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Sajjadi S, Wu SJ, Rabbani Y, Zubkovs V, Ahmadzadeh H, K. Goharshadi E, Boghossian AA. Micropreparative Gel Electrophoresis for Purification of Nanoscale Bioconjugates. Bioconjug Chem 2024; 35:154-163. [PMID: 38320084 PMCID: PMC10885001 DOI: 10.1021/acs.bioconjchem.3c00388] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Revised: 01/03/2024] [Accepted: 01/03/2024] [Indexed: 02/08/2024]
Abstract
Conventional techniques for purifying macromolecular conjugates often require complex and costly installments that are inaccessible to most laboratories. In this work, we develop a one-step micropreparative method based on a trilayered polyacrylamide gel electrophoresis (MP-PAGE) setup to purify biological samples, synthetic nanoparticles, as well as biohybrid complexes. We apply this method to recover DNA from a ladder mixture with yields of up to 90%, compared to the 58% yield obtained using the conventional crush-and-soak method. MP-PAGE was also able to isolate enhanced yellow fluorescence protein (EYFP) from crude cell extract with 90% purity, which is comparable to purities achieved through a more complex two-step purification procedure involving size exclusion and immobilized metal-ion affinity chromatography. This technique was further extended to demonstrate size-dependent separation of a commercial mixture of graphene quantum dots (GQDs) into three different fractions with distinct optical properties. Finally, MP-PAGE was used to isolate DNA-EYFP and DNA-GQD bioconjugates from their reaction mixture of DNA and EYFP and GQD precursors, samples that otherwise could not be effectively purified by conventional chromatography. MP-PAGE thus offers a rapid and versatile means of purifying biological and synthetic nanomaterials without the need for specialized equipment.
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Affiliation(s)
- Sayyed
Hashem Sajjadi
- Ecole
Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland
- Chemistry
Department, Faculty of Science, Ferdowsi
University of Mashhad, Mashhad 9177948974, Iran
| | - Shang-Jung Wu
- Ecole
Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland
| | - Yahya Rabbani
- Ecole
Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland
| | - Vitalijs Zubkovs
- Ecole
Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland
| | - Hossein Ahmadzadeh
- Chemistry
Department, Faculty of Science, Ferdowsi
University of Mashhad, Mashhad 9177948974, Iran
| | - Elaheh K. Goharshadi
- Chemistry
Department, Faculty of Science, Ferdowsi
University of Mashhad, Mashhad 9177948974, Iran
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Li M, Sun X, Chen H, Li N, Feng Y, Xiao L, Guo Y. Stable expression of mucin glycoproteins GP40 and GP15 of Cryptosporidium parvum in Toxoplasma gondii. Parasit Vectors 2024; 17:65. [PMID: 38360646 PMCID: PMC10870685 DOI: 10.1186/s13071-024-06159-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Accepted: 01/24/2024] [Indexed: 02/17/2024] Open
Abstract
BACKGROUND Cryptosporidium spp. are common protozoa causing diarrhea in humans and animals. There are currently only one FDA-approved drug and no vaccines for cryptosporidiosis, largely due to the limited knowledge of the molecular mechanisms involved in the invasion of the pathogens. Previous studies have shown that GP60, which is cleaved into GP40 and GP15 after expression, is an immunodominant mucin protein involved in the invasion of Cryptosporidium. The protein is highly O-glycosylated, and recombinant proteins expressed in prokaryotic systems are non-functional. Therefore, few studies have investigated the function of GP40 and GP15. METHODS To obtain recombinant GP40 with correct post-translational modifications, we used CRISPR/Cas9 technology to insert GP40 and GP15 into the UPRT locus of Toxoplasma gondii, allowing heterologous expression of Cryptosporidium proteins. In addition, the Twin-Strep tag was inserted after GP40 for efficient purification of GP40. RESULTS Western blotting and immunofluorescent microscopic analyses both indicated that GP40 and GP15 were stably expressed in T. gondii mutants. GP40 localized not only in the cytoplasm of tachyzoites but also in the parasitophorous vacuoles, while GP15 without the GPI anchor was expressed only in the cytoplasm. In addition, a large amount of recTgGP40 was purified using Strep-TactinXT supported by a visible band of ~ 50 kDa in SDS-PAGE. CONCLUSIONS The establishment of a robust and efficient heterologous expression system of GP40 in T. gondii represents a novel approach and concept for investigating Cryptosporidium mucins, overcoming the limitations of previous studies that relied on unstable transient transfection, which involved complex steps and high costs.
