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Gao S, Liao Y, He H, Yang H, Yang X, Xu S, Wang X, Chen K, Ouyang P. Advance of tolerance engineering on microbes for industrial production. Synth Syst Biotechnol 2023; 8:697-707. [PMID: 38025766 PMCID: PMC10656194 DOI: 10.1016/j.synbio.2023.10.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2023] [Revised: 10/19/2023] [Accepted: 10/23/2023] [Indexed: 12/01/2023] Open
Abstract
Industrial microbes have become the core of biological manufacturing, which utilized as the cell factory for production of plenty of chemicals, fuels and medicine. However, the challenge that the extreme stress conditions exist in production is unavoidable for cell factory. Consequently, to enhance robustness of the chassis cell lays the foundation for development of bio-manufacturing. Currently, the researches on cell tolerance covered various aspects, involving reshaping regulatory network, cell membrane modification and other stress response. In fact, the strategies employed to improve cell robustness could be summarized into two directions, irrational engineering and rational engineering. In this review, the metabolic engineering technologies on enhancement of microbe tolerance to industrial conditions are summarized. Meanwhile, the novel thoughts emerged with the development of biological instruments and synthetic biology are discussed.
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Affiliation(s)
- Siyuan Gao
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, 211816, Jiangsu, China
| | - Yang Liao
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, 211816, Jiangsu, China
| | - Hao He
- Petrochemical Research Institute of PetroChina Co. Ltd., Beijing, 102206, China
| | - Huiling Yang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, 211816, Jiangsu, China
| | - Xuewei Yang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, 211816, Jiangsu, China
| | - Sheng Xu
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, 211816, Jiangsu, China
| | - Xin Wang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, 211816, Jiangsu, China
| | - Kequan Chen
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, 211816, Jiangsu, China
| | - Pingkai Ouyang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, 211816, Jiangsu, China
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Biosensor-assisted evolution for high-level production of 4-hydroxyphenylacetic acid in Escherichia coli. Metab Eng 2021; 70:1-11. [PMID: 34965469 DOI: 10.1016/j.ymben.2021.12.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Revised: 12/17/2021] [Accepted: 12/21/2021] [Indexed: 11/21/2022]
Abstract
4-Hydroxyphenylacetic acid (4HPAA) is an important building block for synthesizing drugs, agrochemicals, and biochemicals, and requires sustainable production to meet increasing demand. Here, we use a 4HPAA biosensor to overcome the difficulty of conventional library screening in identification of preferred mutants. Strains with higher 4HPAA production and tolerance are successfully obtained by atmospheric and room temperature plasma (ARTP) mutagenesis coupled with adaptive laboratory evolution using this biosensor. Genome shuffling integrates preferred properties in the strain GS-2-4, which produces 25.42 g/L 4HPAA. Chromosomal mutations of the strain GS-2-4 are identified by whole genome sequencing. Through comprehensive analysis and experimental validation, important genes, pathways and regulations are revealed. The best gene combination in inverse engineering, acrD-aroG, increases 4HPAA production of strain GS-2-4 by 37% further. These results emphasize precursor supply and stress resistance are keys to efficient 4HPAA biosynthesis. Our work shows the power of biosensor-assisted screening of mutants from libraries. The methods developed here can be easily adapted to construct cell factories for the production of other aromatic chemicals. Our work also provides many valuable target genes to build cell factories for efficient 4HPAA production in the future.
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Niu FX, He X, Huang YB, Liu JZ. Biosensor-Guided Atmospheric and Room-Temperature Plasma Mutagenesis and Shuffling for High-Level Production of Shikimic Acid from Sucrose in Escherichia coli. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2020; 68:11765-11773. [PMID: 33030899 DOI: 10.1021/acs.jafc.0c05253] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Here, we first developed a combined strain improvement strategy of biosensor-guided atmospheric and room-temperature plasma mutagenesis and genome shuffling. Application of this strategy resulted in a 2.7-fold increase in the production of shikimic acid (SA) and a 2.0-fold increase in growth relative to those of the starting strain. Whole-cell resequencing of the shuffled strain and confirmation using CRISPRa/CRISPRi revealed that some membrane protein-related mutant genes are identified as being closely related to the higher SA titer. The engineered shuffling strain produced 18.58 ± 0.56 g/L SA from glucose with a yield of 68% (mol/mol) by fed-batch whole-cell biocatalysis, achieving 79% of the theoretical maximum. Sucrose-utilizing Escherichia coli was engineered for SA production by introducing Mannheimia succiniciproducens β-fructofuranosidase gene. The resulting sucrose-utilizing E. coli strain produced 24.64 ± 0.32 g/L SA from sucrose with a yield of 1.42 mol/mol by fed-batch whole-cell biocatalysis, achieving 83% of the theoretical maximum.
