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Agranier E, Crétin P, Joublin-Delavat A, Veillard L, Touahri K, Delavat F. Development and utilization of new O 2-independent bioreporters. Microbiol Spectr 2024; 12:e0409123. [PMID: 38441526 PMCID: PMC10986488 DOI: 10.1128/spectrum.04091-23] [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: 12/01/2023] [Accepted: 02/19/2024] [Indexed: 04/06/2024] Open
Abstract
Fluorescent proteins have revolutionized science since their discovery in 1962. They have enabled imaging experiments to decipher the function of proteins, cells, and organisms, as well as gene regulation. Green fluorescent protein and all its derivatives are now standard tools in cell biology, immunology, molecular biology, and microbiology laboratories around the world. A common feature of these proteins is their dioxygen (O2)-dependent maturation allowing fluorescence, which precludes their use in anoxic contexts. In this work, we report the development and in cellulo characterization of genetic circuits encoding the O2-independent KOFP-7 protein, a flavin-binding fluorescent protein. We have optimized the genetic circuit for high bacterial fluorescence at population and single-cell level, implemented this circuit in various plasmids differing in host range, and quantified their fluorescence under both aerobic and anaerobic conditions. Finally, we showed that KOFP-7-based constructions can be used to produce fluorescing cells of Vibrio diazotrophicus, a facultative anaerobe, demonstrating the usefulness of the genetic circuits for various anaerobic bacteria. These genetic circuits can thus be modified at will, both to solve basic and applied research questions, opening a highway to shed light on the obscure anaerobic world.IMPORTANCEFluorescent proteins are used for decades, and have allowed major discoveries in biology in a wide variety of fields, and are used in environmental as well as clinical contexts. Green fluorescent protein (GFP) and all its derivatives share a common feature: they rely on the presence of dioxygen (O2) for protein maturation and fluorescence. This dependency precludes their use in anoxic environments. Here, we constructed a series of genetic circuits allowing production of KOFP-7, an O2-independant flavin-binding fluorescent protein. We demonstrated that Escherichia coli cells producing KOFP-7 are fluorescent, both at the population and single-cell levels. Importantly, we showed that, unlike cells producing GFP, cells producing KOFP-7 are fluorescent in anoxia. Finally, we demonstrated that Vibrio diazotrophicus NS1, a facultative anaerobe, is fluorescent in the absence of O2 when KOFP-7 is produced. Altogether, the development of new genetic circuits allowing O2-independent fluorescence will open new perspective to study anaerobic processes.
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Affiliation(s)
- Eva Agranier
- Nantes Université, CNRS, US2B, UMR6286, Nantes, France
| | | | | | - Léa Veillard
- Nantes Université, CNRS, US2B, UMR6286, Nantes, France
| | - Katia Touahri
- Nantes Université, CNRS, US2B, UMR6286, Nantes, France
- Laboratoire Chimie et Biochimie de Molécules Bioactives, Université de Strasbourg/CNRS, UMR7177, Strasbourg, France
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2
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Chen Y, Guo Y, Liu Y, Xiang Y, Liu G, Zhang Q, Yin Y, Cai Y, Jiang G. Advances in bacterial whole-cell biosensors for the detection of bioavailable mercury: A review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 868:161709. [PMID: 36682565 DOI: 10.1016/j.scitotenv.2023.161709] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Revised: 12/29/2022] [Accepted: 01/15/2023] [Indexed: 06/17/2023]
Abstract
Mercury (Hg) and its organic compounds, especially monomethylmercury (MeHg), cause major damage to the ecosystem and human health. In surface water or sediments, microorganisms play a crucial role in the methylation and demethylation of Hg. Given that Hg transformation processes are intracellular reactions, accurate assessment of the bioavailability of Hg(II)/MeHg in the environment, particularly for microorganisms, is of major importance. Compared with traditional analytical methods, bacterial whole-cell biosensors (BWCBs) provide a more accurate, convenient, and cost-effective strategy to assess the environmental risks of Hg(II)/MeHg. This Review summarizes recent progress in the application of BWCBs in the detection of bioavailable Hg(II)/MeHg, providing insight on current challenges and strategies. The principle and components of BWCBs for Hg(II)/MeHg bioavailability analysis are introduced. Furthermore, the impact of water chemical factors on the bioavailability of Hg is discussed as are future perspectives of BWCBs in bioavailable Hg analysis and optimization of BWCBs.
