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Carvalho FM, Azevedo A, Ferreira MM, Mergulhão FJM, Gomes LC. Advances on Bacterial and Fungal Biofilms for the Production of Added-Value Compounds. BIOLOGY 2022; 11:biology11081126. [PMID: 36009752 PMCID: PMC9405441 DOI: 10.3390/biology11081126] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Revised: 07/21/2022] [Accepted: 07/22/2022] [Indexed: 11/24/2022]
Abstract
Simple Summary The production of bio-based materials, including organic acids, antibiotics, enzymes, ethanol, and hydrogen, is generally done by the cultivation of suspended cells rather than using immobilized cells. However, several studies suggest the application of productive biofilms as a reliable alternative for biocatalysis, with many advantages over suspended-growth systems. This review gives an overview of the breakthrough in the application of biofilm platforms for the sustainable production of valuable compounds, with particular insight into the latest advances in the production of recombinant proteins. Productive biofilms are shown to improve production rates and product yields, demonstrating great potential for industrial applications. Abstract In recent years, abundant research has been performed on biofilms for the production of compounds with biotechnological and industrial relevance. The use of biofilm platforms has been seen as a compelling approach to producing fine and bulk chemicals such as organic acids, alcohols, and solvents. However, the production of recombinant proteins using this system is still scarce. Biofilm reactors are known to have higher biomass density, operational stability, and potential for long-term operation than suspended cell reactors. In addition, there is an increasing demand to harness industrial and agricultural wastes and biorefinery residues to improve process sustainability and reduce production costs. The synthesis of recombinant proteins and other high-value compounds is mainly achieved using suspended cultures of bacteria, yeasts, and fungi. This review discusses the use of biofilm reactors for the production of recombinant proteins and other added-value compounds using bacteria and fungi.
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Affiliation(s)
- Fábio M. Carvalho
- LEPABE—Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal; (F.M.C.); (A.A.); (M.M.F.); (F.J.M.M.)
- ALiCE—Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
| | - Ana Azevedo
- LEPABE—Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal; (F.M.C.); (A.A.); (M.M.F.); (F.J.M.M.)
- ALiCE—Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
| | - Marta M. Ferreira
- LEPABE—Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal; (F.M.C.); (A.A.); (M.M.F.); (F.J.M.M.)
- ALiCE—Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
| | - Filipe J. M. Mergulhão
- LEPABE—Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal; (F.M.C.); (A.A.); (M.M.F.); (F.J.M.M.)
- ALiCE—Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
| | - Luciana C. Gomes
- LEPABE—Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal; (F.M.C.); (A.A.); (M.M.F.); (F.J.M.M.)
- ALiCE—Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
- Correspondence:
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Hydrodynamic Effects on Biofilm Development and Recombinant Protein Expression. Microorganisms 2022; 10:microorganisms10050931. [PMID: 35630375 PMCID: PMC9145004 DOI: 10.3390/microorganisms10050931] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 04/21/2022] [Accepted: 04/27/2022] [Indexed: 11/17/2022] Open
Abstract
Hydrodynamics play an important role in the rate of cell attachment and nutrient and oxygen transfer, which can affect biofilm development and the level of recombinant protein production. In the present study, the effects of different flow conditions on the development of Escherichia coli biofilms and the expression of a model recombinant protein (enhanced green fluorescent protein, eGFP) were examined. Planktonic and biofilm cells were grown at two different flow rates in a recirculating flow cell system for 7 days: 255 and 128 L h−1 (corresponding to a Reynolds number of 4600 and 2300, respectively). The fluorometric analysis showed that the specific eGFP production was higher in biofilms than in planktonic cells under both hydrodynamic conditions (3-fold higher for 255 L h−1 and 2-fold higher for 128 L h−1). In the biofilm cells, the percentage of eGFP-expressing cells was on average 52% higher at a flow rate of 255 L h−1. Furthermore, a higher plasmid copy number (PCN) was obtained for the highest flow rate for both planktonic (244 PCN/cell versus 118 PCN/cell) and biofilm cells (43 PCN/cell versus 29 PCN/cell). The results suggested that higher flow velocities promoted eGFP expression in E. coli biofilms.
