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Ma Y, Ye JW, Lin Y, Yi X, Wang X, Wang H, Huang R, Wu F, Wu Q, Liu X, Chen GQ. Flux optimization using multiple promoters in Halomonas bluephagenesis as a model chassis of the next generation industrial biotechnology. Metab Eng 2024; 81:249-261. [PMID: 38159902 DOI: 10.1016/j.ymben.2023.12.011] [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: 10/15/2023] [Revised: 12/16/2023] [Accepted: 12/24/2023] [Indexed: 01/03/2024]
Abstract
Predictability and robustness are challenges for bioproduction because of the unstable intracellular synthetic activities. With the deeper understanding of the gene expression process, fine-tuning has become a meaningful tool for biosynthesis optimization. This study characterized several gene expression elements and constructed a multiple inducible system that responds to ten different small chemical inducers in halophile bacterium Halomonas bluephagenesis. Genome insertion of regulators was conducted for the purpose of gene cluster stabilization and regulatory plasmid simplification. Additionally, dynamic ranges of the multiple inducible systems were tuned by promoter sequence mutations to achieve diverse scopes for high-resolution gene expression control. The multiple inducible system was successfully employed to precisely control chromoprotein expression, lycopene and poly-3-hydroxybutyrate (PHB) biosynthesis, resulting in colorful bacterial pictures, optimized cell growth, lycopene and PHB accumulation. This study demonstrates a desirable approach for fine-tuning of rational and efficient gene expressions, displaying the significance for metabolic pathway optimization.
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Affiliation(s)
- Yueyuan Ma
- School of Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Jian-Wen Ye
- School of Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Yina Lin
- School of Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Xueqing Yi
- School of Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Xuan Wang
- School of Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Huan Wang
- School of Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Ruiyan Huang
- Garrison Forest School, Owings Mills, MD, 21117, USA
| | - Fuqing Wu
- School of Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Qiong Wu
- School of Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Xu Liu
- PhaBuilder Biotech Co. Ltd., Beijing, 101309, China
| | - Guo-Qiang Chen
- School of Life Sciences, Tsinghua University, Beijing, 100084, China; Center for Synthetic and Systems Biology, Tsinghua University, Beijing, 100084, China; MOE Key Laboratory for Industrial Biocatalysts, Dept Chemical Engineering, Tsinghua University, Beijing, 100084, China; Tsinghua-Peking Center for Life Sciences, Beijing, 100084, China.
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Zhou C, Yang G, Meng P, Qin W, Li Y, Lin Z, Hui W, Zhang H, Lu F. Identification and engineering of the aprE regulatory region and relevant regulatory proteins in Bacillus licheniformis 2709. Enzyme Microb Technol 2024; 172:110310. [PMID: 37925770 DOI: 10.1016/j.enzmictec.2023.110310] [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: 05/10/2023] [Revised: 08/01/2023] [Accepted: 08/27/2023] [Indexed: 11/07/2023]
Abstract
Bacillus licheniformis 2709 is the main industrial producer of alkaline protease (AprE), but its biosynthesis is strictly controlled by a highly sophisticated transcriptional network. In this study, the UP elements of aprE located 74-98, 98-119 and 140-340 bp upstream of the transcriptional start site (TSS) were identified, which presented obvious effects on the transcription of aprE. To further analyze the transcriptional mechanism, the specific proteins binding to the approximately 500-bp DNA sequences were subsequently captured by reverse-chromatin immunoprecipitation (reverse-ChIP) and DNA pull-down (DPD) assays, which captured the transcriptional factors CggR, FruR, and YhcZ. The study demonstrated that CggR, FruR and YhcZ had no significant effect on cell growth and aprE expression. Then, aprE expression was significantly enhanced by deleting a potential negative regulatory factor binding site in the genome. The AprE enzyme activity in shake flasks of the genomic mutant BL ∆1 was 47% higher than in the original strain, while the aprE transcription level increased 3.16 times. The protocol established in this study provides a valuable reference for the high-level production of proteins in other Bacillus species. At the same time, it will help reveal the molecular mechanism of the transcriptional regulatory network of aprE and provide important theoretical guidance for further enhancing the yield of AprE.
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Affiliation(s)
- Cuixia Zhou
- School of biology and brewing engineering, Taishan University, Taian 271018, PR China; Key laboratory of industrial fermentation microbiology, Ministry of education, College of biotechnology, Tianjin University of Science &Technology, Tianjin 300450, PR China
| | - Guangcheng Yang
- School of biology and brewing engineering, Taishan University, Taian 271018, PR China.
| | - Panpan Meng
- School of biology and brewing engineering, Taishan University, Taian 271018, PR China
| | - Weishuai Qin
- School of biology and brewing engineering, Taishan University, Taian 271018, PR China
| | - Yanyan Li
- School of biology and brewing engineering, Taishan University, Taian 271018, PR China
| | - Zhenxian Lin
- School of biology and brewing engineering, Taishan University, Taian 271018, PR China
| | - Wei Hui
- Key laboratory of industrial fermentation microbiology, Ministry of education, College of biotechnology, Tianjin University of Science &Technology, Tianjin 300450, PR China
| | - Huitu Zhang
- Key laboratory of industrial fermentation microbiology, Ministry of education, College of biotechnology, Tianjin University of Science &Technology, Tianjin 300450, PR China
| | - Fuping Lu
- Key laboratory of industrial fermentation microbiology, Ministry of education, College of biotechnology, Tianjin University of Science &Technology, Tianjin 300450, PR China.
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Wang Y, Tian YS, Gao JJ, Xu J, Li ZJ, Fu XY, Han HJ, Wang LJ, Zhang WH, Deng YD, Qian C, Zuo ZH, Wang B, Peng RH, Yao QH. Complete biodegradation of the oldest organic herbicide 2,4-Dichlorophenoxyacetic acid by engineering Escherichia coli. JOURNAL OF HAZARDOUS MATERIALS 2023; 451:131099. [PMID: 36868133 DOI: 10.1016/j.jhazmat.2023.131099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2022] [Revised: 02/23/2023] [Accepted: 02/25/2023] [Indexed: 06/18/2023]
Abstract
After nearly 80 years of extensive application, the oldest organic herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) has caused many problems of environmental pollution and ecological deterioration. Bioremediation is an ideal method for pollutant treatment. However, difficult screening and preparation of efficient degradation bacteria have largely hindered its application in 2,4-D remediation. We have created a novel engineering Escherichia coli with a reconstructed complete degradation pathway of 2,4-D to solve the problem of screening highly efficient degradation bacteria in this study. The results of fluorescence quantitative PCR demonstrated that all nine genes in the degradation pathway were successfully expressed in the engineered strain. The engineered strains can quickly and completely degrade 0.5 mM 2, 4-D within 6 h. Inspiring, the engineered strains grew with 2,4-D as the sole carbon source. By using the isotope tracing method, the metabolites of 2,4-D were found incorporated into the tricarboxylic acid cycle in the engineering strain. Scanning electron microscopy showed that 2,4-D had less damage on the engineered bacteria than the wild-type strain. Engineered strain can also rapidly and completely remedy 2,4-D pollution in natural water and soil. Assembling the metabolic pathways of pollutants through synthetic biology was an effective method to create pollutant-degrading bacteria for bioremediation.
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Affiliation(s)
- Yu Wang
- Shanghai Key laboratory of Agricultural Genetics and Breeding, Biotechnology Research Institute, Shanghai Academy of Agricultural Sciences, Shanghai, China
| | - Yong-Sheng Tian
- Shanghai Key laboratory of Agricultural Genetics and Breeding, Biotechnology Research Institute, Shanghai Academy of Agricultural Sciences, Shanghai, China
| | - Jian-Jie Gao
- Shanghai Key laboratory of Agricultural Genetics and Breeding, Biotechnology Research Institute, Shanghai Academy of Agricultural Sciences, Shanghai, China
| | - Jing Xu
- Shanghai Key laboratory of Agricultural Genetics and Breeding, Biotechnology Research Institute, Shanghai Academy of Agricultural Sciences, Shanghai, China
| | - Zhen-Jun Li
- Shanghai Key laboratory of Agricultural Genetics and Breeding, Biotechnology Research Institute, Shanghai Academy of Agricultural Sciences, Shanghai, China
| | - Xiao-Yan Fu
- Shanghai Key laboratory of Agricultural Genetics and Breeding, Biotechnology Research Institute, Shanghai Academy of Agricultural Sciences, Shanghai, China
| | - Hong-Juan Han
- Shanghai Key laboratory of Agricultural Genetics and Breeding, Biotechnology Research Institute, Shanghai Academy of Agricultural Sciences, Shanghai, China
| | - Li-Juan Wang
- Shanghai Key laboratory of Agricultural Genetics and Breeding, Biotechnology Research Institute, Shanghai Academy of Agricultural Sciences, Shanghai, China
| | - Wen-Hui Zhang
- Shanghai Key laboratory of Agricultural Genetics and Breeding, Biotechnology Research Institute, Shanghai Academy of Agricultural Sciences, Shanghai, China
| | - Yong-Dong Deng
- Shanghai Key laboratory of Agricultural Genetics and Breeding, Biotechnology Research Institute, Shanghai Academy of Agricultural Sciences, Shanghai, China
| | - Cen Qian
- Shanghai Key laboratory of Agricultural Genetics and Breeding, Biotechnology Research Institute, Shanghai Academy of Agricultural Sciences, Shanghai, China
| | - Zhi-Hao Zuo
- Shanghai Key laboratory of Agricultural Genetics and Breeding, Biotechnology Research Institute, Shanghai Academy of Agricultural Sciences, Shanghai, China
| | - Bo Wang
- Shanghai Key laboratory of Agricultural Genetics and Breeding, Biotechnology Research Institute, Shanghai Academy of Agricultural Sciences, Shanghai, China.
| | - Ri-He Peng
- Shanghai Key laboratory of Agricultural Genetics and Breeding, Biotechnology Research Institute, Shanghai Academy of Agricultural Sciences, Shanghai, China.
| | - Quan-Hong Yao
- Shanghai Key laboratory of Agricultural Genetics and Breeding, Biotechnology Research Institute, Shanghai Academy of Agricultural Sciences, Shanghai, China.
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4
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A Comparative Transcriptomic with UPLC-Q-Exactive MS Reveals Differences in Gene Expression and Components of Iridoid Biosynthesis in Various Parts of Gentiana macrophylla. Genes (Basel) 2022; 13:genes13122372. [PMID: 36553639 PMCID: PMC9778098 DOI: 10.3390/genes13122372] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Revised: 12/12/2022] [Accepted: 12/13/2022] [Indexed: 12/23/2022] Open
Abstract
Gentiana macrophylla Pall. (G. macrophylla)-a member of the family Gentianaceae-is a well-known traditional Chinese medical herb. Iridoids are the main active components of G. macrophylla, which has a wide range of pharmacological activities such as dispelling wind, eliminating dampness, clearing heat and asthenic fever, hepatoprotective and choleretic actions, and other medicinal effects. In this study, a total of 67,048 unigenes were obtained by transcriptomic sequencing analysis of G. macrophylla. A BLAST analysis showed that 48.21%, 33.66%, 46.32%, and 32.62% of unigenes were identified in the NR, Swiss-Prot, eggNOG, and KEGG databases, respectively. Twenty-five key enzymes were identified in the iridoid biosynthesis pathway. Most of the upregulated unigenes were enriched in flowers and leaves. The trustworthiness of the transcriptomic data was validated by real-time quantitative PCR (qRT-PCR). A total of 22 chemical constituents were identified by ultra-high performance liquid chromatography-quadrupole-electrostatic field Orbitrap mass spectrometry (UPLC-Q-Exactive MS), including 10 iridoids. A correlation analysis showed that the expression of 7-DLH and SLS was closely related to iridoids. The expression of 7-DLH and SLS was higher in flowers, indicating that flowers are important for iridoid biosynthesis in G. macrophylla.
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Chen WCW, Gaidukov L, Lai Y, Wu MR, Cao J, Gutbrod MJ, Choi GCG, Utomo RP, Chen YC, Wroblewska L, Kellis M, Zhang L, Weiss R, Lu TK. A synthetic transcription platform for programmable gene expression in mammalian cells. Nat Commun 2022; 13:6167. [PMID: 36257931 PMCID: PMC9579178 DOI: 10.1038/s41467-022-33287-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Accepted: 09/13/2022] [Indexed: 12/24/2022] Open
Abstract
Precise, scalable, and sustainable control of genetic and cellular activities in mammalian cells is key to developing precision therapeutics and smart biomanufacturing. Here we create a highly tunable, modular, versatile CRISPR-based synthetic transcription system for the programmable control of gene expression and cellular phenotypes in mammalian cells. Genetic circuits consisting of well-characterized libraries of guide RNAs, binding motifs of synthetic operators, transcriptional activators, and additional genetic regulatory elements express mammalian genes in a highly predictable and tunable manner. We demonstrate the programmable control of reporter genes episomally and chromosomally, with up to 25-fold more activity than seen with the EF1α promoter, in multiple cell types. We use these circuits to program the secretion of human monoclonal antibodies and to control T-cell effector function marked by interferon-γ production. Antibody titers and interferon-γ concentrations significantly correlate with synthetic promoter strengths, providing a platform for programming gene expression and cellular function in diverse applications.
