantly higher or lower IgG expression were selected. The integration site of the transposon in three of the selected strains was located by DNA sequencing. The inserted DNA lay within the VPS30 and TAR1 open reading frame, and upstream of the HEM13 open reading frame. The complete coding sequence of these genes was deleted in the wild-type strain background to confirm the IgG expression phenotypes. Production of recombinant antibody was increased 2-fold in the Δvps30 strain, but only mildly affected secretion levels in the Δtar1 strain. Remarkably, expression of endogenous yeast acid phosphatase was increased 1.7- and 2.4-fold in Δvps30 and Δtar1 strains. The study confirmed the power of genome-wide high-throughput screens for strain development and highlights the importance of using the target molecule during the screening process.
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Affiliation(s)
- Jorg C de Ruijter
- Department of Biotechnology and Chemical Technology, Aalto University, 02150 Espoo, Finland
| | | | - Alexander D Frey
- Department of Biotechnology and Chemical Technology, Aalto University, 02150 Espoo, Finland
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18
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Microfluidic screening and whole-genome sequencing identifies mutations associated with improved protein secretion by yeast. Proc Natl Acad Sci U S A 2015; 112:E4689-96. [PMID: 26261321 DOI: 10.1073/pnas.1506460112] [Citation(s) in RCA: 120] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
There is an increasing demand for biotech-based production of recombinant proteins for use as pharmaceuticals in the food and feed industry and in industrial applications. Yeast Saccharomyces cerevisiae is among preferred cell factories for recombinant protein production, and there is increasing interest in improving its protein secretion capacity. Due to the complexity of the secretory machinery in eukaryotic cells, it is difficult to apply rational engineering for construction of improved strains. Here we used high-throughput microfluidics for the screening of yeast libraries, generated by UV mutagenesis. Several screening and sorting rounds resulted in the selection of eight yeast clones with significantly improved secretion of recombinant α-amylase. Efficient secretion was genetically stable in the selected clones. We performed whole-genome sequencing of the eight clones and identified 330 mutations in total. Gene ontology analysis of mutated genes revealed many biological processes, including some that have not been identified before in the context of protein secretion. Mutated genes identified in this study can be potentially used for reverse metabolic engineering, with the objective to construct efficient cell factories for protein secretion. The combined use of microfluidics screening and whole-genome sequencing to map the mutations associated with the improved phenotype can easily be adapted for other products and cell types to identify novel engineering targets, and this approach could broadly facilitate design of novel cell factories.
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Tang H, Bao X, Shen Y, Song M, Wang S, Wang C, Hou J. Engineering protein folding and translocation improves heterologous protein secretion inSaccharomyces cerevisiae. Biotechnol Bioeng 2015; 112:1872-82. [DOI: 10.1002/bit.25596] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2014] [Revised: 03/11/2015] [Accepted: 03/16/2015] [Indexed: 11/10/2022]
Affiliation(s)
- Hongting Tang
- State Key Laboratory of Microbial Technology; Shandong University; Jinan 250100 China
| | - Xiaoming Bao
- State Key Laboratory of Microbial Technology; Shandong University; Jinan 250100 China
| | - Yu Shen
- State Key Laboratory of Microbial Technology; Shandong University; Jinan 250100 China
| | - Meihui Song
- State Key Laboratory of Microbial Technology; Shandong University; Jinan 250100 China
| | - Shenghuan Wang
- State Key Laboratory of Microbial Technology; Shandong University; Jinan 250100 China
| | - Chengqiang Wang
- State Key Laboratory of Microbial Technology; Shandong University; Jinan 250100 China
| | - Jin Hou
- State Key Laboratory of Microbial Technology; Shandong University; Jinan 250100 China
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Enhancement of phenol biodegradation by Pseudochrobactrum sp. through ultraviolet-induced mutation. Int J Mol Sci 2015; 16:7320-33. [PMID: 25837630 PMCID: PMC4425019 DOI: 10.3390/ijms16047320] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2014] [Revised: 03/16/2015] [Accepted: 03/20/2015] [Indexed: 11/21/2022] Open
Abstract
The phenol-degrading efficiency of Pseudochrobactrum sp. was enhanced by ultraviolet (UV) irradiation. First, a bacterial strain, Pseudochrobactrum sp. XF1, was isolated from the activated sludge in a coking plant. It was subjected to mutation by UV radiation for 120 s and a mutant strain with higher phenol-degrading efficiency, Pseudochrobactrum sp. XF1-UV, was selected. The mutant strain XF1-UV was capable of degrading 1800 mg/L phenol completely within 48 h and had higher tolerance to hydrogen ion concentration and temperature variation than the wild type. Haldane’s kinetic model was used to fit the exponential growth data and the following kinetic parameters were obtained: μmax = 0.092 h−1, Ks = 22.517 mg/L, and Ki = 1126.725 mg/L for XF1, whereas μmax = 0.110 h−1, Ks = 23.934 mg/L, and Ki = 1579.134 mg/L for XF1-UV. Both XF1 and XF1-UV degraded phenol through the ortho-pathway; but the phenol hydroxylase activity of XF1-UV1 was higher than that of XF1, therefore, the mutant strain biodegraded phenol faster. Taken together, our results suggest that Pseudochrobactrum sp. XF1-UV could be a promising candidate for bioremediation of phenol-containing wastewaters.
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Sun H, Liu Z, Zhao H, Ang EL. Recent advances in combinatorial biosynthesis for drug discovery. DRUG DESIGN DEVELOPMENT AND THERAPY 2015; 9:823-33. [PMID: 25709407 PMCID: PMC4334309 DOI: 10.2147/dddt.s63023] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Because of extraordinary structural diversity and broad biological activities, natural products have played a significant role in drug discovery. These therapeutically important secondary metabolites are assembled and modified by dedicated biosynthetic pathways in their host living organisms. Traditionally, chemists have attempted to synthesize natural product analogs that are important sources of new drugs. However, the extraordinary structural complexity of natural products sometimes makes it challenging for traditional chemical synthesis, which usually involves multiple steps, harsh conditions, toxic organic solvents, and byproduct wastes. In contrast, combinatorial biosynthesis exploits substrate promiscuity and employs engineered enzymes and pathways to produce novel “unnatural” natural products, substantially expanding the structural diversity of natural products with potential pharmaceutical value. Thus, combinatorial biosynthesis provides an environmentally friendly way to produce natural product analogs. Efficient expression of the combinatorial biosynthetic pathway in genetically tractable heterologous hosts can increase the titer of the compound, eventually resulting in less expensive drugs. In this review, we will discuss three major strategies for combinatorial biosynthesis: 1) precursor-directed biosynthesis; 2) enzyme-level modification, which includes swapping of the entire domains, modules and subunits, site-specific mutagenesis, and directed evolution; 3) pathway-level recombination. Recent examples of combinatorial biosynthesis employing these strategies will also be highlighted in this review.
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Affiliation(s)
- Huihua Sun
- Metabolic Engineering Research Laboratory, Institute of Chemical and Engineering Sciences, Agency for Science, Technology and Research, Singapore
| | - Zihe Liu
- Metabolic Engineering Research Laboratory, Institute of Chemical and Engineering Sciences, Agency for Science, Technology and Research, Singapore
| | - Huimin Zhao
- Metabolic Engineering Research Laboratory, Institute of Chemical and Engineering Sciences, Agency for Science, Technology and Research, Singapore ; Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Ee Lui Ang
- Metabolic Engineering Research Laboratory, Institute of Chemical and Engineering Sciences, Agency for Science, Technology and Research, Singapore
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