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Bacterial cellulose production, functionalization, and development of hybrid materials using synthetic biology. Polym J 2022. [DOI: 10.1038/s41428-021-00606-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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Buldum G, Mantalaris A. Systematic Understanding of Recent Developments in Bacterial Cellulose Biosynthesis at Genetic, Bioprocess and Product Levels. Int J Mol Sci 2021; 22:ijms22137192. [PMID: 34281246 PMCID: PMC8268586 DOI: 10.3390/ijms22137192] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Revised: 06/28/2021] [Accepted: 06/30/2021] [Indexed: 02/06/2023] Open
Abstract
Engineering biological processes has become a standard approach to produce various commercially valuable chemicals, therapeutics, and biomaterials. Among these products, bacterial cellulose represents major advances to biomedical and healthcare applications. In comparison to properties of plant cellulose, bacterial cellulose (BC) shows distinctive characteristics such as a high purity, high water retention, and biocompatibility. However, low product yield and extensive cultivation times have been the main challenges in the large-scale production of BC. For decades, studies focused on optimization of cellulose production through modification of culturing strategies and conditions. With an increasing demand for BC, researchers are now exploring to improve BC production and functionality at different categories: genetic, bioprocess, and product levels as well as model driven approaches targeting each of these categories. This comprehensive review discusses the progress in BC platforms categorizing the most recent advancements under different research focuses and provides systematic understanding of the progress in BC biosynthesis. The aim of this review is to present the potential of ‘modern genetic engineering tools’ and ‘model-driven approaches’ on improving the yield of BC, altering the properties, and adding new functionality. We also provide insights for the future perspectives and potential approaches to promote BC use in biomedical applications.
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Affiliation(s)
- Gizem Buldum
- Department of Life Sciences, Imperial College London, London SW7 2AZ, UK;
| | - Athanasios Mantalaris
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA
- Correspondence:
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3
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Fricke PM, Klemm A, Bott M, Polen T. On the way toward regulatable expression systems in acetic acid bacteria: target gene expression and use cases. Appl Microbiol Biotechnol 2021; 105:3423-3456. [PMID: 33856535 PMCID: PMC8102297 DOI: 10.1007/s00253-021-11269-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Revised: 03/24/2021] [Accepted: 04/04/2021] [Indexed: 01/06/2023]
Abstract
Acetic acid bacteria (AAB) are valuable biocatalysts for which there is growing interest in understanding their basics including physiology and biochemistry. This is accompanied by growing demands for metabolic engineering of AAB to take advantage of their properties and to improve their biomanufacturing efficiencies. Controlled expression of target genes is key to fundamental and applied microbiological research. In order to get an overview of expression systems and their applications in AAB, we carried out a comprehensive literature search using the Web of Science Core Collection database. The Acetobacteraceae family currently comprises 49 genera. We found overall 6097 publications related to one or more AAB genera since 1973, when the first successful recombinant DNA experiments in Escherichia coli have been published. The use of plasmids in AAB began in 1985 and till today was reported for only nine out of the 49 AAB genera currently described. We found at least five major expression plasmid lineages and a multitude of further expression plasmids, almost all enabling only constitutive target gene expression. Only recently, two regulatable expression systems became available for AAB, an N-acyl homoserine lactone (AHL)-inducible system for Komagataeibacter rhaeticus and an L-arabinose-inducible system for Gluconobacter oxydans. Thus, after 35 years of constitutive target gene expression in AAB, we now have the first regulatable expression systems for AAB in hand and further regulatable expression systems for AAB can be expected. KEY POINTS: • Literature search revealed developments and usage of expression systems in AAB. • Only recently 2 regulatable plasmid systems became available for only 2 AAB genera. • Further regulatable expression systems for AAB are in sight.