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Affiliation(s)
- William C W Chen
- Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA.
- Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA.
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA.
- Cardiovascular Research Center, Massachusetts General Hospital, Boston, MA, 02114, USA.
- Division of Basic Biomedical Sciences, Sanford School of Medicine, University of South Dakota, Vermillion, SD, 57069, USA.
| | - Leonid Gaidukov
- Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Yong Lai
- Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Ming-Ru Wu
- Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- Dana-Farber Cancer Institute and Harvard Medical School, Boston, MA, 02215, USA
| | - Jicong Cao
- Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Michael J Gutbrod
- Computer Science and Artificial Intelligence Laboratory, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- Broad Institute of Massachusetts Institute of Technology and Harvard University, Cambridge, MA, 02139, USA
| | - Gigi C G Choi
- Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- Laboratory of Combinatorial Genetics and Synthetic Biology, School of Biomedical Sciences, The University of Hong Kong, Hong Kong, China
| | - Rachel P Utomo
- Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- Department of Biochemistry, Wellesley College, Wellesley, MA, 02481, USA
| | - Ying-Chou Chen
- Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taipei, Taiwan
| | | | - Manolis Kellis
- Computer Science and Artificial Intelligence Laboratory, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- Broad Institute of Massachusetts Institute of Technology and Harvard University, Cambridge, MA, 02139, USA
| | - Lin Zhang
- Pfizer Inc., Andover, MA, 01810, USA
| | - Ron Weiss
- Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Timothy K Lu
- Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA.
- Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA.
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA.
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6
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Deng YD, Wang LJ, Zhang WH, Xu J, Gao JJ, Wang B, Fu XY, Han HJ, Li ZJ, Wang Y, Tian YS, Peng RH, Yao QH. Construction of complete degradation pathway for nitrobenzene in Escherichia coli. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2022; 243:114016. [PMID: 36027713 DOI: 10.1016/j.ecoenv.2022.114016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2022] [Revised: 07/31/2022] [Accepted: 08/21/2022] [Indexed: 06/15/2023]
Abstract
Nitrobenzene is widely present in industrial wastewater and soil. Biodegradation has become an ideal method to remediate organic pollutants due to its low cost, high efficiency, and absence of secondary pollution. In the present study, 10 exogenous genes that can completely degrade nitrobenzene were introduced into Escherichia coli, and their successful expression in the strain was verified by fluorescence quantitative polymerase chain reaction and proteomic analysis. The results of the degradation experiment showed that the engineered strain could completely degrade 4 mM nitrobenzene within 8 h. The formation of intermediate metabolites was detected, and the final metabolites entered the E. coli tricarboxylic acid cycle smoothly. This process was discovered by isotope tracing method. Results indicated the integrality of the degradation pathway and the complete degradation of nitrobenzene. Finally, further experiments were conducted in soil to verify its degradation ability and showed that the engineered strain could also degrade 1 mM nitrobenzene within 10 h. In this study, engineered bacteria that can completely degrade nitrobenzene have been constructed successfully. The construction of remediation-engineered bacteria by synthetic biology laid the foundation for the industrial application of biological degradation of organic pollutants.
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Affiliation(s)
- Yong-Dong Deng
- Biotechnology Research Institute of Shanghai Academy of Agricultural Sciences, Shanghai Key Laboratory of Agricultural Genetics and Breeding, 2901, Beidi Road, Shanghai, China; Key Laboratory for Safety Assessment (Enviornment) of Agricultural Genetically Modified Organisms, Ministry of Agriculture and Rural Affairs, Shanghai, China
| | - Li-Juan Wang
- Biotechnology Research Institute of Shanghai Academy of Agricultural Sciences, Shanghai Key Laboratory of Agricultural Genetics and Breeding, 2901, Beidi Road, Shanghai, China; Key Laboratory for Safety Assessment (Enviornment) of Agricultural Genetically Modified Organisms, Ministry of Agriculture and Rural Affairs, Shanghai, China
| | - Wen-Hui Zhang
- Biotechnology Research Institute of Shanghai Academy of Agricultural Sciences, Shanghai Key Laboratory of Agricultural Genetics and Breeding, 2901, Beidi Road, Shanghai, China; Key Laboratory for Safety Assessment (Enviornment) of Agricultural Genetically Modified Organisms, Ministry of Agriculture and Rural Affairs, Shanghai, China
| | - Jing Xu
- Biotechnology Research Institute of Shanghai Academy of Agricultural Sciences, Shanghai Key Laboratory of Agricultural Genetics and Breeding, 2901, Beidi Road, Shanghai, China; Key Laboratory for Safety Assessment (Enviornment) of Agricultural Genetically Modified Organisms, Ministry of Agriculture and Rural Affairs, Shanghai, China
| | - Jian-Jie Gao
- Biotechnology Research Institute of Shanghai Academy of Agricultural Sciences, Shanghai Key Laboratory of Agricultural Genetics and Breeding, 2901, Beidi Road, Shanghai, China; Key Laboratory for Safety Assessment (Enviornment) of Agricultural Genetically Modified Organisms, Ministry of Agriculture and Rural Affairs, Shanghai, China
| | - Bo Wang
- Biotechnology Research Institute of Shanghai Academy of Agricultural Sciences, Shanghai Key Laboratory of Agricultural Genetics and Breeding, 2901, Beidi Road, Shanghai, China; Key Laboratory for Safety Assessment (Enviornment) of Agricultural Genetically Modified Organisms, Ministry of Agriculture and Rural Affairs, Shanghai, China
| | - Xiao-Yan Fu
- Biotechnology Research Institute of Shanghai Academy of Agricultural Sciences, Shanghai Key Laboratory of Agricultural Genetics and Breeding, 2901, Beidi Road, Shanghai, China; Key Laboratory for Safety Assessment (Enviornment) of Agricultural Genetically Modified Organisms, Ministry of Agriculture and Rural Affairs, Shanghai, China
| | - Hong-Juan Han
- Biotechnology Research Institute of Shanghai Academy of Agricultural Sciences, Shanghai Key Laboratory of Agricultural Genetics and Breeding, 2901, Beidi Road, Shanghai, China; Key Laboratory for Safety Assessment (Enviornment) of Agricultural Genetically Modified Organisms, Ministry of Agriculture and Rural Affairs, Shanghai, China
| | - Zhen-Jun Li
- Biotechnology Research Institute of Shanghai Academy of Agricultural Sciences, Shanghai Key Laboratory of Agricultural Genetics and Breeding, 2901, Beidi Road, Shanghai, China; Key Laboratory for Safety Assessment (Enviornment) of Agricultural Genetically Modified Organisms, Ministry of Agriculture and Rural Affairs, Shanghai, China
| | - Yu Wang
- Biotechnology Research Institute of Shanghai Academy of Agricultural Sciences, Shanghai Key Laboratory of Agricultural Genetics and Breeding, 2901, Beidi Road, Shanghai, China; Key Laboratory for Safety Assessment (Enviornment) of Agricultural Genetically Modified Organisms, Ministry of Agriculture and Rural Affairs, Shanghai, China
| | - Yong-Sheng Tian
- Biotechnology Research Institute of Shanghai Academy of Agricultural Sciences, Shanghai Key Laboratory of Agricultural Genetics and Breeding, 2901, Beidi Road, Shanghai, China; Key Laboratory for Safety Assessment (Enviornment) of Agricultural Genetically Modified Organisms, Ministry of Agriculture and Rural Affairs, Shanghai, China.
| | - Ri-He Peng
- Biotechnology Research Institute of Shanghai Academy of Agricultural Sciences, Shanghai Key Laboratory of Agricultural Genetics and Breeding, 2901, Beidi Road, Shanghai, China; Key Laboratory for Safety Assessment (Enviornment) of Agricultural Genetically Modified Organisms, Ministry of Agriculture and Rural Affairs, Shanghai, China.
| | - Quan-Hong Yao
- Biotechnology Research Institute of Shanghai Academy of Agricultural Sciences, Shanghai Key Laboratory of Agricultural Genetics and Breeding, 2901, Beidi Road, Shanghai, China; Key Laboratory for Safety Assessment (Enviornment) of Agricultural Genetically Modified Organisms, Ministry of Agriculture and Rural Affairs, Shanghai, China.
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7
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Zhang P, Gong JS, Qin J, Li H, Hou HJ, Zhang XM, Xu ZH, Shi JS. Phospholipids (PLs) know-how: exploring and exploiting phospholipase D for its industrial dissemination. Crit Rev Biotechnol 2021; 41:1257-1278. [PMID: 33985392 DOI: 10.1080/07388551.2021.1921690] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Revised: 12/26/2020] [Accepted: 02/24/2021] [Indexed: 10/21/2022]
Abstract
Owing to their numerous nutritional and bioactive functions, phospholipids (PLs), which are major components of biological membranes in all living organisms, have been widely applied as nutraceuticals, food supplements, and cosmetic ingredients. To date, PLs are extracted solely from soybean or egg yolk, despite the diverse market demands and high cost, owing to a tedious and inefficient manufacturing process. A microbial-based manufacturing process, specifically phospholipase D (PLD)-based biocatalysis and biotransformation process for PLs, has the potential to address several challenges associated with the soybean- or egg yolk-based supply chain. However, poor enzyme properties and inefficient microbial expression systems for PLD limit their wide industrial dissemination. Therefore, sourcing new enzyme variants with improved properties and developing advanced PLD expression systems are important. In the present review, we systematically summarize recent achievements and trends in the discovery, their structural properties, catalytic mechanisms, expression strategies for enhancing PLD production, and its multiple applications in the context of PLs. This review is expected to assist researchers to understand current advances in this field and provide insights for further molecular engineering efforts toward PLD-mediated bioprocessing.
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Affiliation(s)
- Peng Zhang
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Pharmaceutical Sciences, Jiangnan University, Wuxi, P. R. China
| | - Jin-Song Gong
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Pharmaceutical Sciences, Jiangnan University, Wuxi, P. R. China
| | - Jiufu Qin
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Lyngby, Denmark
| | - Hui Li
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Pharmaceutical Sciences, Jiangnan University, Wuxi, P. R. China
| | - Hai-Juan Hou
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Pharmaceutical Sciences, Jiangnan University, Wuxi, P. R. China
| | - Xiao-Mei Zhang
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Pharmaceutical Sciences, Jiangnan University, Wuxi, P. R. China
| | - Zheng-Hong Xu
- National Engineering Laboratory for Cereal Fermentation Technology, School of Biotechnology, Jiangnan University, Wuxi, P. R. China
- Jiangsu Provincial Research Center for Bioactive Product Processing Technology, Jiangnan University, Wuxi, P. R. China
| | - Jin-Song Shi
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Pharmaceutical Sciences, Jiangnan University, Wuxi, P. R. China
- Jiangsu Provincial Research Center for Bioactive Product Processing Technology, Jiangnan University, Wuxi, P. R. China
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8
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Zhou C, Yang G, Zhang L, Zhang H, Zhou H, Lu F. Construction of an alkaline protease overproducer strain based on Bacillus licheniformis 2709 using an integrative approach. Int J Biol Macromol 2021; 193:1449-1456. [PMID: 34742839 DOI: 10.1016/j.ijbiomac.2021.10.208] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Revised: 10/27/2021] [Accepted: 10/27/2021] [Indexed: 11/16/2022]
Abstract
Bacillus licheniformis 2709 is a potential cell factory for the production of alkaline protease AprE, which has important value in industrial application but still lacks sufficient production capacity. To address this problem, we investigated the effects of the secretory viscous materials on the synthesis of AprE, which might seriously affect the industrial fermentation. Furthermore, an iterative chromosomal integration strategy at various chromosomal loci was implemented to achieve stable high-level expression of AprE in B. licheniformis 2709. The host was genetically modified by disrupting the native pgs cluster controlling the biosynthesis of viscous poly-glutamic acid identified in the study by GC/MS, generating a mutant with significantly higher biomass and better bioreactor performance. We further enhanced the expression of alkaline protease by integrating two additional aprE expression cassettes into the genome, generating the integration mutant BL ∆UEP-3 with three aprE expression cassettes, whose AprE enzyme activity in shake flasks reached 25,736 ± 997 U/mL, which was 136% higher than that of the original strain, while the aprE transcription level increased 4.05 times. Thus, an AprE high-yielding strain with excellent fermentation traits was engineered, which was more suitable for bulk-production. Finally, the AprE titer was further increased in a 5-L fermenter, reaching 57,763 ± 1039 U/mL. In summary, genetic modification is an enabling technology for enhancing enzyme production by eliminating the unfavorable characteristics of the host and optimizing the expression of aprE through iterative chromosomal integration. We believe that the protocol developed in this study provides a valuable reference for chromosomal overexpression of proteins or bioactive molecules in other Bacillus species.
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Affiliation(s)
- Cuixia Zhou
- School of Biology and Brewing Engineering, Taishan University, Taian 271018, PR China; Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, College of Biotechnology, Tianjin University of Science &Technology, Tianjin 300450, PR China
| | - Guangcheng Yang
- School of Biology and Brewing Engineering, Taishan University, Taian 271018, PR China.
| | - Lei Zhang
- School of Biology and Brewing Engineering, Taishan University, Taian 271018, PR China
| | - Huitu Zhang
- Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, College of Biotechnology, Tianjin University of Science &Technology, Tianjin 300450, PR China
| | - Huiying Zhou
- Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, College of Biotechnology, Tianjin University of Science &Technology, Tianjin 300450, PR China
| | - Fuping Lu
- Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, College of Biotechnology, Tianjin University of Science &Technology, Tianjin 300450, PR China.