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Affiliation(s)
- Fu-Xing Niu
- Institute of Synthetic Biology, MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China
| | - Xin He
- Institute of Synthetic Biology, MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China
| | - Yuan-Bin Huang
- Institute of Synthetic Biology, MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China
| | - Jian-Zhong Liu
- Institute of Synthetic Biology, MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China
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Brown DM, Glass JI. Technology used to build and transfer mammalian chromosomes. Exp Cell Res 2020; 388:111851. [PMID: 31952951 DOI: 10.1016/j.yexcr.2020.111851] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Revised: 01/09/2020] [Accepted: 01/14/2020] [Indexed: 01/05/2023]
Abstract
In the near twenty-year existence of the human and mammalian artificial chromosome field, the technologies for artificial chromosome construction and installation into desired cell types or organisms have evolved with the rest of modern molecular and synthetic biology. Medical, industrial, pharmaceutical, agricultural, and basic research scientists seek the as yet unrealized promise of human and mammalian artificial chromosomes. Existing technologies for both top-down and bottom-up approaches to construct these artificial chromosomes for use in higher eukaryotes are very different but aspire to achieve similar results. New capacity for production of chromosome sized synthetic DNA will likely shift the field towards more bottom-up approaches, but not completely. Similarly, new approaches to install human and mammalian artificial chromosomes in target cells will compete with the microcell mediated cell transfer methods that currently dominate the field.
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Tabata KV, Sogo T, Moriizumi Y, Noji H. Regeneration of Escherichia coli Giant Protoplasts to Their Original Form. Life (Basel) 2019; 9:life9010024. [PMID: 30832265 PMCID: PMC6463199 DOI: 10.3390/life9010024] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2019] [Revised: 02/23/2019] [Accepted: 02/24/2019] [Indexed: 11/20/2022] Open
Abstract
The spheroplasts and protoplasts of cell wall-deficient (CWD) bacteria are able to revert to their original cellular morphologies through the regeneration of their cell walls. However, whether this is true for giant protoplasts (GPs), which can be as large as 10 μm in diameter, is unknown. GPs can be prepared from various bacteria, including Escherichia coli and Bacillus subtilis, and also from fungi, through culture in the presence of inhibitors for cell wall synthesis or mitosis. In this report, we prepared GPs from E. coli and showed that they can return to rod-shaped bacterium, and that they are capable of colony formation. Microscopic investigation revealed that the regeneration process took place through a variety of morphological pathways. We also report the relationship between GP division and GP volume. Finally, we show that FtsZ is crucial for GP division. These results indicate that E. coli is a highly robust organism that can regenerate its original form from an irregular state, such as GP.
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Affiliation(s)
- Kazuhito V Tabata
- Department of Applied Chemistry, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Japan.
| | - Takao Sogo
- Department of Applied Chemistry, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Japan.
| | - Yoshiki Moriizumi
- Department of Applied Chemistry, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Japan.
| | - Hiroyuki Noji
- Department of Applied Chemistry, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Japan.
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Zhang P, Lee Y, Wei X, Wu J, Liu Q, Wan S. Enhanced production of tanshinone IIA in endophytic fungi Emericella foeniculicola by genome shuffling. PHARMACEUTICAL BIOLOGY 2018; 56:357-362. [PMID: 30266071 PMCID: PMC6171462 DOI: 10.1080/13880209.2018.1481108] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Revised: 03/14/2018] [Accepted: 05/16/2018] [Indexed: 06/08/2023]
Abstract
CONTEXT Tanshinone IIA, commercially produced from Salvia miltiorrhiza Bunge (C.Y.Wu) (Labiatae), has various biological benefits. Currently, this compound is mainly extracted from plants. However, because of the long growth cycle and the unstable quality of plants, the market demands can barely be satisfied. OBJECTIVE The genomic shuffling technology is applied to screen the high-yield tanshinone IIA strain, which could be used to replace the plant S. miltiorrhiza for the production of tanshinone IIA. The change in the production of tanshinone IIA is clarified by comparing it with the original strain. MATERIALS AND METHODS Tanshinone IIA was extracted from Strains cells, which was prepared through 0.5 mL protoplast samples by using hypertonic solution I from two different strains. Then, it was analyzed by high-performance liquid chromatography at 30 °C and UV 270 nm. Total DNA from the strains was extracted for RAPD amplification and electrophoresis to isolate the product. RESULTS In this study, a high-yield tanshinone IIA strain F-3.4 was screened and the yield of tanshinone IIA was increased by 387.56 ± 0.02 mg/g, 11.07 times higher than that of the original strain TR21. DISCUSSION This study shows that the genetic basis of high-yield strains is achieved through genome shuffling, which proves that genome shuffling can shorten the breeding cycle and improve the mutagenesis efficiency in obtaining the strains with good traits and it is a useful method for the molecular breeding of industrial strains.