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Affiliation(s)
- Muxiao Li
- State Key Laboratory for Animal Disease Control and Prevention, South China Agricultural University, Guangzhou, 510642, China
| | - Xiaohua Sun
- State Key Laboratory for Animal Disease Control and Prevention, South China Agricultural University, Guangzhou, 510642, China
| | - Haoyu Chen
- State Key Laboratory for Animal Disease Control and Prevention, South China Agricultural University, Guangzhou, 510642, China
| | - Na Li
- State Key Laboratory for Animal Disease Control and Prevention, South China Agricultural University, Guangzhou, 510642, China
| | - Yaoyu Feng
- State Key Laboratory for Animal Disease Control and Prevention, South China Agricultural University, Guangzhou, 510642, China
| | - Lihua Xiao
- State Key Laboratory for Animal Disease Control and Prevention, South China Agricultural University, Guangzhou, 510642, China
| | - Yaqiong Guo
- State Key Laboratory for Animal Disease Control and Prevention, South China Agricultural University, Guangzhou, 510642, China.
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3
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Mutyala S, Li S, Khandelwal H, Kong DS, Kim JR. Citrate Synthase Overexpression of Pseudomonas putida Increases Succinate Production from Acetate in Microaerobic Cultivation. ACS OMEGA 2023; 8:26231-26242. [PMID: 37521642 PMCID: PMC10373214 DOI: 10.1021/acsomega.3c02520] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Accepted: 06/28/2023] [Indexed: 08/01/2023]
Abstract
Acetate is an end-product of anaerobic biodegradation and one of the major metabolites of microbial fermentation and lingo-cellulosic hydrolysate. Recently, acetate has been highlighted as a feedstock to produce value-added chemicals. This study examined acetate conversion to succinate by citrate synthase (gltA)-overexpressed Pseudomonas putida under microaerobic conditions. The acetate metabolism is initiated with the gltA enzyme, which converts acetyl-CoA to citrate. gltA-overexpressing P. putida (gltA-KT) showed an ∼50% improvement in succinate production compared to the wild type. Under the optimal pH of 7.5, the accumulation of succinate (4.73 ± 0.6 mM in 36 h) was ∼400% higher than that of the wild type. Overall, gltA overexpression alone resulted in 9.5% of the maximum theoretical yield in a minimal medium with acetate as the sole carbon source. This result shows that citrate synthase is important in acetate conversion to succinate by P. putida under microaerobic conditions.
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Elston KM, Phillips LE, Leonard SP, Young E, Holley JAC, Ahsanullah T, McReynolds B, Moran NA, Barrick JE. The Pathfinder plasmid toolkit for genetically engineering newly isolated bacteria enables the study of Drosophila-colonizing Orbaceae. ISME COMMUNICATIONS 2023; 3:49. [PMID: 37225918 PMCID: PMC10209150 DOI: 10.1038/s43705-023-00255-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2023] [Revised: 04/18/2023] [Accepted: 05/11/2023] [Indexed: 05/26/2023]
Abstract
Toolkits of plasmids and genetic parts streamline the process of assembling DNA constructs and engineering microbes. Many of these kits were designed with specific industrial or laboratory microbes in mind. For researchers interested in non-model microbial systems, it is often unclear which tools and techniques will function in newly isolated strains. To address this challenge, we designed the Pathfinder toolkit for quickly determining the compatibility of a bacterium with different plasmid components. Pathfinder plasmids combine three different broad-host-range origins of replication with multiple antibiotic resistance cassettes and reporters, so that sets of parts can be rapidly screened through multiplex conjugation. We first tested these plasmids in Escherichia coli, a strain of Sodalis praecaptivus that colonizes insects, and a Rosenbergiella isolate from leafhoppers. Then, we used the Pathfinder plasmids to engineer previously unstudied bacteria from the family Orbaceae that were isolated from several fly species. Engineered Orbaceae strains were able to colonize Drosophila melanogaster and could be visualized in fly guts. Orbaceae are common and abundant in the guts of wild-caught flies but have not been included in laboratory studies of how the Drosophila microbiome affects fly health. Thus, this work provides foundational genetic tools for studying microbial ecology and host-associated microbes, including bacteria that are a key constituent of the gut microbiome of a model insect species.
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Affiliation(s)
- Katherine M Elston
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX, 78712, USA
| | - Laila E Phillips
- Department of Integrative Biology, The University of Texas at Austin, Austin, TX, 78712, USA
| | - Sean P Leonard
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX, 78712, USA
- Department of Integrative Biology, The University of Texas at Austin, Austin, TX, 78712, USA
| | - Eleanor Young
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX, 78712, USA
| | - Jo-Anne C Holley
- Department of Integrative Biology, The University of Texas at Austin, Austin, TX, 78712, USA
- Freshman Research Initiative, The University of Texas at Austin, Austin, TX, 78712, USA
| | - Tasneem Ahsanullah
- Freshman Research Initiative, The University of Texas at Austin, Austin, TX, 78712, USA
| | - Braydin McReynolds
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX, 78712, USA
| | - Nancy A Moran
- Department of Integrative Biology, The University of Texas at Austin, Austin, TX, 78712, USA
| | - Jeffrey E Barrick
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX, 78712, USA.
