1
|
Paredes-Barrada M, Kopsiaftis P, Claassens NJ, van Kranenburg R. Parageobacillus thermoglucosidasius as an emerging thermophilic cell factory. Metab Eng 2024; 83:39-51. [PMID: 38490636 DOI: 10.1016/j.ymben.2024.03.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Revised: 02/21/2024] [Accepted: 03/05/2024] [Indexed: 03/17/2024]
Abstract
Parageobacillus thermoglucosidasius is a thermophilic and facultatively anaerobic microbe, which is emerging as one of the most promising thermophilic model organisms for metabolic engineering. The use of thermophilic microorganisms for industrial bioprocesses provides the advantages of increased reaction rates and reduced cooling costs for bioreactors compared to their mesophilic counterparts. Moreover, it enables starch or lignocellulose degradation and fermentation to occur at the same temperature in a Simultaneous Saccharification and Fermentation (SSF) or Consolidated Bioprocessing (CBP) approach. Its natural hemicellulolytic capabilities and its ability to convert CO to metabolic energy make P. thermoglucosidasius a potentially attractive host for bio-based processes. It can effectively degrade hemicellulose due to a number of hydrolytic enzymes, carbohydrate transporters, and regulatory elements coded from a genomic cluster named Hemicellulose Utilization (HUS) locus. The growing availability of effective genetic engineering tools in P. thermoglucosidasius further starts to open up its potential as a versatile thermophilic cell factory. A number of strain engineering examples showcasing the potential of P. thermoglucosidasius as a microbial chassis for the production of bulk and fine chemicals are presented along with current research bottlenecks. Ultimately, this review provides a holistic overview of the distinct metabolic characteristics of P. thermoglucosidasius and discusses research focused on expanding the native metabolic boundaries for the development of industrially relevant strains.
Collapse
Affiliation(s)
- Miguel Paredes-Barrada
- Laboratory of Microbiology, Wageningen University, Stippeneng 4, 6708 WE, Wageningen, The Netherlands
| | | | - Nico J Claassens
- Laboratory of Microbiology, Wageningen University, Stippeneng 4, 6708 WE, Wageningen, The Netherlands.
| | - Richard van Kranenburg
- Laboratory of Microbiology, Wageningen University, Stippeneng 4, 6708 WE, Wageningen, The Netherlands; Corbion, Arkelsedijk 46, 4206 AC, Gorinchem, The Netherlands.
| |
Collapse
|
2
|
Zou Y, Ip JCH, Xie JY, Yeung YH, Wei L, Guo Z, Zhang Y, Qiu JW. Dynamic changes in bacterial communities in three species of corals during the 2017 bleaching event in subtropical Hong Kong waters. MARINE POLLUTION BULLETIN 2024; 199:116002. [PMID: 38181470 DOI: 10.1016/j.marpolbul.2023.116002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2023] [Revised: 11/28/2023] [Accepted: 12/26/2023] [Indexed: 01/07/2024]
Abstract
Bacteria play important roles in coral health, yet little is known about the dynamics of coral-associated bacterial communities during coral bleaching. Here, we reported the dynamic changes of bacterial communities in three scleractinian corals (Montipora peltiformis, Pavona decussata and Platygyra carnosa) during and after bleaching through amplicon sequencing. Our results revealed that the bacterial composition and dominant bacteria varied among the three coral species. The higher susceptibility of M. peltiformis to bleaching corresponded to a lower bacterial community diversity, and the dominant Synechococcus shifted in abundance during the bleaching and coral recovery phases. The resilient P. decussata and P. carnosa had higher bacterial diversity and a more similar bacterial composition between the healthy and bleached conditions. Overall, our study reveals the dynamic changes in coral-associated microbial diversity under different conditions, contributing to explaining the differential susceptibility of corals to extreme climate conditions.
Collapse
Affiliation(s)
- Ying Zou
- School of Life and Health Sciences, Hainan University, Haikou, China
| | | | - James Y Xie
- Department of Biology, Hong Kong Baptist University, Hong Kong, China
| | - Yip Hung Yeung
- Department of Biology, Hong Kong Baptist University, Hong Kong, China
| | - Lu Wei
- School of Life and Health Sciences, Hainan University, Haikou, China
| | - Zhiqiang Guo
- School of Life and Health Sciences, Hainan University, Haikou, China
| | - Yanjie Zhang
- School of Life and Health Sciences, Hainan University, Haikou, China.
| | - Jian-Wen Qiu
- Department of Biology, Hong Kong Baptist University, Hong Kong, China.
| |
Collapse
|
3
|
Kurashiki R, Koyama K, Sakaguchi Y, Okumura Y, Ohshiro T, Suzuki H. Development of a thermophilic host-vector system for the production of recombinant proteins at elevated temperatures. Appl Microbiol Biotechnol 2023; 107:7475-7488. [PMID: 37755510 DOI: 10.1007/s00253-023-12805-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Revised: 09/08/2023] [Accepted: 09/18/2023] [Indexed: 09/28/2023]
Abstract
Geobacillus spp. are moderate thermophiles that can efficiently produce recombinant proteins. Considering the protein production exhibited by these species, we searched for robust promoters in Geobacillus kaustophilus HTA426. Transcriptome data revealed that several genes were highly expressed during the proliferative phase; their promoters were characterized using reporter assays with Venus fluorescent protein (VFP). The results suggested that the cspD promoter (PcspD) directed robust vfp expression at 60°C in G. kaustophilus. Although cspD potentially encodes a cold-shock protein, PcspD functioned at elevated temperatures. The promoter strongly functioned even in Escherichia coli; this prevented the cloning of some genes (e.g., vfp) downstream of it on a plasmid vector via E. coli-based genetic manipulation. Consequently, we generated a mutated PcspD that functioned inefficiently in E. coli and constructed the pGKE124 plasmid using the mutant promoter. The plasmid could carry vfp in E. coli and afford the production of VFP in G. kaustophilus at a yield of 390 mg/L. pGKE124 directed a similar production in other thermophilic species; the highest yield was observed in Geobacillus thermodenitrificans K1041. Several proteins could be produced using a system involving G. thermodenitrificans K1041 and pGKE124. Notably, the extracellular production of xylanase at a yield of 1 g/L was achieved using this system. Although the leaky production of nonsecretory proteins was observed, we developed a simple process to collectively purify recombinant proteins from the intracellular and extracellular fractions. The findings presented there propose an effective host-vector system for the production of recombinant proteins at elevated temperatures. KEY POINTS: • A thermophilic system to produce recombinant proteins was constructed. • The system produced diverse proteins using inexpensive media at elevated temperatures. • The system produced an extracellular protein at a yield of 1 g/L of culture.
Collapse
Affiliation(s)
- Ryota Kurashiki
- Department of Engineering, Graduate School of Sustainability Science, Tottori University, 4-101 Koyama-Minami, Tottori, 680-8552, Japan
| | - Kosuke Koyama
- Department of Engineering, Graduate School of Sustainability Science, Tottori University, 4-101 Koyama-Minami, Tottori, 680-8552, Japan
| | - Yukina Sakaguchi
- Faculty of Engineering, Tottori University, 4-101 Koyama-Minami, Tottori, 680-8552, Japan
| | - Yuta Okumura
- Department of Engineering, Graduate School of Sustainability Science, Tottori University, 4-101 Koyama-Minami, Tottori, 680-8552, Japan
| | - Takashi Ohshiro
- Faculty of Engineering, Tottori University, 4-101 Koyama-Minami, Tottori, 680-8552, Japan
- Center for Research on Green Sustainable Chemistry, Tottori University, 4-101 Koyama-Minami, Tottori, 680-8552, Japan
| | - Hirokazu Suzuki
- Faculty of Engineering, Tottori University, 4-101 Koyama-Minami, Tottori, 680-8552, Japan.