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9
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Tietze L, Lale R. Importance of the 5' regulatory region to bacterial synthetic biology applications. Microb Biotechnol 2021; 14:2291-2315. [PMID: 34171170 PMCID: PMC8601185 DOI: 10.1111/1751-7915.13868] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 06/03/2021] [Accepted: 06/04/2021] [Indexed: 01/02/2023] Open
Abstract
The field of synthetic biology is evolving at a fast pace. It is advancing beyond single-gene alterations in single hosts to the logical design of complex circuits and the development of integrated synthetic genomes. Recent breakthroughs in deep learning, which is increasingly used in de novo assembly of DNA components with predictable effects, are also aiding the discipline. Despite advances in computing, the field is still reliant on the availability of pre-characterized DNA parts, whether natural or synthetic, to regulate gene expression in bacteria and make valuable compounds. In this review, we discuss the different bacterial synthetic biology methodologies employed in the creation of 5' regulatory regions - promoters, untranslated regions and 5'-end of coding sequences. We summarize methodologies and discuss their significance for each of the functional DNA components, and highlight the key advances made in bacterial engineering by concentrating on their flaws and strengths. We end the review by outlining the issues that the discipline may face in the near future.
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Affiliation(s)
- Lisa Tietze
- PhotoSynLabDepartment of BiotechnologyFaculty of Natural SciencesNorwegian University of Science and TechnologyTrondheimN‐7491Norway
| | - Rahmi Lale
- PhotoSynLabDepartment of BiotechnologyFaculty of Natural SciencesNorwegian University of Science and TechnologyTrondheimN‐7491Norway
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10
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Wang B, Gao J, Xu J, Fu X, Han H, Li Z, Wang L, Zhang F, Tian Y, Peng R, Yao Q. Optimization and reconstruction of two new complete degradation pathways for 3-chlorocatechol and 4-chlorocatechol in Escherichia coli. JOURNAL OF HAZARDOUS MATERIALS 2021; 419:126428. [PMID: 34171665 DOI: 10.1016/j.jhazmat.2021.126428] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Revised: 05/11/2021] [Accepted: 06/16/2021] [Indexed: 06/13/2023]
Abstract
Chlorinated aromatic compounds are a serious environmental concern because of their widespread occurrence throughout the environment. Although several microorganisms have evolved to gain the ability to degrade chlorinated aromatic compounds and use them as carbon sources, they still cannot meet the diverse needs of pollution remediation. In this study, the degradation pathways for 3-chlorocatechol (3CC) and 4-chlorocatechol (4CC) were successfully reconstructed by the optimization, synthesis, and assembly of functional genes from different strains. The addition of a 13C-labeled substrate and functional analysis of different metabolic modules confirmed that the genetically engineered strains can metabolize chlorocatechol similar to naturally degrading strains. The strain containing either of these artificial pathways can degrade catechol, 3CC, and 4CC completely, although differences in the degradation efficiency may be noted. Proteomic analysis and scanning electron microscopy observation showed that 3CC and 4CC have toxic effects on Escherichia coli, but the engineered bacteria can significantly eliminate these inhibitory effects. As core metabolic pathways for the degradation of chloroaromatics, the two chlorocatechol degradation pathways constructed in this study can be used to construct pollution remediation-engineered bacteria, and the related technologies may be applied to construct complete degradation pathways for complex organic hazardous materials.
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Affiliation(s)
- Bo Wang
- Shanghai Key laboratory of Agricultural Genetics and Breeding, Agro-Biotechnology Research Institute, Shanghai Academy of Agricultural Sciences, Shanghai, PR China
| | - Jianjie Gao
- Shanghai Key laboratory of Agricultural Genetics and Breeding, Agro-Biotechnology Research Institute, Shanghai Academy of Agricultural Sciences, Shanghai, PR China
| | - Jing Xu
- Shanghai Key laboratory of Agricultural Genetics and Breeding, Agro-Biotechnology Research Institute, Shanghai Academy of Agricultural Sciences, Shanghai, PR China
| | - Xiaoyan Fu
- Shanghai Key laboratory of Agricultural Genetics and Breeding, Agro-Biotechnology Research Institute, Shanghai Academy of Agricultural Sciences, Shanghai, PR China
| | - Hongjuan Han
- Shanghai Key laboratory of Agricultural Genetics and Breeding, Agro-Biotechnology Research Institute, Shanghai Academy of Agricultural Sciences, Shanghai, PR China
| | - Zhenjun Li
- Shanghai Key laboratory of Agricultural Genetics and Breeding, Agro-Biotechnology Research Institute, Shanghai Academy of Agricultural Sciences, Shanghai, PR China
| | - Lijuan Wang
- Shanghai Key laboratory of Agricultural Genetics and Breeding, Agro-Biotechnology Research Institute, Shanghai Academy of Agricultural Sciences, Shanghai, PR China
| | - Fujian Zhang
- Shanghai Key laboratory of Agricultural Genetics and Breeding, Agro-Biotechnology Research Institute, Shanghai Academy of Agricultural Sciences, Shanghai, PR China
| | - Yongsheng Tian
- Shanghai Key laboratory of Agricultural Genetics and Breeding, Agro-Biotechnology Research Institute, Shanghai Academy of Agricultural Sciences, Shanghai, PR China.
| | - Rihe Peng
- Shanghai Key laboratory of Agricultural Genetics and Breeding, Agro-Biotechnology Research Institute, Shanghai Academy of Agricultural Sciences, Shanghai, PR China.
| | - Quanhong Yao
- Shanghai Key laboratory of Agricultural Genetics and Breeding, Agro-Biotechnology Research Institute, Shanghai Academy of Agricultural Sciences, Shanghai, PR China.
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11
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Biosensor-Based Multigene Pathway Optimization for Enhancing the Production of Glycolate. Appl Environ Microbiol 2021; 87:e0011321. [PMID: 33837017 DOI: 10.1128/aem.00113-21] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Glycolate is widely used in industry, especially in the fields of chemical cleaning, cosmetics, and medical materials, and has broad market prospects for the future. Recent advances in metabolic engineering and synthetic biology have significantly improved the titer and yield of glycolate. However, an expensive inducer was used in previous studies, which is not feasible for use in large-scale industrial fermentations. To constitutively biosynthesize glycolate, the expression level of each gene of the glycolate synthetic pathway needs to be systemically optimized. The main challenge of multigene pathway optimization is being able to select or screen the optimum strain from the randomly assembled library by an efficient high-throughput method within a short time. To overcome these challenges, we firstly established a glycolate-responsive biosensor and developed agar plate- and 48-well deep-well plate-scale high-throughput screening methods for the rapid screening of superior glycolate producers from a large library. A total of 22 gradient-strength promoter-5'-untranslated region (UTR) complexes were randomly cloned upstream of the genes of the glycolate synthetic pathway, generating a large random assembled library. After rounds of screening, the optimum strain was obtained from 6 × 105 transformants in a week, and it achieved a titer of 40.9 ± 3.7 g/liter glycolate in a 5-liter bioreactor. Furthermore, high expression levels of the enzymes YcdW and GltA were found to promote glycolate production, whereas AceA has no obvious impact on glycolate production. Overall, the glycolate biosensor-based pathway optimization strategy presented in this work provides a paradigm for other multigene pathway optimizations. IMPORTANCE The use of strong promoters, such as pTrc and T7, to control gene expression not only needs the addition of expensive inducers but also results in excessive protein expression that may result in unbalanced metabolic flux and the waste of cellular building blocks and energy. To balance the metabolic flux of glycolate biosynthesis, the expression level of each gene needs to be systemically optimized in a constitutive manner. However, the lack of high-throughput screening methods restricted glycolate synthetic pathway optimization. Our work firstly established a glycolate-response biosensor, and agar plate- and 48-well plate-scale high-throughput screening methods were then developed for the rapid screening of optimum pathways from a large library. Finally, we obtained a glycolate-producing strain with good biosynthetic performance, and the use of the expensive inducer isopropyl-β-d-thiogalactopyranoside (IPTG) was avoided, which broadens our understanding of the mechanism of glycolate synthesis.
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12
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Tominaga M, Nozaki K, Umeno D, Ishii J, Kondo A. Robust and flexible platform for directed evolution of yeast genetic switches. Nat Commun 2021; 12:1846. [PMID: 33758180 PMCID: PMC7988172 DOI: 10.1038/s41467-021-22134-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Accepted: 02/26/2021] [Indexed: 01/31/2023] Open
Abstract
A wide repertoire of genetic switches has accelerated prokaryotic synthetic biology, while eukaryotic synthetic biology has lagged in the model organism Saccharomyces cerevisiae. Eukaryotic genetic switches are larger and more complex than prokaryotic ones, complicating the rational design and evolution of them. Here, we present a robust workflow for the creation and evolution of yeast genetic switches. The selector system was designed so that both ON- and OFF-state selection of genetic switches is completed solely by liquid handling, and it enabled parallel screen/selection of different motifs with different selection conditions. Because selection threshold of both ON- and OFF-state selection can be flexibly tuned, the desired selection conditions can be rapidly pinned down for individual directed evolution experiments without a prior knowledge either on the library population. The system's utility was demonstrated using 20 independent directed evolution experiments, yielding genetic switches with elevated inducer sensitivities, inverted switching behaviours, sensory functions, and improved signal-to-noise ratio (>100-fold induction). The resulting yeast genetic switches were readily integrated, in a plug-and-play manner, into an AND-gated carotenoid biosynthesis pathway.
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Affiliation(s)
- Masahiro Tominaga
- grid.31432.370000 0001 1092 3077Graduate School of Science, Technology and Innovation, Kobe University, Kobe, Japan
| | - Kenta Nozaki
- grid.31432.370000 0001 1092 3077Graduate School of Science, Technology and Innovation, Kobe University, Kobe, Japan
| | - Daisuke Umeno
- grid.136304.30000 0004 0370 1101Department of Applied Chemistry and Biotechnology, Faculty of Engineering, Chiba University, Chiba, Japan
| | - Jun Ishii
- grid.31432.370000 0001 1092 3077Graduate School of Science, Technology and Innovation, Kobe University, Kobe, Japan ,grid.31432.370000 0001 1092 3077Engineering Biology Research Center, Kobe University, Kobe, Japan
| | - Akihiko Kondo
- grid.31432.370000 0001 1092 3077Graduate School of Science, Technology and Innovation, Kobe University, Kobe, Japan ,grid.31432.370000 0001 1092 3077Engineering Biology Research Center, Kobe University, Kobe, Japan ,grid.31432.370000 0001 1092 3077Department of Chemical Science and Engineering, Faculty of Engineering, Kobe University, Kobe, Japan ,grid.7597.c0000000094465255Center for Sustainable Resource Science, RIKEN, Yokohama, Japan
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13
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Duan Y, Zhai W, Liu W, Zhang X, Shi JS, Zhang X, Xu Z. Fine-Tuning Multi-Gene Clusters via Well-Characterized Gene Expression Regulatory Elements: Case Study of the Arginine Synthesis Pathway in C. glutamicum. ACS Synth Biol 2021; 10:38-48. [PMID: 33382575 DOI: 10.1021/acssynbio.0c00405] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Promoters and ribosome binding sites (RBSs) are routinely applied in gene expression regulation, but their orthogonality and combinatorial effects have not yet been systematically studied in Corynebacterium glutamicum. Here, 17 core promoters and 29 RBSs in C. glutamicum were characterized, which exhibited 470-fold and 430-fold in transcriptional and translational activity, respectively. By comparing the expression of two reporter genes regulated by multiple RBSs, the RBS efficacy showed significant dependence on the gene context, besides the RBSs' strength, reflecting the poor orthogonality of RBSs. Bicistron-modified RBS (referred as bc-RBS) was adapted to C. glutamicum, which improved RBS reliability. By coupling a series of promoters with RBSs/bc-RBSs, a much broader regulation range that spanned 4 orders of magnitude was observed compared with that of a sole element, and the contribution to gene expression of RBS was more than that of promoter. Finally, promoters and RBSs were applied as built-in elements to fine-tune the gene cluster in the arginine synthesis pathway in C. glutamicum. Compared with the original strain, more arginine (1.61-fold) or citrulline (2.35-fold) was accumulated in a 7 L bioreactor by strains with the gene expression regulation system rationally engineered. We demonstrated that, via combination of well-characterized gene elements, and overall consideration for both transcription and translation, the biosynthesis pathway can be effectively balanced, and the yield of a target metabolite can be further improved.