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Affiliation(s)
- Pengyu Zhang
- College of Life Sciences, Shaanxi Normal University, Chang’an Campus, Xi’an, Shaanxi, China
| | - Yiting Lee
- College of Life Sciences, Shaanxi Normal University, Chang’an Campus, Xi’an, Shaanxi, China
| | - Xiying Wei
- College of Life Sciences, Shaanxi Normal University, Chang’an Campus, Xi’an, Shaanxi, China
| | - Jinlan Wu
- College of Life Sciences, Shaanxi Normal University, Chang’an Campus, Xi’an, Shaanxi, China
| | - Qingmei Liu
- College of Life Sciences, Shaanxi Normal University, Chang’an Campus, Xi’an, Shaanxi, China
| | - Shanning Wan
- College of Life Sciences, Shaanxi Normal University, Chang’an Campus, Xi’an, Shaanxi, China
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Improved antimicrobial activity of Pediococcus acidilactici against Salmonella Gallinarum by UV mutagenesis and genome shuffling. Appl Microbiol Biotechnol 2017; 101:5353-5363. [DOI: 10.1007/s00253-017-8293-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Revised: 04/02/2017] [Accepted: 04/06/2017] [Indexed: 11/25/2022]
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Building cellular pathways and programs enabled by the genetic diversity of allo-genomes and meta-genomes. Curr Opin Biotechnol 2015; 36:16-31. [DOI: 10.1016/j.copbio.2015.08.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2015] [Revised: 08/06/2015] [Accepted: 08/09/2015] [Indexed: 12/21/2022]
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9
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Zhang G, Lin Y, Qi X, Wang L, He P, Wang Q, Ma Y. Genome shuffling of the nonconventional yeast Pichia anomala for improved sugar alcohol production. Microb Cell Fact 2015; 14:112. [PMID: 26246027 PMCID: PMC4527335 DOI: 10.1186/s12934-015-0303-8] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2015] [Accepted: 07/22/2015] [Indexed: 08/30/2023] Open
Abstract
Background Sugar alcohols have been widely applied in the fields of food and medicine owing to their unique properties. Compared to chemical production, microbial production of sugar alcohols has become attractive because of its environmentally friendly and sustainable characteristics. Our previous study identified the nonconventional yeast Pichia anomala TIB-x229 as a potential producer of sugar alcohols from glucose. To further improve strain performance, we combined genome shuffling with optimized high throughput screening methods for the directed improvement of nonconventional yeast and complex phenotypes. Results To accelerate strain improvement, a practical genome shuffling procedure was developed and successfully applied in the nonconventional yeast P. anomala to increase sugar alcohol production. Through two rounds of genome shuffling, an improved P. anomala isolate GS2-3 could produce 47.1 g/L total sugar alcohols from 100 g/L glucose, which was 32.3% higher than the original strain. In this process, a simple and accurate colorimetric assay was optimized and used for high throughput screening of sugar alcohol-producing strains. Moreover, a fluorescence-activated cell sorting method was developed to efficiently screen protoplast fusions for genome shuffling of nonconventional yeast. Conclusion An efficient genome shuffling procedure was developed and applied to enhance the sugar alcohol production of the nonconventional yeast P. anomala. Our results provide a general platform for strain improvement of polyol-producing microorganisms or nonconventional microorganisms in the future. Electronic supplementary material The online version of this article (doi:10.1186/s12934-015-0303-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Guoqiang Zhang
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 XiQiDao, Tianjin Airport Economic Area, Tianjin, 300308, China. .,University of Chinese Academy of Sciences, Beijing, 100049, China.
| | - Yuping Lin
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 XiQiDao, Tianjin Airport Economic Area, Tianjin, 300308, China.
| | - Xianni Qi
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 XiQiDao, Tianjin Airport Economic Area, Tianjin, 300308, China.
| | - Lixian Wang
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 XiQiDao, Tianjin Airport Economic Area, Tianjin, 300308, China.
| | - Peng He
- Key Laboratory of Microbial Physiological and Metabolic Engineering, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China.
| | - Qinhong Wang
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 XiQiDao, Tianjin Airport Economic Area, Tianjin, 300308, China.
| | - Yanhe Ma
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 XiQiDao, Tianjin Airport Economic Area, Tianjin, 300308, China.
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10
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Genome shuffling of Lactobacillus brevis for enhanced production of thymidine phosphorylase. BIOTECHNOL BIOPROC E 2015. [DOI: 10.1007/s12257-014-0617-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Chi Z, Rong YJ, Li Y, Tang MJ, Chi ZM. Biosurfactins production by Bacillus amyloliquefaciens R3 and their antibacterial activity against multi-drug resistant pathogenic E. coli. Bioprocess Biosyst Eng 2015; 38:853-61. [PMID: 25407729 DOI: 10.1007/s00449-014-1328-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2014] [Accepted: 11/09/2014] [Indexed: 10/24/2022]
Abstract
In this work, the anti-Escherichia coli activity of the bioactive substances produced by Bacillus amyloliquefaciens R3 was examined. A new and cheap medium for production of the anti-E. coli substances which contained 20.0 g L(-1) soybean powder, 20.0 g L(-1) wheat flour, pH 6.0 was developed. A crude surfactant concentration of 0.48 mg mL(-1) was obtained after 27 h of 10-L fermentation, and the diameter of the clear zone on the plate seeded with the pathogenic E. coli 2# was 23.3 mm. A preliminary characterization suggested that the anti-E. coli substances produced by B. amyloliquefaciens R3 were the biosurfactins (F1, F2, F3, F4, and F5) with amino acids (GLLVDLL) and hydroxy fatty acids (of 12-15 carbons in length). It was found that all the strains of the pathogenic E. coli showed resistance to several different antibiotics, suggesting that they were the multi-drug resistance and all the strains of the pathogenic E. coli were sensitive to the biosurfactins, indicating that the biosurfactins produced by B. amyloliquefaciens R3 had a broad spectrum of antibacterial activity against the pathogenic E. coli with multi-drug resistant profiles. After the treatment with the purified biosurfactin (F1), the cell membrane of both the whole cells and protoplasts of the E. coli 2# was damaged and the whole cells of the bacterium were broken.