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Affiliation(s)
- Philipp Moritz Fricke
- IBG-1: Biotechnology, Institute of Bio- and Geosciences, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Angelika Klemm
- IBG-1: Biotechnology, Institute of Bio- and Geosciences, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Michael Bott
- IBG-1: Biotechnology, Institute of Bio- and Geosciences, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Tino Polen
- IBG-1: Biotechnology, Institute of Bio- and Geosciences, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
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Singh A, Walker KT, Ledesma-Amaro R, Ellis T. Engineering Bacterial Cellulose by Synthetic Biology. Int J Mol Sci 2020; 21:E9185. [PMID: 33276459 PMCID: PMC7730232 DOI: 10.3390/ijms21239185] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Revised: 11/26/2020] [Accepted: 11/28/2020] [Indexed: 02/06/2023] Open
Abstract
Synthetic biology is an advanced form of genetic manipulation that applies the principles of modularity and engineering design to reprogram cells by changing their DNA. Over the last decade, synthetic biology has begun to be applied to bacteria that naturally produce biomaterials, in order to boost material production, change material properties and to add new functionalities to the resulting material. Recent work has used synthetic biology to engineer several Komagataeibacter strains; bacteria that naturally secrete large amounts of the versatile and promising material bacterial cellulose (BC). In this review, we summarize how genetic engineering, metabolic engineering and now synthetic biology have been used in Komagataeibacter strains to alter BC, improve its production and begin to add new functionalities into this easy-to-grow material. As well as describing the milestone advances, we also look forward to what will come next from engineering bacterial cellulose by synthetic biology.
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Affiliation(s)
- Amritpal Singh
- Imperial College Centre for Synthetic Biology, Imperial College London, London SW7 2AZ, UK; (A.S.); (K.T.W.); (R.L.-A.)
- Department of Bioengineering, Imperial College London, London SW7 2AZ, UK
| | - Kenneth T. Walker
- Imperial College Centre for Synthetic Biology, Imperial College London, London SW7 2AZ, UK; (A.S.); (K.T.W.); (R.L.-A.)
- Department of Bioengineering, Imperial College London, London SW7 2AZ, UK
| | - Rodrigo Ledesma-Amaro
- Imperial College Centre for Synthetic Biology, Imperial College London, London SW7 2AZ, UK; (A.S.); (K.T.W.); (R.L.-A.)
- Department of Bioengineering, Imperial College London, London SW7 2AZ, UK
| | - Tom Ellis
- Imperial College Centre for Synthetic Biology, Imperial College London, London SW7 2AZ, UK; (A.S.); (K.T.W.); (R.L.-A.)
- Department of Bioengineering, Imperial College London, London SW7 2AZ, UK
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Jacek P, Dourado F, Gama M, Bielecki S. Molecular aspects of bacterial nanocellulose biosynthesis. Microb Biotechnol 2019; 12:633-649. [PMID: 30883026 PMCID: PMC6559022 DOI: 10.1111/1751-7915.13386] [Citation(s) in RCA: 66] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Revised: 02/03/2019] [Accepted: 02/08/2019] [Indexed: 11/27/2022] Open
Abstract
Bacterial nanocellulose (BNC) produced by aerobic bacteria is a biopolymer with sophisticated technical properties. Although the potential for economically relevant applications is huge, the cost of BNC still limits its application to a few biomedical devices and the edible product Nata de Coco, made available by traditional fermentation methods in Asian countries. Thus, a wider economic relevance of BNC is still dependent on breakthrough developments on the production technology. On the other hand, the development of modified strains able to overproduce BNC with new properties - e.g. porosity, density of fibres crosslinking, mechanical properties, etc. - will certainly allow to overcome investment and cost production issues and enlarge the scope of BNC applications. This review discusses current knowledge about the molecular basis of BNC biosynthesis, its regulations and, finally, presents a perspective on the genetic modification of BNC producers made possible by the new tools available for genetic engineering.
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Affiliation(s)
- Paulina Jacek
- Institute of Technical BiochemistryLodz University of Technology4/10 Stefanowskiego Str90‐924LodzPoland
| | - Fernando Dourado
- Centre of Biological EngineeringUniversity of MinhoCampus de Gualtar4710‐057BragaPortugal
| | - Miguel Gama
- Centre of Biological EngineeringUniversity of MinhoCampus de Gualtar4710‐057BragaPortugal
| | - Stanisław Bielecki
- Institute of Technical BiochemistryLodz University of Technology4/10 Stefanowskiego Str90‐924LodzPoland
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Anderson LA, Islam MA, Prather KLJ. Synthetic biology strategies for improving microbial synthesis of "green" biopolymers. J Biol Chem 2018; 293:5053-5061. [PMID: 29339554 PMCID: PMC5892568 DOI: 10.1074/jbc.tm117.000368] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Polysaccharide-based biopolymers have many material properties relevant to industrial and medical uses, including as drug delivery agents, wound-healing adhesives, and food additives and stabilizers. Traditionally, polysaccharides are obtained from natural sources. Microbial synthesis offers an attractive alternative for sustainable production of tailored biopolymers. Here, we review synthetic biology strategies for select "green" biopolymers: cellulose, alginate, chitin, chitosan, and hyaluronan. Microbial production pathways, opportunities for pathway yield improvements, and advances in microbial engineering of biopolymers in various hosts are discussed. Taken together, microbial engineering has expanded the repertoire of green biological chemistry by increasing the diversity of biobased materials.