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Affiliation(s)
- Yanting Duan
- National Engineering Laboratory for Cereal Fermentation Technology, Key Laboratory of Industrial Biotechnology, Jiangnan University, 1800 Lihu Avenue, Wuxi 214122, China
- Biotechnology of Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Avenue, Wuxi 214122, China
| | - Weiji Zhai
- National Engineering Laboratory for Cereal Fermentation Technology, Key Laboratory of Industrial Biotechnology, Jiangnan University, 1800 Lihu Avenue, Wuxi 214122, China
- Biotechnology of Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Avenue, Wuxi 214122, China
| | - Weijia Liu
- Biotechnology of Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Avenue, Wuxi 214122, China
| | - Xiaomei Zhang
- School of Pharmaceutical Science, Jiangnan University, 1800 Lihu Avenue, Wuxi 214122, China
- Jiangsu Engineering Research Center for Bioactive Products Processing Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi 214122, China
| | - Jin-Song Shi
- School of Pharmaceutical Science, Jiangnan University, 1800 Lihu Avenue, Wuxi 214122, China
- Jiangsu Engineering Research Center for Bioactive Products Processing Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi 214122, China
| | - Xiaojuan Zhang
- National Engineering Laboratory for Cereal Fermentation Technology, Key Laboratory of Industrial Biotechnology, Jiangnan University, 1800 Lihu Avenue, Wuxi 214122, China
- Biotechnology of Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Avenue, Wuxi 214122, China
| | - Zhenghong Xu
- National Engineering Laboratory for Cereal Fermentation Technology, Key Laboratory of Industrial Biotechnology, Jiangnan University, 1800 Lihu Avenue, Wuxi 214122, China
- Biotechnology of Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Avenue, Wuxi 214122, China
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14
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She X, Lin Y, Liang R, Liu Z, Gao X, Ye J. RNA-Binding Motif Protein 38 as a Potential Biomarker and Therapeutic Target in Cancer. Onco Targets Ther 2020; 13:13225-13236. [PMID: 33380811 PMCID: PMC7769143 DOI: 10.2147/ott.s278755] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Accepted: 11/27/2020] [Indexed: 12/13/2022] Open
Abstract
RNA-binding proteins (RBPs) act as a key factor in gene regulation by governing RNA metabolism. They contribute to the expression and functions of most RNAs by binding to them and forming complexes. RNA-binding motif protein 38 (RBM38), a member of the RBP family, alters the stability and translation of targeted mRNAs to affect various biological processes, such as cell proliferation, cell cycle arrest, and myogenic differentiation. RBM38 contains a highly conserved RNA recognition motif (RRM) consisting of two subunits, RNP1 and RNP2, which specifically bind to RNAs. Recent studies have revealed that RBM38 regulates the mRNA stability of several tumor-related genes, such as p53, mdm2, p63, p73, p21, and c-Myc, by binding to their 3′ untranslated regions (3′ UTRs); thus, RBM38 modulates targeted gene expression and affects the biological processes of tumors. In addition, abnormal RBM38 expression in some malignant tumors and its correlation with prognosis have been documented in many studies, indicating its value for potential clinical applications. In this review, we present an overview of RBM38, specifically highlighting its relationship with tumor manifestation and development. A brief overview of the potential use of RBM38 in cancer therapy is also included to provide ideas for further research on RBM38.
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Affiliation(s)
- Xiaomin She
- Medical Oncology, Guangxi Medical University Cancer Hospital, Nanning, People's Republic of China
| | - Yan Lin
- Medical Oncology, Guangxi Medical University Cancer Hospital, Nanning, People's Republic of China
| | - Rong Liang
- Medical Oncology, Guangxi Medical University Cancer Hospital, Nanning, People's Republic of China
| | - Ziyu Liu
- Medical Oncology, Guangxi Medical University Cancer Hospital, Nanning, People's Republic of China
| | - Xing Gao
- Medical Oncology, Guangxi Medical University Cancer Hospital, Nanning, People's Republic of China
| | - Jiazhou Ye
- Medical Oncology, Guangxi Medical University Cancer Hospital, Nanning, People's Republic of China
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15
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Transcriptional control of gene expression in Pichia pastoris by manipulation of terminators. Appl Microbiol Biotechnol 2020; 104:7841-7851. [DOI: 10.1007/s00253-020-10785-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 07/03/2020] [Accepted: 07/13/2020] [Indexed: 12/11/2022]
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16
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Abstract
Single chain variable fragments (scFvs) are generated by joining together the variable heavy and light chain of a monoclonal antibody (mAb) via a peptide linker. They offer some advantages over the parental mAb such as low molecular weight, heterologous production, multimeric form, and multivalency. The scFvs were produced against more than 50 antigens till date using 10 different plant species as the expression system. There were considerable improvements in the expression and purification strategies of scFv in the last 24 years. With the growing demand of scFv in therapeutic and diagnostic fields, its biosynthesis needs to be increased. The easiness in development, maintenance, and multiplication of transgenic plants make them an attractive expression platform for scFv production. The review intends to provide comprehensive information about the use of plant expression system to produce scFv. The developments, advantages, pitfalls, and possible prospects of improvement for the exploitation of plants in the industrial level are discussed.
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Affiliation(s)
- Padikara Kutty Satheeshkumar
- Centre of Advanced Study in Botany, Institute of Science, Banaras Hindu University, Varanasi, UP, 221005, India.
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17
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Zhou C, Zhou H, Li D, Zhang H, Wang H, Lu F. Optimized expression and enhanced production of alkaline protease by genetically modified Bacillus licheniformis 2709. Microb Cell Fact 2020; 19:45. [PMID: 32093734 PMCID: PMC7041084 DOI: 10.1186/s12934-020-01307-2] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Accepted: 02/12/2020] [Indexed: 01/05/2023] Open
Abstract
BACKGROUND Bacillus licheniformis 2709 is extensively applied as a host for the high-level production of heterologous proteins, but Bacillus cells often possess unfavorable wild-type properties, such as production of viscous materials and foam during fermentation, which seriously influenced the application in industrial fermentation. How to develop it from a soil bacterium to a super-secreting cell factory harboring less undomesticated properties always plays vital role in industrial production. Besides, the optimal expression pattern of the inducible enzymes like alkaline protease has not been optimized by comparing the transcriptional efficiency of different plasmids and genomic integration sites in B. licheniformis. RESULT Bacillus licheniformis 2709 was genetically modified by disrupting the native lchAC genes related to foaming and the eps cluster encoding the extracellular mucopolysaccharide via a markerless genome-editing method. We further optimized the expression of the alkaline protease gene (aprE) by screening the most efficient expression system among different modular plasmids and genomic loci. The results indicated that genomic expression of aprE was superior to plasmid expression and finally the transcriptional level of aprE greatly increased 1.67-fold through host optimization and chromosomal integration in the vicinity of the origin of replication, while the enzyme activity significantly improved 62.19% compared with the wild-type alkaline protease-producing strain B. licheniformis. CONCLUSION We successfully engineered an AprE high-yielding strain free of undesirable properties and its fermentation traits could be applied to bulk-production by host genetic modification and expression optimization. In summary, host optimization is an enabling technology for improving enzyme production by eliminating the harmful traits of the host and optimizing expression patterns. We believe that these strategies can be applied to improve heterologous protein expression in other Bacillus species.
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Affiliation(s)
- Cuixia Zhou
- Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, College of Biotechnology, Tianjin University of Science & Technology, No. 29, 13th Road, Tianjin Economic-Technological Development Area, Tianjin 022, 300457, People's Republic of China
| | - Huiying Zhou
- Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, College of Biotechnology, Tianjin University of Science & Technology, No. 29, 13th Road, Tianjin Economic-Technological Development Area, Tianjin 022, 300457, People's Republic of China
| | - Dengke Li
- Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, College of Biotechnology, Tianjin University of Science & Technology, No. 29, 13th Road, Tianjin Economic-Technological Development Area, Tianjin 022, 300457, People's Republic of China
| | - Huitu Zhang
- Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, College of Biotechnology, Tianjin University of Science & Technology, No. 29, 13th Road, Tianjin Economic-Technological Development Area, Tianjin 022, 300457, People's Republic of China.
| | - Hongbin Wang
- Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, College of Biotechnology, Tianjin University of Science & Technology, No. 29, 13th Road, Tianjin Economic-Technological Development Area, Tianjin 022, 300457, People's Republic of China
| | - Fuping Lu
- Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, College of Biotechnology, Tianjin University of Science & Technology, No. 29, 13th Road, Tianjin Economic-Technological Development Area, Tianjin 022, 300457, People's Republic of China.
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18
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Castaño-Cerezo S, Fournié M, Urban P, Faulon JL, Truan G. Development of a Biosensor for Detection of Benzoic Acid Derivatives in Saccharomyces cerevisiae. Front Bioeng Biotechnol 2020; 7:372. [PMID: 31970152 PMCID: PMC6959289 DOI: 10.3389/fbioe.2019.00372] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Accepted: 11/13/2019] [Indexed: 01/14/2023] Open
Abstract
4-hydroxybenzoic acid (pHBA) is an important industrial precursor of muconic acid and liquid crystal polymers whose production is based on the petrochemical industry. In order to decrease our dependency on fossil fuels and improve sustainability, microbial engineering is a particularly appealing approach for replacing traditional chemical techniques. The optimization of microbial strains, however, is still highly constrained by the screening stage. Biosensors have helped to alleviate this problem by decreasing the screening time as well as enabling higher throughput. In this paper, we constructed a synthetic biosensor, named sBAD, consisting of a fusion of the pHBA-binding domain of HbaR from R. palustris, the LexA DNA binding domain at the N-terminus and the transactivation domain B112 at the C-terminus. The response of sBAD was tested in the presence of different benzoic acid derivatives, with cell fluorescence output measured by flow cytometry. The biosensor was found to be activated by the external addition of pHBA in the culture medium, in addition to other carboxylic acids including p-aminobenzoic acid (pABA), salicylic acid, anthranilic acid, aspirin, and benzoic acid. Furthermore, we were able to show that this biosensor could detect the in vivo production of pHBA in a genetically modified yeast strain. A good linearity was observed between the biosensor fluorescence and pHBA concentration. Thus, this biosensor would be well-suited as a high throughput screening tool to produce, via metabolic engineering, benzoic acid derivatives.
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Affiliation(s)
| | - Mathieu Fournié
- TBI, Université de Toulouse, CNRS, INRA, INSA, Toulouse, France
| | - Philippe Urban
- TBI, Université de Toulouse, CNRS, INRA, INSA, Toulouse, France
| | - Jean-Loup Faulon
- Micalis Institute, INRA, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France.,Chemistry School, Manchester Institute of Biotechnology, The University of Manchester, Manchester, United Kingdom
| | - Gilles Truan
- TBI, Université de Toulouse, CNRS, INRA, INSA, Toulouse, France
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19
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De Nijs Y, De Maeseneire SL, Soetaert WK. 5' untranslated regions: the next regulatory sequence in yeast synthetic biology. Biol Rev Camb Philos Soc 2019; 95:517-529. [PMID: 31863552 DOI: 10.1111/brv.12575] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Revised: 11/08/2019] [Accepted: 11/28/2019] [Indexed: 01/10/2023]
Abstract
When developing industrial biotechnology processes, Saccharomyces cerevisiae (baker's yeast or brewer's yeast) is a popular choice as a microbial host. Many tools have been developed in the fields of synthetic biology and metabolic engineering to introduce heterologous pathways and tune their expression in yeast. Such tools mainly focus on controlling transcription, whereas post-transcriptional regulation is often overlooked. Herein we discuss regulatory elements found in the 5' untranslated region (UTR) and their influence on protein synthesis. We provide not only an overall picture, but also a set of design rules on how to engineer a 5' UTR. The reader is also referred to currently available models that allow gene expression to be tuned predictably using different 5' UTRs.
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Affiliation(s)
- Yatti De Nijs
- Faculty of Bioscience Engineering, Centre for Industrial Biotechnology and Biocatalysis (InBio.be), Department Biotechnology, Ghent University, Coupure Links 653, 9000, Ghent, Belgium
| | - Sofie L De Maeseneire
- Faculty of Bioscience Engineering, Centre for Industrial Biotechnology and Biocatalysis (InBio.be), Department Biotechnology, Ghent University, Coupure Links 653, 9000, Ghent, Belgium
| | - Wim K Soetaert
- Faculty of Bioscience Engineering, Centre for Industrial Biotechnology and Biocatalysis (InBio.be), Department Biotechnology, Ghent University, Coupure Links 653, 9000, Ghent, Belgium
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20
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Rantasalo A, Landowski CP, Kuivanen J, Korppoo A, Reuter L, Koivistoinen O, Valkonen M, Penttilä M, Jäntti J, Mojzita D. A universal gene expression system for fungi. Nucleic Acids Res 2019; 46:e111. [PMID: 29924368 PMCID: PMC6182139 DOI: 10.1093/nar/gky558] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Accepted: 06/07/2018] [Indexed: 12/02/2022] Open
Abstract
Biotechnological production of fuels, chemicals and proteins is dependent on efficient production systems, typically genetically engineered microorganisms. New genome editing methods are making it increasingly easy to introduce new genes and functionalities in a broad range of organisms. However, engineering of all these organisms is hampered by the lack of suitable gene expression tools. Here, we describe a synthetic expression system (SES) that is functional in a broad spectrum of fungal species without the need for host-dependent optimization. The SES consists of two expression cassettes, the first providing a weak, but constitutive level of a synthetic transcription factor (sTF), and the second enabling strong, at will tunable expression of the target gene via an sTF-dependent promoter. We validated the SES functionality in six yeast and two filamentous fungi species in which high (levels beyond organism-specific promoters) as well as adjustable expression levels of heterologous and native genes was demonstrated. The SES is an unprecedentedly broadly functional gene expression regulation method that enables significantly improved engineering of fungi. Importantly, the SES system makes it possible to take in use novel eukaryotic microbes for basic research and various biotechnological applications.