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5
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Elston KM, Phillips LE, Leonard SP, Young E, Holley JAC, Ahsanullah T, McReynolds B, Moran NA, Barrick JE. The Pathfinder plasmid toolkit for genetically engineering newly isolated bacteria enables the study of Drosophila -colonizing Orbaceae. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.02.15.528778. [PMID: 36824770 PMCID: PMC9949093 DOI: 10.1101/2023.02.15.528778] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
Toolkits of plasmids and genetic parts streamline the process of assembling DNA constructs and engineering microbes. Many of these kits were designed with specific industrial or laboratory microbes in mind. For researchers interested in non-model microbial systems, it is often unclear which tools and techniques will function in newly isolated strains. To address this challenge, we designed the Pathfinder toolkit for quickly determining the compatibility of a bacterium with different plasmid components. Pathfinder plasmids combine three different broad-host-range origins of replication with multiple antibiotic resistance cassettes and reporters, so that sets of parts can be rapidly screened through multiplex conjugation. We first tested these plasmids in Escherichia coli , a strain of Sodalis praecaptivus that colonizes insects, and a Rosenbergiella isolate from leafhoppers. Then, we used the Pathfinder plasmids to engineer previously unstudied bacteria from the family Orbaceae that were isolated from several fly species. Engineered Orbaceae strains were able to colonize Drosophila melanogaster and could be visualized in fly guts. Orbaceae are common and abundant in the guts of wild-caught flies but have not been included in laboratory studies of how the Drosophila microbiome affects fly health. Thus, this work provides foundational genetic tools for studying new host-associated microbes, including bacteria that are a key constituent of the gut microbiome of a model insect species. IMPORTANCE To fully understand how microbes have evolved to interact with their environments, one must be able to modify their genomes. However, it can be difficult and laborious to discover which genetic tools and approaches work for a new isolate. Bacteria from the recently described Orbaceae family are common in the microbiomes of insects. We developed the Pathfinder plasmid toolkit for testing the compatibility of different genetic parts with newly cultured bacteria. We demonstrate its utility by engineering Orbaceae strains isolated from flies to express fluorescent proteins and characterizing how they colonize the Drosophila melanogaster gut. Orbaceae are widespread in Drosophila in the wild but have not been included in laboratory studies examining how the gut microbiome affects fly nutrition, health, and longevity. Our work establishes a path for genetic studies aimed at understanding and altering interactions between these and other newly isolated bacteria and their hosts.
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Affiliation(s)
- Katherine M. Elston
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX 78712, USA
| | - Laila E. Phillips
- Department of Integrative Biology, The University of Texas at Austin, Austin, TX 78712, USA
| | - Sean P. Leonard
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX 78712, USA
- Department of Integrative Biology, The University of Texas at Austin, Austin, TX 78712, USA
| | - Eleanor Young
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX 78712, USA
| | - Jo-anne C. Holley
- Department of Integrative Biology, The University of Texas at Austin, Austin, TX 78712, USA
- Freshman Research Initiative, The University of Texas at Austin, Austin, TX 78712, USA
| | - Tasneem Ahsanullah
- Freshman Research Initiative, The University of Texas at Austin, Austin, TX 78712, USA
| | - Braydin McReynolds
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX 78712, USA
| | - Nancy A. Moran
- Department of Integrative Biology, The University of Texas at Austin, Austin, TX 78712, USA
| | - Jeffrey E. Barrick
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX 78712, USA
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6
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Zou L, Zhang C, Li Y, Yang X, Wang Y, Yan Y, Yang R, Huang M, Haq F, Yang C, Chen G. An improved, versatile and efficient modular plasmid assembly system for expression analyses of genes in Xanthomonas oryzae. MOLECULAR PLANT PATHOLOGY 2021; 22:480-492. [PMID: 33486879 PMCID: PMC7938625 DOI: 10.1111/mpp.13033] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/15/2020] [Revised: 12/02/2020] [Accepted: 12/10/2020] [Indexed: 06/12/2023]
Abstract
Xanthomonas oryzae pathovars oryzae (Xoo) and oryzicola (Xoc) infect rice, causing bacterial blight and bacterial leaf streak, respectively, which are two economically important bacterial diseases in paddy fields. The interactions of Xoo and Xoc with rice can be used as models for studying fundamental aspects of bacterial pathogenesis and host tissue specificity. However, an improved vector system for gene expression analysis is desired for Xoo and Xoc because some broad host range vectors that can replicate stably in X. oryzae pathovars are low-copy number plasmids. To overcome this limitation, we developed a modular plasmid assembly system to transfer the functional DNA modules from the entry vectors into the pHM1-derived backbone vectors on a high-copy number basis. We demonstrated the feasibility of our vector system for protein detection, and quantification of virulence gene expression under laboratory conditions and in association with host rice and nonhost tobacco cells. This system also allows execution of a mutant complementation equivalent to the single-copy chromosomal integration system and tracing of pathogens in rice leaf. Based on this assembly system, we constructed a series of protein expression and promoter-probe vectors suitable for classical double restriction enzyme cloning. These vector systems enable cloning of all genes or promoters of interest from Xoo and Xoc strains. Our modular assembly system represents a versatile and highly efficient toolkit for gene expression analysis that will accelerate studies on interactions of X. oryzae with rice.