- Center for Research on Green Sustainable Chemistry, Tottori University, 4-101 Koyama-Minami, Tottori, 680-8552, Japan.
| |
Collapse
|
4
|
Sheng L, Madika A, Lau MSH, Zhang Y, Minton NP. Metabolic engineering for the production of acetoin and 2,3-butanediol at elevated temperature in Parageobacillus thermoglucosidasius NCIMB 11955. Front Bioeng Biotechnol 2023; 11:1191079. [PMID: 37200846 PMCID: PMC10185769 DOI: 10.3389/fbioe.2023.1191079] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Accepted: 04/20/2023] [Indexed: 05/20/2023] Open
Abstract
The current climate crisis has emphasised the need to achieve global net-zero by 2050, with countries being urged to set considerable emission reduction targets by 2030. Exploitation of a fermentative process that uses a thermophilic chassis can represent a way to manufacture chemicals and fuels through more environmentally friendly routes with a net reduction in greenhouse gas emissions. In this study, the industrially relevant thermophile Parageobacillus thermoglucosidasius NCIMB 11955 was engineered to produce 3-hydroxybutanone (acetoin) and 2,3-butanediol (2,3-BDO), organic compounds with commercial applications. Using heterologous acetolactate synthase (ALS) and acetolactate decarboxylase (ALD) enzymes, a functional 2,3-BDO biosynthetic pathway was constructed. The formation of by-products was minimized by the deletion of competing pathways surrounding the pyruvate node. Redox imbalance was addressed through autonomous overexpression of the butanediol dehydrogenase and by investigating appropriate aeration levels. Through this, we were able to produce 2,3-BDO as the predominant fermentation metabolite, with up to 6.6 g/L 2,3-BDO (0.33 g/g glucose) representing 66% of the theoretical maximum at 50°C. In addition, the identification and subsequent deletion of a previously unreported thermophilic acetoin degradation gene (acoB1) resulted in enhanced acetoin production under aerobic conditions, producing 7.6 g/L (0.38 g/g glucose) representing 78% of the theoretical maximum. Furthermore, through the generation of a ΔacoB1 mutant and by testing the effect of glucose concentration on 2,3-BDO production, we were able to produce 15.6 g/L of 2,3-BDO in media supplemented with 5% glucose, the highest titre of 2,3-BDO produced in Parageobacillus and Geobacillus species to date.
Collapse
Affiliation(s)
- Lili Sheng
- Clostridia Research Group, BBSRC/EPSRC Synthetic Biology Research Centre (SBRC), School of Life Sciences, Biodiscovery Institute, The University of Nottingham, Nottingham, United Kingdom
| | - Abubakar Madika
- Clostridia Research Group, BBSRC/EPSRC Synthetic Biology Research Centre (SBRC), School of Life Sciences, Biodiscovery Institute, The University of Nottingham, Nottingham, United Kingdom
- Department of Microbiology, Faculty of Life Sciences, Ahmadu Bello University, Zaria, Nigeria
| | - Matthew S. H. Lau
- Clostridia Research Group, BBSRC/EPSRC Synthetic Biology Research Centre (SBRC), School of Life Sciences, Biodiscovery Institute, The University of Nottingham, Nottingham, United Kingdom
| | - Ying Zhang
- Clostridia Research Group, BBSRC/EPSRC Synthetic Biology Research Centre (SBRC), School of Life Sciences, Biodiscovery Institute, The University of Nottingham, Nottingham, United Kingdom
| | - Nigel P. Minton
- Clostridia Research Group, BBSRC/EPSRC Synthetic Biology Research Centre (SBRC), School of Life Sciences, Biodiscovery Institute, The University of Nottingham, Nottingham, United Kingdom
- NIHR Nottingham Biomedical Research Centre, Nottingham University Hospitals NHS Trust, The University of Nottingham, Nottingham, United Kingdom
- *Correspondence: Nigel P. Minton,
| |
Collapse
|
5
|
Madika A, Spencer J, Lau MS, Sheng L, Zhang Y, Minton NP. pMTL60000: A modular plasmid vector series for Parageobacillus thermoglucosidasius strain engineering. J Microbiol Methods 2022; 202:106600. [DOI: 10.1016/j.mimet.2022.106600] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Revised: 10/07/2022] [Accepted: 10/09/2022] [Indexed: 12/27/2022]
|
6
|
New Platform for Screening Genetic Libraries at Elevated Temperatures: Biological and Genomic Information and Genetic Tools of Geobacillus thermodenitrificans K1041. Appl Environ Microbiol 2022; 88:e0105122. [PMID: 36069579 PMCID: PMC9499010 DOI: 10.1128/aem.01051-22] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Geobacillus thermodenitrificans K1041 is an unusual thermophile that is highly transformable via electroporation, making it a promising host for screening genetic libraries at elevated temperatures. In this study, we determined its biological properties, draft genome sequence, and effective vectors and also optimized the electroporation procedures in an effort to enhance its utilization. The organism exhibited swarming motility but not detectable endospore formation, and growth was rapid at 60°C under neutral and relatively low-salt conditions. Although the cells showed negligible acceptance of shuttle plasmids from general strains of Escherichia coli, methylation-controlled plasmids from dam mutant strains were efficiently accepted, suggesting circumvention of a restriction-modification system in G. thermodenitrificans K1041. We optimized the electroporation procedure to achieve efficiencies of 103 to 105 CFU/μg for five types of plasmids, which exhibited the different copy numbers and segregational stabilities in G. thermodenitrificans K1041. Some sets of plasmids were compatible. Moreover, we observed substantial plasmid-directed production of heterologous proteins in the intracellular or extracellular environments. Our successful construction of a library of promoter mutants using K1041 cells as hosts and subsequent screening at elevated temperatures to identify improved promoters revealed that G. thermodenitrificans K1041 was practical as a library host. The draft genomic sequence of the organism contained 3,384 coding genes, including resA and mcrB genes, which are involved in restriction-modification systems. Further examination revealed that in-frame deletions of resA increased transformation efficiencies, but mcrB deletion had no effect. The ΔresA mutant exhibited transformation efficiencies of >105 CFU/μg for some plasmids. IMPORTANCE Geobacillus thermodenitrificans K1041 has yet to be fully characterized. Although it is transformable via electroporation, it rarely accepts Escherichia coli-derived plasmids. This study clarified the biological and genomic properties of G. thermodenitrificans K1041. Additionally, we developed an electroporation procedure resulting in efficient acceptance of E. coli-derived plasmids. This procedure produced transformants using small amounts of plasmids immediately after the ligation reaction. Thus, G. thermodenitrificans K1041 was identified as a host for screening promoter mutants at elevated temperatures. Furthermore, because this strain efficiently produced heterologous proteins, it could serve as a host for screening thermostable proteins encoded in random mutant libraries or metagenomes. We also generated a ΔresA mutant that exhibited transformation efficiencies of >105 CFU/μg, which were highest in cases of electroporation-based transformation of Geobacillus spp. with E. coli-derived plasmids. Our findings provide a new platform for screening diverse genetic libraries at elevated temperatures.
Collapse
|
7
|
Le Y, Sun J. CRISPR/Cas genome editing systems in thermophiles: Current status, associated challenges, and future perspectives. ADVANCES IN APPLIED MICROBIOLOGY 2022; 118:1-30. [PMID: 35461662 DOI: 10.1016/bs.aambs.2022.02.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Thermophiles, offering an attractive and unique platform for a broad range of applications in biofuels and environment protections, have received a significant attention and growing interest from academy and industry. However, the exploration and exploitation of thermophilic organisms have been hampered by the lack of a powerful genome manipulation tool to improve production efficiency. At current, the clustered Regularly Interspaced Short Palindromic Repeat (CRISPR)/CRISPR associated (Cas) system has been successfully exploited as a competent, simplistic, and powerful tool for genome engineering both in eukaryotes and prokaryotes. Indeed, with the significant efforts made in recent years, some thermostable Cas9 proteins have been well identified and characterized and further, some thermostable Cas9-based editing tools have been successfully established in some representative obligate thermophiles. In this regard, we reviewed the current status and its progress in CRISPR/Cas-based genome editing system towards a variety of thermophilic organisms. Despite the potentials of these progresses, multiple factors/barriers still have to be overcome and optimized for improving its editing efficiency in thermophiles. Some insights into the roles of thermostable CRISPR/Cas technologies for the metabolic engineering of thermophiles as a thermophilic microbial cell factory were also fully analyzed and discussed.