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Affiliation(s)
- Anssi Rantasalo
- VTT Technical Research Centre of Finland, Espoo, P.O. Box 1000, FI-02044 VTT, Finland
| | | | - Joosu Kuivanen
- VTT Technical Research Centre of Finland, Espoo, P.O. Box 1000, FI-02044 VTT, Finland
| | - Annakarin Korppoo
- VTT Technical Research Centre of Finland, Espoo, P.O. Box 1000, FI-02044 VTT, Finland
| | - Lauri Reuter
- VTT Technical Research Centre of Finland, Espoo, P.O. Box 1000, FI-02044 VTT, Finland
| | - Outi Koivistoinen
- VTT Technical Research Centre of Finland, Espoo, P.O. Box 1000, FI-02044 VTT, Finland
| | - Mari Valkonen
- VTT Technical Research Centre of Finland, Espoo, P.O. Box 1000, FI-02044 VTT, Finland
| | - Merja Penttilä
- VTT Technical Research Centre of Finland, Espoo, P.O. Box 1000, FI-02044 VTT, Finland
| | - Jussi Jäntti
- VTT Technical Research Centre of Finland, Espoo, P.O. Box 1000, FI-02044 VTT, Finland
| | - Dominik Mojzita
- VTT Technical Research Centre of Finland, Espoo, P.O. Box 1000, FI-02044 VTT, Finland
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21
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Presnell KV, Flexer-Harrison M, Alper HS. Design and synthesis of synthetic UP elements for modulation of gene expression in Escherichia coli. Synth Syst Biotechnol 2019; 4:99-106. [PMID: 31080900 PMCID: PMC6501063 DOI: 10.1016/j.synbio.2019.04.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Revised: 04/10/2019] [Accepted: 04/11/2019] [Indexed: 11/29/2022] Open
Abstract
Metabolic engineering requires fine-tuned gene expression for most pathway optimization applications. To develop a suitable suite of promoters, traditional bacterial promoter engineering efforts have focused on modifications to the core region, especially the −10 and −35 regions, of native promoters. Here, we demonstrate an alternate, unexplored route of promoter engineering through randomization of the UP element of the promoter—a region that contacts the alpha subunit carboxy-terminal domain instead of the sigma subunit of the RNA polymerase holoenzyme. Through this work, we identify five novel UP element sequences through library-based searches in Escherichia coli. The resulting elements were used to activate the E. coli core promoter, rrnD promoter, to levels on par and higher than the prevalent strong bacterial promoter, OXB15. These relative levels of expression activation were transferrable when applied upstream of alternate core promoter sequences, including rrnA and rrnH. This work thus presents and validates a novel strategy for bacterial promoter engineering with transferability across varying core promoters and potential for transferability across bacterial species.
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Affiliation(s)
- Kristin V Presnell
- McKetta Department of Chemical Engineering, The University of Texas at Austin, 200 E Dean Keeton St. Stop C0400, Austin, TX, 78712, USA
| | - Madeleine Flexer-Harrison
- Institute for Cellular and Molecular Biology, The University of Texas at Austin, 2500 Speedway Avenue, Austin, TX, 78712, USA
| | - Hal S Alper
- McKetta Department of Chemical Engineering, The University of Texas at Austin, 200 E Dean Keeton St. Stop C0400, Austin, TX, 78712, USA.,Institute for Cellular and Molecular Biology, The University of Texas at Austin, 2500 Speedway Avenue, Austin, TX, 78712, USA
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Xie P. Current Control Method in Doubly Fed Induction Generator Under Low Switching Frequency. JOURNAL OF ADVANCED COMPUTATIONAL INTELLIGENCE AND INTELLIGENT INFORMATICS 2018. [DOI: 10.20965/jaciii.2018.p1109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The present current control method in doubly fed induction generator cannot realize the segmented grid-connected current control, it’s hard to effectively control the current in doubly fed induction generator. Therefore, a current control method in doubly fed induction generator under low switching frequency is proposed in this paper. Which means to build a mathematical model of the doubly fed induction generator under low switching frequency to analyze the parameters of doubly fed induction generator filter. Then the parameter values of the filter can be obtained. The current in generator can be predicted by adopting the double-sampling predict method. And the current control in generator can be improved according to dead beat control. Then the on-line identification of current parameters by least square method is needed to finish the current control method in doubly fed induction generator under low switching frequency. The experimental results show that the proposed method realized the segmented grid-connected current control in doubly fed induction generator.
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23
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Advances and prospects of Bacillus subtilis cellular factories: From rational design to industrial applications. Metab Eng 2018; 50:109-121. [DOI: 10.1016/j.ymben.2018.05.006] [Citation(s) in RCA: 115] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2017] [Revised: 05/02/2018] [Accepted: 05/10/2018] [Indexed: 01/29/2023]
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24
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Metabolic engineering for the production of chitooligosaccharides: advances and perspectives. Emerg Top Life Sci 2018; 2:377-388. [DOI: 10.1042/etls20180009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2018] [Revised: 08/06/2018] [Accepted: 08/07/2018] [Indexed: 11/17/2022]
Abstract
Chitin oligosaccharides (CTOs) and its related compounds chitosan oligosaccharides (CSOs), collectively known as chitooligosaccharides (COs), exhibit numerous biological activities in applications in the nutraceutical, cosmetics, agriculture, and pharmaceutical industries. COs are currently produced by acid hydrolysis of chitin or chitosan, or enzymatic techniques with uncontrollable polymerization. Microbial fermentation by recombinant Escherichia coli, as an alternative method for the production of COs, shows new potential because it can produce a well-defined COs mixture and is an environmentally friendly process. In addition, Bacillus subtilis, a nonpathogenic, endotoxin-free, GRAS status bacterium, presents a new opportunity as a platform to produce COs. Here, we review the applications of COs and differences between CTOs and CSOs, summarize the current preparation approaches of COs, and discuss the future research potentials and challenges in the production of well-defined COs in B. subtilis by metabolic engineering.
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25
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Cui W, Suo F, Cheng J, Han L, Hao W, Guo J, Zhou Z. Stepwise modifications of genetic parts reinforce the secretory production of nattokinase in Bacillus subtilis. Microb Biotechnol 2018; 11:930-942. [PMID: 29984489 PMCID: PMC6116739 DOI: 10.1111/1751-7915.13298] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Revised: 06/20/2018] [Accepted: 06/21/2018] [Indexed: 12/27/2022] Open
Abstract
Nattokinase (NK) is an important serine‐protease with direct fibrinolytic activity involving the prevention of cardiovascular disease as an antithrombotic agent. Dozens of studies have focused on the characterization of intrinsic novel promoters and signal peptides to the secretory production of recombinant proteins in Bacillus subtilis. However, intrinsic genetic elements have several drawbacks, which cannot mediate the production of NK to the desired level. In this study, the genetic elements, which were used to overproduce the recombinant secretory NK, were rationally modified in B. subtilis in a stepwise manner. The first step was to select a suitable signal peptide for the highly efficient secretion of NK. By comparison of the secretory levels mediated by two different signal peptides, which were encoded by the genes of a minor extracellular protease epr (SPepr) and cell‐wall associated protease wapA (SPwapA), respectively, SPwapA was verified as the superior secretory element. Second, P04, which was a synthetic promoter screened from an array of mutants based on the promoter cloned from the operon of a quorum‐sensing associated gene srfA (PsrfA), was paired to SPwapA. The secretory level of NK was obviously augmented by the combination of these two genetic elements. Third, the cis‐acting element CodY‐binding sequence positioned at the 5′UTR was deleted (yielding P08), and thus the secretory level was significantly elevated. The activity of NK, which was defined as fibrinolytic units (FU), reached to a level of 270 FU ml−1. Finally, the superior genetic element composed of P08 and SPwapA was utilized to overproduce NK in the host B. subtilis WB800, which was able to produce the secretory NK at 292 FU ml−1. The strategy established in this study can not only be used to overproduce NK in B. subtilis but also might be a promising pipeline to modify the genetic element for the synthetic secretory system.
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Affiliation(s)
- Wenjing Cui
- School of Biotechnology, Key Laboratory of Industrial Biotechnology (Ministry of Education), Jiangnan University, Wuxi, Jiangsu, 214122, China
| | - Feiya Suo
- School of Biotechnology, Key Laboratory of Industrial Biotechnology (Ministry of Education), Jiangnan University, Wuxi, Jiangsu, 214122, China
| | - Jintao Cheng
- School of Biotechnology, Key Laboratory of Industrial Biotechnology (Ministry of Education), Jiangnan University, Wuxi, Jiangsu, 214122, China
| | - Laichuang Han
- School of Biotechnology, Key Laboratory of Industrial Biotechnology (Ministry of Education), Jiangnan University, Wuxi, Jiangsu, 214122, China
| | - Wenliang Hao
- School of Biotechnology, Key Laboratory of Industrial Biotechnology (Ministry of Education), Jiangnan University, Wuxi, Jiangsu, 214122, China
| | - Junling Guo
- School of Biotechnology, Key Laboratory of Industrial Biotechnology (Ministry of Education), Jiangnan University, Wuxi, Jiangsu, 214122, China
| | - Zhemin Zhou
- School of Biotechnology, Key Laboratory of Industrial Biotechnology (Ministry of Education), Jiangnan University, Wuxi, Jiangsu, 214122, China
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26
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Rantasalo A, Kuivanen J, Penttilä M, Jäntti J, Mojzita D. Synthetic Toolkit for Complex Genetic Circuit Engineering in Saccharomyces cerevisiae. ACS Synth Biol 2018; 7:1573-1587. [PMID: 29750501 PMCID: PMC6150731 DOI: 10.1021/acssynbio.8b00076] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Sustainable production of chemicals, materials, and pharmaceuticals is increasingly performed by genetically engineered cell factories. Engineering of complex metabolic routes or cell behavior control systems requires robust and predictable gene expression tools. In this challenging task, orthogonality is a fundamental prerequisite for such tools. In this study, we developed and characterized in depth a comprehensive gene expression toolkit that allows accurate control of gene expression in Saccharomyces cerevisiae without marked interference with native cellular regulation. The toolkit comprises a set of transcription factors, designed to function as synthetic activators or repressors, and transcription-factor-dependent promoters, which together provide a broad expression range surpassing, at high end, the strongest native promoters. Modularity of the developed tools is demonstrated by establishing a novel bistable genetic circuit with robust performance to control a heterologous metabolic pathway and enabling on-demand switching between two alternative metabolic branches.
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Affiliation(s)
- Anssi Rantasalo
- VTT Technical Research Centre of Finland Ltd., P.O. Box 1000, FI-02044 VTT Espoo, Finland
| | - Joosu Kuivanen
- VTT Technical Research Centre of Finland Ltd., P.O. Box 1000, FI-02044 VTT Espoo, Finland
| | - Merja Penttilä
- VTT Technical Research Centre of Finland Ltd., P.O. Box 1000, FI-02044 VTT Espoo, Finland
| | - Jussi Jäntti
- VTT Technical Research Centre of Finland Ltd., P.O. Box 1000, FI-02044 VTT Espoo, Finland
| | - Dominik Mojzita
- VTT Technical Research Centre of Finland Ltd., P.O. Box 1000, FI-02044 VTT Espoo, Finland
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27
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Garcia-Ruiz E, HamediRad M, Zhao H. Pathway Design, Engineering, and Optimization. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2018; 162:77-116. [PMID: 27629378 DOI: 10.1007/10_2016_12] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
The microbial metabolic versatility found in nature has inspired scientists to create microorganisms capable of producing value-added compounds. Many endeavors have been made to transfer and/or combine pathways, existing or even engineered enzymes with new function to tractable microorganisms to generate new metabolic routes for drug, biofuel, and specialty chemical production. However, the success of these pathways can be impeded by different complications from an inherent failure of the pathway to cell perturbations. Pursuing ways to overcome these shortcomings, a wide variety of strategies have been developed. This chapter will review the computational algorithms and experimental tools used to design efficient metabolic routes, and construct and optimize biochemical pathways to produce chemicals of high interest.
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Affiliation(s)
- Eva Garcia-Ruiz
- Department of Chemical and Biomolecular Engineering, Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Mohammad HamediRad
- Department of Chemical and Biomolecular Engineering, Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Huimin Zhao
- Department of Chemical and Biomolecular Engineering, Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.
- Departments of Chemistry, Biochemistry, and Bioengineering, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.