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Affiliation(s)
- Yueqian Chen
- School of Environment, Hangzhou Institute for Advanced Study, UCAS, Hangzhou 310024, China
| | - Yingying Guo
- Laboratory of Environmental Nanotechnology and Health, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Yanwei Liu
- Laboratory of Environmental Nanotechnology and Health, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Yuping Xiang
- Laboratory of Environmental Nanotechnology and Health, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
| | - Guangliang Liu
- Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199, United States of America
| | - Qinghua Zhang
- School of Environment, Hangzhou Institute for Advanced Study, UCAS, Hangzhou 310024, China; State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Yongguang Yin
- School of Environment, Hangzhou Institute for Advanced Study, UCAS, Hangzhou 310024, China; Laboratory of Environmental Nanotechnology and Health, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Yong Cai
- Laboratory of Environmental Nanotechnology and Health, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199, United States of America
| | - Guibin Jiang
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
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3
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Xiang Y, Guo Y, Liu G, Liu Y, Song M, Shi J, Hu L, Yin Y, Cai Y, Jiang G. Particle-Bound Hg(II) is Available for Microbial Uptake as Revealed by a Whole-Cell Biosensor. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:6754-6764. [PMID: 35502862 DOI: 10.1021/acs.est.1c08946] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Particle-bound mercury (HgP), ubiquitously present in aquatic environments, can be methylated into highly toxic methylmercury, but it remains challenging to assess its bioavailability. In this study, we developed anEscherichia coli-based whole-cell biosensor to probe the microbial uptake of inorganic Hg(II) and assess the bioavailability of HgP sorbed on natural and model particles. This biosensor can quantitatively distinguish the contribution of dissolved Hg(II) and HgP to intracellular Hg. Results showed that the microbial uptake of HgP was ubiquitous in the environment, as evidenced by the bioavailability of sorbed-Hg(II) onto particulate matter and model particles (Fe2O3, Fe3O4, Al2O3, and SiO2). In both oxic and anoxic environments, HgP was an important Hg(II) source for microbial uptake, with enhanced bioavailability under anoxic conditions. The composition of particles significantly affected the microbial uptake of HgP, with higher bioavailability being observed for Fe2O3 and lower for Al2O3 particles. The bioavailability of HgP varied also with the size of particles. In addition, coating with humic substances and model organic compound (cysteine) on Fe2O3 particles decreased the bioavailability of HgP. Overall, our findings highlight the role of HgP in Hg biogeochemical cycling and shed light on the enhanced Hg-methylation in settling particles and sediments in aquatic environments.
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Affiliation(s)
- Yuping Xiang
- Laboratory of Environmental Nanotechnology and Health Effect, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yingying Guo
- Laboratory of Environmental Nanotechnology and Health Effect, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Guangliang Liu
- Department of Chemistry and Biochemistry, Florida International University, Miami, Florida 33199, United States
- Institute of Environment and Health, Jianghan University, Wuhan 430056, China
| | - Yanwei Liu
- Laboratory of Environmental Nanotechnology and Health Effect, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Maoyong Song
- Laboratory of Environmental Nanotechnology and Health Effect, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Jianbo Shi
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Ligang Hu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Yongguang Yin
- Laboratory of Environmental Nanotechnology and Health Effect, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- University of Chinese Academy of Sciences, Beijing 100049, China
- Institute of Environment, Hangzhou Institute for Advanced Study, UCAS, Hangzhou 310024, China
| | - Yong Cai
- Laboratory of Environmental Nanotechnology and Health Effect, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- Department of Chemistry and Biochemistry, Florida International University, Miami, Florida 33199, United States
| | - Guibin Jiang
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
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4
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Xiang Y, Zhu A, Guo Y, Liu G, Chen B, He B, Liang Y, Yin Y, Cai Y, Jiang G. Decreased bioavailability of both inorganic mercury and methylmercury in anaerobic sediments by sorption on iron sulfide nanoparticles. JOURNAL OF HAZARDOUS MATERIALS 2022; 424:127399. [PMID: 34638072 DOI: 10.1016/j.jhazmat.2021.127399] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Revised: 09/07/2021] [Accepted: 09/28/2021] [Indexed: 06/13/2023]
Abstract
Methylmercury (MeHg), derived via inorganic mercury (Hg(II)) methylation by anaerobic microorganisms, is a neurotoxic contaminant causing concern worldwide. Establishing how to reduce Hg(II) methylation and MeHg bioavailability is essential for effective control of Hg pollution. Iron sulfide nanoparticles (FeSNP) is a promising passivator for Hg(II) methylation. However, its effect on the fate of MeHg in aquatic systems remains poorly understood. This study investigated the effect of FeSNP on Hg(II) bioavailability, MeHg production and bioavailability in aquatic environments. Results demonstrated that FeSNP rapidly sorbed Hg(II) and MeHg, with sorption affected by pH, chloride ion and dissolved organic matter. Hg-specific biosensor analysis showed that Hg(II) sorbed onto FeSNP significantly reduced its bioavailability to microorganisms. Double stable isotope (199Hg(II) and Me201Hg) addition revealed that FeSNP significantly inhibited MeHg production in anaerobic sediments. Furthermore, synthetic gut juice extraction suggested that FeSNP decrease concentrations of bioavailable MeHg and Hg(II), reducing their integration into food webs. However, the sorbed MeHg and Hg(II) in sediments can be released after FeSNP oxidation, potentially enhancing the risk of exposure to aquatic organisms. Overall, these findings increase our understanding of Hg transformation and exposure risks in aquatic systems, providing valuable information for the development of in situ Hg remediation systems.