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Affiliation(s)
- Zhe Chi
- Unesco Chinese Center of Marine Biotechnology, Ocean University of China, Yushan Road, No. 5, Qingdao, 266003, China
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Liu W, Jiang R. Combinatorial and high-throughput screening approaches for strain engineering. Appl Microbiol Biotechnol 2015; 99:2093-104. [DOI: 10.1007/s00253-015-6400-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2014] [Revised: 01/09/2015] [Accepted: 01/10/2015] [Indexed: 12/31/2022]
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Ding S, Zhang Y, Zhang J, Zeng W, Yang Y, Guan J, Pan L, Li W. Enhanced deacidification activity in Schizosaccharomyces pombe by genome shuffling. Yeast 2014; 32:317-25. [PMID: 25377082 DOI: 10.1002/yea.3053] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Revised: 10/24/2014] [Accepted: 10/29/2014] [Indexed: 11/07/2022] Open
Abstract
A problem frequently occurring in making some kinds of wines, particularly Vitis quinquangularis Rehd wine, is the presence of malic acid at high concentrations, which is detrimental to the quality of wines. Thus, there is a need of the ways for effectively reducing the malic acid levels in wine. This study aimed to generate shuffled fusants of Schizosaccharomyces pombe with enhanced deacidification activity for reducing the excessive malic acid content in wine. Sz. pombe CGMCC 2.1628 was used as the original strain. The starting mutant population was generated by UV treatment. The mutants with higher deacidification activity were selected and subjected to recursive protoplast fusion. The resulting fusants were screened by using the indicator of malic acid concentration of fermentation supernatants on 96-well microtitre plates, measured with bromocresol green. After three rounds of genome shuffling, the best-performing fusant, named GS3-1, was obtained. Its deacidification activity (consumed 4.78 g/l malic acid within 10 days) was increased by 225.2% as compared to that of original strain. In the Vitis quinquangularis Rehd wine fermentation test, GS3-1 consumed 4.0 g/l malic acid during the whole cycle of fermentation, providing up to 185.7% improvement in malic acid consumption compared with that of the original strain. This study shows that GS3-1 has great potential for improving the quality of Vitis quinquangularis Rehd wine.
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Affiliation(s)
- Su Ding
- Xingjian College of Science and Liberal Arts, Guangxi University, People's Republic of China; Key Laboratory of Ministry of Education for Microbial and Plant Genetic Engineering, Guangxi University, People's Republic of China
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Transferring whole genomes from bacteria to yeast spheroplasts using entire bacterial cells to reduce DNA shearing. Nat Protoc 2014; 9:743-50. [PMID: 24603933 DOI: 10.1038/nprot.2014.045] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Direct cell-to-cell transfer of genomes from bacteria to yeast facilitates genome engineering for bacteria that are not amenable to genetic manipulation by allowing instead for the utilization of the powerful yeast genetic tools. Here we describe a protocol for transferring whole genomes from bacterial cells to yeast spheroplasts without any DNA purification process. The method is dependent on the treatment of the bacterial and yeast cellular mixture with PEG, which induces cell fusion, engulfment, aggregation or lysis. Over 80% of the bacterial genomes transferred in this way are complete, on the basis of structural and functional tests. Excluding the time required for preparing starting cultures and for incubating cells to form final colonies, the protocol can be completed in 3 h.
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Evolutionary engineering by genome shuffling. Appl Microbiol Biotechnol 2014; 98:3877-87. [PMID: 24595425 DOI: 10.1007/s00253-014-5616-8] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2013] [Revised: 02/11/2014] [Accepted: 02/12/2014] [Indexed: 01/28/2023]
Abstract
An upsurge in the bioeconomy drives the need for engineering microorganisms with increasingly complex phenotypes. Gains in productivity of industrial microbes depend on the development of improved strains. Classical strain improvement programmes for the generation, screening and isolation of such mutant strains have existed for several decades. An alternative to traditional strain improvement methods, genome shuffling, allows the directed evolution of whole organisms via recursive recombination at the genome level. This review deals chiefly with the technical aspects of genome shuffling. It first presents the diversity of organisms and phenotypes typically evolved using this technology and then reviews available sources of genetic diversity and recombination methodologies. Analysis of the literature reveals that genome shuffling has so far been restricted to microorganisms, both prokaryotes and eukaryotes, with an overepresentation of antibiotics- and biofuel-producing microbes. Mutagenesis is the main source of genetic diversity, with few studies adopting alternative strategies. Recombination is usually done by protoplast fusion or sexual recombination, again with few exceptions. For both diversity and recombination, prospective methods that have not yet been used are also presented. Finally, the potential of genome shuffling for gaining insight into the genetic basis of complex phenotypes is also discussed.