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28
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Wang X, He Q, Yang Y, Wang J, Haning K, Hu Y, Wu B, He M, Zhang Y, Bao J, Contreras LM, Yang S. Advances and prospects in metabolic engineering of Zymomonas mobilis. Metab Eng 2018; 50:57-73. [PMID: 29627506 DOI: 10.1016/j.ymben.2018.04.001] [Citation(s) in RCA: 76] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2018] [Revised: 03/31/2018] [Accepted: 04/01/2018] [Indexed: 12/22/2022]
Abstract
Biorefinery of biomass-based biofuels and biochemicals by microorganisms is a competitive alternative of traditional petroleum refineries. Zymomonas mobilis is a natural ethanologen with many desirable characteristics, which makes it an ideal industrial microbial biocatalyst for commercial production of desirable bioproducts through metabolic engineering. In this review, we summarize the metabolic engineering progress achieved in Z. mobilis to expand its substrate and product ranges as well as to enhance its robustness against stressful conditions such as inhibitory compounds within the lignocellulosic hydrolysates and slurries. We also discuss a few metabolic engineering strategies that can be applied in Z. mobilis to further develop it as a robust workhorse for economic lignocellulosic bioproducts. In addition, we briefly review the progress of metabolic engineering in Z. mobilis related to the classical synthetic biology cycle of "Design-Build-Test-Learn", as well as the progress and potential to develop Z. mobilis as a model chassis for biorefinery practices in the synthetic biology era.
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Affiliation(s)
- Xia Wang
- Hubei Collaborative Innovation Center for Green Transformation of Bio-resources, Environmental Microbial Technology Center of Hubei Province, Hubei Key Laboratory of Industrial Biotechnology, College of Life Sciences, Hubei University, Wuhan 430062, China.
| | - Qiaoning He
- Hubei Collaborative Innovation Center for Green Transformation of Bio-resources, Environmental Microbial Technology Center of Hubei Province, Hubei Key Laboratory of Industrial Biotechnology, College of Life Sciences, Hubei University, Wuhan 430062, China.
| | - Yongfu Yang
- Hubei Collaborative Innovation Center for Green Transformation of Bio-resources, Environmental Microbial Technology Center of Hubei Province, Hubei Key Laboratory of Industrial Biotechnology, College of Life Sciences, Hubei University, Wuhan 430062, China.
| | - Jingwen Wang
- Hubei Collaborative Innovation Center for Green Transformation of Bio-resources, Environmental Microbial Technology Center of Hubei Province, Hubei Key Laboratory of Industrial Biotechnology, College of Life Sciences, Hubei University, Wuhan 430062, China.
| | - Katie Haning
- Institute for Cellular and Molecular Biology, Department of Chemical Engineering, Cockrell School of Engineering, University of Texas at Austin, Austin, TX, United States.
| | - Yun Hu
- Hubei Collaborative Innovation Center for Green Transformation of Bio-resources, Environmental Microbial Technology Center of Hubei Province, Hubei Key Laboratory of Industrial Biotechnology, College of Life Sciences, Hubei University, Wuhan 430062, China.
| | - Bo Wu
- Key Laboratory of Development and Application of Rural Renewable Energy, Biomass Energy Technology Research Centre, Biogas Institute of Ministry of Agriculture, South Renmin Road, Chengdu 610041, China.
| | - Mingxiong He
- Key Laboratory of Development and Application of Rural Renewable Energy, Biomass Energy Technology Research Centre, Biogas Institute of Ministry of Agriculture, South Renmin Road, Chengdu 610041, China.
| | - Yaoping Zhang
- DOE-Great Lakes Bioenergy Research Center (GLBRC), University of Wisconsin-Madison, Madison, WI, United States.
| | - Jie Bao
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China.
| | - Lydia M Contreras
- Institute for Cellular and Molecular Biology, Department of Chemical Engineering, Cockrell School of Engineering, University of Texas at Austin, Austin, TX, United States.
| | - Shihui Yang
- Hubei Collaborative Innovation Center for Green Transformation of Bio-resources, Environmental Microbial Technology Center of Hubei Province, Hubei Key Laboratory of Industrial Biotechnology, College of Life Sciences, Hubei University, Wuhan 430062, China.
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29
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You S, Yin Q, Zhang J, Zhang C, Qi W, Gao L, Tao Z, Su R, He Z. Utilization of biodiesel by-product as substrate for high-production of β-farnesene via relatively balanced mevalonate pathway in Escherichia coli. BIORESOURCE TECHNOLOGY 2017; 243:228-236. [PMID: 28672185 DOI: 10.1016/j.biortech.2017.06.058] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2017] [Revised: 06/09/2017] [Accepted: 06/10/2017] [Indexed: 05/02/2023]
Abstract
Farnesene has been identified as suitable jet fuel substitutes and metabolic engineering for microbial production of farnesene is an alternative and attractive route. In this study, due to accumulation of toxic intermediate isopentenyl pyrophosphate (IPP), an engineered Escherichia coli strain harboring heterologous mevalonate pathway produced only 4.11mg/L β-farnesene. Through higher-level expression of isopentenyl diphosphate isomerase and farnesyl diphosphate synthase to minimize the accumulated IPP, another engineered strain with relatively balanced mevalonate pathway was constructed and had the highest production of β-farnesene to date (8.74g/L) by Escherichia coli in a lab bioreactor. Furthermore, this is the first report on utilization of biodiesel by-product (simple purification) as substrate for high-production of β-farnesene by the engineered strain optimized and β-farnesene concentration reached 2.83g/L in a lab bioreactor. Therefore, the engineered strain optimized could be used as a platform host for high-production of other terpenoids using biodiesel by-product as substrate.
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Affiliation(s)
- Shengping You
- Chemical Engineering Research Center, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, PR China
| | - Qingdian Yin
- Chemical Engineering Research Center, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, PR China
| | - Jianye Zhang
- Chemical Engineering Research Center, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, PR China
| | - Chengyu Zhang
- Chemical Engineering Research Center, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, PR China
| | - Wei Qi
- Chemical Engineering Research Center, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, PR China; State Key Laboratory of Chemical Engineering, Tianjin University, Tianjin 300072, PR China; Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300072, PR China; Tianjin Key Laboratory of Membrane Science and Desalination Technology, Tianjin University, Tianjin 300072, PR China.
| | - Lan Gao
- SINOPEC CORP., Research Institute of Petroleum Processing (RIPP), Beijing 100083, PR China
| | - Zhiping Tao
- SINOPEC CORP., Research Institute of Petroleum Processing (RIPP), Beijing 100083, PR China
| | - Rongxin Su
- Chemical Engineering Research Center, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, PR China; State Key Laboratory of Chemical Engineering, Tianjin University, Tianjin 300072, PR China; Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300072, PR China; Tianjin Key Laboratory of Membrane Science and Desalination Technology, Tianjin University, Tianjin 300072, PR China
| | - Zhimin He
- Chemical Engineering Research Center, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, PR China; State Key Laboratory of Chemical Engineering, Tianjin University, Tianjin 300072, PR China
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30
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Tunnicliffe RB, Lockhart-Cairns MP, Levy C, Mould AP, Jowitt TA, Sito H, Baldock C, Sandri-Goldin RM, Golovanov AP. The herpes viral transcription factor ICP4 forms a novel DNA recognition complex. Nucleic Acids Res 2017; 45:8064-8078. [PMID: 28505309 PMCID: PMC5737704 DOI: 10.1093/nar/gkx419] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Accepted: 05/03/2017] [Indexed: 11/13/2022] Open
Abstract
The transcription factor ICP4 from herpes simplex virus has a central role in regulating the gene expression cascade which controls viral infection. Here we present the crystal structure of the functionally essential ICP4 DNA binding domain in complex with a segment from its own promoter, revealing a novel homo-dimeric fold. We also studied the complex in solution by small angle X-Ray scattering, nuclear magnetic resonance and surface-plasmon resonance which indicated that, in addition to the globular domain, a flanking intrinsically disordered region also recognizes DNA. Together the data provides a rationale for the bi-partite nature of the ICP4 DNA recognition consensus sequence as the globular and disordered regions bind synergistically to adjacent DNA motifs. Therefore in common with its eukaryotic host, the viral transcription factor ICP4 utilizes disordered regions to enhance the affinity and tune the specificity of DNA interactions in tandem with a globular domain.
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Affiliation(s)
- Richard B Tunnicliffe
- Manchester Institute of Biotechnology, School of Chemistry, Faculty of Science and Engineering, The University of Manchester, Manchester M1 7DN, UK
| | - Michael P Lockhart-Cairns
- Wellcome Trust Centre for Cell-Matrix Research, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, M13 9PT, UK.,Diamond Light Source, Harwell Science and Innovation Campus, Fermi Ave, Didcot OX11 0QX, UK
| | - Colin Levy
- Manchester Institute of Biotechnology, School of Chemistry, Faculty of Science and Engineering, The University of Manchester, Manchester M1 7DN, UK
| | - A Paul Mould
- Biomolecular Analysis Core Facility, Faculty of Biology, Medicine and Health, University of Manchester, M13 9PT, UK
| | - Thomas A Jowitt
- Biomolecular Analysis Core Facility, Faculty of Biology, Medicine and Health, University of Manchester, M13 9PT, UK
| | - Hilary Sito
- Manchester Institute of Biotechnology, School of Chemistry, Faculty of Science and Engineering, The University of Manchester, Manchester M1 7DN, UK
| | - Clair Baldock
- Wellcome Trust Centre for Cell-Matrix Research, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, M13 9PT, UK
| | - Rozanne M Sandri-Goldin
- Department of Microbiology and Molecular Genetics, School of Medicine, University of California, Irvine, CA 92697-4025, USA
| | - Alexander P Golovanov
- Manchester Institute of Biotechnology, School of Chemistry, Faculty of Science and Engineering, The University of Manchester, Manchester M1 7DN, UK
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31
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Han L, Suo F, Jiang C, Gu J, Li N, Zhang N, Cui W, Zhou Z. Fabrication and characterization of a robust and strong bacterial promoter from a semi-rationally engineered promoter library in Bacillus subtilis. Process Biochem 2017. [DOI: 10.1016/j.procbio.2017.06.024] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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32
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Gao M, Cao M, Suástegui M, Walker J, Rodriguez Quiroz N, Wu Y, Tribby D, Okerlund A, Stanley L, Shanks JV, Shao Z. Innovating a Nonconventional Yeast Platform for Producing Shikimate as the Building Block of High-Value Aromatics. ACS Synth Biol 2017; 6:29-38. [PMID: 27600996 DOI: 10.1021/acssynbio.6b00132] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The shikimate pathway serves an essential role in many organisms. Not only are the three aromatic amino acids synthesized through this pathway, but many secondary metabolites also derive from it. Decades of effort have been invested into engineering Saccharomyces cerevisiae to produce shikimate and its derivatives. In addition to the ability to express cytochrome P450, S. cerevisiae is generally recognized as safe for producing compounds with nutraceutical and pharmaceutical applications. However, the intrinsically complicated regulations involved in central metabolism and the low precursor availability in S. cerevisiae has limited production levels. Here we report the development of a new platform based on Scheffersomyces stipitis, whose superior xylose utilization efficiency makes it particularly suited to produce the shikimate group of compounds. Shikimate was produced at 3.11 g/L, representing the highest level among shikimate pathway products in yeasts. Our work represents a new exploration toward expanding the current collection of microbial factories.