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Affiliation(s)
- Yuping Xiang
- Laboratory of Environmental Nanotechnology and Health Effect, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Ailing Zhu
- Laboratory of Environmental Nanotechnology and Health Effect, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Yingying Guo
- Laboratory of Environmental Nanotechnology and Health Effect, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Guangliang Liu
- Department of Chemistry & Biochemistry and Southeast Environmental Research Center, Florida International University, 11200 SW 8th ST, Miami, FL 33199, USA
| | - Baowei Chen
- Southern Marine Science and Engineering Guangdong Laboratory, School of Marine Sciences, Sun Yat-Sen University, Zhuhai 519082, China
| | - Bin He
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Yong Liang
- Institute of Environment and Health, Jianghan University, Wuhan 430056, China
| | - Yongguang Yin
- Laboratory of Environmental Nanotechnology and Health Effect, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China; Institute of Environment and Health, Jianghan University, Wuhan 430056, China; Institute of Environment and Health, Hangzhou Institute for Advanced Study, UCAS, Hangzhou 310024, China.
| | - Yong Cai
- Laboratory of Environmental Nanotechnology and Health Effect, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; Department of Chemistry & Biochemistry and Southeast Environmental Research Center, Florida International University, 11200 SW 8th ST, Miami, FL 33199, USA
| | - Guibin Jiang
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
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5
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Anaerobic fluorescent reporters for cell identification, microbial cell biology and high-throughput screening of microbiota and genomic libraries. Curr Opin Biotechnol 2021; 71:151-163. [PMID: 34375813 DOI: 10.1016/j.copbio.2021.07.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Accepted: 07/08/2021] [Indexed: 11/23/2022]
Abstract
The lack of real-time reporters in obligate anaerobes has limited studies in gene expression, promoter characterization, library screening, population dynamics, and cell biology in these organisms. While the use of enzymatic, colorimetric, and luminescent reporters has been reported, the need for reliable anaerobic fluorescent proteins is widely acknowledged. Recently, the fluorescent proteins HaloTag, SNAP-tag and FAST have been established as reliable reporters in Clostridium spp., thus suggesting that these reporters can be adopted widely for many obligate anaerobes. With a multitude of labeling options, these anaerobic fluorescent proteins hold a great potential for screening promoters, terminators, and RBS sites, tracking population dynamics in complex multi-species co-cultures, such as microbiomes, screening libraries, and in cell biology studies of protein localization and interactions using high-resolution microscopy.
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6
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Kotlobay AA, Kaskova ZM, Yampolsky IV. Palette of Luciferases: Natural Biotools for New Applications in Biomedicine. Acta Naturae 2020; 12:15-27. [PMID: 32742724 PMCID: PMC7385095 DOI: 10.32607/actanaturae.10967] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Accepted: 04/29/2020] [Indexed: 12/30/2022] Open
Abstract
Optoanalytical methods based on using genetically encoded bioluminescent enzymes, luciferases, allow one to obtain highly sensitive signals, are non-invasive, and require no external irradiation. Bioluminescence is based on the chemical reaction of oxidation of a low-molecular-weight substrate (luciferin) by atmospheric oxygen, which is catalyzed by an enzyme (luciferase). Relaxation of the luciferin oxidation product from its excited state is accompanied by a release of a quantum of light, which can be detected as an analytical signal. The ability to express luciferase genes in various heterological systems and high quantum yields of luminescence reactions have made these tools rather popular in biology and medicine. Among several naturally available luciferases, a few have been found to be useful for practical application. Luciferase size, the wavelength of its luminescence maximum, enzyme thermostability, optimal pH of the reaction, and the need for cofactors are parameters that may differ for luciferases from different groups of organisms, and this fact directly affects the choice of the application area for each enzyme. It is quite important to overview the whole range of currently available luciferases based on their biochemical properties before choosing one bioluminescent probe suitable for a specific application.