Collapse
Affiliation(s)
- Yilin Le
- Biofuels institute, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, Jiangsu, PR China.
| | - Jianzhong Sun
- Biofuels institute, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, Jiangsu, PR China.
| |
Collapse
|
8
|
Ganguly J, Martin-Pascual M, Montiel González D, Bulut A, Vermeulen B, Tjalma I, Vidaki A, van Kranenburg R. Breaking the Restriction Barriers and Applying CRISPRi as a Gene Silencing Tool in Pseudoclostridium thermosuccinogenes. Microorganisms 2022; 10:698. [PMID: 35456750 PMCID: PMC9044749 DOI: 10.3390/microorganisms10040698] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Revised: 03/15/2022] [Accepted: 03/16/2022] [Indexed: 12/10/2022] Open
Abstract
Pseudoclostridium thermosuccinogenes is a thermophilic bacterium capable of producing succinate from lignocellulosic-derived sugars and has the potential to be exploited as a platform organism. However, exploitation of P. thermosuccinogenes has been limited partly due to the genetic inaccessibility and lack of genome engineering tools. In this study, we established the genetic accessibility for P. thermosuccinogenes DSM 5809. By overcoming restriction barriers, transformation efficiencies of 102 CFU/µg plasmid DNA were achieved. To this end, the plasmid DNA was methylated in vivo when transformed into an engineered E. coli HST04 strain expressing three native methylation systems of the thermophile. This protocol was used to introduce a ThermodCas9-based CRISPRi tool targeting the gene encoding malic enzyme in P. thermosuccinogenes, demonstrating the principle of gene silencing. This resulted in 75% downregulation of its expression and had an impact on the strain's fermentation profile. Although the details of the functioning of the restriction modification systems require further study, in vivo methylation can already be applied to improve transformation efficiency of P. thermosuccinogenes. Making use of the ThermodCas9-based CRISPRi, this is the first example demonstrating that genetic engineering in P. thermosuccinogenes is feasible and establishing the way for metabolic engineering of this bacterium.
Collapse
Affiliation(s)
| | - Maria Martin-Pascual
- Laboratory of Microbiology, Wageningen University and Research, 6708 WE Wageningen, The Netherlands; (M.M.-P.); (B.V.); (I.T.)
| | - Diego Montiel González
- Department of Genetic Identification, Erasmus MC University Medical Center Rotterdam, 3015 GD Rotterdam, The Netherlands; (D.M.G.); (A.V.)
| | - Alkan Bulut
- Fontys University of Applied Sciences, 5612 AR Eindhoven, The Netherlands;
| | - Bram Vermeulen
- Laboratory of Microbiology, Wageningen University and Research, 6708 WE Wageningen, The Netherlands; (M.M.-P.); (B.V.); (I.T.)
| | - Ivo Tjalma
- Laboratory of Microbiology, Wageningen University and Research, 6708 WE Wageningen, The Netherlands; (M.M.-P.); (B.V.); (I.T.)
| | - Athina Vidaki
- Department of Genetic Identification, Erasmus MC University Medical Center Rotterdam, 3015 GD Rotterdam, The Netherlands; (D.M.G.); (A.V.)
| | - Richard van Kranenburg
- Corbion, 4206 AC Gorinchem, The Netherlands;
- Laboratory of Microbiology, Wageningen University and Research, 6708 WE Wageningen, The Netherlands; (M.M.-P.); (B.V.); (I.T.)
| |
Collapse
|
9
|
Mol V, Bennett M, Sánchez BJ, Lisowska BK, Herrgård MJ, Nielsen AT, Leak DJ, Sonnenschein N. Genome-scale metabolic modeling of P. thermoglucosidasius NCIMB 11955 reveals metabolic bottlenecks in anaerobic metabolism. Metab Eng 2021; 65:123-134. [PMID: 33753231 DOI: 10.1016/j.ymben.2021.03.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Accepted: 03/01/2021] [Indexed: 12/27/2022]
Abstract
Parageobacillus thermoglucosidasius represents a thermophilic, facultative anaerobic bacterial chassis, with several desirable traits for metabolic engineering and industrial production. To further optimize strain productivity, a systems level understanding of its metabolism is needed, which can be facilitated by a genome-scale metabolic model. Here, we present p-thermo, the most complete, curated and validated genome-scale model (to date) of Parageobacillus thermoglucosidasius NCIMB 11955. It spans a total of 890 metabolites, 1175 reactions and 917 metabolic genes, forming an extensive knowledge base for P. thermoglucosidasius NCIMB 11955 metabolism. The model accurately predicts aerobic utilization of 22 carbon sources, and the predictive quality of internal fluxes was validated with previously published 13C-fluxomics data. In an application case, p-thermo was used to facilitate more in-depth analysis of reported metabolic engineering efforts, giving additional insight into fermentative metabolism. Finally, p-thermo was used to resolve a previously uncharacterised bottleneck in anaerobic metabolism, by identifying the minimal required supplemented nutrients (thiamin, biotin and iron(III)) needed to sustain anaerobic growth. This highlights the usefulness of p-thermo for guiding the generation of experimental hypotheses and for facilitating data-driven metabolic engineering, expanding the use of P. thermoglucosidasius as a high yield production platform.
Collapse
Affiliation(s)
- Viviënne Mol
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Martyn Bennett
- The Department of Biology & Biochemistry, University of Bath, Claverton Down, Bath, BA2 7AY, United Kingdom; The Centre for Sustainable Chemical Technologies (CSCT), University of Bath, Claverton Down, Bath, BA2 7AY, United Kingdom
| | - Benjamín J Sánchez
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kongens Lyngby, Denmark; Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Beata K Lisowska
- The Department of Biology & Biochemistry, University of Bath, Claverton Down, Bath, BA2 7AY, United Kingdom
| | - Markus J Herrgård
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kongens Lyngby, Denmark; BioInnovation Institute, Copenhagen N, Denmark
| | - Alex Toftgaard Nielsen
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kongens Lyngby, Denmark.
| | - David J Leak
- The Department of Biology & Biochemistry, University of Bath, Claverton Down, Bath, BA2 7AY, United Kingdom; The Centre for Sustainable Chemical Technologies (CSCT), University of Bath, Claverton Down, Bath, BA2 7AY, United Kingdom.
| | - Nikolaus Sonnenschein
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark.
| |
Collapse
|
10
|
Genomic and Transcriptome Analyses of a Thermophilic Bacterium Geobacillus stearothermophilus B5 Isolated from Compost Reveal Its Enzymatic Basis for Lignocellulose Degradation. Microorganisms 2020; 8:microorganisms8091357. [PMID: 32899798 PMCID: PMC7564440 DOI: 10.3390/microorganisms8091357] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Revised: 09/01/2020] [Accepted: 09/03/2020] [Indexed: 02/02/2023] Open
Abstract
A lignocellulose-degrading strain isolated from thermophilic compost was identified as Geobacillus stearothermophilus B5, and found able to secrete considerable amounts of enzymes at optimal temperature (60 °C) and pH (7.5). One circular contig of 3.37 Mbp was assembled from raw data, and 3371 protein-coding genes were predicted. Clusters of orthologous groups (COG) analysis revealed various genes with functions in polymeric substrate degradation, especially for Carbohydrate Active enZymes (CAZymes), such as glycoside hydrolases (GHs) and glycosyl transferases (GTs). Furthermore, the transcriptional responses of B5 at different temperatures—with rice straw provided as the sole carbon source—were analyzed. The results revealed that B5 could resist high temperature by upregulating heat shock proteins (HSPs), enhancing protein synthesis, and decreasing carbon catabolism. Briefly, B5 possesses the ability of lignocellulose degradation, and might be considered a potential inoculant for improving composting efficiency.
Collapse
|
11
|
Pan-Genome Analyses of Geobacillus spp. Reveal Genetic Characteristics and Composting Potential. Int J Mol Sci 2020; 21:ijms21093393. [PMID: 32403359 PMCID: PMC7246994 DOI: 10.3390/ijms21093393] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Revised: 05/06/2020] [Accepted: 05/06/2020] [Indexed: 12/27/2022] Open
Abstract
The genus Geobacillus is abundant in ecological diversity and is also well-known as an authoritative source for producing various thermostable enzymes. Although it is clear now that Geobacillus evolved from Bacillus, relatively little knowledge has been obtained regarding its evolutionary mechanism, which might also contribute to its ecological diversity and biotechnology potential. Here, a statistical comparison of thirty-two Geobacillus genomes was performed with a specific focus on pan- and core genomes. The pan-genome of this set of Geobacillus strains contained 14,913 genes, and the core genome contained 940 genes. The Clusters of Orthologous Groups (COG) and Carbohydrate-Active Enzymes (CAZymes) analysis revealed that the Geobacillus strains had huge potential industrial application in composting for agricultural waste management. Detailed comparative analyses showed that basic functional classes and housekeeping genes were conserved in the core genome, while genes associated with environmental interaction or energy metabolism were more enriched in the pan-genome. Therefore, the evolution of Geobacillus seems to be guided by environmental parameters. In addition, horizontal gene transfer (HGT) events among different Geobacillus species were detected. Altogether, pan-genome analysis was a useful method for detecting the evolutionary mechanism, and Geobacillus’ evolution was directed by the environment and HGT events.