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Affiliation(s)
- Lisa A Anderson
- From the Department of Chemical Engineering and Center for Integrative Synthetic Biology (CISB), Massachusetts Institute of Technology, Cambridge, Massachusetts 02139
| | - M Ahsanul Islam
- From the Department of Chemical Engineering and Center for Integrative Synthetic Biology (CISB), Massachusetts Institute of Technology, Cambridge, Massachusetts 02139
| | - Kristala L J Prather
- From the Department of Chemical Engineering and Center for Integrative Synthetic Biology (CISB), Massachusetts Institute of Technology, Cambridge, Massachusetts 02139
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Liu M, Li S, Xie Y, Jia S, Hou Y, Zou Y, Zhong C. Enhanced bacterial cellulose production by Gluconacetobacter xylinus via expression of Vitreoscilla hemoglobin and oxygen tension regulation. Appl Microbiol Biotechnol 2017; 102:1155-1165. [PMID: 29199354 DOI: 10.1007/s00253-017-8680-z] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Accepted: 11/23/2017] [Indexed: 10/18/2022]
Abstract
Oxygen plays a key role during bacterial cellulose (BC) biosynthesis by Gluconacetobacter xylinus. In this study, the Vitreoscilla hemoglobin (VHb)-encoding gene vgb, which has been widely applied to improve cell survival during hypoxia, was heterologously expressed in G. xylinus via the pBla-VHb-122 plasmid. G. xylinus and G. xylinus-vgb + were statically cultured under hypoxic (10 and 15% oxygen tension in the gaseous phase), atmospheric (21%), and oxygen-enriched conditions (40 and 80%) to investigate the effect of oxygen on cell growth and BC production. Irrespective of vgb expression, we found that cell density increased with oxygen tension (10-80%) during the exponential growth phase but plateaued to the same value in the stationary phase. In contrast, BC production was found to significantly increase at lower oxygen tensions. In addition, we found that BC production at oxygen tensions of 10 and 15% was 26.5 and 58.6% higher, respectively, in G. xylinus-vgb + than that in G. xylinus. The maximum BC yield and glucose conversion rate, of 4.3 g/L and 184.7 mg/g, respectively, were observed in G. xylinus-vgb + at an oxygen tension of 15%. Finally, BC characterization suggested that hypoxic conditions enhance BC's mass density, Young's modulus, and thermostability, with G. xylinus-vgb + synthesizing softer BC than G. xylinus under hypoxia as a result of a decreased Young's modulus. These results will facilitate the use of static culture for the production of BC.
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Affiliation(s)
- Miao Liu
- Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, Tianjin University of Science and Technology, Tianjin, 300457, People's Republic of China
| | - Siqi Li
- Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, Tianjin University of Science and Technology, Tianjin, 300457, People's Republic of China
| | - Yongzhen Xie
- Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, Tianjin University of Science and Technology, Tianjin, 300457, People's Republic of China
| | - Shiru Jia
- Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, Tianjin University of Science and Technology, Tianjin, 300457, People's Republic of China
| | - Ying Hou
- Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, Tianjin University of Science and Technology, Tianjin, 300457, People's Republic of China
| | - Yang Zou
- Tianjin Jialihe Livestock Group Co., Ltd, Jin Wei Road, Beichen District, Tianjin, 300402, People's Republic of China
| | - Cheng Zhong
- Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, Tianjin University of Science and Technology, Tianjin, 300457, People's Republic of China.