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Affiliation(s)
- Lifang Zou
- School of Agriculture and BiologyShanghai Jiao Tong UniversityShanghaiChina
- Key Laboratory of Urban Agriculture by Ministry of Agriculture of ChinaShanghai Jiao Tong UniversityShanghaiChina
- State Key Laboratory of Microbial MetabolismSchool of Life Sciences & BiotechnologyShanghai Jiao Tong UniversityShanghaiChina
| | - Cuiping Zhang
- School of Agriculture and BiologyShanghai Jiao Tong UniversityShanghaiChina
| | - Yilang Li
- School of Agriculture and BiologyShanghai Jiao Tong UniversityShanghaiChina
| | - Xiaofei Yang
- School of Agriculture and BiologyShanghai Jiao Tong UniversityShanghaiChina
| | - Yanyan Wang
- School of Agriculture and BiologyShanghai Jiao Tong UniversityShanghaiChina
| | - Yichao Yan
- School of Agriculture and BiologyShanghai Jiao Tong UniversityShanghaiChina
| | - Ruihuan Yang
- School of Agriculture and BiologyShanghai Jiao Tong UniversityShanghaiChina
| | - Mengsang Huang
- School of Agriculture and BiologyShanghai Jiao Tong UniversityShanghaiChina
| | - Fazal Haq
- School of Agriculture and BiologyShanghai Jiao Tong UniversityShanghaiChina
| | - Ching‐Hong Yang
- Department of Biological SciencesUniversity of WisconsinMilwaukeeWisconsinUSA
| | - Gongyou Chen
- School of Agriculture and BiologyShanghai Jiao Tong UniversityShanghaiChina
- Key Laboratory of Urban Agriculture by Ministry of Agriculture of ChinaShanghai Jiao Tong UniversityShanghaiChina
- State Key Laboratory of Microbial MetabolismSchool of Life Sciences & BiotechnologyShanghai Jiao Tong UniversityShanghaiChina
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7
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Cambré A, Aertsen A. Bacterial Vivisection: How Fluorescence-Based Imaging Techniques Shed a Light on the Inner Workings of Bacteria. Microbiol Mol Biol Rev 2020; 84:e00008-20. [PMID: 33115939 PMCID: PMC7599038 DOI: 10.1128/mmbr.00008-20] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The rise in fluorescence-based imaging techniques over the past 3 decades has improved the ability of researchers to scrutinize live cell biology at increased spatial and temporal resolution. In microbiology, these real-time vivisections structurally changed the view on the bacterial cell away from the "watery bag of enzymes" paradigm toward the perspective that these organisms are as complex as their eukaryotic counterparts. Capitalizing on the enormous potential of (time-lapse) fluorescence microscopy and the ever-extending pallet of corresponding probes, initial breakthroughs were made in unraveling the localization of proteins and monitoring real-time gene expression. However, later it became clear that the potential of this technique extends much further, paving the way for a focus-shift from observing single events within bacterial cells or populations to obtaining a more global picture at the intra- and intercellular level. In this review, we outline the current state of the art in fluorescence-based vivisection of bacteria and provide an overview of important case studies to exemplify how to use or combine different strategies to gain detailed information on the cell's physiology. The manuscript therefore consists of two separate (but interconnected) parts that can be read and consulted individually. The first part focuses on the fluorescent probe pallet and provides a perspective on modern methodologies for microscopy using these tools. The second section of the review takes the reader on a tour through the bacterial cell from cytoplasm to outer shell, describing strategies and methods to highlight architectural features and overall dynamics within cells.