Collapse
|
12
|
Zhou J, Lian J, Rao CV. Metabolic engineering of Parageobacillus thermoglucosidasius for the efficient production of (2R, 3R)-butanediol. Appl Microbiol Biotechnol 2020; 104:4303-4311. [PMID: 32221689 DOI: 10.1007/s00253-020-10553-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 03/02/2020] [Accepted: 03/15/2020] [Indexed: 11/27/2022]
Abstract
High-temperature fermentation using thermophilic microorganisms may provide cost-effective processes for the industrial production of fuels and chemicals, due to decreased hygiene and cooling costs. In the present study, the genetically trackable thermophile Parageobacillus thermoglucosidasius DSM2542T was engineered to produce (2R, 3R)-butanediol (R-BDO), a valuable chemical with broad industrial applications. The R-BDO biosynthetic pathway was optimized by testing different combinations of pathway enzymes, with acetolactate synthase (AlsS) from Bacillus subtilis and acetolactate decarboxylase (AlsD) from Streptococcus thermophilus yielding the highest production in P. thermoglucosidasius DSM2542T. Following fermentation condition optimization, shake flask fermentation at 55 °C resulted in the production of 7.2 g/L R-BDO with ~ 72% theoretical yield. This study details the microbial production of R-BDO at the highest fermentation temperature reported to date and demonstrates that P. thermoglucosidasius DSM2542T is a promising cell factory for the production of fuels and chemicals using high-temperature fermentation.
Collapse
Affiliation(s)
- Jiewen Zhou
- Department of Chemical and Biomolecular Engineering, Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
- Hangzhou Zhongmei Huadong Pharmaceutical Co., Ltd, 866 Moganshan Road, Hangzhou, 310011, China
| | - Jiazhang Lian
- Department of Chemical and Biomolecular Engineering, Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
- College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Christopher V Rao
- Department of Chemical and Biomolecular Engineering, Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.
| |
Collapse
|
13
|
Kurashiki R, Mizuno T, Murata K, Ohshiro T, Suzuki H. A plasmid vector that directs hyperproduction of recombinant proteins in the thermophiles Geobacillus species. Extremophiles 2019; 24:147-156. [PMID: 31701242 DOI: 10.1007/s00792-019-01142-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Accepted: 10/23/2019] [Indexed: 11/24/2022]
Abstract
Geobacillus spp. are moderate thermophiles that have great potential for use in diverse applications. For effective utilization of the species, genetic tools have been extensively studied; however, an overexpression vector remains to be developed. Here we constructed a plasmid vector that can shuttle between Escherichia coli and Geobacillus spp., and which contained a maltose-inducible promoter from Geobacillus kaustophilus HTA426. Although the vector (termed pGKE119) was originally designed for basal gene expression, it surprisingly directed robust protein production in G. kaustophilus. Protein production essentially occurred in an auto-inducible manner without maltose; however, some proteins were produced more efficiently in the presence of maltose. Although the productivity was affected by culture conditions, three proteins were successfully produced with abundance ratios of 12-27% (on a total protein basis) and yields of 77-170 mg (per L culture). pGKE119 directed substantial protein production even in Geobacillus subterraneus, Geobacillus thermoglucosidasius, and Geobacillus thermoleovorans. This suggests that pGKE119 can use a range of Geobacillus spp. as hosts and widely expand their genetic toolbox. Because Geobacillus spp. are highly proliferative bacteria that are distinct from organisms used as protein production hosts, pGKE119 may also provide a novel platform for hyperproduction of recombinant proteins.
Collapse
Affiliation(s)
- Ryota Kurashiki
- Department of Engineering, Graduate School of Sustainability Science, Tottori University, 4-101 Koyama-Minami, Tottori, 680-8552, Japan
| | - Tatsuki Mizuno
- Department of Chemistry and Biotechnology, Graduate School of Engineering, Tottori University, 4-101 Koyama-Minami, Tottori, 680-8552, Japan
| | - Kurumi Murata
- Faculty of Engineering, Tottori University, 4-101 Koyama-Minami, Tottori, 680-8552, Japan
| | - Takashi Ohshiro
- Faculty of Engineering, Tottori University, 4-101 Koyama-Minami, Tottori, 680-8552, Japan.,Center for Research on Green Sustainable Chemistry, Tottori University, 4-101 Koyama-Minami, Tottori, 680-8552, Japan
| | - Hirokazu Suzuki
- Faculty of Engineering, Tottori University, 4-101 Koyama-Minami, Tottori, 680-8552, Japan. .,Center for Research on Green Sustainable Chemistry, Tottori University, 4-101 Koyama-Minami, Tottori, 680-8552, Japan.
| |
Collapse
|
14
|
Bashir Z, Sheng L, Anil A, Lali A, Minton NP, Zhang Y. Engineering Geobacillus thermoglucosidasius for direct utilisation of holocellulose from wheat straw. BIOTECHNOLOGY FOR BIOFUELS 2019; 12:199. [PMID: 31452680 PMCID: PMC6701081 DOI: 10.1186/s13068-019-1540-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Accepted: 08/06/2019] [Indexed: 05/29/2023]
Abstract
BACKGROUND A consolidated bioprocessing (CBP), where lignocellulose is converted into the desired product(s) in a single fermentative step without the addition of expensive degradative enzymes, represents the ideal solution of renewable routes to chemicals and fuels. Members of the genus Geobacillus are able to grow at elevated temperatures and are able to utilise a wide range of oligosaccharides derived from lignocellulose. This makes them ideally suited to the development of CBP. RESULTS In this study, we engineered Geobacillus thermoglucosidasius NCIMB 11955 to utilise lignocellulosic biomass, in the form of nitric acid/ammonia treated wheat straw to which expensive hydrolytic enzymes had not been added. Two different strains, BZ9 and BZ10, were generated by integrating the cglT (β-1,4-glucosidase) gene from Thermoanaerobacter brockii into the genome, and localising genes encoding different cellulolytic enzymes on autonomous plasmids. The plasmid of strain BZ10 carried a synthetic cellulosomal operon comprising the celA (Endoglucanase A) gene from Clostridium thermocellum and cel6B (Exoglucanase) from Thermobifida fusca; whereas, strain BZ9 contained a plasmid encoding the celA (multidomain cellulase) gene from Caldicellulosiruptor bescii. All of the genes were successfully expressed, and their encoded products secreted in a functionally active form, as evidenced by their detection in culture supernatants by Western blotting and enzymatic assay. In the case of the C. bescii CelA enzyme, this is one of the first times that the heterologous production of this multi-functional enzyme has been achieved in a heterologous host. Both strains (BZ9 and BZ10) exhibited improved growth on pre-treated wheat straw, achieving a higher final OD600 and producing greater numbers of viable cells. To demonstrate that cellulosic ethanol can be produced directly from lignocellulosic biomass by a single organism, we established our consortium of hydrolytic enzymes in a previously engineered ethanologenic G. thermoglucosidasius strain, LS242. We observed approximately twofold and 1.6-fold increase in ethanol production in the recombinant G. thermoglucosidasius equivalent to BZ9 and BZ10, respectively, compared to G. thermoglucosidasius LS242 strain at 24 h of growth. CONCLUSION We engineered G. thermoglucosidasius to utilise a real-world lignocellulosic biomass substrate and demonstrated that cellulosic ethanol can be produced directly from lignocellulosic biomass in one step. Direct conversion of biomass into desired products represents a new paradigm for CBP, offering the potential for carbon neutral, cost-effective production of sustainable chemicals and fuels.