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Røder HL, Trivedi U, Russel J, Kragh KN, Herschend J, Thalsø-Madsen I, Tolker-Nielsen T, Bjarnsholt T, Burmølle M, Madsen JS. Biofilms can act as plasmid reserves in the absence of plasmid specific selection. NPJ Biofilms Microbiomes 2021; 7:78. [PMID: 34620879 PMCID: PMC8497521 DOI: 10.1038/s41522-021-00249-w] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Accepted: 09/15/2021] [Indexed: 02/06/2023] Open
Abstract
Plasmids facilitate rapid bacterial adaptation by shuttling a wide variety of beneficial traits across microbial communities. However, under non-selective conditions, maintaining a plasmid can be costly to the host cell. Nonetheless, plasmids are ubiquitous in nature where bacteria adopt their dominant mode of life - biofilms. Here, we demonstrate that biofilms can act as spatiotemporal reserves for plasmids, allowing them to persist even under non-selective conditions. However, under these conditions, spatial stratification of plasmid-carrying cells may promote the dispersal of cells without plasmids, and biofilms may thus act as plasmid sinks.
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Affiliation(s)
- Henriette Lyng Røder
- Section of Microbiology, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Urvish Trivedi
- Section of Microbiology, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Jakob Russel
- Section of Microbiology, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Kasper Nørskov Kragh
- Costerton Biofilm Center, Department of Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark.,Department of Clinical Microbiology, University Hospital of Copenhagen, Rigshospitalet, Copenhagen, Denmark
| | - Jakob Herschend
- Section of Microbiology, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Ida Thalsø-Madsen
- Department of Veterinary and Animal Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Tim Tolker-Nielsen
- Costerton Biofilm Center, Department of Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark.,Department of Clinical Microbiology, University Hospital of Copenhagen, Rigshospitalet, Copenhagen, Denmark
| | - Thomas Bjarnsholt
- Costerton Biofilm Center, Department of Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark.,Department of Clinical Microbiology, University Hospital of Copenhagen, Rigshospitalet, Copenhagen, Denmark
| | - Mette Burmølle
- Section of Microbiology, Department of Biology, University of Copenhagen, Copenhagen, Denmark.
| | - Jonas Stenløkke Madsen
- Section of Microbiology, Department of Biology, University of Copenhagen, Copenhagen, Denmark.
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Gomes L, Monteiro G, Mergulhão F. The Impact of IPTG Induction on Plasmid Stability and Heterologous Protein Expression by Escherichia coli Biofilms. Int J Mol Sci 2020; 21:ijms21020576. [PMID: 31963160 PMCID: PMC7013871 DOI: 10.3390/ijms21020576] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Revised: 01/06/2020] [Accepted: 01/13/2020] [Indexed: 11/30/2022] Open
Abstract
This work assesses the effect of chemical induction with isopropyl β-D-1-thiogalactopyranoside (IPTG) on the expression of enhanced green fluorescent protein (eGFP) by planktonic and biofilm cells of Escherichia coli JM109(DE3) transformed with a plasmid containing a T7 promoter. It was shown that induction negatively affected the growth and viability of planktonic cultures, and eGFP production did not increase. Heterologous protein production was not limited by gene dosage or by transcriptional activity. Results suggest that plasmid maintenance at high copy number imposes a metabolic burden that precludes high level expression of the heterologous protein. In biofilm cells, the inducer avoided the overall decrease in the amount of expressed eGFP, although this was not correlated with the gene dosage. Higher specific production levels were always attained with biofilm cells and it seems that while induction of biofilm cells shifts their metabolism towards the maintenance of heterologous protein concentration, in planktonic cells the cellular resources are directed towards plasmid replication and growth.
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Affiliation(s)
- Luciana Gomes
- LEPABE—Department of Chemical Engineering, Faculty of Engineering, University of Porto, 4200-465 Porto, Portugal;
| | - Gabriel Monteiro
- iBB—Institute for Bioengineering and Biosciences, Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal;
| | - Filipe Mergulhão
- LEPABE—Department of Chemical Engineering, Faculty of Engineering, University of Porto, 4200-465 Porto, Portugal;
- Correspondence: ; Tel.: +351-225081668
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Soares A, Azevedo A, Gomes LC, Mergulhão FJ. Recombinant protein expression in biofilms. AIMS Microbiol 2019; 5:232-250. [PMID: 31663059 PMCID: PMC6787351 DOI: 10.3934/microbiol.2019.3.232] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2019] [Accepted: 08/20/2019] [Indexed: 12/22/2022] Open
Abstract
Biofilm research is usually focused on the prevention or control of biofilm formation. Recently, the significance of the biofilm mode of growth in biotechnological applications received increased attention. Since biofilm reactors show many advantages over suspended cell reactors, especially in their higher biomass density and operational stability, bacterial biofilms have emerged as an interesting approach for the expression of specific proteins. Despite the potential of biofilm systems, recombinant protein production using biofilms has been scarcely investigated for the past 25 years. Our group has demonstrated that E. coli biofilms were able to produce a model recombinant protein, the enhanced green fluorescent protein (eGFP), at much higher levels than their planktonic counterparts. Even without optimization of cultivation conditions, an attractive productivity was obtained, indicating that biofilm cultures can be used as an alternative form of high cell density cultivation (HCDC). E. coli remains one of the favorite hosts for recombinant protein production and it has been successfully used in metabolic engineering for the synthesis of high value products. This review presents the advantages and concerns of using biofilms for the production of recombinant proteins and summarizes the different biofilm systems which have been described for this purpose. The relative advantages and disadvantages of the four microbial hosts tested for recombinant protein production in biofilms (two bacteria and two filamentous fungi) are also discussed.