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Florea M, Hagemann H, Santosa G, Abbott J, Micklem CN, Spencer-Milnes X, de Arroyo Garcia L, Paschou D, Lazenbatt C, Kong D, Chughtai H, Jensen K, Freemont PS, Kitney R, Reeve B, Ellis T. Engineering control of bacterial cellulose production using a genetic toolkit and a new cellulose-producing strain. Proc Natl Acad Sci U S A 2016; 113:E3431-40. [PMID: 27247386 PMCID: PMC4914174 DOI: 10.1073/pnas.1522985113] [Citation(s) in RCA: 109] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Bacterial cellulose is a strong and ultrapure form of cellulose produced naturally by several species of the Acetobacteraceae Its high strength, purity, and biocompatibility make it of great interest to materials science; however, precise control of its biosynthesis has remained a challenge for biotechnology. Here we isolate a strain of Komagataeibacter rhaeticus (K. rhaeticus iGEM) that can produce cellulose at high yields, grow in low-nitrogen conditions, and is highly resistant to toxic chemicals. We achieved external control over its bacterial cellulose production through development of a modular genetic toolkit that enables rational reprogramming of the cell. To further its use as an organism for biotechnology, we sequenced its genome and demonstrate genetic circuits that enable functionalization and patterning of heterologous gene expression within the cellulose matrix. This work lays the foundations for using genetic engineering to produce cellulose-based materials, with numerous applications in basic science, materials engineering, and biotechnology.
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Affiliation(s)
- Michael Florea
- Centre for Synthetic Biology and Innovation, Imperial College London, London SW7 2AZ, United Kingdom; Department of Life Sciences, Imperial College London, London SW7 2AZ, United Kingdom
| | - Henrik Hagemann
- Centre for Synthetic Biology and Innovation, Imperial College London, London SW7 2AZ, United Kingdom; Department of Bioengineering, Imperial College London, London SW7 2AZ, United Kingdom
| | - Gabriella Santosa
- Centre for Synthetic Biology and Innovation, Imperial College London, London SW7 2AZ, United Kingdom; Department of Life Sciences, Imperial College London, London SW7 2AZ, United Kingdom
| | - James Abbott
- Bioinformatics Support Service, Department of Surgery and Cancer, Imperial College London, London SW7 2AZ, United Kingdom; Centre for Integrative Systems Biology and Bioinformatics, Imperial College London, London SW7 2AZ, United Kingdom
| | - Chris N Micklem
- Centre for Synthetic Biology and Innovation, Imperial College London, London SW7 2AZ, United Kingdom; Department of Life Sciences, Imperial College London, London SW7 2AZ, United Kingdom
| | - Xenia Spencer-Milnes
- Centre for Synthetic Biology and Innovation, Imperial College London, London SW7 2AZ, United Kingdom; Department of Life Sciences, Imperial College London, London SW7 2AZ, United Kingdom
| | - Laura de Arroyo Garcia
- Centre for Synthetic Biology and Innovation, Imperial College London, London SW7 2AZ, United Kingdom; Department of Life Sciences, Imperial College London, London SW7 2AZ, United Kingdom
| | - Despoina Paschou
- Centre for Synthetic Biology and Innovation, Imperial College London, London SW7 2AZ, United Kingdom; Department of Bioengineering, Imperial College London, London SW7 2AZ, United Kingdom
| | - Christopher Lazenbatt
- Centre for Synthetic Biology and Innovation, Imperial College London, London SW7 2AZ, United Kingdom; Department of Life Sciences, Imperial College London, London SW7 2AZ, United Kingdom
| | - Deze Kong
- Centre for Synthetic Biology and Innovation, Imperial College London, London SW7 2AZ, United Kingdom; Department of Bioengineering, Imperial College London, London SW7 2AZ, United Kingdom
| | - Haroon Chughtai
- Centre for Synthetic Biology and Innovation, Imperial College London, London SW7 2AZ, United Kingdom; Department of Bioengineering, Imperial College London, London SW7 2AZ, United Kingdom
| | - Kirsten Jensen
- Centre for Synthetic Biology and Innovation, Imperial College London, London SW7 2AZ, United Kingdom; Department of Medicine, Imperial College London, London SW7 2AZ, United Kingdom
| | - Paul S Freemont
- Centre for Synthetic Biology and Innovation, Imperial College London, London SW7 2AZ, United Kingdom; Department of Medicine, Imperial College London, London SW7 2AZ, United Kingdom
| | - Richard Kitney
- Centre for Synthetic Biology and Innovation, Imperial College London, London SW7 2AZ, United Kingdom; Department of Bioengineering, Imperial College London, London SW7 2AZ, United Kingdom
| | - Benjamin Reeve
- Centre for Synthetic Biology and Innovation, Imperial College London, London SW7 2AZ, United Kingdom; Department of Bioengineering, Imperial College London, London SW7 2AZ, United Kingdom
| | - Tom Ellis