Collapse
Affiliation(s)
- Zeenat Bashir
- Clostridia Research Group, BBSRC/EPSRC Synthetic Biology Research Centre (SBRC), School of Life Sciences, University of Nottingham, University Park, Nottingham, NG7 2RD UK
| | - Lili Sheng
- Clostridia Research Group, BBSRC/EPSRC Synthetic Biology Research Centre (SBRC), School of Life Sciences, University of Nottingham, University Park, Nottingham, NG7 2RD UK
| | - Annamma Anil
- DBT-ICT Centre for Energy Biosciences, Institute of Chemical Technology, Nathalal Parikh Marg, Mumbai, 400019 India
| | - Arvind Lali
- DBT-ICT Centre for Energy Biosciences, Institute of Chemical Technology, Nathalal Parikh Marg, Mumbai, 400019 India
| | - Nigel P. Minton
- Clostridia Research Group, BBSRC/EPSRC Synthetic Biology Research Centre (SBRC), School of Life Sciences, University of Nottingham, University Park, Nottingham, NG7 2RD UK
| | - Ying Zhang
- Clostridia Research Group, BBSRC/EPSRC Synthetic Biology Research Centre (SBRC), School of Life Sciences, University of Nottingham, University Park, Nottingham, NG7 2RD UK
| |
Collapse
|
15
|
Wade Y, Daniel RA, Leak DJ. Heterologous Microcompartment Assembly in Bacillaceae: Establishing the Components Necessary for Scaffold Formation. ACS Synth Biol 2019; 8:1642-1654. [PMID: 31242391 DOI: 10.1021/acssynbio.9b00155] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Bacterial microcompartments (BMCs) are organelles that host specific biochemical reactions for both anabolic and catabolic functions. Engineered morphologically diverse BMCs bearing heterologous enzymatic pathways have shown enhanced productivity for commodity chemicals, which makes BMCs an important focus for metabolic engineering. Gaining control of BMC assembly and incorporation of a heterologous enzymatic cargo has yet to be achieved in thermophiles. Herein, we address this by first conducting a detailed bioinformatic analysis of the propanediol utilization (pdu) operon in the thermophile Parageobacillus thermoglucosidasius. We then demonstrated, in vivo, the ability to assemble the native BMCs at an elevated temperature of 60 °C. Heterologous expression of Pdu shell proteins from P. thermoglucosidasius in Bacillus subtilis resulted in the assembly of a single tubular BMC with an average length of 1.4 μm; BMCs assembled after a 20 min induction of expression of the shell operons. Moreover, we show that it is possible to target the monomeric superfolder GFP (msfGFP) to the interior of the compartment by fusion of an N-terminal sequence of the propanediol utilization protein (PduP) of at least 24 amino acids. This study establishes the feasibility of constructing cell factories for small molecules in industrially important Bacillus and Geobacillus spp. by heterologous cargo-carrying BMC production and assembly. Additionally, the study provides experimental confirmation that BMCs are produced in thermophilic bacteria, which opens a path for future research on repurposing the native organelles to provide new functionality at elevated temperatures.
Collapse
Affiliation(s)
- Yana Wade
- Department of Biology & Biochemistry, University of Bath, Claverton Down, Bath, BA2 7AY, U.K
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, University of Newcastle, Newcastle-upon-Tyne, NE2 4AX, U.K
| | - Richard A. Daniel
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, University of Newcastle, Newcastle-upon-Tyne, NE2 4AX, U.K
| | - David J. Leak
- Department of Biology & Biochemistry, University of Bath, Claverton Down, Bath, BA2 7AY, U.K
| |
Collapse
|
16
|
Singleton C, Gilman J, Rollit J, Zhang K, Parker DA, Love J. A design of experiments approach for the rapid formulation of a chemically defined medium for metabolic profiling of industrially important microbes. PLoS One 2019; 14:e0218208. [PMID: 31188885 PMCID: PMC6561596 DOI: 10.1371/journal.pone.0218208] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Accepted: 05/28/2019] [Indexed: 12/30/2022] Open
Abstract
Geobacillus thermoglucosidans DSM2542 is an industrially important microbe, however the complex nutritional requirements of Geobacilli confound metabolic engineering efforts. Previous studies have utilised semi-defined media recipes that contain complex, undefined, biologically derived nutrients which have unknown ingredients that cannot be quantified during metabolic profiling. This study used design of experiments to investigate how individual nutrients and interactions between these nutrients contribute to growth. A mathematically derived defined medium has been formulated that has been shown to robustly support growth of G. thermoglucosidans in two different environmental conditions (96-well plate and shake flask) and with a variety of lignocellulose-based carbohydrates. This enabled the catabolism of industrially relevant carbohydrates to be investigated.
Collapse
Affiliation(s)
- Chloe Singleton
- The Exeter Microbial Biofuels Group, College of Life and Environmental Sciences, The University of Exeter, Exeter, Devon, United Kingdom
| | - James Gilman
- The Exeter Microbial Biofuels Group, College of Life and Environmental Sciences, The University of Exeter, Exeter, Devon, United Kingdom
| | - Jessica Rollit
- Department of Life Sciences, Imperial College London, London, United Kingdom
| | - Kun Zhang
- Shell Technology Centre, Houston, Texas, United States of America
| | - David A. Parker
- The Exeter Microbial Biofuels Group, College of Life and Environmental Sciences, The University of Exeter, Exeter, Devon, United Kingdom
- Shell Technology Centre, Houston, Texas, United States of America
| | - John Love
- The Exeter Microbial Biofuels Group, College of Life and Environmental Sciences, The University of Exeter, Exeter, Devon, United Kingdom
- * E-mail:
| |
Collapse
|
17
|
Gilman J, Singleton C, Tennant RK, James P, Howard TP, Lux T, Parker DA, Love J. Rapid, Heuristic Discovery and Design of Promoter Collections in Non-Model Microbes for Industrial Applications. ACS Synth Biol 2019; 8:1175-1186. [PMID: 30995831 DOI: 10.1021/acssynbio.9b00061] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Well-characterized promoter collections for synthetic biology applications are not always available in industrially relevant hosts. We developed a broadly applicable method for promoter identification in atypical microbial hosts that requires no a priori understanding of cis-regulatory element structure. This novel approach combines bioinformatic filtering with rapid empirical characterization to expand the promoter toolkit and uses machine learning to improve the understanding of the relationship between DNA sequence and function. Here, we apply the method in Geobacillus thermoglucosidasius, a thermophilic organism with high potential as a synthetic biology chassis for industrial applications. Bioinformatic screening of G. kaustophilus, G. stearothermophilus, G. thermodenitrificans, and G. thermoglucosidasius resulted in the identification of 636 100 bp putative promoters, encompassing the genome-wide design space and lacking known transcription factor binding sites. Eighty of these sequences were characterized in vivo, and activities covered a 2-log range of predictable expression levels. Seven sequences were shown to function consistently regardless of the downstream coding sequence. Partition modeling identified sequence positions upstream of the canonical -35 and -10 consensus motifs that were predicted to strongly influence regulatory activity in Geobacillus, and artificial neural network and partial least squares regression models were derived to assess if there were a simple, forward, quantitative method for in silico prediction of promoter function. However, the models were insufficiently general to predict pre hoc promoter activity in vivo, most probably as a result of the relatively small size of the training data set compared to the size of the modeled design space.
Collapse
Affiliation(s)
- James Gilman
- The BioEconomy Centre, Biosciences, College of Life and Environmental Sciences, Stocker Road, University of Exeter, Exeter EX4 4QD, U.K
| | - Chloe Singleton
- The BioEconomy Centre, Biosciences, College of Life and Environmental Sciences, Stocker Road, University of Exeter, Exeter EX4 4QD, U.K
| | - Richard K. Tennant
- The BioEconomy Centre, Biosciences, College of Life and Environmental Sciences, Stocker Road, University of Exeter, Exeter EX4 4QD, U.K
| | - Paul James
- The BioEconomy Centre, Biosciences, College of Life and Environmental Sciences, Stocker Road, University of Exeter, Exeter EX4 4QD, U.K
| | - Thomas P. Howard
- School of Natural and Environmental Sciences, Newcastle University, Devonshire Building, Newcastle-upon-Tyne NE1 7RU, U.K
| | - Thomas Lux
- Plant Genome and Systems Biology, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), Munich 85764, Germany
| | - David A. Parker
- Biodomain, Shell Technology Center Houston, 3333 Highway 6 South, Houston, Texas 77082-3101, United States
| | - John Love
- The BioEconomy Centre, Biosciences, College of Life and Environmental Sciences, Stocker Road, University of Exeter, Exeter EX4 4QD, U.K
| |
Collapse
|
18
|
Holland ATN, Danson MJ, Bolhuis A. Inhibition of extracellular proteases improves the production of a xylanase in Parageobacillus thermoglucosidasius. BMC Biotechnol 2019; 19:17. [PMID: 30894163 PMCID: PMC6425571 DOI: 10.1186/s12896-019-0511-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2018] [Accepted: 03/13/2019] [Indexed: 11/10/2022] Open
Abstract
Background Parageobacillus thermoglucosidasius is a thermophilic and ethanol-producing bacterium capable of utilising both hexose and pentose sugars for fermentation. The organism has been proposed to be a suitable organism for the production of bioethanol from lignocellulosic feedstocks. These feedstocks may be difficult to degrade, and a potential strategy to optimise this process is to engineer strains that secrete hydrolases that liberate increased amounts of sugars from those feedstocks. However, very little is known about protein transport in P. thermoglucosidasius and the limitations of that process, and as a first step we investigated whether there were bottlenecks in the secretion of a model protein. Results A secretory enzyme, xylanase (XynA1), was produced with and without its signal peptide. Cell cultures were fractionated into cytoplasm, membrane, cell wall, and extracellular milieu protein extracts, which were analysed using immunoblotting and enzyme activity assays. The main bottleneck identified was proteolytic degradation of XynA1 during or after its translocation. A combination of mass spectrometry and bioinformatics indicated the presence of several proteases that might be involved in this process. Conclusion The creation of protease-deficient strains may be beneficial towards the development of P. thermoglucosidasius as a platform organism for industrial processes. Electronic supplementary material The online version of this article (10.1186/s12896-019-0511-0) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Alexandria T N Holland
- Department of Pharmacy and Pharmacology, University of Bath, Claverton Down, Bath, BA2 7AY, UK.,Present address: Centre for Biomolecular Sciences, University of Nottingham, Nottingham, UK
| | - Michael J Danson
- Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath, BA2 7AY, UK
| | - Albert Bolhuis
- Department of Pharmacy and Pharmacology, University of Bath, Claverton Down, Bath, BA2 7AY, UK.