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Affiliation(s)
- Alexandra Soares
- Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
| | - Ana Azevedo
- Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
| | - Luciana C Gomes
- Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
| | - Filipe J Mergulhão
- Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
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Soares A, Gomes LC, Mergulhão FJ. Comparing the Recombinant Protein Production Potential of Planktonic and Biofilm Cells. Microorganisms 2018; 6:E48. [PMID: 29794993 PMCID: PMC6027475 DOI: 10.3390/microorganisms6020048] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Revised: 05/18/2018] [Accepted: 05/21/2018] [Indexed: 11/17/2022] Open
Abstract
Recombinant protein production in bacterial cells is commonly performed using planktonic cultures. However, the natural state for many bacteria is living in communities attached to surfaces forming biofilms. In this work, a flow cell system was used to compare the production of a model recombinant protein (enhanced green fluorescent protein, eGFP) between planktonic and biofilm cells. The fluorometric analysis revealed that when the system was in steady state, the average specific eGFP production from Escherichia coli biofilm cells was 10-fold higher than in planktonic cells. Additionally, epifluorescence microscopy was used to determine the percentage of eGFP-expressing cells in both planktonic and biofilm populations. In steady state, the percentage of planktonic-expressing cells oscillated around 5%, whereas for biofilms eGFP-expressing cells represented on average 21% of the total cell population. Therefore, the combination of fluorometric and microscopy data allowed us to conclude that E. coli biofilm cells can have a higher recombinant protein production capacity when compared to their planktonic counterparts.
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Affiliation(s)
- Alexandra Soares
- LEPABE-Department of Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal.
| | - Luciana Calheiros Gomes
- LEPABE-Department of Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal.
| | - Filipe José Mergulhão
- LEPABE-Department of Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal.
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Gomes L, Mergulhão F. Heterologous protein production in Escherichia coli biofilms: A non-conventional form of high cell density cultivation. Process Biochem 2017. [DOI: 10.1016/j.procbio.2017.03.018] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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8
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Song M, Li Q, Zhang Y, Song J, Shi X, Shi C. Biofilm formation and antibiotic resistance pattern of dominantStaphylococcus aureusclonal lineages in China. J Food Saf 2016. [DOI: 10.1111/jfs.12304] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- Minghui Song
- MOST-USDA Joint Research Center for Food Safety, School of Agriculture and Biology and State Key Laboratory of Microbial Metabolism; Shanghai Jiao Tong University; Shanghai 200240 P. R. China
| | - Qiongqiong Li
- Shanghai Institute for Food and Drug Control; Shanghai 201203 P. R. China
| | - Yi Zhang
- MOST-USDA Joint Research Center for Food Safety, School of Agriculture and Biology and State Key Laboratory of Microbial Metabolism; Shanghai Jiao Tong University; Shanghai 200240 P. R. China
| | - Jinxia Song
- The Affiliated Hospital of Qingdao University; Qingdao 266003 P. R. China
| | - Xianming Shi
- MOST-USDA Joint Research Center for Food Safety, School of Agriculture and Biology and State Key Laboratory of Microbial Metabolism; Shanghai Jiao Tong University; Shanghai 200240 P. R. China
| | - Chunlei Shi
- MOST-USDA Joint Research Center for Food Safety, School of Agriculture and Biology and State Key Laboratory of Microbial Metabolism; Shanghai Jiao Tong University; Shanghai 200240 P. R. China
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9
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C. Gomes L, J. Mergulhão F. Effect of heterologous protein expression on <em>Escherichia coli</em> biofilm formation and biocide susceptibility. AIMS Microbiol 2016. [DOI: 10.3934/microbiol.2016.4.434] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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10