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Affiliation(s)
- A. A. Kotlobay
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry of the Russian Academy of Sciences, Moscow, 117997 Russia
| | - Z. M. Kaskova
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry of the Russian Academy of Sciences, Moscow, 117997 Russia
- Pirogov Russian National Research Medical University, Moscow, 117997 Russia
| | - I. V. Yampolsky
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry of the Russian Academy of Sciences, Moscow, 117997 Russia
- Pirogov Russian National Research Medical University, Moscow, 117997 Russia
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7
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Kuehne SA, Rood JI, Lyras D. Clostridial Genetics: Genetic Manipulation of the Pathogenic Clostridia. Microbiol Spectr 2019; 7:10.1128/microbiolspec.gpp3-0040-2018. [PMID: 31172914 PMCID: PMC11315012 DOI: 10.1128/microbiolspec.gpp3-0040-2018] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Indexed: 02/07/2023] Open
Abstract
The past 10 years have been revolutionary for clostridial genetics. The rise of next-generation sequencing led to the availability of annotated whole-genome sequences of the important pathogenic clostridia: Clostridium perfringens, Clostridioides (Clostridium) difficile, and Clostridium botulinum, but also Paeniclostridium (Clostridium) sordellii and Clostridium tetani. These sequences were a prerequisite for the development of functional, sophisticated genetic tools for the pathogenic clostridia. A breakthrough came in the early 2000s with the development of TargeTron-based technologies specific for the clostridia, such as ClosTron, an insertional gene inactivation tool. The following years saw a plethora of new technologies being developed, mostly for C. difficile, but also for other members of the genus, including C. perfringens. A range of tools is now available, allowing researchers to precisely delete genes, change single nucleotides in the genome, complement deletions, integrate novel DNA into genomes, or overexpress genes. There are tools for forward genetics, including an inducible transposon mutagenesis system for C. difficile. As the latest addition to the tool kit, clustered regularly interspaced short palindromic repeat (CRISPR)-Cas9 technologies have also been adopted for the construction of single and multiple gene deletions in C. difficile. This article summarizes the key genetic technologies available to manipulate, study, and understand the pathogenic clostridia.
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Affiliation(s)
- S A Kuehne
- School of Dentistry and Institute for Microbiology and Infection, University of Birmingham, Birmingham, UK
| | - J I Rood
- Infection and Immunity Program, Monash Biomedicine Discovery Institute and Department of Microbiology, Monash University, Clayton, Victoria, Australia 3800
| | - D Lyras
- Infection and Immunity Program, Monash Biomedicine Discovery Institute and Department of Microbiology, Monash University, Clayton, Victoria, Australia 3800
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8
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Wakabayashi Y, Nariya H, Yasugi M, Kuwahara T, Sarker MR, Miyake M. An enhanced green fluorescence protein (EGFP)-based reporter assay for quantitative detection of sporulation in Clostridium perfringens SM101. Int J Food Microbiol 2018; 291:144-150. [PMID: 30500691 DOI: 10.1016/j.ijfoodmicro.2018.11.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Revised: 10/17/2018] [Accepted: 11/17/2018] [Indexed: 11/16/2022]
Abstract
Clostridium perfringens type F is a spore-forming anaerobe that causes bacterial food-borne illness in humans. The disease develops when ingested vegetative cells reach the intestinal tract and begin to form spores that produce the diarrheagenic C. perfringens enterotoxin (CPE). Given that CPE production is regulated by the master regulator of sporulation (transcription factor Spo0A), the identification of sporulation-inducing factors in the intestine is relevant to better understanding of the disease. To examine these factors, we established assays to quantify C. perfringens sporulation stage under microscopy by using two fluorescent reporters, namely, Evoglow-Bs2 and CpEGFP. When the reporter genes were placed under control of the cpe promoter, both protein products were expressed specifically during sporulation. However, the intensity of the anaerobic reporter Evoglow-Bs2 was weak and rapidly photobleached during microscopic observation. Alternatively, CpEGFP, a canonical green fluorescence protein with optimized codon usage for Clostridium species, was readily detectable in the mother-cell compartment of most bacteria at early stages of sporulation. Additionally, CpEGFP expression predicted final spore yield and was quantifiable in 96-well plates using fluorescence plate reader. These results indicate that CpEGFP can be used to analyze the sporulation of C. perfringens and has a potential application in the large-scale screening of sporulation-regulating biomolecules.
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Affiliation(s)
- Yuki Wakabayashi
- Graduate School of Life and Environmental Sciences, Osaka Prefecture University, 1-58 Rinku Ourai Kita, Izumisano, Osaka 598-8531, Japan
| | - Hirofumi Nariya
- Department of Microbiology, Faculty of Medicine, Kagawa University, 1750-1 Miki-cho, Kita-gun, Kagawa 761-0793, Japan
| | - Mayo Yasugi
- Graduate School of Life and Environmental Sciences, Osaka Prefecture University, 1-58 Rinku Ourai Kita, Izumisano, Osaka 598-8531, Japan
| | - Tomomi Kuwahara
- Department of Microbiology, Faculty of Medicine, Kagawa University, 1750-1 Miki-cho, Kita-gun, Kagawa 761-0793, Japan
| | - Mahfuzur R Sarker
- Department of Biomedical Sciences, Department of Microbiology, Oregon State University, Corvallis, Oregon 97331, USA
| | - Masami Miyake
- Graduate School of Life and Environmental Sciences, Osaka Prefecture University, 1-58 Rinku Ourai Kita, Izumisano, Osaka 598-8531, Japan.