| |
Collapse
|
19
|
Daas MJA, Nijsse B, van de Weijer AHP, Groenendaal BWAJ, Janssen F, van der Oost J, van Kranenburg R. Engineering Geobacillus thermodenitrificans to introduce cellulolytic activity; expression of native and heterologous cellulase genes. BMC Biotechnol 2018; 18:42. [PMID: 29945583 PMCID: PMC6020330 DOI: 10.1186/s12896-018-0453-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Accepted: 06/14/2018] [Indexed: 11/28/2022] Open
Abstract
Background Consolidated bioprocessing (CBP) is a cost-effective approach for the conversion of lignocellulosic biomass to biofuels and biochemicals. The enzymatic conversion of cellulose to glucose requires the synergistic action of three types of enzymes: exoglucanases, endoglucanases and β-glucosidases. The thermophilic, hemicellulolytic Geobacillus thermodenitrificans T12 was shown to harbor desired features for CBP, although it lacks the desired endo and exoglucanases required for the conversion of cellulose. Here, we report the expression of both endoglucanase and exoglucanase encoding genes by G. thermodenitrificans T12, in an initial attempt to express cellulolytic enzymes that complement the enzymatic machinery of this strain. Results A metagenome screen was performed on 73 G. thermodenitrificans strains using HMM profiles of all known CAZy families that contain endo and/or exoglucanases. Two putative endoglucanases, GE39 and GE40, belonging to glucoside hydrolase family 5 (GH5) were isolated and expressed in both E. coli and G. thermodenitrificans T12. Structure modeling of GE39 revealed a folding similar to a GH5 exo-1,3-β-glucanase from S. cerevisiae. However, we determined GE39 to be a β-xylosidase having pronounced activity towards p-nitrophenyl-β-d-xylopyranoside. Structure modelling of GE40 revealed its protein architecture to be similar to a GH5 endoglucanase from B. halodurans, and its endoglucanase activity was confirmed by enzymatic activity against 2-hydroxyethylcellulose, carboxymethylcellulose and barley β-glucan. Additionally, we introduced expression constructs into T12 containing Geobacillus sp. 70PC53 endoglucanase gene celA and both endoglucanase genes (M1 and M2) from Geobacillus sp. WSUCF1. Finally, we introduced expression constructs into T12 containing the C. thermocellum exoglucanases celK and celS genes and the endoglucanase celC gene. Conclusions We identified a novel G. thermodenitrificans β-xylosidase (GE39) and a novel endoglucanase (GE40) using a metagenome screen based on multiple HMM profiles. We successfully expressed both genes in E. coli and functionally expressed the GE40 endoglucanase in G. thermodenitrificans T12. Additionally, the heterologous production of active CelK, a C. thermocellum derived exoglucanase, and CelA, a Geobacillus derived endoglucanase, was demonstrated with strain T12. The native hemicellulolytic activity and the heterologous cellulolytic activity described in this research provide a good basis for the further development of G. thermodenitrificans T12 as a host for consolidated bioprocessing. Electronic supplementary material The online version of this article (10.1186/s12896-018-0453-y) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Martinus J A Daas
- Laboratory of Microbiology, Wageningen University, Stippeneng 4, 6708, WE, Wageningen, The Netherlands
| | - Bart Nijsse
- Laboratory of Systems and Synthetic Biology, Wageningen University, Stippeneng 4, 6708, WE, Wageningen, The Netherlands
| | | | - Bart W A J Groenendaal
- Laboratory of Microbiology, Wageningen University, Stippeneng 4, 6708, WE, Wageningen, The Netherlands
| | - Fons Janssen
- Laboratory of Microbiology, Wageningen University, Stippeneng 4, 6708, WE, Wageningen, The Netherlands
| | - John van der Oost
- Laboratory of Microbiology, Wageningen University, Stippeneng 4, 6708, WE, Wageningen, The Netherlands
| | - Richard van Kranenburg
- Laboratory of Microbiology, Wageningen University, Stippeneng 4, 6708, WE, Wageningen, The Netherlands. .,Corbion, Arkelsedijk 46, 4206, AC, Gorinchem, The Netherlands.
| |
Collapse
|
20
|
Drejer EB, Hakvåg S, Irla M, Brautaset T. Genetic Tools and Techniques for Recombinant Expression in Thermophilic Bacillaceae. Microorganisms 2018; 6:microorganisms6020042. [PMID: 29748477 PMCID: PMC6027425 DOI: 10.3390/microorganisms6020042] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Revised: 05/02/2018] [Accepted: 05/03/2018] [Indexed: 01/17/2023] Open
Abstract
Although Escherichia coli and Bacillus subtilis are the most prominent bacterial hosts for recombinant protein production by far, additional species are being explored as alternatives for production of difficult-to-express proteins. In particular, for thermostable proteins, there is a need for hosts able to properly synthesize, fold, and excrete these in high yields, and thermophilic Bacillaceae represent one potentially interesting group of microorganisms for such purposes. A number of thermophilic Bacillaceae including B.methanolicus, B.coagulans, B.smithii, B.licheniformis, Geobacillus thermoglucosidasius, G. kaustophilus, and G. stearothermophilus are investigated concerning physiology, genomics, genetic tools, and technologies, altogether paving the way for their utilization as hosts for recombinant production of thermostable and other difficult-to-express proteins. Moreover, recent successful deployments of CRISPR/Cas9 in several of these species have accelerated the progress in their metabolic engineering, which should increase their attractiveness for future industrial-scale production of proteins. This review describes the biology of thermophilic Bacillaceae and in particular focuses on genetic tools and methods enabling use of these organisms as hosts for recombinant protein production.