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Affiliation(s)
- Alexander Cambré
- KU Leuven, Department of Microbial and Molecular Systems, Faculty of Bioscience Engineering, Leuven, Belgium
| | - Abram Aertsen
- KU Leuven, Department of Microbial and Molecular Systems, Faculty of Bioscience Engineering, Leuven, Belgium
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8
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Stiller LM, Galinski EA, Witt EMHJ. Engineering the Salt-Inducible Ectoine Promoter Region of Halomonas elongata for Protein Expression in a Unique Stabilizing Environment. Genes (Basel) 2018; 9:genes9040184. [PMID: 29597294 PMCID: PMC5924526 DOI: 10.3390/genes9040184] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Revised: 03/19/2018] [Accepted: 03/21/2018] [Indexed: 01/11/2023] Open
Abstract
It has been firmly established that organic osmolytes (compatible solutes) of halophilic Bacteria and Archaea have positive effects on conformation and activity of proteins, and may therefore improve their functional production. In particular, the amino acid derivative ectoine is known for its conformational stabilization, aggregation suppression, and radical protection properties. The natural producer and industrial production strain Halomonas elongata accumulates ectoine in the cytoplasm, and as a result offers a unique stabilizing environment for recombinant proteins. For the construction of broad hoast range vector systems with fluorescent reporter proteins, we chose the salt-inducible promoter region of the ectoine gene cluster (promA). A closer inspection of the genetic background revealed that its combination of sigma 38 (σ38) and sigma 70 (σ70) promoters was followed by a weak ribosomal binding site (RBS). This inspired a systematic approach for the construction of a promA-based vector series with a synthetic RBS region using the RBS Calculator v2.0, which resulted in a greatly improved salt-dependent expression-even in a deletion construct lacking the σ38 promoter. To expand the application range of this expression system, we looked further into the possible export of recombinant proteins into the periplasm. Both sec and tat leader sequences from H. elongata proved to be suitable for directed periplasmic transport into an extreme environment of freely selectable ionic strength.
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Affiliation(s)
- Lisa M Stiller
- Institute of Microbiology and Biotechnology, Rheinische Friedrich-Wilhelms University Bonn, 53115 Bonn, Germany.
| | - Erwin A Galinski
- Institute of Microbiology and Biotechnology, Rheinische Friedrich-Wilhelms University Bonn, 53115 Bonn, Germany.
| | - Elisabeth M H J Witt
- Institute of Microbiology and Biotechnology, Rheinische Friedrich-Wilhelms University Bonn, 53115 Bonn, Germany.
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9
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Webster GR, Teh AYH, Ma JKC. Synthetic gene design-The rationale for codon optimization and implications for molecular pharming in plants. Biotechnol Bioeng 2016; 114:492-502. [PMID: 27618314 DOI: 10.1002/bit.26183] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2015] [Revised: 08/10/2016] [Accepted: 09/05/2016] [Indexed: 12/14/2022]
Abstract
Degeneracy in the genetic code allows multiple codon sequences to encode the same protein. Codon usage bias in genes is the term given to the preferred use of particular synonymous codons. Synonymous codon substitutions had been regarded as "silent" as the primary structure of the protein was not affected; however, it is now accepted that synonymous substitutions can have a significant effect on heterologous protein expression. Codon optimization, the process of altering codons within the gene sequence to improve recombinant protein expression, has become widely practised. Multiple inter-linked factors affecting protein expression need to be taken into consideration when optimizing a gene sequence. Over the years, various computer programmes have been developed to aid in the gene sequence optimization process. However, as the rulebook for altering codon usage to affect protein expression is still not completely understood, it is difficult to predict which strategy, if any, will design the "optimal" gene sequence. In this review, codon usage bias and factors affecting codon selection will be discussed and the evidence for codon optimization impact will be reviewed for recombinant protein expression using plants as a case study. These developments will be relevant to all recombinant expression systems; however, molecular pharming in plants is an area which has consistently encountered difficulties with low levels of recombinant protein expression, and should benefit from an evidence based rational approach to synthetic gene design. Biotechnol. Bioeng. 2017;114: 492-502. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Gina R Webster
- Molecular Immunology Unit, Institute for Infection and Immunity, St. George's University of London, SW17 0RE, London, UK
| | - Audrey Y-H Teh
- Molecular Immunology Unit, Institute for Infection and Immunity, St. George's University of London, SW17 0RE, London, UK
| | - Julian K-C Ma
- Molecular Immunology Unit, Institute for Infection and Immunity, St. George's University of London, SW17 0RE, London, UK
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10
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Boute N, Lowe P, Berger S, Malissard M, Robert A, Tesar M. NanoLuc Luciferase - A Multifunctional Tool for High Throughput Antibody Screening. Front Pharmacol 2016; 7:27. [PMID: 26924984 PMCID: PMC4758271 DOI: 10.3389/fphar.2016.00027] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2015] [Accepted: 01/29/2016] [Indexed: 01/22/2023] Open
Abstract
Based on the recent development of NanoLuc luciferase (Nluc), a small (19 kDa), highly stable, ATP independent, bioluminescent protein, an extremely robust and ultra high sensitivity screening system has been developed whereby primary hits of therapeutic antibodies and antibody fragments could be characterized and quantified without purification. This system is very versatile allowing cellular and solid phase ELISA but also homogeneous BRET based screening assays, relative affinity determinations with competition ELISA and direct Western blotting. The new Nluc protein fusion represents a “swiss army knife solution” for today and future high throughput antibody drug screenings.