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9
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O 2-requiring molecular reporters of gene expression for anaerobic microorganisms. Biosens Bioelectron 2018; 123:1-6. [PMID: 30269005 DOI: 10.1016/j.bios.2018.09.066] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Revised: 09/13/2018] [Accepted: 09/19/2018] [Indexed: 12/15/2022]
Abstract
Many genetic reporter systems require molecular oxygen; therefore, the use of reporter genes to study molecular mechanisms in anaerobic microorganisms has been hampered by the lack of convenient reporting systems. We describe reporter gene whole cell-based biosensor systems based on luciferase genes and the associated oxygen-requiring enzymes. By using two different oxygen-dependent reporters, insect and bacterial luciferases, and two bacterial hosts, Gram (+) Bifidobacterium longum and Gram (-) Escherichia coli, we show that the enzymes can be used in gene expression studies of anaerobic bacteria. E. coli, a facultative anaerobe, was grown both in aerobic and anaerobic conditions with an arabinose-inducible expression system. We show that a short treatment time of few minutes in ambient atmosphere is sufficient to detect light emission from living cells that is directly proportional to the number of cells and to the inducer concentration. The induction levels were the same in both the aerobically and anaerobically cultured cells. Similar results were obtained in the case of B. longum cultured in anaerobic conditions.
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10
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Ninomiya K, Yamada R, Matsumoto M, Fukiya S, Katayama T, Ogino C, Shimizu N. Image analyzing method to evaluate in situ bioluminescence from an obligate anaerobe cultivated under various dissolved oxygen concentrations. J Biosci Bioeng 2012; 115:196-9. [PMID: 23040354 DOI: 10.1016/j.jbiosc.2012.09.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2012] [Revised: 09/04/2012] [Accepted: 09/05/2012] [Indexed: 01/04/2023]
Abstract
An image analyzing method was developed to evaluate in situ bioluminescence expression, without exposing the culture sample to the ambient oxygen atmosphere. Using this method, we investigated the effect of dissolved oxygen concentration on bioluminescence from an obligate anaerobe Bifidobacterium longum expressing bacterial luciferase which catalyzes an oxygen-requiring bioluminescent reaction.
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Affiliation(s)
- Kazuaki Ninomiya
- Institute of Nature and Environmental Technology, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan
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11
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Mastropaolo MD, Thorson ML, Stevens AM. Comparison of Bacteroides thetaiotaomicron and Escherichia coli 16S rRNA gene expression signals. MICROBIOLOGY-SGM 2009; 155:2683-2693. [PMID: 19443545 DOI: 10.1099/mic.0.027748-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
There are barriers to cross-expression of genes between Bacteroides spp. and Escherichia coli. In this study, a lux-based reporter system was developed for Bacteroides and used to compare the promoter structure and function of a Bacteroides thetaiotaomicron 4001 (BT4001) 16S rRNA promoter with those of E. coli in vivo. Analysis of the BT4001 sequences upstream of the 16S rRNA gene revealed the same overall structure known for E. coli 16S rRNA promoters in that there were two promoters separated by approximately 150 bp. However, the BT4001 16S rRNA promoter contains the proposed Bacteroides -7 and -33 consensus sequences instead of the E. coli -10 and -35 consensus sequences. The biological activity of various configurations of the BT4001 16S rRNA promoter was analysed. Experiments pairing the BT4001 16S rRNA promoter with an E. coli RBS, and vice-versa, confirmed that gene expression between the two species is restricted at the level of transcription. In Bacteroides, a difference in translation initiation also appears to limit expression of foreign genes.