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Affiliation(s)
- Meirong Gao
- Department of Chemical and Biological
Engineering, ‡NSF Engineering Research Center
for Biorenewable Chemicals (CBiRC), §Department of Chemistry, ∥Interdepartmental Microbiology
Program, Iowa State University, Ames, Iowa 50011, United States
| | - Mingfeng Cao
- Department of Chemical and Biological
Engineering, ‡NSF Engineering Research Center
for Biorenewable Chemicals (CBiRC), §Department of Chemistry, ∥Interdepartmental Microbiology
Program, Iowa State University, Ames, Iowa 50011, United States
| | - Miguel Suástegui
- Department of Chemical and Biological
Engineering, ‡NSF Engineering Research Center
for Biorenewable Chemicals (CBiRC), §Department of Chemistry, ∥Interdepartmental Microbiology
Program, Iowa State University, Ames, Iowa 50011, United States
| | - James Walker
- Department of Chemical and Biological
Engineering, ‡NSF Engineering Research Center
for Biorenewable Chemicals (CBiRC), §Department of Chemistry, ∥Interdepartmental Microbiology
Program, Iowa State University, Ames, Iowa 50011, United States
| | - Natalia Rodriguez Quiroz
- Department of Chemical and Biological
Engineering, ‡NSF Engineering Research Center
for Biorenewable Chemicals (CBiRC), §Department of Chemistry, ∥Interdepartmental Microbiology
Program, Iowa State University, Ames, Iowa 50011, United States
| | - Yutong Wu
- Department of Chemical and Biological
Engineering, ‡NSF Engineering Research Center
for Biorenewable Chemicals (CBiRC), §Department of Chemistry, ∥Interdepartmental Microbiology
Program, Iowa State University, Ames, Iowa 50011, United States
| | - Dana Tribby
- Department of Chemical and Biological
Engineering, ‡NSF Engineering Research Center
for Biorenewable Chemicals (CBiRC), §Department of Chemistry, ∥Interdepartmental Microbiology
Program, Iowa State University, Ames, Iowa 50011, United States
| | - Adam Okerlund
- Department of Chemical and Biological
Engineering, ‡NSF Engineering Research Center
for Biorenewable Chemicals (CBiRC), §Department of Chemistry, ∥Interdepartmental Microbiology
Program, Iowa State University, Ames, Iowa 50011, United States
| | - Levi Stanley
- Department of Chemical and Biological
Engineering, ‡NSF Engineering Research Center
for Biorenewable Chemicals (CBiRC), §Department of Chemistry, ∥Interdepartmental Microbiology
Program, Iowa State University, Ames, Iowa 50011, United States
| | - Jacqueline V. Shanks
- Department of Chemical and Biological
Engineering, ‡NSF Engineering Research Center
for Biorenewable Chemicals (CBiRC), §Department of Chemistry, ∥Interdepartmental Microbiology
Program, Iowa State University, Ames, Iowa 50011, United States
| | - Zengyi Shao
- Department of Chemical and Biological
Engineering, ‡NSF Engineering Research Center
for Biorenewable Chemicals (CBiRC), §Department of Chemistry, ∥Interdepartmental Microbiology
Program, Iowa State University, Ames, Iowa 50011, United States
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33
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Zhou S, Du G, Kang Z, Li J, Chen J, Li H, Zhou J. The application of powerful promoters to enhance gene expression in industrial microorganisms. World J Microbiol Biotechnol 2017; 33:23. [DOI: 10.1007/s11274-016-2184-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2016] [Accepted: 11/24/2016] [Indexed: 01/01/2023]
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34
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Developing a set of strong intronic promoters for robust metabolic engineering in oleaginous Rhodotorula (Rhodosporidium) yeast species. Microb Cell Fact 2016; 15:200. [PMID: 27887615 PMCID: PMC5124236 DOI: 10.1186/s12934-016-0600-x] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Accepted: 11/19/2016] [Indexed: 01/07/2023] Open
Abstract
Background Red yeast species in the Rhodotorula/Rhodosporidium genus are outstanding producers of triacylglyceride and cell biomass. Metabolic engineering is expected to further enhance the productivity and versatility of these hosts for the production of biobased chemicals and fuels. Promoters with strong activity during oil-accumulation stage are critical tools for metabolic engineering of these oleaginous yeasts. Results The upstream DNA sequences of 6 genes involved in lipid biosynthesis or accumulation in Rhodotorula toruloides were studied by luciferase reporter assay. The promoter of perilipin/lipid droplet protein 1 gene (LDP1) displayed much stronger activity (4–11 folds) than that of glyceraldehyde-3-phosphate dehydrogenase gene (GPD1), one of the strongest promoters known in yeasts. Depending on the stage of cultivation, promoter of acetyl-CoA carboxylase gene (ACC1) and fatty acid synthase β subunit gene (FAS1) exhibited intermediate strength, displaying 50–160 and 20–90% levels of GPD1 promoter, respectively. Interestingly, introns significantly modulated promoter strength at high frequency. The incorporation of intron 1 and 2 of LDP1 (LDP1in promoter) enhanced its promoter activity by 1.6–3.0 folds. Similarly, the strength of ACC1 promoter was enhanced by 1.5–3.2 folds if containing intron 1. The intron 1 sequences of ACL1 and FAS1 also played significant regulatory roles. When driven by the intronic promoters of ACC1 and LDP1 (ACC1in and LDP1in promoter, respectively), the reporter gene expression were up-regulated by nitrogen starvation, independent of de novo oil biosynthesis and accumulation. As a proof of principle, overexpression of the endogenous acyl-CoA-dependent diacylglycerol acyltransferase 1 gene (DGA1) by LDP1in promoter was significantly more efficient than GPD1 promoter in enhancing lipid accumulation. Conclusion Intronic sequences play an important role in regulating gene expression in R. toruloides. Three intronic promoters, LDP1in, ACC1in and FAS1in, are excellent promoters for metabolic engineering in the oleaginous and carotenogenic yeast, R. toruloides. Electronic supplementary material The online version of this article (doi:10.1186/s12934-016-0600-x) contains supplementary material, which is available to authorized users.
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35
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Lechner A, Brunk E, Keasling JD. The Need for Integrated Approaches in Metabolic Engineering. Cold Spring Harb Perspect Biol 2016; 8:cshperspect.a023903. [PMID: 27527588 DOI: 10.1101/cshperspect.a023903] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
This review highlights state-of-the-art procedures for heterologous small-molecule biosynthesis, the associated bottlenecks, and new strategies that have the potential to accelerate future accomplishments in metabolic engineering. We emphasize that a combination of different approaches over multiple time and size scales must be considered for successful pathway engineering in a heterologous host. We have classified these optimization procedures based on the "system" that is being manipulated: transcriptome, translatome, proteome, or reactome. By bridging multiple disciplines, including molecular biology, biochemistry, biophysics, and computational sciences, we can create an integral framework for the discovery and implementation of novel biosynthetic production routes.
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Affiliation(s)
- Anna Lechner
- Joint Bioenergy Institute (JBEI), Emeryville, California 94608.,Department of Chemical & Biomolecular Engineering, Department of Bioengineering, University of California, Berkeley, California 94720
| | - Elizabeth Brunk
- Department of Bioengineering, University of California, San Diego, California 92093
| | - Jay D Keasling
- Joint Bioenergy Institute (JBEI), Emeryville, California 94608.,Department of Chemical & Biomolecular Engineering, Department of Bioengineering, University of California, Berkeley, California 94720.,Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720
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36
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Rajkumar AS, Liu G, Bergenholm D, Arsovska D, Kristensen M, Nielsen J, Jensen MK, Keasling JD. Engineering of synthetic, stress-responsive yeast promoters. Nucleic Acids Res 2016; 44:e136. [PMID: 27325743 PMCID: PMC5041464 DOI: 10.1093/nar/gkw553] [Citation(s) in RCA: 86] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Revised: 05/25/2016] [Accepted: 06/08/2016] [Indexed: 01/01/2023] Open
Abstract
Advances in synthetic biology and our understanding of the rules of promoter architecture have led to the development of diverse synthetic constitutive and inducible promoters in eukaryotes and prokaryotes. However, the design of promoters inducible by specific endogenous or environmental conditions is still rarely undertaken. In this study, we engineered and characterized a set of strong, synthetic promoters for budding yeast Saccharomyces cerevisiae that are inducible under acidic conditions (pH ≤ 3). Using available expression and transcription factor binding data, literature on transcriptional regulation, and known rules of promoter architecture we improved the low-pH performance of the YGP1 promoter by modifying transcription factor binding sites in its upstream activation sequence. The engineering strategy outlined for the YGP1 promoter was subsequently applied to create a response to low pH in the unrelated CCW14 promoter. We applied our best promoter variants to low-pH fermentations, enabling ten-fold increased production of lactic acid compared to titres obtained with the commonly used, native TEF1 promoter. Our findings outline and validate a general strategy to iteratively design and engineer synthetic yeast promoters inducible to environmental conditions or stresses of interest.
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Affiliation(s)
- Arun S Rajkumar
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, 2970 Hørsholm, Denmark
| | - Guodong Liu
- Department of Biology and Biological Engineering, Novo Nordisk Foundation Center for Biosustainability, Chalmers University of Technology, SE-412 96, Gothenburg, Sweden
| | - David Bergenholm
- Department of Biology and Biological Engineering, Novo Nordisk Foundation Center for Biosustainability, Chalmers University of Technology, SE-412 96, Gothenburg, Sweden
| | - Dushica Arsovska
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, 2970 Hørsholm, Denmark
| | - Mette Kristensen
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, 2970 Hørsholm, Denmark
| | - Jens Nielsen
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, 2970 Hørsholm, Denmark Department of Biology and Biological Engineering, Novo Nordisk Foundation Center for Biosustainability, Chalmers University of Technology, SE-412 96, Gothenburg, Sweden
| | - Michael K Jensen
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, 2970 Hørsholm, Denmark
| | - Jay D Keasling
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, 2970 Hørsholm, Denmark Joint BioEnergy Institute, Emeryville, CA 94608, USA Biological Systems & Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA Department of Chemical and Biomolecular Engineering & Department of Bioengineering University of California, Berkeley, CA 94720, USA
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Lian J, Jin R, Zhao H. Construction of plasmids with tunable copy numbers inSaccharomyces cerevisiaeand their applications in pathway optimization and multiplex genome integration. Biotechnol Bioeng 2016; 113:2462-73. [DOI: 10.1002/bit.26004] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2016] [Revised: 04/26/2016] [Accepted: 05/01/2016] [Indexed: 01/13/2023]
Affiliation(s)
- Jiazhang Lian
- Department of Chemical and Biomolecular Engineering; Institute for Genomic Biology, University of Illinois at Urbana-Champaign; Urbana 61801 Illinois
| | - Run Jin
- School of Molecular and Cellular Biology; University of Illinois at Urbana-Champaign; Urbana Illinois
| | - Huimin Zhao
- Department of Chemical and Biomolecular Engineering; Institute for Genomic Biology, University of Illinois at Urbana-Champaign; Urbana 61801 Illinois
- Departments of Chemistry, Biochemistry, and Bioengineering; University of Illinois at Urbana-Champaign; Urbana Illinois
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Leavitt JM, Tong A, Tong J, Pattie J, Alper HS. Coordinated transcription factor and promoter engineering to establish strong expression elements in
Saccharomyces cerevisiae. Biotechnol J 2016; 11:866-76. [DOI: 10.1002/biot.201600029] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Revised: 03/13/2016] [Accepted: 04/26/2016] [Indexed: 12/12/2022]
Affiliation(s)
- John M. Leavitt
- Institute for Cellular and Molecular Biology The University of Texas at Austin Austin Texas USA
| | - Alice Tong
- Institute for Cellular and Molecular Biology The University of Texas at Austin Austin Texas USA
- McKetta Department of Chemical Engineering The University of Texas at Austin Austin Texas USA
| | - Joyce Tong
- Institute for Cellular and Molecular Biology The University of Texas at Austin Austin Texas USA
- McKetta Department of Chemical Engineering The University of Texas at Austin Austin Texas USA
| | - Jonathan Pattie
- Institute for Cellular and Molecular Biology The University of Texas at Austin Austin Texas USA
- McKetta Department of Chemical Engineering The University of Texas at Austin Austin Texas USA
| | - Hal S. Alper
- Institute for Cellular and Molecular Biology The University of Texas at Austin Austin Texas USA
- McKetta Department of Chemical Engineering The University of Texas at Austin Austin Texas USA
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Lynch MD. Into new territory: improved microbial synthesis through engineering of the essential metabolic network. Curr Opin Biotechnol 2016; 38:106-11. [DOI: 10.1016/j.copbio.2016.01.009] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Revised: 01/24/2016] [Accepted: 01/26/2016] [Indexed: 01/21/2023]
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40
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Promoter and Terminator Discovery and Engineering. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2016; 162:21-44. [PMID: 27277391 DOI: 10.1007/10_2016_8] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Abstract
Control of gene expression is crucial to optimize metabolic pathways and synthetic gene networks. Promoters and terminators are stretches of DNA upstream and downstream (respectively) of genes that control both the rate at which the gene is transcribed and the rate at which mRNA is degraded. As a result, both of these elements control net protein expression from a synthetic construct. Thus, it is highly important to discover and engineer promoters and terminators with desired characteristics. This chapter highlights various approaches taken to catalogue these important synthetic elements. Specifically, early strategies have focused largely on semi-rational techniques such as saturation mutagenesis to diversify native promoters and terminators. Next, in an effort to reduce the length of the synthetic biology design cycle, efforts in the field have turned towards the rational design of synthetic promoters and terminators. In this vein, we cover recently developed methods such as hybrid engineering, high throughput characterization, and thermodynamic modeling which allow finer control in the rational design of novel promoters and terminators. Emphasis is placed on the methodologies used and this chapter showcases the utility of these methods across multiple host organisms.
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Abstract
Synthetic biology (SB) is an emerging discipline, which is slowly reorienting the field of drug discovery. For thousands of years, living organisms such as plants were the major source of human medicines. The difficulty in resynthesizing natural products, however, often turned pharmaceutical industries away from this rich source for human medicine. More recently, progress on transformation through genetic manipulation of biosynthetic units in microorganisms has opened the possibility of in-depth exploration of the large chemical space of natural products derivatives. Success of SB in drug synthesis culminated with the bioproduction of artemisinin by microorganisms, a tour de force in protein and metabolic engineering. Today, synthetic cells are not only used as biofactories but also used as cell-based screening platforms for both target-based and phenotypic-based approaches. Engineered genetic circuits in synthetic cells are also used to decipher disease mechanisms or drug mechanism of actions and to study cell-cell communication within bacteria consortia. This review presents latest developments of SB in the field of drug discovery, including some challenging issues such as drug resistance and drug toxicity.