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Affiliation(s)
- Nicolas Boute
- Molecular and Cellular Biology Unit, Institut de Recherche Pierre Fabre, Centre d'Immunologie Pierre Fabre Saint-Julien-en-Genevois, France
| | - Peter Lowe
- Molecular and Cellular Biology Unit, Institut de Recherche Pierre Fabre, Centre d'Immunologie Pierre Fabre Saint-Julien-en-Genevois, France
| | - Sven Berger
- Molecular and Cellular Biology Unit, Institut de Recherche Pierre Fabre, Centre d'Immunologie Pierre Fabre Saint-Julien-en-Genevois, France
| | - Martine Malissard
- Biochemistry Department, Institut de Recherche Pierre Fabre, Centre d'Immunologie Pierre Fabre Saint-Julien-en Genevois, France
| | - Alain Robert
- Molecular and Cellular Biology Unit, Institut de Recherche Pierre Fabre, Centre d'Immunologie Pierre Fabre Saint-Julien-en-Genevois, France
| | - Michael Tesar
- Molecular and Cellular Biology Unit, Institut de Recherche Pierre Fabre, Centre d'Immunologie Pierre Fabre Saint-Julien-en-Genevois, France
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Super-Resolution Imaging Conditions for enhanced Yellow Fluorescent Protein (eYFP) Demonstrated on DNA Origami Nanorulers. Sci Rep 2015; 5:14075. [PMID: 26373229 PMCID: PMC4571581 DOI: 10.1038/srep14075] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2015] [Accepted: 08/07/2015] [Indexed: 01/31/2023] Open
Abstract
Photostability is one of the crucial properties of a fluorophore which strongly influences the quality of single molecule-based super-resolution imaging. Enhanced yellow fluorescent protein (eYFP) is one of the most widely used versions of fluorescent proteins in modern cell biology exhibiting fast intrinsic blinking and reversible photoactivation by UV light. Here, we developed an assay for studying photostabilization of single eYFP molecules with respect to fast blinking and demonstrated a 6-fold enhanced photostability of single eYFP molecules with a beneficial influence on the blinking kinetics under oxygen removal and addition of aliphatic thiols (dSTORM-buffer). Conjugation to single stranded DNA and immobilization via DNA hybridization on a DNA origami 12 helix bundle in aqueous solution allowed photophyiscal studies of eYFP at the single-molecule level and at close to physiological conditions. The benefit of improved photophysical properties for localization-based super-resolution microscopy is demonstrated and quantitatively characterized by imaging 12 helix bundle DNA origami nanorulers with binding sites at designed distances of 160 and 100 nm and by imaging microtubules in fixed mammalian Vero cells.
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12
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Hoffmann J, Altenbuchner J. Functional Characterization of the Mannitol Promoter of Pseudomonas fluorescens DSM 50106 and Its Application for a Mannitol-Inducible Expression System for Pseudomonas putida KT2440. PLoS One 2015; 10:e0133248. [PMID: 26207762 PMCID: PMC4514859 DOI: 10.1371/journal.pone.0133248] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2015] [Accepted: 06/24/2015] [Indexed: 01/29/2023] Open
Abstract
A new pBBR1MCS-2-derived vector containing the Pseudomonas fluorescens DSM10506 mannitol promoter PmtlE and mtlR encoding its AraC/XylS type transcriptional activator was constructed and optimized for low basal expression. Mannitol, arabitol, and glucitol-inducible gene expression was demonstrated with Pseudomonas putida and eGFP as reporter gene. The new vector was applied for functional characterization of PmtlE. Identification of the DNA binding site of MtlR was achieved by in vivo eGFP measurement with PmtlE wild type and mutants thereof. Moreover, purified MtlR was applied for detailed in vitro investigations using electrophoretic mobility shift assays and DNaseI footprinting experiments. The obtained data suggest that MtlR binds to PmtlE as a dimer. The proposed DNA binding site of MtlR is AGTGC-N5-AGTAT-N7-AGTGC-N5-AGGAT. The transcription activation mechanism includes two binding sites with different binding affinities, a strong upstream binding site and a weaker downstream binding site. The presence of the weak downstream binding site was shown to be necessary to sustain mannitol-inducibility of PmtlE. Two possible functions of mannitol are discussed; the effector might stabilize binding of the second monomer to the downstream half site or promote transcription activation by inducing a conformational change of the regulator that influences the contact to the RNA polymerase.