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Zhao E, Hong Y, Chen S, Leung CWT, Chan CYK, Kwok RTK, Lam JWY, Tang BZ. Highly fluorescent and photostable probe for long-term bacterial viability assay based on aggregation-induced emission. Adv Healthc Mater 2014; 3:88-96. [PMID: 23814037 DOI: 10.1002/adhm.201200475] [Citation(s) in RCA: 93] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2012] [Revised: 03/27/2013] [Indexed: 12/17/2022]
Abstract
Long-term tracking of bacterial viability is of great importance for monitoring the viability change of bacteria under storage, evaluating disinfection efficiency, as well as for studying the pharmacokinetic and pharmacodynamic properties of antibacterials. Most of the conventional viability dyes, however, suffer from high toxicity and/or poor photostability, making them unsuitable for long-term studies. In this work, an aggregation-induced emission molecule, TPE-2BA, which can differentiate dead and living bacteria and serve as a highly fluorescent and photostable probe for long-term viability assay. TPE-2BA is a cell-impermeable DNA stain that binds to the groove of double-stranded DNA. Bacteria with compromised membrane open the access for TPE-2BA to reach DNA, endowing it with strong emission. The feasibility of using TPE-2BA for screening effective bactericides is also demonstrated. Plate count experiment reveals that TPE-2BA poses negligible toxicity to bacteria, indicating that it is an excellent probe for long-term bacterial viability assay.
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Affiliation(s)
- Engui Zhao
- Division of Biomedical Engineering, The Hong Kong University of Science & Technology (HKUST), Clear Water Bay, Kowloon, Hong Kong, China
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Xu HM, Rong YJ, Zhao MX, Song B, Chi ZM. Antibacterial activity of the lipopetides produced by Bacillus amyloliquefaciens M1 against multidrug-resistant Vibrio spp. isolated from diseased marine animals. Appl Microbiol Biotechnol 2013; 98:127-36. [PMID: 24132666 DOI: 10.1007/s00253-013-5291-1] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2013] [Revised: 09/03/2013] [Accepted: 09/20/2013] [Indexed: 10/26/2022]
Abstract
In this work, the antibacterial activity of the lipopeptides produced by Bacillus amyloliquefaciens M1 was examined against multidrug-resistant Vibrio spp. and Shewanella aquimarina isolated from diseased marine animals. A new and cheap medium which contained 1.0 % soybean powder, 1.5 % wheat flour, pH 7.0 was developed. A crude surfactant concentration of 0.28 mg/ml was obtained after 18 h of 10-l fermentation and diameter of the clear zone on the plate seeded with Vibrio anguillarum was 34 mm. A preliminary characterization suggested that the lipopeptide N3 produced by B. amyloliquefaciens M1 was the main product and contained the surfactin isoforms with amino acids (GLLVDLL) and hydroxy fatty acids (of 12-15 carbons in length). The evaluation of the antibacterial activity of the lipopeptide N3 was carried out against S. aquimarina and nine species of Vibrio spp.. It was found that all the Vibrio spp. and S. aquimarina showed resistance to several different antibiotics, suggesting that they were the multidrug resistance. It was also indicated that all the Vibrio spp. strains and S. aquimarina were sensitive to the surfactin N3, in particular V. anguillarum. The results demonstrated that the lipopeptides produced by B. amyloliquefaciens M1 had a broad spectrum of action, including antibacterial activity against the pathogenic Vibrio spp. with multidrug-resistant profiles. After the treatment with the lipopeptide N3, the cell membrane of V. anguillarum was damaged, and the whole cells of the bacterium were disrupted.
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Affiliation(s)
- Hong-Mei Xu
- UNESCO Chinese Center of Marine Biotechnology, Ocean University of China, Yushan Road, No. 5, Qingdao, 266003, China
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18
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Genome Shuffling of Aspergillus niger for Improving Transglycosylation Activity. Appl Biochem Biotechnol 2013; 172:50-61. [DOI: 10.1007/s12010-013-0421-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2013] [Accepted: 07/31/2013] [Indexed: 10/26/2022]
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Wang H, Sun Y, Chen C, Sun Z, Zhou Y, Shen F, Zhang H, Dai Y. Genome shuffling of Lactobacillus plantarum for improving antifungal activity. Food Control 2013. [DOI: 10.1016/j.foodcont.2012.12.020] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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20
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Skretas G, Kolisis FN. Combinatorial approaches for inverse metabolic engineering applications. Comput Struct Biotechnol J 2013; 3:e201210021. [PMID: 24688681 PMCID: PMC3962077 DOI: 10.5936/csbj.201210021] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2012] [Revised: 02/11/2013] [Accepted: 02/17/2013] [Indexed: 11/22/2022] Open
Abstract
Traditional metabolic engineering analyzes biosynthetic and physiological pathways, identifies bottlenecks, and makes targeted genetic modifications with the ultimate goal of increasing the production of high-value products in living cells. Such efforts have led to the development of a variety of organisms with industrially relevant properties. However, there are a number of cellular phenotypes important for research and the industry for which the rational selection of cellular targets for modification is not easy or possible. In these cases, strain engineering can be alternatively carried out using “inverse metabolic engineering”, an approach that first generates genetic diversity by subjecting a population of cells to a particular mutagenic process, and then utilizes genetic screens or selections to identify the clones exhibiting the desired phenotype. Given the availability of an appropriate screen for a particular property, the success of inverse metabolic engineering efforts usually depends on the level and quality of genetic diversity which can be generated. Here, we review classic and recently developed combinatorial approaches for creating such genetic diversity and discuss the use of these methodologies in inverse metabolic engineering applications.