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MESH Headings
- Bacteroides/genetics
- Bacteroides/metabolism
- Base Sequence
- Consensus Sequence
- DNA, Bacterial/analysis
- DNA, Bacterial/genetics
- Escherichia coli/genetics
- Escherichia coli/metabolism
- Gene Expression
- Genes, Reporter
- Genes, rRNA
- Luminescent Measurements/methods
- Molecular Sequence Data
- Photorhabdus/genetics
- Promoter Regions, Genetic
- RNA, Ribosomal, 16S/genetics
- RNA, Ribosomal, 16S/metabolism
- Sequence Analysis, DNA
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Affiliation(s)
- Matthew D Mastropaolo
- Department of Biological Sciences, Virginia Tech, 219 Life Sciences 1, Washington Street, Blacksburg, VA 24061-0910, USA
| | - Mary L Thorson
- Department of Biological Sciences, Virginia Tech, 219 Life Sciences 1, Washington Street, Blacksburg, VA 24061-0910, USA
| | - Ann M Stevens
- Department of Biological Sciences, Virginia Tech, 219 Life Sciences 1, Washington Street, Blacksburg, VA 24061-0910, USA
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Feustel L, Nakotte S, Dürre P. Characterization and development of two reporter gene systems for Clostridium acetobutylicum. Appl Environ Microbiol 2004; 70:798-803. [PMID: 14766557 PMCID: PMC348925 DOI: 10.1128/aem.70.2.798-803.2004] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The use of lacZ from Thermoanaerobacterium thermosulfurigenes (encoding beta-galactosidase) and lucB from Photinus pyralis (encoding luciferase) as reporter genes in Clostridium acetobutylicum was analyzed with promoters of genes required for solventogenesis and acidogenesis. Both systems proved to be well suited and allowed the detection of differences in promoter strength at least up to 100-fold. The luciferase assay could be performed much faster and comes close to online measurement. Resequencing of lacZ revealed a sequence error in the original database entry, which resulted in beta-galactosidase with an additional 31 amino acids. Cutting off part of the gene encoding this C terminus resulted in decreased enzyme activity. The lacZ reporter data showed that bdhA (encoding butanol dehydrogenase A) is expressed during the early growth phase, followed by sol (encoding butyraldehyde/butanol dehydrogenase E and coenzyme A transferase) and bdhB (encoding butanol dehydrogenase B) expression. adc (encoding acetoacetate decarboxylase) was also induced early. There is about a 100-fold difference in expression between adc and bdhB (higher) and bdhA and the sol operon (lower). The lucB reporter activity could be increased 10-fold by the addition of ATP to the assay. Washing of the cells proved to be important in order to prevent a red shift of bioluminescence in an acidic environment (for reliable data). lucB reporter measurements confirmed the expression pattern of the sol and ptb-buk (encoding phosphotransbutyrylase and butyrate kinase) operons as determined by the lacZ reporter and showed that the expression level from the ptb promoter is 59-fold higher than that from the sol operon promoter.
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Affiliation(s)
- Lothar Feustel
- Mikrobiologie und Biotechnologie, Universität Ulm, 89069 Ulm, Germany
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Hofman-Bang J, Zheng D, Westermann P, Ahring BK, Raskin L. Molecular ecology of anaerobic reactor systems. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2003; 81:151-203. [PMID: 12747563 DOI: 10.1007/3-540-45839-5_5] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Anaerobic reactor systems are essential for the treatment of solid and liquid wastes and constitute a core facility in many waste treatment plants. Although much is known about the basic metabolism in different types of anaerobic reactors, little is known about the microbes responsible for these processes. Only a few percent of Bacteria and Archaea have so far been isolated, and almost nothing is known about the dynamics and interactions between these and other microorganisms. This lack of knowledge is most clearly exemplified by the sometimes unpredictable and unexplainable failures and malfunctions of anaerobic digesters occasionally experienced, leading to sub-optimal methane production and wastewater treatment. Using a variety of molecular techniques, we are able to determine which microorganisms are active, where they are active, and when they are active, but we still need to determine why and what they are doing. As genetic manipulations of anaerobes have been shown in only a few species permitting in-situ gene expression studies, the only way to elucidate the function of different microbes is to correlate the metabolic capabilities of isolated microbes in pure culture to the abundance of each microbe in anaerobic reactor systems by rRNA probing. This chapter focuses on various molecular techniques employed and problems encountered when elucidating the microbial ecology of anaerobic reactor systems. Methods such as quantitative dot blot/fluorescence in-situ probing using various specific nucleic acid probes are discussed and exemplified by studies of anaerobic granular sludge, biofilm and digester systems.
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Affiliation(s)
- J Hofman-Bang
- Environmental Microbiology and Biotechnology, Biocentrum DTU, The Technical University of Denmark, Building 227, 2800 Lyngby, Denmark.
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Phillips-Jones MK. Use of a lux reporter system for monitoring rapid changes in alpha-toxin gene expression in Clostridium perfringens during growth. FEMS Microbiol Lett 2000; 188:29-33. [PMID: 10867230 DOI: 10.1111/j.1574-6968.2000.tb09164.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
To determine whether the luxA-luxB reporter system is suitable as a sensitive reporter for rapid real-time measurements of alpha-toxin gene (cpa) expression in Clostridium perfringens, and to widen the range of alpha-toxin-producing C. perfringens strains examined with respect to cpa expression during growth, the reporter plasmid pPS14 (possessing the alpha-toxin promoter region plus 0.7 kb of upstream region linked to the luxA-luxB genes), was used in batch growth experiments of C. perfringens P90.2.2, an alpha-toxin-producing strain with no known association with disease. Levels of in vivo bioluminescence obtained during growth were broadly in agreement with previous mRNA and reporter studies of cpa expression (Bullifent et al., FEMS Microbiol. Lett. 131 (1995) 99-105), confirming the suitability of lux as an accurate reporter system in this organism, but the sensitive nature of the lux reporter permitted the in vivo detection of a very rapid reduction in expression during late-exponential phase that was not attributable to loss in cell viability or limiting bioluminescence assay substrates. There was also a small peak in cpa expression in early- to mid-exponential phase cells, that was not detected in previous studies with other reporters. This may be indicative of the exquisite sensitivity of the lux reporter, or this may be a difference in cpa expression that occurs specifically in this C. perfringens strain. Whichever is the case, these results confirm the complexity of alpha-toxin gene expression in different strains of this pathogenic bacterium.