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Affiliation(s)
- Jana Hoffmann
- Institut für Industrielle Genetik, Universität Stuttgart, Allmandring 31, 70569, Stuttgart, Germany
| | - Josef Altenbuchner
- Institut für Industrielle Genetik, Universität Stuttgart, Allmandring 31, 70569, Stuttgart, Germany
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13
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A Periplasmic Complex of the Nitrite Reductase NirS, the Chaperone DnaK, and the Flagellum Protein FliC Is Essential for Flagellum Assembly and Motility in Pseudomonas aeruginosa. J Bacteriol 2015; 197:3066-75. [PMID: 26170416 DOI: 10.1128/jb.00415-15] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2015] [Accepted: 07/08/2015] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED Pseudomonas aeruginosa is a ubiquitously occurring environmental bacterium and opportunistic pathogen responsible for various acute and chronic infections. Obviously, anaerobic energy generation via denitrification contributes to its ecological success. To investigate the structural basis for the interconnection of the denitrification machinery to other essential cellular processes, we have sought to identify the protein interaction partners of the denitrification enzyme nitrite reductase NirS in the periplasm. We employed NirS as an affinity-purifiable bait to identify interacting proteins in vivo. Results obtained revealed that both the flagellar structural protein FliC and the protein chaperone DnaK form a complex with NirS in the periplasm. The interacting domains of NirS and FliC were tentatively identified. The NirS-interacting stretch of amino acids lies within its cytochrome c domain. Motility assays and ultrastructure analyses revealed that a nirS mutant was defective in the formation of flagella and correspondingly in swimming motility. In contrast, the fliC mutant revealed an intact denitrification pathway. However, deletion of the nirF gene, coding for a heme d1 biosynthetic enzyme, which leads to catalytically inactive NirS, did not abolish swimming ability. This pointed to a structural function for the NirS protein. FliC and NirS were found colocalized with DnaK at the cell surface of P. aeruginosa. A function of the detected periplasmic NirS-DnaK-FliC complex in flagellum formation and motility was concluded and discussed. IMPORTANCE Physiological functions in Gram-negative bacteria are connected with the cellular compartment of the periplasm and its membranes. Central enzymatic steps of anaerobic energy generation and the motility mediated by flagellar activity use these cellular structures in addition to multiple other processes. Almost nothing is known about the protein network functionally connecting these processes in the periplasm. Here, we demonstrate the existence of a ternary complex consisting of the denitrifying enzyme NirS, the chaperone DnaK, and the flagellar protein FliC in the periplasm of the pathogenic bacterium P. aeruginosa. The dependence of flagellum formation and motility on the presence of an intact NirS was shown, structurally connecting both cellular processes, which are important for biofilm formation and pathogenicity of the bacterium.
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14
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Ringel P, Probst C, Dammeyer T, Buchmeier S, Jänsch L, Wissing J, Tinnefeld P, Mendel RR, Jockusch BM, Kruse T. Enzymatic characterization of recombinant nitrate reductase expressed and purified from Neurospora crassa. Fungal Genet Biol 2015; 80:10-8. [PMID: 25914160 DOI: 10.1016/j.fgb.2015.04.016] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2015] [Accepted: 04/13/2015] [Indexed: 01/14/2023]
Abstract
We established an expression and purification procedure for recombinant protein production in Neurospora crassa (N. crassa). This Strep-tag® based system was successfully used for purifying recombinant N. crassa nitrate reductase (NR), whose enzymatic activity was compared to recombinant N. crassa NR purified from Escherichia coli. The purity of the two different NR preparations was similar but NR purified from N. crassa showed a significantly higher nitrate turnover rate. Two phosphorylation sites were identified for NR purified from the endogenous expression system. We conclude that homologous expression of N. crassa NR yields a higher active enzyme and propose that NR phosphorylation causes enhanced enzymatic activity.
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Affiliation(s)
- Phillip Ringel
- Department of Plant Biology, Braunschweig University of Technology, 38106 Braunschweig, Germany
| | - Corinna Probst
- Department of Plant Biology, Braunschweig University of Technology, 38106 Braunschweig, Germany
| | - Thorben Dammeyer
- Department of Physical and Theoretical Chemistry and Braunschweig Integrated Center of Systems Biology (BRICS), Braunschweig University of Technology, 38106 Braunschweig, Germany
| | - Sabine Buchmeier
- Department of Physical and Theoretical Chemistry and Braunschweig Integrated Center of Systems Biology (BRICS), Braunschweig University of Technology, 38106 Braunschweig, Germany
| | - Lothar Jänsch
- Cellular Proteomics, Helmholtz Centre for Infection Research, 38124 Braunschweig, Germany
| | - Josef Wissing
- Cellular Proteomics, Helmholtz Centre for Infection Research, 38124 Braunschweig, Germany
| | - Philip Tinnefeld
- Department of Physical and Theoretical Chemistry and Braunschweig Integrated Center of Systems Biology (BRICS), Braunschweig University of Technology, 38106 Braunschweig, Germany
| | - Ralf R Mendel
- Department of Plant Biology, Braunschweig University of Technology, 38106 Braunschweig, Germany
| | - Brigitte M Jockusch
- Zoological Institute, Braunschweig University of Technology, 38106 Braunschweig, Germany
| | - Tobias Kruse
- Department of Plant Biology, Braunschweig University of Technology, 38106 Braunschweig, Germany.