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Affiliation(s)
- Georgios Skretas
- Institute of Biology, Medicinal Chemistry and Biotechnology, National Hellenic Research Foundation, Athens, Greece
| | - Fragiskos N Kolisis
- Biotechnology Laboratory, School of Chemical Engineering, National Technical University of Athens - Zografou Campus, Athens, Greece
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21
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The simultaneous production of single-cell protein and a recombinant antibacterial peptide by expression of an antibacterial peptide gene in Yarrowia lipolytica. Process Biochem 2013. [DOI: 10.1016/j.procbio.2013.01.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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22
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The target of daptomycin is absent from Escherichia coli and other gram-negative pathogens. Antimicrob Agents Chemother 2012; 57:637-9. [PMID: 23114759 DOI: 10.1128/aac.02005-12] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Antistaphylococcal agents commonly lack activity against Gram-negative bacteria like Escherichia coli owing to the permeability barrier presented by the outer membrane and/or the action of efflux transporters. When these intrinsic resistance mechanisms are artificially compromised, such agents almost invariably demonstrate antibacterial activity against Gram negatives. Here we show that this is not the case for the antibiotic daptomycin, whose target appears to be absent from E. coli and other Gram-negative pathogens.
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23
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Harnessing recombination to speed adaptive evolution in Escherichia coli. Metab Eng 2012; 14:487-95. [PMID: 22842472 DOI: 10.1016/j.ymben.2012.07.004] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2012] [Revised: 07/14/2012] [Accepted: 07/19/2012] [Indexed: 01/12/2023]
Abstract
Evolutionary engineering typically involves asexual propagation of a strain to improve a desired phenotype. However, asexual populations suffer from extensive clonal interference, a phenomenon where distinct lineages of beneficial clones compete and are often lost from the population given sufficient time. Improved adaptive mutants can likely be generated by genetic exchange between lineages, thereby reducing clonal interference. We present a system that allows continuous in situ recombination by using an Esherichia coli F-based conjugation system lacking surface exclusion. Evolution experiments revealed that Hfr-mediated recombination significantly speeds adaptation in certain circumstances. These results show that our system is stable, effective, and suitable for use in evolutionary engineering applications.
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24
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Luo JM, Li JS, Liu D, Liu F, Wang YT, Song XR, Wang M. Genome shuffling of Streptomyces gilvosporeus for improving natamycin production. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2012; 60:6026-6036. [PMID: 22607399 DOI: 10.1021/jf300663w] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Improvement of natamycin production by Streptomyces gilvosporeus ATCC 13326 was performed by recursive protoplast fusion in a genome-shuffling format. After four rounds of genome shuffling, the best producer, GS 4-21, with genetic stability was obtained and its production of natamycin reached 4.69 ± 0.05 g/L in shaking flask after 96 h cultivation, which was increased by 97.1% and 379% in comparison with the highest parental strain pop-72A(r)07 and the initial strain ATCC 13326, respectively. Compared with the initial strain ATCC 13326, the recombinant GS 4-21 presented higher polymorphism. Fifty-four proteins showed differential expression levels between the recombinant GS 4-21 and initial strain ATCC 13326. Of these proteins, 34 proteins were upregulated and 20 proteins were downregulated. Of the upregulated proteins, one protein, glucokinase regulatory protein, was involved in natamycin biosynthesis. This comprehensive analysis would provide useful information for understanding the natamycin metabolic pathway in S. gilvosporeus.
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Affiliation(s)
- Jian-Mei Luo
- Key Laboratory of Industrial Fermentation Microbiology (Tianjin University of Science and Technology), Ministry of Education, Tianjin Key Lab of Industrial Microbiology, College of Biotechnology, Tianjin University of Science and Technology, Tianjin 300457, People's Republic of China
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25
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Reyes LH, Almario MP, Winkler J, Orozco MM, Kao KC. Visualizing evolution in real time to determine the molecular mechanisms of n-butanol tolerance in Escherichia coli. Metab Eng 2012; 14:579-90. [PMID: 22652227 DOI: 10.1016/j.ymben.2012.05.002] [Citation(s) in RCA: 88] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2011] [Revised: 04/30/2012] [Accepted: 05/17/2012] [Indexed: 11/25/2022]
Abstract
Toxicity of products or feedstock components poses a challenge in the biocatalyst-based production of fuels and chemicals. The genetic determinants that are involved in increased resistance to an inhibitor form the adaptive landscape for the phenotype; so in order to engineer more robust biocatalysts, a better understanding of the adaptive landscape is required. Here, we used an adaptive laboratory evolution method called visualizing evolution in real time (VERT) to help map out part of the adaptive landscape of Escherichia coli tolerance to the biofuel n-butanol. VERT enables identification of adaptive events (population expansions triggered by adaptive mutants) via visualization of the relative proportions of different fluorescently-labeled cells. Knowledge of the occurrence of adaptive events allows for a more systematic isolation of adaptive mutants while simultaneously reducing the number of missed adaptive mutants (and the underlying adaptive mechanisms) that result from clonal interference during the course of in vitro evolution. Based on the evolutionary dynamics observed, clonal interference was found to play a significant role in shaping the population structure of E. coli during exposure to n-butanol, and VERT helped to facilitate the isolation of adaptive mutants from the population. We further combined adaptive laboratory evolution with genome shuffling to significantly enhance the desired n-butanol tolerance phenotype. Subsequent transcriptome analysis of the isolated adaptive mutants revealed different mechanisms of n-butanol resistance in different lineages. In one fluorescently-marked subpopulation, members of the Fur regulon were upregulated; which was not observed in the other subpopulation. In addition, genome sequencing of several adaptive mutants revealed the genetic basis for some of the observed transcriptome profiles. We further elucidated the potential role of the iron-related gene in n-butanol tolerance via overexpression and deletion studies and hypothesized that the upregulation of the iron-related genes indirectly led to modifications in the outer membrane, which contributed to enhanced n-butanol tolerance.