- Centre for Synthetic Biology and Innovation, Imperial College London, London SW7 2AZ, United Kingdom; Department of Bioengineering, Imperial College London, London SW7 2AZ, United Kingdom;
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Genome sequence and plasmid transformation of the model high-yield bacterial cellulose producer Gluconacetobacter hansenii ATCC 53582. Sci Rep 2016; 6:23635. [PMID: 27010592 PMCID: PMC4806288 DOI: 10.1038/srep23635] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Accepted: 03/10/2016] [Indexed: 12/27/2022] Open
Abstract
Bacterial cellulose is a strong, highly pure form of cellulose that is used in a range of applications in industry, consumer goods and medicine. Gluconacetobacter hansenii ATCC 53582 is one of the highest reported bacterial cellulose producing strains and has been used as a model organism in numerous studies of bacterial cellulose production and studies aiming to increased cellulose productivity. Here we present a high-quality draft genome sequence for G. hansenii ATCC 53582 and find that in addition to the previously described cellulose synthase operon, ATCC 53582 contains two additional cellulose synthase operons and several previously undescribed genes associated with cellulose production. In parallel, we also develop optimized protocols and identify plasmid backbones suitable for transformation of ATCC 53582, albeit with low efficiencies. Together, these results provide important information for further studies into cellulose synthesis and for future studies aiming to genetically engineer G. hansenii ATCC 53582 for increased cellulose productivity.
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Novel in vivo-degradable cellulose-chitin copolymer from metabolically engineered Gluconacetobacter xylinus. Appl Environ Microbiol 2010; 76:6257-65. [PMID: 20656868 DOI: 10.1128/aem.00698-10] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Despite excellent biocompatibility and mechanical properties, the poor in vitro and in vivo degradability of cellulose has limited its biomedical and biomass conversion applications. To address this issue, we report a metabolic engineering-based approach to the rational redesign of cellular metabolites to introduce N-acetylglucosamine (GlcNAc) residues into cellulosic biopolymers during de novo synthesis from Gluconacetobacter xylinus. The cellulose produced from these engineered cells (modified bacterial cellulose [MBC]) was evaluated and compared with cellulose produced from normal cells (bacterial cellulose [BC]). High GlcNAc content and lower crystallinity in MBC compared to BC make this a multifunctional bioengineered polymer susceptible to lysozyme, an enzyme widespread in the human body, and to rapid hydrolysis by cellulase, an enzyme commonly used in biomass conversion. Degradability in vivo was demonstrated in subcutaneous implants in mice, where modified cellulose was completely degraded within 20 days. We provide a new route toward the production of a family of tailorable modified cellulosic biopolymers that overcome the longstanding limitation associated with the poor degradability of cellulose for a wide range of potential applications.
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Increased mutation frequency in redox-impaired Escherichia coli due to RelA- and RpoS-mediated repression of DNA repair. Appl Environ Microbiol 2010; 76:5463-70. [PMID: 20581184 DOI: 10.1128/aem.00583-10] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Balancing of reducing equivalents is a fundamental issue in bacterial metabolism and metabolic engineering. Mutations in the key metabolic genes ldhA and pflB of Escherichia coli are known to stall anaerobic growth and fermentation due to a buildup of intracellular NADH. We observed that the rate of spontaneous mutation in E. coli BW25113 (DeltaldhA DeltapflB) was an order of magnitude higher than that in wild-type (WT) E. coli BW25113. We hypothesized that the increased mutation frequency was due to an increased NADH/NAD(+) ratio in this strain. Using several redox-impaired strains of E. coli and different redox conditions, we confirmed a significant correlation (P < 0.01) between intracellular-NADH/NAD(+) ratio and mutation frequency. To identify the genetic basis for this relationship, whole-genome transcriptional profiles were compared between BW25113 WT and BW25113 (DeltaldhA DeltapflB). This analysis revealed that the genes involved in DNA repair were expressed at significantly lower levels in BW25113 (DeltaldhA DeltapflB). Direct measurements of the extent of DNA repair in BW25113 (DeltaldhA DeltapflB) subjected to UV exposure confirmed that DNA repair was inhibited. To identify a direct link between DNA repair and intracellular-redox ratio, the stringent-response-regulatory gene relA and the global-stress-response-regulatory gene rpoS were deleted. In both cases, the mutation frequencies were restored to BW25113 WT levels.
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