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15
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Djender S, Schneider A, Beugnet A, Crepin R, Desrumeaux KE, Romani C, Moutel S, Perez F, de Marco A. Bacterial cytoplasm as an effective cell compartment for producing functional VHH-based affinity reagents and Camelidae IgG-like recombinant antibodies. Microb Cell Fact 2014; 13:140. [PMID: 25223348 PMCID: PMC4172947 DOI: 10.1186/s12934-014-0140-1] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2014] [Accepted: 09/08/2014] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND The isolation of recombinant antibody fragments from displayed libraries represents a powerful alternative to the generation of IgGs using hybridoma technology. The selected antibody fragments can then be easily engineered into (multi)-tagged constructs of variable mass and complexity as well as reconstituted into Camelidae IgG-like molecules when expressed fused to Fc domains. Nevertheless, all antibody constructs depend on an oxidizing environment for correct folding and consequently still belong to the proteins difficult to express in bacteria. In such organisms they are mostly produced at low yields in the periplasmic space. RESULTS We demonstrate that fusion constructs of recombinant antibodies in combination with multiple tags can be produced at high yields and totally functional in the cytoplasm of bacteria expressing sulfhydryl oxidase. The method was applied to structurally demanding molecules such as VHHs fused to SNAP and Fc domains and was validated using the antibody-derived reagents in a variety of immune techniques (FACS, ELISA, WB, IP, SPR, and IF). CONCLUSIONS The collected data demonstrate the feasibility of a method that establishes a totally new approach for producing rapidly and inexpensively functional Camelidae IgG-like monoclonal antibodies and antibody-based reagents containing multiple disulfide bonds and suitable for both basic research and clinical applications.
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16
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The Biotechnological Applications of Recombinant Single-Domain Antibodies are Optimized by the C-Terminal Fusion to the EPEA Sequence (C Tag). Antibodies (Basel) 2014. [DOI: 10.3390/antib3020182] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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17
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Siegemund M, Richter F, Seifert O, Unverdorben F, Kontermann RE. Expression and purification of recombinant antibody formats and antibody fusion proteins. Methods Mol Biol 2014; 1131:273-295. [PMID: 24515473 DOI: 10.1007/978-1-62703-992-5_18] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
In the laboratory-scale production of antibody fragments or antibody fusion proteins, it is often difficult to keep track on the most suitable affinity tags for protein purification from either prokaryotic or eukaryotic host systems. Here, we describe how such recombinant proteins derived from Escherichia coli lysates as well as HEK293 cell culture supernatants are purified by IMAC and by different affinity chromatography methods based on fusions to FLAG-tag, Strep-tag, and Fc domains.
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Affiliation(s)
- Martin Siegemund
- Institut für Zellbiologie und Immunologie, Universität Stuttgart, Stuttgart, Germany
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18
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Bi C, Su P, Müller J, Yeh YC, Chhabra SR, Beller HR, Singer SW, Hillson NJ. Development of a broad-host synthetic biology toolbox for Ralstonia eutropha and its application to engineering hydrocarbon biofuel production. Microb Cell Fact 2013; 12:107. [PMID: 24219429 PMCID: PMC3831590 DOI: 10.1186/1475-2859-12-107] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2013] [Accepted: 11/11/2013] [Indexed: 01/20/2023] Open
Abstract
Background The chemoautotrophic bacterium Ralstonia eutropha can utilize H2/CO2 for growth under aerobic conditions. While this microbial host has great potential to be engineered to produce desired compounds (beyond polyhydroxybutyrate) directly from CO2, little work has been done to develop genetic part libraries to enable such endeavors. Results We report the development of a toolbox for the metabolic engineering of Ralstonia eutropha H16. We have constructed a set of broad-host-range plasmids bearing a variety of origins of replication, promoters, 5’ mRNA stem-loop structures, and ribosomal binding sites. Specifically, we analyzed the origins of replication pCM62 (IncP), pBBR1, pKT (IncQ), and their variants. We tested the promoters PBAD, T7, Pxyls/PM, PlacUV5, and variants thereof for inducible expression. We also evaluated a T7 mRNA stem-loop structure sequence and compared a set of ribosomal binding site (RBS) sequences derived from Escherichia coli, R. eutropha, and a computational RBS design tool. Finally, we employed the toolbox to optimize hydrocarbon production in R. eutropha and demonstrated a 6-fold titer improvement using the appropriate combination of parts. Conclusion We constructed and evaluated a versatile synthetic biology toolbox for Ralstonia eutropha metabolic engineering that could apply to other microbial hosts as well.
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Affiliation(s)
| | | | | | | | - Swapnil R Chhabra
- Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.
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