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Affiliation(s)
- M K Phillips-Jones
- Division of Microbiology, School of Biochemistry and Molecular Biology, University of Leeds, UK.
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15
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Griffiths MW. How novel methods can help discover more information about foodborne pathogens. Can J Infect Dis 2000; 11:142-53. [PMID: 18159282 PMCID: PMC2094761 DOI: 10.1155/2000/364050] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Considerable emphasis is being placed on quantitative risk assessment modelling as a basis for regulation of trade in food products. However, for models to be accurate, information about the behaviour of potential pathogens in foods needs to be available. The question is how to obtain this knowledge in a simple and cost effective way. One technique that has great potential is the use of reporter bacteria which have been genetically modified to express a phenotype that can be easily monitored, such as light production in luminescent organisms. Bacteria carrying these (lux) genes can easily be detected using simple luminometers or more sophisticated low light imaging equipment.By monitoring light output from these bacteria over time, it can easily be determined if the organism is growing (resulting in an increase in light emission), is dead (causing a decrease in light production) or is injured (light output remains constant). The use of imaging systems allows the response of bioluminescent bacteria to be studied directly on the food, making the technique even more useful. Applications of bioluminescence are discussed below and include use as reporters of gene expression; biocide efficacy and antibiotic susceptibility; sub-lethal injury; adhesion and biofilm formation; the microbial ecology of foods; pathogenesis; and as biosensors.
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Affiliation(s)
- M W Griffiths
- Department of Food Science, University of Guelph, Guelph, Ontario.
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Siragusa GR, Nawotka K, Spilman SD, Contag PR, Contag CH. Real-time monitoring of Escherichia coli O157:H7 adherence to beef carcass surface tissues with a bioluminescent reporter. Appl Environ Microbiol 1999; 65:1738-45. [PMID: 10103275 PMCID: PMC91245 DOI: 10.1128/aem.65.4.1738-1745.1999] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/1998] [Accepted: 11/27/1998] [Indexed: 11/20/2022] Open
Abstract
A method for studying bacteria that are attached to carcass surfaces would eliminate the need for exogenous sampling and would facilitate understanding the interaction of potential human food-borne pathogens with food animal tissue surfaces. We describe such a method in which we used a bioluminescent reporter strain of Escherichia coli O157:H7 that was constructed by transformation with plasmid pCGLS1, an expression vector that contains a complete bacterial luciferase (lux) operon. Beef carcass surface tissues were inoculated with the bioluminescent strain, and adherent bacteria were visualized in real time by using a sensitive photon-counting camera to obtain in situ images. The reporter strain was found to luminesce from the tissue surfaces whether it was inoculated as a suspension in buffer or as a suspension in a bovine fecal slurry. With this method, areas of tissues inoculated with the reporter strain could be studied without obtaining, excising, homogenizing, and culturing multiple samples from the tissue surface. Use of the complete lux operon as the bioluminescent reporter eliminated the need to add exogenous substrate. This allowed detection and quantitation of bacterial inocula and rapid evaluation of adherence of a potential human pathogen to tissue surfaces. Following simple water rinses of inoculated carcass tissues, the attachment duration varied with different carcass surface types. On average, the percent retention of bioluminescent signal from the reporter strain was higher on lean fascia-covered tissue (54%) than on adipose fascia-covered tissue (18%) following water washing of the tissues. Bioluminescence and culture-derived viable bacterial counts were highly correlated (r2 = 0.98). Real-time assessment of microbial attachment to this complex menstruum should facilitate evaluation of carcass decontamination procedures and mechanistic studies of microbial contamination of beef carcass tissues.
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Affiliation(s)
- G R Siragusa
- United States Department of Agriculture, Agricultural Research Service, Roman L. Hruska U.S. Meat Animal Research Center, Clay Center, Nebraska 68933-0166, USA.