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Affiliation(s)
| | - Pablo Carbonell
- Faculty of Life Sciences, SYNBIOCHEM Centre, Manchester Institute of Biotechnology, University of Manchester, Manchester, UK
- Department of Experimental and Health Sciences (DCEXS), Research Programme on Biomedical Informatics (GRIB), Hospital del Mar Medical Research Institute (IMIM), Universitat Pompeu Fabra (UPF), Barcelona, Spain
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Guan C, Cui W, Cheng J, Zhou L, Guo J, Hu X, Xiao G, Zhou Z. Construction and development of an auto-regulatory gene expression system in Bacillus subtilis. Microb Cell Fact 2015; 14:150. [PMID: 26392346 PMCID: PMC4578258 DOI: 10.1186/s12934-015-0341-2] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2015] [Accepted: 09/12/2015] [Indexed: 01/24/2023] Open
Abstract
BACKGROUND Bacillus subtilis is an all-important Gram-positive bacterium of valuable biotechnological utility that has been widely used to over-produce industrially and pharmaceutically relevant proteins. There are a variety of expression systems in terms of types of transcriptional patterns, among which the auto-inducible and growth-phase-dependent promoters are gaining increasing favor due to their inducer-independent feature, allowing for the potential to industrially scale-up. To expand the applicability of the auto-inducible expression system, a novel auto-regulatory expression system coupled with cell density was constructed and developed in B. subtilis using the quorum-sensing related promoter srfA (PsrfA). RESULTS The promoter of the srf operon was used to construct an expression plasmid with the green fluorescent protein (GFP) downstream of PsrfA. The expression displayed a cell-density-dependent pattern in that GFP had a fairly low expression level at the early exponential stage and was highly expressed at the late exponential as well as the stationary stages. Moreover, the recombinant system had a similar expression pattern in wild-type B. subtilis 168, WB600, and WB800, as well as in B. subtilis 168 derivative strain 1681, with the complete deletion of PsrfA, indicating the excellent compatibility of this system. Noticeably, the expression strength of PsrfA was enhanced by optimizing the -10 and -35 core sequence by substituting both sequences with consensus sequences. Importantly, the expression pattern was successfully developed in an auto-regulatory cell-density coupling system by the simple addition of glucose in which GFP could not be strongly expressed until glucose was depleted, resulting in a greater amount of the GFP product and increased cell density. The expression system was eventually tested by the successful over-production of aminopeptidase to a desired level. CONCLUSION The auto-regulatory cell density coupling system that is mediated by PsrfA is a novel expression system that has an expression pattern that is split between cell-growth and over-expression, leading to an increase in cell density and elevating the overall expression levels of heterologously expressed proteins. The broad applicability of this system and inducer-free expression property in B. subtilis facilitate the industrial scale-up and medical applications for the over-production of a variety of desired proteins.
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Affiliation(s)
- Chengran Guan
- School of Biotechnology, Key Laboratory of Industrial Biotechnology (Ministry of Education), Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu, 214122, China.
| | - Wenjing Cui
- School of Biotechnology, Key Laboratory of Industrial Biotechnology (Ministry of Education), Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu, 214122, China.
| | - Jintao Cheng
- School of Biotechnology, Key Laboratory of Industrial Biotechnology (Ministry of Education), Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu, 214122, China.
| | - Li Zhou
- School of Biotechnology, Key Laboratory of Industrial Biotechnology (Ministry of Education), Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu, 214122, China.
| | - Junling Guo
- School of Biotechnology, Key Laboratory of Industrial Biotechnology (Ministry of Education), Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu, 214122, China.
| | - Xu Hu
- School of Biotechnology, Key Laboratory of Industrial Biotechnology (Ministry of Education), Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu, 214122, China.
| | - Guoping Xiao
- Wuxi Biortus Bioscience Co., Ltd, Wuxi, Jiangsu, 214122, China.
| | - Zhemin Zhou
- School of Biotechnology, Key Laboratory of Industrial Biotechnology (Ministry of Education), Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu, 214122, China.
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White biotechnology: State of the art strategies for the development of biocatalysts for biorefining. Biotechnol Adv 2015; 33:1653-70. [PMID: 26303096 DOI: 10.1016/j.biotechadv.2015.08.004] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2015] [Revised: 07/31/2015] [Accepted: 08/17/2015] [Indexed: 12/31/2022]
Abstract
White biotechnology is a term that is now often used to describe the implementation of biotechnology in the industrial sphere. Biocatalysts (enzymes and microorganisms) are the key tools of white biotechnology, which is considered to be one of the key technological drivers for the growing bioeconomy. Biocatalysts are already present in sectors such as the chemical and agro-food industries, and are used to manufacture products as diverse as antibiotics, paper pulp, bread or advanced polymers. This review proposes an original and global overview of highly complementary fields of biotechnology at both enzyme and microorganism level. A certain number of state of the art approaches that are now being used to improve the industrial fitness of biocatalysts particularly focused on the biorefinery sector are presented. The first part deals with the technologies that underpin the development of industrial biocatalysts, notably the discovery of new enzymes and enzyme improvement using directed evolution techniques. The second part describes the toolbox available by the cell engineer to shape the metabolism of microorganisms. And finally the last part focuses on the 'omic' technologies that are vital for understanding and guide microbial engineering toward more efficient microbial biocatalysts. Altogether, these techniques and strategies will undoubtedly help to achieve the challenging task of developing consolidated bioprocessing (i.e. CBP) readily available for industrial purpose.
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Gritsenko AA, Hulsman M, Reinders MJT, de Ridder D. Unbiased Quantitative Models of Protein Translation Derived from Ribosome Profiling Data. PLoS Comput Biol 2015; 11:e1004336. [PMID: 26275099 PMCID: PMC4537299 DOI: 10.1371/journal.pcbi.1004336] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2014] [Accepted: 05/10/2015] [Indexed: 11/19/2022] Open
Abstract
Translation of RNA to protein is a core process for any living organism. While for some steps of this process the effect on protein production is understood, a holistic understanding of translation still remains elusive. In silico modelling is a promising approach for elucidating the process of protein synthesis. Although a number of computational models of the process have been proposed, their application is limited by the assumptions they make. Ribosome profiling (RP), a relatively new sequencing-based technique capable of recording snapshots of the locations of actively translating ribosomes, is a promising source of information for deriving unbiased data-driven translation models. However, quantitative analysis of RP data is challenging due to high measurement variance and the inability to discriminate between the number of ribosomes measured on a gene and their speed of translation. We propose a solution in the form of a novel multi-scale interpretation of RP data that allows for deriving models with translation dynamics extracted from the snapshots. We demonstrate the usefulness of this approach by simultaneously determining for the first time per-codon translation elongation and per-gene translation initiation rates of Saccharomyces cerevisiae from RP data for two versions of the Totally Asymmetric Exclusion Process (TASEP) model of translation. We do this in an unbiased fashion, by fitting the models using only RP data with a novel optimization scheme based on Monte Carlo simulation to keep the problem tractable. The fitted models match the data significantly better than existing models and their predictions show better agreement with several independent protein abundance datasets than existing models. Results additionally indicate that the tRNA pool adaptation hypothesis is incomplete, with evidence suggesting that tRNA post-transcriptional modifications and codon context may play a role in determining codon elongation rates. Translation, the process of synthesizing proteins from mRNA templates, is an essential biological process in all living organisms. A better understanding of this process will have ramifications in various fields—from gene regulation, disease understanding and medicine to biotechnology and synthetic biology. Nonetheless, a holistic understanding of the processes remains elusive, making computational modelling a promising approach for studying it. However, accurate modelling of translation is challenging due to many assumptions made by such models and due to the sheer number of parameters that need to be specified. Here, we propose to fit models of translation onto ribosome profiling measurements, which record snapshots of the locations of actively translating ribosomes on mRNAs from millions of cells. We develop statistical and computational methods for fitting the Totally Asymmetric Exclusion Process (TASEP) models of translation on these measurements and verify them by deriving highly accurate translation models for the baker’s yeast Saccharomyces cerevisiae, which outperform existing models on independent datasets. We find that fitted elongation rate parameters from the derived models deviate significantly from the widely accepted tRNA pool adaptation hypothesis.
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Affiliation(s)
- Alexey A. Gritsenko
- The Delft Bioinformatics Lab, Department of Intelligent Systems, Delft University of Technology, Delft, The Netherlands
- Platform Green Synthetic Biology, Delft, The Netherlands
- Kluyver Centre for Genomics of Industrial Fermentation, Delft, The Netherlands
| | - Marc Hulsman
- The Delft Bioinformatics Lab, Department of Intelligent Systems, Delft University of Technology, Delft, The Netherlands
| | - Marcel J. T. Reinders
- The Delft Bioinformatics Lab, Department of Intelligent Systems, Delft University of Technology, Delft, The Netherlands
- Kluyver Centre for Genomics of Industrial Fermentation, Delft, The Netherlands
| | - Dick de Ridder
- The Delft Bioinformatics Lab, Department of Intelligent Systems, Delft University of Technology, Delft, The Netherlands
- Platform Green Synthetic Biology, Delft, The Netherlands
- Kluyver Centre for Genomics of Industrial Fermentation, Delft, The Netherlands
- Bioinformatics Group, Wageningen University, Wageningen, The Netherlands
- * E-mail:
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45
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Kushwaha M, Salis HM. A portable expression resource for engineering cross-species genetic circuits and pathways. Nat Commun 2015; 6:7832. [PMID: 26184393 PMCID: PMC4518296 DOI: 10.1038/ncomms8832] [Citation(s) in RCA: 96] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2015] [Accepted: 06/16/2015] [Indexed: 12/24/2022] Open
Abstract
Genetic circuits and metabolic pathways can be reengineered to allow organisms to process signals and manufacture useful chemicals. However, their functions currently rely on organism-specific regulatory parts, fragmenting synthetic biology and metabolic engineering into host-specific domains. To unify efforts, here we have engineered a cross-species expression resource that enables circuits and pathways to reuse the same genetic parts, while functioning similarly across diverse organisms. Our engineered system combines mixed feedback control loops and cross-species translation signals to autonomously self-regulate expression of an orthogonal polymerase without host-specific promoters, achieving nontoxic and tuneable gene expression in diverse Gram-positive and Gram-negative bacteria. Combining 50 characterized system variants with mechanistic modelling, we show how the cross-species expression resource's dynamics, capacity and toxicity are controlled by the control loops' architecture and feedback strengths. We also demonstrate one application of the resource by reusing the same genetic parts to express a biosynthesis pathway in both model and non-model hosts. Organism-specific genetic parts are often used to express circuits and pathways, limiting their portability. Here the authors engineer a cross-species expression resource, without using host-specific parts, to control protein and pathway expression in non-model bacteria.
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Affiliation(s)
- Manish Kushwaha
- Department of Biological Engineering, Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Howard M Salis
- 1] Department of Biological Engineering, Pennsylvania State University, University Park, Pennsylvania 16802, USA [2] Department of Chemical Engineering, Pennsylvania State University, University Park, Pennsylvania 16802, USA
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46
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The development and characterization of synthetic minimal yeast promoters. Nat Commun 2015; 6:7810. [PMID: 26183606 PMCID: PMC4518256 DOI: 10.1038/ncomms8810] [Citation(s) in RCA: 162] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2015] [Accepted: 06/15/2015] [Indexed: 01/11/2023] Open
Abstract
Synthetic promoters, especially minimally sized, are critical for advancing fungal synthetic biology. Fungal promoters often span hundreds of base pairs, nearly ten times the amount of bacterial counterparts. This size limits large-scale synthetic biology efforts in yeasts. Here we address this shortcoming by establishing a methodical workflow necessary to identify robust minimal core elements that can be linked with minimal upstream activating sequences to develop short, yet strong yeast promoters. Through a series of library-based synthesis, analysis and robustness tests, we create a set of non-homologous, purely synthetic, minimal promoters for yeast. These promoters are comprised of short core elements that are generic and interoperable and 10 bp UAS elements that impart strong, constitutive function. Through this methodology, we are able to generate the shortest fungal promoters to date, which can achieve high levels of both inducible and constitutive expression with up to an 80% reduction in size. Endogenous fungal gene promoters can be hundreds of base pairs long, limiting their use in synthetic biology and biotechnology. Here Redden and Alper screen a library of synthetic promoter elements to generate compact DNA sequences of ∼100 base pairs able to drive high levels of gene expression.
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47
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Mimee M, Tucker AC, Voigt CA, Lu TK. Programming a Human Commensal Bacterium, Bacteroides thetaiotaomicron, to Sense and Respond to Stimuli in the Murine Gut Microbiota. Cell Syst 2015; 1:62-71. [PMID: 26918244 DOI: 10.1016/j.cels.2015.06.001] [Citation(s) in RCA: 204] [Impact Index Per Article: 22.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Engineering commensal organisms for challenging applications, such as modulating the gut ecosystem, is hampered by the lack of genetic parts. Here, we describe promoters, ribosome-binding sites, and inducible systems for use in the commensal bacterium Bacteroides thetaiotaomicron, a prevalent and stable resident of the human gut. We achieve up to 10,000-fold range in constitutive gene expression and 100-fold regulation of gene expression with inducible promoters and use these parts to record DNA-encoded memory in the genome. We use CRISPR interference (CRISPRi) for regulated knockdown of recombinant and endogenous gene expression to alter the metabolic capacity of B. thetaiotaomicron and its resistance to antimicrobial peptides. Finally, we show that inducible CRISPRi and recombinase systems can function in B. thetaiotaomicron colonizing the mouse gut. These results provide a blueprint for engineering new chassis and a resource to engineer Bacteroides for surveillance of or therapeutic delivery to the gut microbiome.
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Affiliation(s)
- Mark Mimee
- Department of Biological Engineering, Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; MIT Microbiology Program, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Alex C Tucker
- Department of Biological Engineering, Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Christopher A Voigt
- Department of Biological Engineering, Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Timothy K Lu
- Department of Biological Engineering, Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; MIT Microbiology Program, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
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