Collapse
Affiliation(s)
- Eivind B Drejer
- Department of Biotechnology and Food Science, NTNU: Norwegian University of Science and Technology, 7491 Trondheim, Norway.
| | - Sigrid Hakvåg
- Department of Biotechnology and Food Science, NTNU: Norwegian University of Science and Technology, 7491 Trondheim, Norway.
| | - Marta Irla
- Department of Biotechnology and Food Science, NTNU: Norwegian University of Science and Technology, 7491 Trondheim, Norway.
| | - Trygve Brautaset
- Department of Biotechnology and Food Science, NTNU: Norwegian University of Science and Technology, 7491 Trondheim, Norway.
| |
Collapse
|
21
|
Modular assembling process of an in-silico protocell. Biosystems 2018; 165:8-21. [DOI: 10.1016/j.biosystems.2017.12.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Revised: 11/15/2017] [Accepted: 12/07/2017] [Indexed: 11/17/2022]
|
22
|
Frenzel E, Legebeke J, van Stralen A, van Kranenburg R, Kuipers OP. In vivo selection of sfGFP variants with improved and reliable functionality in industrially important thermophilic bacteria. BIOTECHNOLOGY FOR BIOFUELS 2018; 11:8. [PMID: 29371884 PMCID: PMC5771013 DOI: 10.1186/s13068-017-1008-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Accepted: 12/29/2017] [Indexed: 05/03/2023]
Abstract
BACKGROUND Fluorescent reporter proteins (FP) have become an indispensable tool for the optimization of microbial cell factories and in synthetic biology per se. The applicability of the currently available FPs is, however, constrained by species-dependent performance and misfolding at elevated temperatures. To obtain functional reporters for thermophilic, biotechnologically important bacteria such as Parageobacillus thermoglucosidasius, an in vivo screening approach based on a mutational library of superfolder GFP was applied. RESULTS Flow cytometry-based benchmarking of a set of GFPs, sfGFPs and species-specific codon-optimized variants revealed that none of the proteins was satisfyingly detectable in P. thermoglucosidasius at its optimal growth temperature of 60 °C. An undirected mutagenesis approach coupled to fluorescence-activated cell sorting allowed the isolation of sfGFP variants that were extremely well expressed in the chassis background at 60 °C. Notably, a few nucleotide substitutions, including silent mutations, significantly improved the functionality and brightness. The best mutant sfGFP(N39D/A179A) showed an 885-fold enhanced mean fluorescence intensity (MFI) at 60 °C and is the most reliable reporter protein with respect to cell-to-cell variation and signal intensity reported so far. The in vitro spectral and thermostability properties were unaltered as compared to the parental sfGFP protein, strongly indicating that the combination of the amino acid exchange and an altered translation or folding speed, or protection from degradation, contribute to the strongly improved in vivo performance. Furthermore, sfGFP(N39D/A179A) and the newly developed cyan and yellow derivatives were successfully used for labeling several industrially relevant thermophilic bacilli, thus proving their broad applicability. CONCLUSIONS This study illustrates the power of in vivo isolation of thermostable proteins to obtain reporters for highly efficient fluorescence labeling. Successful expression in a variety of thermophilic bacteria proved that the novel FPs are highly suitable for imaging and flow cytometry-based studies. This enables a reliable cell tracking and single-cell-based real-time monitoring of biological processes that are of industrial and biotechnological interest.
Collapse
Affiliation(s)
- Elrike Frenzel
- Department of Molecular Genetics, Groningen Biomolecular Sciences and Biotechnology Institute, Centre for Synthetic Biology, University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands
| | - Jelmer Legebeke
- Department of Molecular Genetics, Groningen Biomolecular Sciences and Biotechnology Institute, Centre for Synthetic Biology, University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands
| | - Atze van Stralen
- Department of Molecular Genetics, Groningen Biomolecular Sciences and Biotechnology Institute, Centre for Synthetic Biology, University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands
| | - Richard van Kranenburg
- Laboratory of Microbiology, Wageningen University, Stippeneng 4, 6708 WE Wageningen, The Netherlands
- Corbion, Arkselsedijk 46, 4206 AC Gorinchem, The Netherlands
| | - Oscar P. Kuipers
- Department of Molecular Genetics, Groningen Biomolecular Sciences and Biotechnology Institute, Centre for Synthetic Biology, University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands
| |
Collapse
|
23
|
Complete Genome Sequence of Geobacillus thermodenitrificans T12, A Potential Host for Biotechnological Applications. Curr Microbiol 2017; 75:49-56. [PMID: 28900693 PMCID: PMC5765199 DOI: 10.1007/s00284-017-1349-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Accepted: 08/28/2017] [Indexed: 01/12/2023]
Abstract
In attempt to obtain a thermophilic host for the conversion of lignocellulose derived substrates into lactic acid, Geobacillus thermodenitrificans T12 was isolated from a compost heap. It was selected from over 500 isolates as a genetically tractable hemicellulolytic lactic acid producer, requiring little nutrients. The strain is able to ferment glucose and xylose simultaneously and can produce lactic acid from xylan, making it a potential host for biotechnological applications. The genome of strain T12 consists of a 3.64 Mb chromosome and two plasmids of 59 and 56 kb. It has a total of 3.676 genes with an average genomic GC content of 48.7%. The T12 genome encodes a denitrification pathway, allowing for anaerobic respiration. The identity and localization of the responsible genes are similar to those of the denitrification pathways found in strain NG80-2. The hemicellulose utilization (HUS) locus was identified based on sequence homology against G. stearothermophilus T-6. It appeared that T12 has all the genes that are present in strain T-6 except for the arabinan degradation cluster. Instead, the HUS locus of strain T12 contains genes for both an inositol and a pectate degradation pathway. Strain T12 has complete pathways for the synthesis of purine and pyrimidine, all 20 amino acids and several vitamins except D-biotin. The host-defense systems present comprise a Type II and a Type III restriction-modification system, as well as a CRISPR-Cas Type II system. It is concluded that G. thermodenitrificans T12 is a potentially interesting candidate for industrial applications.
Collapse
|
24
|
Ahmad A, Hartman HB, Krishnakumar S, Fell DA, Poolman MG, Srivastava S. A Genome Scale Model of Geobacillus thermoglucosidasius (C56-YS93) reveals its biotechnological potential on rice straw hydrolysate. J Biotechnol 2017; 251:30-37. [DOI: 10.1016/j.jbiotec.2017.03.031] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Revised: 03/27/2017] [Accepted: 03/27/2017] [Indexed: 01/29/2023]
|
25
|
Bacon LF, Hamley-Bennett C, Danson MJ, Leak DJ. Development of an efficient technique for gene deletion and allelic exchange in Geobacillus spp. Microb Cell Fact 2017; 16:58. [PMID: 28381218 PMCID: PMC5382374 DOI: 10.1186/s12934-017-0670-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Accepted: 03/29/2017] [Indexed: 12/30/2022] Open
Abstract
Background Geobacillus thermoglucosidasius is a thermophilic, natural ethanol producer and a potential candidate for commercial bioethanol production. Previously, G. thermoglucosidasius has been genetically modified to create an industrially-relevant ethanol production strain. However, creating chromosomal integrations and deletions in Geobacillus spp. is laborious. Here we describe a new technique to create marker-less mutations in Geobacillus utilising a novel homologous recombination process. Results Our technique incorporates counter-selection using β-glucosidase and the synthetic substrate X-Glu, in combination with a two-step homologous recombination process where the first step is a selectable double-crossover event that deletes the target gene. We demonstrate how we have utilised this technique to delete two components of the proteinaceous shell of the Geobacillus propanediol-utilization microcompartment, and simultaneously introduce an oxygen-sensitive promoter in front of the remaining shell-component genes and confirm its functional incorporation. Conclusion The selectable deletion of the target gene in the first step of our process prevents re-creation of wild-type which can occur in most homologous recombination techniques, circumventing the need for PCR screening to identify mutants. Our new technique therefore offers a faster, more efficient method of creating mutants in Geobacillus.
Collapse
Affiliation(s)
- Leann F Bacon
- Department of Biology and Biochemistry, University of Bath, Bath, BA2 7AY, UK
| | | | - Michael J Danson
- Department of Biology and Biochemistry, University of Bath, Bath, BA2 7AY, UK
| | - David J Leak
- Department of Biology and Biochemistry, University of Bath, Bath, BA2 7AY, UK.
| |
Collapse
|
26
|
Reeve B, Martinez-Klimova E, de Jonghe J, Leak DJ, Ellis T. The Geobacillus Plasmid Set: A Modular Toolkit for Thermophile Engineering. ACS Synth Biol 2016; 5:1342-1347. [PMID: 27332993 DOI: 10.1021/acssynbio.5b00298] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Geobacillus thermoglucosidasius is a Gram-positive thermophile of industrial interest that exhibits rapid growth and can utilize a variety of plant-derived feedstocks. It is an attractive chassis organism for high temperature biotechnology and synthetic biology applications but is currently limited by a lack of available genetic tools. Here we describe a set of modular shuttle vectors, including a promoter library and reporter proteins. The compact plasmids are composed of interchangeable modules for molecular cloning in Escherichia coli and stable propagation in G. thermoglucosidasius and other Geobacillus species. Modules include two origins of replication, two selectable markers and three reporter proteins for characterization of gene expression. For fine-tuning heterologous expression from these plasmids, we include a characterized promoter library and test ribosome binding site design. Together, these gene expression tools and a standardized plasmid set can facilitate modularity and part exchange to make Geobacillus a thermophile chassis for synthetic biology.