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Ma H, Katzenmeyer KN, Bryers JD. Non-invasive in situ monitoring and quantification of TOL plasmid segregational loss within Pseudomonas putida biofilms. Biotechnol Bioeng 2013; 110:2949-58. [PMID: 23633286 DOI: 10.1002/bit.24953] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2013] [Revised: 04/22/2013] [Accepted: 04/26/2013] [Indexed: 11/06/2022]
Abstract
Methods for the detection of plasmid loss in natural environments have typically relied on replica plating, selective markers and PCR. However, these traditional methods have the limitations of low sensitivity, underestimation of specific cell populations, and lack of insightful data for non-homogeneous environments. We have developed a non-invasive microscopic analytical method to quantify local plasmid segregational loss from a bacterial population within a developing biofilm. The probability of plasmid segregational loss in planktonic and biofilm cultures of Pseudomonas putida carrying the TOL plasmid (pWWO::gfpmut3b) was determined directly in situ, in the absence of any applied selection pressure. Compared to suspended liquid culture, we report that the biofilm mode of growth enhances plasmid segregational loss. Results based on a biofilm-averaged analysis reveal that the probability of plasmid loss in biofilm cultures (0.016 ± 0.004) was significantly greater than that determined in planktonic cultures (0.0052 ± 0.0011). Non-invasive assessments showed that probabilities of plasmid segregational loss at different locations in a biofilm increased dramatically from 0.1% at the substratum surface to 8% at outside layers of biofilm. Results suggest that higher nutrient concentrations and subsequentially higher growth rates resulted in higher probability of plasmid segregational loss at the outer layers of the biofilm.
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Affiliation(s)
- Hongyan Ma
- Department of Bioengineering, University of Washington, Seattle, Washington, 98195
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11
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Non-invasive determination of conjugative transfer of plasmids bearing antibiotic-resistance genes in biofilm-bound bacteria: effects of substrate loading and antibiotic selection. Appl Microbiol Biotechnol 2012; 97:317-28. [PMID: 22669634 DOI: 10.1007/s00253-012-4179-9] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2012] [Revised: 05/13/2012] [Accepted: 05/14/2012] [Indexed: 10/28/2022]
Abstract
Biofilms cause much of all human microbial infections. Attempts to eradicate biofilm-based infections rely on disinfectants and antibiotics. Unfortunately, biofilm bacteria are significantly less responsive to antibiotic stressors than their planktonic counterparts. Sublethal doses of antibiotics can actually enhance biofilm formation. Here, we have developed a non-invasive microscopic image analyses to quantify plasmid conjugation within a developing biofilm. Corroborating destructive samples were analyzed by a cultivation-independent flow cytometry analysis and a selective plate count method to cultivate transconjugants. Increases in substrate loading altered biofilm 3-D architecture and subsequently affected the frequency of plasmid conjugation (decreases at least two times) in the absence of any antibiotic selective pressure. More importantly, donor populations in biofilms exposed to a sublethal dose of kanamycin exhibited enhanced transfer efficiency of plasmids containing the kanamycin resistance gene, up to tenfold. However, when stressed with a different antibiotic, imipenem, transfer of plasmids containing the kan(R+) gene was not enhanced. These preliminary results suggest biofilm bacteria "sense" antibiotics to which they are resistant, which enhances the spread of that resistance. Confocal scanning microscopy coupled with our non-invasive image analysis was able to estimate plasmid conjugative transfer efficiency either averaged over the entire biofilm landscape or locally with individual biofilm clusters.