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Affiliation(s)
- Luis H Reyes
- Department of Chemical Engineering, Texas A&M University, College Station, TX, USA
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26
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Kumar M, Pratap Singh M, Kumar Tuli D. Genome Shuffling of <i>Pseudomonas</i> Sp. Ioca11 for Improving Degradation of Polycyclic Aromatic Hydrocarbons. ACTA ACUST UNITED AC 2012. [DOI: 10.4236/aim.2012.21004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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27
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Genome shuffling improves production of the low-temperature alkalophilic lipase by Acinetobacter johnsonii. Biotechnol Lett 2011; 34:145-51. [DOI: 10.1007/s10529-011-0749-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2011] [Accepted: 09/21/2011] [Indexed: 10/17/2022]
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28
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Makino T, Skretas G, Georgiou G. Strain engineering for improved expression of recombinant proteins in bacteria. Microb Cell Fact 2011; 10:32. [PMID: 21569582 PMCID: PMC3120638 DOI: 10.1186/1475-2859-10-32] [Citation(s) in RCA: 138] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2011] [Accepted: 05/14/2011] [Indexed: 01/17/2023] Open
Abstract
Protein expression in Escherichia coli represents the most facile approach for the preparation of non-glycosylated proteins for analytical and preparative purposes. So far, the optimization of recombinant expression has largely remained a matter of trial and error and has relied upon varying parameters, such as expression vector, media composition, growth temperature and chaperone co-expression. Recently several new approaches for the genome-scale engineering of E. coli to enhance recombinant protein expression have been developed. These methodologies now enable the generation of optimized E. coli expression strains in a manner analogous to metabolic engineering for the synthesis of low-molecular-weight compounds. In this review, we provide an overview of strain engineering approaches useful for enhancing the expression of hard-to-produce proteins, including heterologous membrane proteins.
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Affiliation(s)
- Tomohiro Makino
- Department of Chemical Engineering, The University of Texas at Austin, 78712, USA
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29
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Zheng DQ, Wu XC, Wang PM, Chi XQ, Tao XL, Li P, Jiang XH, Zhao YH. Drug resistance marker-aided genome shuffling to improve acetic acid tolerance in Saccharomyces cerevisiae. J Ind Microbiol Biotechnol 2010; 38:415-22. [PMID: 20652356 DOI: 10.1007/s10295-010-0784-8] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2010] [Accepted: 07/07/2010] [Indexed: 11/28/2022]
Abstract
Acetic acid existing in a culture medium is one of the most limiting constraints in yeast growth and viability during ethanol fermentation. To improve acetic acid tolerance in Saccharomyces cerevisiae strains, a drug resistance marker-aided genome shuffling approach with higher screen efficiency of shuffled mutants was developed in this work. Through two rounds of genome shuffling of ultraviolet mutants derived from the original strain 308, we obtained a shuffled strain YZ2, which shows significantly faster growth and higher cell viability under acetic acid stress. Ethanol production of YZ2 (within 60 h) was 21.6% higher than that of 308 when 0.5% (v/v) acetic acid was added to fermentation medium. Membrane integrity, higher in vivo activity of the H+-ATPase, and lower oxidative damage after acetic acid treatment are the possible reasons for the acetic acid-tolerance phenotype of YZ2. These results indicated that this novel genome shuffling approach is powerful to rapidly improve the complex traits of industrial yeast strains.
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Affiliation(s)
- Dao-Qiong Zheng
- Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou, 310058 Zhejiang, People's Republic of China
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30
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Zhang Y, Liu JZ, Huang JS, Mao ZW. Genome shuffling of Propionibacterium shermanii for improving vitamin B12 production and comparative proteome analysis. J Biotechnol 2010; 148:139-43. [PMID: 20553774 DOI: 10.1016/j.jbiotec.2010.05.008] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2009] [Revised: 03/20/2010] [Accepted: 05/20/2010] [Indexed: 11/17/2022]
Abstract
Genome shuffling is an efficient approach for the rapid improvement of microbial phenotype. Here we improved vitamin B12 production of Propionibacterium shermanii by genome shuffling based on inactivated protoplast fusion. A genome shuffling strain with titer of vitamin B12 of 2.85 mgl(-1), named Propionibacterium shermanii-F2-3, was obtained. The genome shuffled strain produced about 61% improvement of vitamin B12 over the parent strain after 96 h. Comparative analysis of proteome profile was conducted between Propionibacterium shermanii 17 and F2-3. The expression levels of 38 proteins varied significantly in the genome shuffled strain compared with those in the parent strain. Of these proteins, 22 proteins were up-regulated, 16 proteins were down-regulated. Of the up-regulated proteins, 6 proteins (glutaminyl-tRNA synthetase (GlnS), Delta-aminolevulinic acid dehydratase (HemB), methionine synthase (Meth), riboflavin synthase (RibE), phosphofructo kinase (PfkA) and isocitrate dehydrogenase (Icd) is involved in the vitamin B12 biosynthesis pathway. They may be the key enzymes of vitamin B12 biosynthesis.