Collapse
Affiliation(s)
- Benjamin Reeve
- Centre
for Synthetic Biology
and Innovation, Department of Bioengineering, Imperial College London, London SW7 2AZ, U.K
| | - Elena Martinez-Klimova
- Centre
for Synthetic Biology
and Innovation, Department of Bioengineering, Imperial College London, London SW7 2AZ, U.K
| | - Joachim de Jonghe
- Centre
for Synthetic Biology
and Innovation, Department of Bioengineering, Imperial College London, London SW7 2AZ, U.K
| | - David J. Leak
- Centre
for Synthetic Biology
and Innovation, Department of Bioengineering, Imperial College London, London SW7 2AZ, U.K
| | - Tom Ellis
- Centre
for Synthetic Biology
and Innovation, Department of Bioengineering, Imperial College London, London SW7 2AZ, U.K
| |
Collapse
|
27
|
Javed M, Baghaei-Yazdi N, Qin W, Amartey S. An improved agar medium for growth of Geobacillus thermoglucosidarius strains. J Microbiol Methods 2016; 132:116-118. [PMID: 27888139 DOI: 10.1016/j.mimet.2016.11.014] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2016] [Revised: 11/17/2016] [Accepted: 11/17/2016] [Indexed: 11/25/2022]
Abstract
Geobacillus species have potential applications in many biotechnological processes. They are fastidious in their vitamin and amino acid requirements. A new semi-defined agar medium (SDM) was developed which gave consistently high viable cell counts of various G. thermoglucosidasius strains (5×108-6×108cfu/ml) under aerobic conditions at 70°C.
Collapse
Affiliation(s)
- M Javed
- Division of Biology, Imperial College of Science Technology and Medicine, London SW7 AZ, UK; Biotech Consultants Ltd., 263 Frimley Green Road, Camberley, Surrey GU16 6LD, UK
| | - N Baghaei-Yazdi
- Division of Biology, Imperial College of Science Technology and Medicine, London SW7 AZ, UK; Biotech Consultants Ltd., 263 Frimley Green Road, Camberley, Surrey GU16 6LD, UK
| | - W Qin
- Department of Biology, Lakehead University, 955 Oliver Road, Thunder Bay, Ontario P7B 5E1, Canada
| | - S Amartey
- Division of Biology, Imperial College of Science Technology and Medicine, London SW7 AZ, UK.
| |
Collapse
|
28
|
Study on dyeing wastewater treatment at high temperature by MBBR and the thermotolerant mechanism based on its microbial analysis. Process Biochem 2015. [DOI: 10.1016/j.procbio.2015.08.007] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
29
|
Genome sequence of Geobacillus thermoglucosidasius DSM2542, a platform hosts for biotechnological applications with industrial potential. J Biotechnol 2015; 216:98-9. [PMID: 26467717 DOI: 10.1016/j.jbiotec.2015.10.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Accepted: 10/05/2015] [Indexed: 11/23/2022]
Abstract
Thermophilic Geobacillus thermoglucosidasius could ferment a wide range of substrates with low nutrient requirements for growth. Here, the first released the complete genome sequence of G. thermoglucosidasius DSM2542 may facilitate the design of rational strategies for further strain improvements and provide information for exploring industrially interesting enzymes with thermotolerant properties.
Collapse
|
30
|
Abstract
The genus Geobacillus comprises a group of Gram-positive thermophilic bacteria, including obligate aerobes, denitrifiers, and facultative anaerobes that can grow over a range of 45-75°C. Originally classified as group five Bacillus spp., strains of Bacillus stearothermophilus came to prominence as contaminants of canned food and soon became the organism of choice for comparative studies of metabolism and enzymology between mesophiles and thermophiles. More recently, their catabolic versatility, particularly in the degradation of hemicellulose and starch, and rapid growth rates have raised their profile as organisms with potential for second-generation (lignocellulosic) biorefineries for biofuel or chemical production. The continued development of genetic tools to facilitate both fundamental investigation and metabolic engineering is now helping to realize this potential, for both metabolite production and optimized catabolism. In addition, this catabolic versatility provides a range of useful thermostable enzymes for industrial application. A number of genome-sequencing projects have been completed or are underway allowing comparative studies. These reveal a significant amount of genome rearrangement within the genus, the presence of large genomic islands encompassing all the hemicellulose utilization genes and a genomic island incorporating a set of long chain alkane monooxygenase genes. With G+C contents of 45-55%, thermostability appears to derive in part from the ability to synthesize protamine and spermine, which can condense DNA and raise its Tm.
Collapse
|
31
|
Kananavičiūtė R, Čitavičius D. Genetic engineering of Geobacillus spp. J Microbiol Methods 2015; 111:31-9. [DOI: 10.1016/j.mimet.2015.02.002] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2014] [Revised: 02/02/2015] [Accepted: 02/02/2015] [Indexed: 11/15/2022]
|
32
|
Kelwick R, MacDonald JT, Webb AJ, Freemont P. Developments in the tools and methodologies of synthetic biology. Front Bioeng Biotechnol 2014; 2:60. [PMID: 25505788 PMCID: PMC4244866 DOI: 10.3389/fbioe.2014.00060] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2014] [Accepted: 11/12/2014] [Indexed: 11/27/2022] Open
Abstract
Synthetic biology is principally concerned with the rational design and engineering of biologically based parts, devices, or systems. However, biological systems are generally complex and unpredictable, and are therefore, intrinsically difficult to engineer. In order to address these fundamental challenges, synthetic biology is aiming to unify a “body of knowledge” from several foundational scientific fields, within the context of a set of engineering principles. This shift in perspective is enabling synthetic biologists to address complexity, such that robust biological systems can be designed, assembled, and tested as part of a biological design cycle. The design cycle takes a forward-design approach in which a biological system is specified, modeled, analyzed, assembled, and its functionality tested. At each stage of the design cycle, an expanding repertoire of tools is being developed. In this review, we highlight several of these tools in terms of their applications and benefits to the synthetic biology community.
Collapse
Affiliation(s)
- Richard Kelwick
- Centre for Synthetic Biology and Innovation, Imperial College London , London , UK ; Department of Medicine, Imperial College London , London , UK
| | - James T MacDonald
- Centre for Synthetic Biology and Innovation, Imperial College London , London , UK ; Department of Medicine, Imperial College London , London , UK
| | - Alexander J Webb
- Centre for Synthetic Biology and Innovation, Imperial College London , London , UK ; Department of Medicine, Imperial College London , London , UK
| | - Paul Freemont
- Centre for Synthetic Biology and Innovation, Imperial College London , London , UK ; Department of Medicine, Imperial College London , London , UK
| |
Collapse
|
33
|
Affiliation(s)
- David J Studholme
- Biosciences, University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter, EX4 4QD, UK
| |
Collapse
|
34
|
Lin PP, Rabe KS, Takasumi JL, Kadisch M, Arnold FH, Liao JC. Erratum to “Isobutanol production at elevated temperatures in thermophilic Geobacillus thermoglucosidasius” [Metab. Eng. 24C (2014) 1–8]. Metab Eng 2014. [DOI: 10.1016/j.ymben.2014.06.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
|
35
|
Kananavičiūtė R, Butaitė E, Čitavičius D. Characterization of two novel plasmids from Geobacillus sp. 610 and 1121 strains. Plasmid 2014; 71:23-31. [DOI: 10.1016/j.plasmid.2013.10.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2013] [Revised: 10/01/2013] [Accepted: 10/17/2013] [Indexed: 11/28/2022]
|
36
|
Roberts MAJ, Cranenburgh RM, Stevens MP, Oyston PCF. Synthetic biology: biology by design. MICROBIOLOGY-SGM 2013; 159:1219-1220. [PMID: 23744901 PMCID: PMC3749723 DOI: 10.1099/mic.0.069724-0] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- M A J Roberts
- Barts and The London School of Medicine and Dentistry, Queen Mary University of London, Garrod Building, Turner St., Whitechapel, London E1 2AD, UK
| | - R M Cranenburgh
- Prokarium Ltd, Stephenson Building, Keele Science Park, Keele, Staffordshire ST5 5SP, UK
| | - M P Stevens
- The Roslin Institute & Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush, Midlothian EH25 9RG, UK
| | - P C F Oyston
- Biomedical Sciences, DSTL Porton Down, Salisbury, Wiltshire SP4 0JQ, UK
| |
Collapse
|