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Teodósio J, Simões M, Mergulhão F. The influence of nonconjugative Escherichia coli plasmids on biofilm formation and resistance. J Appl Microbiol 2012; 113:373-82. [DOI: 10.1111/j.1365-2672.2012.05332.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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13
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Ma H, Bryers JD. Non-invasive method to quantify local bacterial concentrations in a mixed culture biofilm. J Ind Microbiol Biotechnol 2010; 37:1081-9. [PMID: 20552252 PMCID: PMC3070421 DOI: 10.1007/s10295-010-0756-z] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2010] [Accepted: 05/20/2010] [Indexed: 11/29/2022]
Abstract
To better engineer and analyze beneficial biofilms as well as to develop strategies to control detrimental biofilms (e.g., biomedical device-based infections), it is critical to quantify bacterial species compositions within biofilms. A non-invasive method is described here that determines local and overall bacterial concentrations within a biofilm, using optical microscopy and digital image analysis techniques. The method is based upon a calibration of cell fluorescence to known cell number concentrations and is verified by direct cell counts of destructive samples of cultivated biofilms. Two GFP mutants, each with unique emission colors were used with both epi-fluorescent microscopy and one-photon confocal microscopy to determine local spatial biofilm cell concentrations in pure and mixed-strain biofilms. Our microbial system comprises Pseudomonas putida containing either green fluorescent protein (GFP) or containing the red fluorescent protein (DsRed). Strains expressing a green or red fluorescent protein were detected by two different microscopy methods: epi-fluorescence and single-photon confocal laser scanning microscopy. Overall biofilm cell concentrations determined directly from destructive samples were in good agreement with non-invasive measurements of adherent cell concentrations calculated from the measured "integrated fluorescent density" minus any background fluorescence. Results show the areal cell concentration (cell number/area) determined from non-destructive direct counts in a pure culture or binary-strain biofilm varied with the biofilm depth. Use of this method to estimate local dynamic plasmid segregational loss and plasmid conjugation transfer kinetics will be reported in a subsequent manuscript.
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Affiliation(s)
- Hongyan Ma
- Department of Chemical Engineering, University of Washington, Seattle, WA 98195-1720, USA
| | - James D. Bryers
- Department of Bioengineering, University of Washington, Seattle, WA 98195-1720, USA
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Kobayashi F, Nakamura Y. Effect of repressor gene on stability of bioprocess with continuous conversion of starch into ethanol using recombinant yeast. Biochem Eng J 2004. [DOI: 10.1016/j.bej.2003.08.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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15
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Zhang Z, Moo-Young M, Chisti Y. Plasmid stability in recombinant Saccharomyces cerevisiae. Biotechnol Adv 2004; 14:401-35. [PMID: 14540156 DOI: 10.1016/s0734-9750(96)00033-x] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Because of many advantages, the yeast Saccharomyces cerevisiae is increasingly being employed for expression of recombinant proteins. Usually, hybrid plasmids (shuttle vectors) are employed as carriers to introduce the foreign DNA into the yeast host. Unfortunately, the transformed host often suffers from some kind of instability, tending to lose or alter the foreign plasmid. Construction of stable plasmids, and maintenance of stable expression during extended culture, are some of the major challenges facing commercial production of recombinant proteins. This review examines the factors that affect plasmid stability at the gene, cell, and engineering levels. Strategies for overcoming plasmid loss, and the models for predicting plasmid instability, are discussed. The focus is on S. cerevisiae, but where relevant, examples from the better studied Escherichia coli system are discussed. Compared to free suspension culture, immobilization of cells is particularly effective in improving plasmid retention, hence, immobilized systems are examined in some detail. Immobilized cell systems combine high cell concentrations with enhanced productivity of the recombinant product, thereby offering a potentially attractive production method, particularly when nonselective media are used. Understanding of the stabilizing mechanisms is a prerequisite to any substantial commercial exploitation and improvement of immobilized cell systems.
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Affiliation(s)
- Z Zhang
- Department of Chemical Engineering, University of Waterloo, Waterloo, Ontario, Canada N2L 3Gl
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Affiliation(s)
- R J Lamont
- Department of Oral Biology, University of Washington, Seattle, Washington 98195, USA
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17
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Sharp RR, Bryers JD, Jones WG. Activity and stability of a recombinant plasmid-borne TCE degradative pathway in biofilm cultures. Biotechnol Bioeng 1998; 59:318-27. [PMID: 10099343 DOI: 10.1002/(sici)1097-0290(19980805)59:3<318::aid-bit8>3.0.co;2-e] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The activity and stability of the TCE degradative plasmid TOM31c in the transconjugant host Burkholderia cepacia 17616 was studied in selective and non-selective biofilm cultures. The activity of plasmid TOM31c in biofilm cultures was measured by both TCE degradative studies and the expression of the Tom pathway. Plasmid loss was measured using continuous flow, rotating annular biofilm reactors, and various analytical and microbiological techniques. The probability of plasmid loss in the biofilm cultures was determined using a non-steady-state biofilm plasmid loss model that was derived from a simple mass balance, incorporating results from biofilm growth and plasmid loss studies. The plasmid loss model also utilized Andrew's inhibition growth kinetics and a biofilm detachment term. Results from these biofilm studies were compared to similar studies performed on suspended cultures of Burkholderia cepacia 17616-TOM31c to determine if biofilm growth has a significant effect on either plasmid retention or Tom pathway expression (i.e., TCE degradation rates). Results show that the activity and expression of the Tom pathway measured in biofilm cultures was significantly less than that found in suspended cultures at comparable growth rates. The data obtained from these studies fit the plasmid loss model well, providing plasmid loss probability factors for biofilm cultures that were equivalent to those previously found for suspended cultures. The probability of plasmid loss in the B. cepacia 17616-TOM31c biofilm cultures was equivalent to those found in the suspended cultures. The results indicate that biofilm growth neither helps nor hinders plasmid stability. In both the suspended and the biofilm cultures, plasmid retention and expression could be maintained using selective growth substrates and/or an appropriate plasmid-selective antibiotic. Copyright 1998 John Wiley & Sons, Inc.