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6 Genetic Methods in Clostridia. METHODS IN MICROBIOLOGY 1999. [DOI: 10.1016/s0580-9517(08)70117-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
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Billard P, DuBow MS. Bioluminescence-based assays for detection and characterization of bacteria and chemicals in clinical laboratories. Clin Biochem 1998; 31:1-14. [PMID: 9559218 DOI: 10.1016/s0009-9120(97)00136-7] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
OBJECTIVES To survey recent advances in the application of bioluminescence to public health problems. The usefulness of bacterial (lux) and eucaryotic (luc) luciferase genes is presented, along with several examples that demonstrate their value as "reporters" of many endpoints of clinical concern. CONCLUSIONS The development of new technologies for monitoring biological and chemical contaminants is in continuous progress. Recent excitement in this area has come from the use of genes encoding enzymes for bioluminescence as reporter systems. Applications of the recombinant luciferase reporter phage concept now provide a sensitive approach for bacterial detection, their viability, and sensitivity to antimicrobial agents. Moreover, a number of fusions of the lux and luc genes to stress inducible genes in different bacteria can allow a real-time measurement of gene expression and determination of cellular viability, and also constitute a new tool to detect toxic chemicals and their bioavailability.
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Affiliation(s)
- P Billard
- Centre des Sciences de l'Environnement, Université de Metz, France
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Stewart GSAB. Challenging food microbiology from a molecular perspective. MICROBIOLOGY (READING, ENGLAND) 1997; 143 ( Pt 7):2099-2108. [PMID: 9245799 DOI: 10.1099/00221287-143-7-2099] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Summary: Two key themes within food microbiology are bacterial detection and control. There is a raft of sub-headings under each of these themes, but in the last decade molecular approaches within each have made a significant contribution to the field. This is a personal review of the author’s past and present contributions and future ideas for challenging food microbiology from a molecular perspective.
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Affiliation(s)
- Gordon S A B Stewart
- Department of Applied Biochemistry and Food Science, University of Nottinqham Sutton Bonington Campus, Leicestershire LE12 5RD, UK
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Chatterjee J, Meighen EA. BIOTECHNOLOGICAL APPLICATIONS OF BACTERIAL BIOLUMINESCENCE (lux) GENES. Photochem Photobiol 1995. [DOI: 10.1111/j.1751-1097.1995.tb08711.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Bullifent HL, Moir A, Titball RW. The construction of a reporter system and use for the investigation of Clostridium perfringens gene expression. FEMS Microbiol Lett 1995; 131:99-105. [PMID: 7557317 DOI: 10.1111/j.1574-6968.1995.tb07761.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
A reporter system was constructed to enable the study of gene expression in Clostridium perfingens. The system was based on plasmid shuttle vector pJIR410, which contained the C. perfringens erythromycin resistance gene. The vector was modified by the introduction of a DNA fragment comprising the open reading frame of the C. perfringens chloramphenicol acetyltransferase gene and flanking transcriptional terminators. The presence of a unique restriction site, engineered into the extreme 5' end of the open reading frame enabled a promoter region to be inserted to form an in-fram transcriptional fusion with catP. The system was tested by inserting the promoter region of the alpha-toxin gene of C. perfringens. The production of chloramphenicol acetyltransferase in C. perfringens was monitored during growth and the pattern of expression was shown to reflect levels of plc mRNA and alpha-toxin in the parent strain.
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Affiliation(s)
- H L Bullifent
- Chemical and Biological Defence Establishment, Porton Down, Salisbury, UK
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Marincs F, White DW. Immobilization of Escherichia coli expressing the lux genes of Xenorhabdus luminescens. Appl Environ Microbiol 1994; 60:3862-3. [PMID: 7986053 PMCID: PMC201896 DOI: 10.1128/aem.60.10.3862-3863.1994] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
The luxCDABE operon of Xenorhabdus luminescens was cloned into pUC18 to make pLITE27. Expression of the lux genes from the lac promoter resulted in strong constitutive light emission by Escherichia coli DH5 carrying the recombinant lux plasmid, pLITE27. When strain DH5(pLITE27) was immobilized with sodium alginate-CaCl2, the embedded cells retained their luminescence up to 2 weeks under appropriate storage conditions.
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Affiliation(s)
- F Marincs
- Plant Molecular Genetics Laboratory, Grasslands Research Centre, Palmerston North, New Zealand
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Purdy D, Park SF. Heterologous gene expression in Campylobacter coli: the use of bacterial luciferase in a promoter probe vector. FEMS Microbiol Lett 1993; 111:233-7. [PMID: 8405932 DOI: 10.1111/j.1574-6968.1993.tb06391.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
A novel promoter probe plasmid (pSP73) was constructed to allow the analysis of environmentally regulated gene expression in Campylobacter. The vector utilizes the luxAB genes from Xenorhabdus luminescens, which encode a thermostable luciferase, as reporters of gene expression. The utility of this reporter system was demonstrated by placing the expression of luxAB under the transcriptional control of the flaA gene promoter.
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Affiliation(s)
- D Purdy
- AFRC Institute of Food Research, Reading Laboratory, UK
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