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Affiliation(s)
- Ying Zhang
- Biotechnology Research Center and Key Laboratory of Gene Engineering of Ministry of Education, Key laboratory of Biocontrol, Sun Yat-Sen University, Guangzhou 510275, China
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31
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Novel Escherichia coli hybrids with enhanced butanol tolerance. Biotechnol Lett 2010; 32:915-20. [DOI: 10.1007/s10529-010-0247-3] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2009] [Revised: 02/28/2010] [Accepted: 03/04/2010] [Indexed: 11/26/2022]
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32
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Genome shuffling amplifies the carbon source spectrum and improves arachidonic acid production in Diasporangium sp. Enzyme Microb Technol 2009. [DOI: 10.1016/j.enzmictec.2009.08.012] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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33
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Gong J, Zheng H, Wu Z, Chen T, Zhao X. Genome shuffling: Progress and applications for phenotype improvement. Biotechnol Adv 2009; 27:996-1005. [DOI: 10.1016/j.biotechadv.2009.05.016] [Citation(s) in RCA: 109] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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34
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Li Z, Zhang S, Zhang J, Liu M, Liu Z. Vitellogenin is a cidal factor capable of killing bacteria via interaction with lipopolysaccharide and lipoteichoic acid. Mol Immunol 2009; 46:3232-9. [DOI: 10.1016/j.molimm.2009.08.006] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2009] [Revised: 08/04/2009] [Accepted: 08/06/2009] [Indexed: 10/20/2022]
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35
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36
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John RP, Gangadharan D, Madhavan Nampoothiri K. Genome shuffling of Lactobacillus delbrueckii mutant and Bacillus amyloliquefaciens through protoplasmic fusion for L-lactic acid production from starchy wastes. BIORESOURCE TECHNOLOGY 2008; 99:8008-8015. [PMID: 18482834 DOI: 10.1016/j.biortech.2008.03.058] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2008] [Revised: 03/19/2008] [Accepted: 03/20/2008] [Indexed: 05/26/2023]
Abstract
Current study was focused on the development of a non-fastidious lactic acid producing strain having better growth rate, low pH tolerance and good productivity by genome shuffling of a mutant strain of Lactobacillus delbrueckii NCIM 2025 and an amylase producing non-fastidious Bacillus amyloliquefaciens ATCC 23842. After the third cycle of the protoplast fusion, lactic acid production by few fusants was monitored and the best fusant was selected for further studies. Optimization of the important process parameters for lactic acid production was conducted using Plackett-Burman design and response surface methodology. Selected fusant could utilize the liquefied cassava bagasse starch directly with minimum nutrient supplementation for lactic acid production. During validation, 40g/L of lactic acid was obtained ( approximately 96% conversion of starch to lactic acid) by using fusant inoculum (3%, v/v) from 83g/L cassava bagasse (starch content 50% w/w) supplemented with yeast extract and peptone (0.2% each, w/v) and the buffering agent (2% CaCO3, w/v).
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Affiliation(s)
- Rojan P John
- Biotechnology Division, National Institute for Interdesciplinary Science and Technology (Formerly Regional Research Laboratory), CSIR, Trivandrum 695 019, Kerala, India
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37
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Ebersbach G, Briegel A, Jensen GJ, Jacobs-Wagner C. A self-associating protein critical for chromosome attachment, division, and polar organization in caulobacter. Cell 2008; 134:956-68. [PMID: 18805089 DOI: 10.1016/j.cell.2008.07.016] [Citation(s) in RCA: 228] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2007] [Revised: 04/18/2008] [Accepted: 07/11/2008] [Indexed: 10/21/2022]
Abstract
Cell polarization is an integral part of many unrelated bacterial processes. How intrinsic cell polarization is achieved is poorly understood. Here, we provide evidence that Caulobacter crescentus uses a multimeric pole-organizing factor (PopZ) that serves as a hub to concurrently achieve several polarizing functions. During chromosome segregation, polar PopZ captures the ParB*ori complex and thereby anchors sister chromosomes at opposite poles. This step is essential for stabilizing bipolar gradients of a cell division inhibitor and setting up division near midcell. PopZ also affects polar stalk morphogenesis and mediates the polar localization of the morphogenetic and cell cycle signaling proteins CckA and DivJ. Polar accumulation of PopZ, which is central to its polarizing activity, can be achieved independently of division and does not appear to be dictated by the pole curvature. Instead, evidence suggests that localization of PopZ largely relies on PopZ multimerization in chromosome-free regions, consistent with a self-organizing mechanism.
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Affiliation(s)
- Gitte Ebersbach
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT 06520, USA
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