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Affiliation(s)
- RR Sharp
- Department of Environmental Engineering, Manhattan College, Riverdale, New York 10475, USA
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18
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Sharp RR, Bryers JD, Jones WG, Shields MS. Activity and stability of a recombinant plasmid-borne TCE degradative pathway in suspended cultures. Biotechnol Bioeng 1998. [DOI: 10.1002/(sici)1097-0290(19980205)57:3<287::aid-bit5>3.0.co;2-d] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Lloyd J, Bunch A. The physiological state of an ethylenogenic Escherichia coli immobilized in hollow-fiber bioreactors. Enzyme Microb Technol 1996. [DOI: 10.1016/0141-0229(95)00077-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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20
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Huang CT, Peretti SW, Bryers JD. Effects of inducer levels on a recombinant bacterial biofilm formation and gene expression. Biotechnol Lett 1994. [DOI: 10.1007/bf00128622] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Huang CT, Peretti SW, Bryers JD. Effects of medium carbon-to-nitrogen ratio on biofilm formation and plasmid stability. Biotechnol Bioeng 1994; 44:329-36. [DOI: 10.1002/bit.260440310] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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22
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Affiliation(s)
- J N Barbotin
- Laboratoire de Génie Cellulaire, Université de Picardie Jules Verne, Amiens, France
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Chen CI, Mueller RF, Griebe T. Kinetic analysis of microbial sulfate reduction bydesulfovibrio desulfuricans in an anaerobic upflow porous media biofilm reactor. Biotechnol Bioeng 1994; 43:267-74. [DOI: 10.1002/bit.260430402] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Abstract
The instability of cell cultures containing plasmid vectors is a major problem in the commercial exploitation of molecular cloning techniques. Plasmid stability is influenced by the nature of the host cell, the type of plasmid and/or environmental conditions. Plasmid encoded properties may confer a selective advantage on the host cell but can be an energy drain due to replication and expression. Stability of recombinant cultures ultimately may be determined by the cost to benefit ratio of plasmid carriage. The relative competition between plasmid containing and plasmid-free or indigenous populations can determine the degree of dominance of recombinant cultures. The use of inocula in biotechnological processes in which dynamic environmental conditions dominate may also result in instabilities resulting from the characteristics of the ecosystem. In such dynamic conditions plasmid stability is just one contribution to culture stability. Strategies to enhance plasmid stability, within such environments, based on manipulation of physiological state of host cells, must consider the responsiveness or plasticity of both cells and populations. The robustness of cells or the responses to stresses or transient environmental conditions can influence the levels of instability detected; for example, instability or mutation in the host genome may lead to enhanced plasmid stability. Competition among subpopulations arising from unstable copy number control may determine the levels of recombinant cells in open versus closed fermenter systems. Thus the ecological competence (ability to survive and compete) of recombinant cells in dynamic or transient environments is fundamental to the understanding of the ultimate dominance or survival of such recombinant cultures and may form the basis of a strategy to enhance or control stability either in fermenter systems or dynamic process environments. The creation of microniches in time and/or space can enhance plasmid stability. Transient operation based on defined environmental stresses or perturbations in fermenter systems or in heterogeneous or dynamic environments found in gel immobilized cultures have resulted in enhanced stability. Spatial organization resulting from immobilization has the additional advantage of regulated cell protection within defined microenvironments and controlled release, depending on the nature of the gel, from these microenvironments or microcosms. This regulation of ecological competence allied to the advantages of microbial cell growth in gel microenvironments combined with the spatial organization (or juxtapositioning of cells, selective agents, nutrients, protectants, etc.) possible through immobilization technology offers new strategies to enhance plasmid and culture stability.
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Affiliation(s)
- A J McLoughlin
- Department of Industrial Microbiology, University College Dublin, Ireland
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