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Zhu Y, Elcin E, Jiang M, Li B, Wang H, Zhang X, Wang Z. Use of whole-cell bioreporters to assess bioavailability of contaminants in aquatic systems. Front Chem 2022; 10:1018124. [PMID: 36247665 PMCID: PMC9561917 DOI: 10.3389/fchem.2022.1018124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Accepted: 09/14/2022] [Indexed: 11/13/2022] Open
Abstract
Water contamination has become increasingly a critical global environmental issue that threatens human and ecosystems’ health. Monitoring and risk assessment of toxic pollutants in water bodies is essential to identifying water pollution treatment needs. Compared with the traditional monitoring approaches, environmental biosensing via whole-cell bioreporters (WCBs) has exhibited excellent capabilities for detecting bioavailability of multiple pollutants by providing a fast, simple, versatile and economical way for environmental risk assessment. The performance of WCBs is determined by its elements of construction, such as host strain, regulatory and reporter genes, as well as experimental conditions. Previously, numerous studies have focused on the design and construction of WCB rather than improving the detection process and commercialization of this technology. For investigators working in the environmental field, WCB can be used to detect pollutants is more important than how they are constructed. This work provides a review of the development of WCBs and a brief introduction to genetic construction strategies and aims to summarize key studies on the application of WCB technology in detection of water contaminants, including organic pollutants and heavy metals. In addition, the current status of commercialization of WCBs is highlighted.
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Affiliation(s)
- Yi Zhu
- School of Environmental and Civil Engineering, Institute of Environmental Processes and Pollution Control, Jiangnan University, Wuxi, China
| | - Evrim Elcin
- Department of Agricultural Biotechnology, Division of Enzyme and Microbial Biotechnology, Faculty of Agriculture, Aydın Adnan Menderes University, Aydın, Turkey
| | - Mengyuan Jiang
- School of Environmental and Civil Engineering, Institute of Environmental Processes and Pollution Control, Jiangnan University, Wuxi, China
| | - Boling Li
- School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou, China
| | - Hailong Wang
- Biochar Engineering Technology Research Center of Guangdong Province, School of Environmental and Chemical Engineering, Foshan University, Foshan, China
| | - Xiaokai Zhang
- School of Environmental and Civil Engineering, Institute of Environmental Processes and Pollution Control, Jiangnan University, Wuxi, China
- *Correspondence: Xiaokai Zhang,
| | - Zhenyu Wang
- School of Environmental and Civil Engineering, Institute of Environmental Processes and Pollution Control, Jiangnan University, Wuxi, China
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2
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Dvořák P, Alvarez-Carreño C, Ciordia S, Paradela A, de Lorenzo V. An updated structural model of the A domain of the Pseudomonas putida XylR regulator poses an atypical interplay with aromatic effectors. Environ Microbiol 2021; 23:4418-4433. [PMID: 34097798 DOI: 10.1111/1462-2920.15628] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Revised: 05/16/2021] [Accepted: 06/06/2021] [Indexed: 01/14/2023]
Abstract
A revised model of the aromatic binding A domain of the σ54 -dependent regulator XylR of Pseudomonas putida mt-2 was produced based on the known 3D structures of homologous regulators PoxR, MopR and DmpR. The resulting frame was instrumental for mapping a number of mutations known to alter effector specificity, which were then reinterpreted under a dependable spatial reference. Some of these changes involved the predicted aromatic binding pocket but others occurred in distant locations, including dimerization interfaces and putative zinc binding site. The effector pocket was buried within the protein structure and accessible from the outside only through a narrow tunnel. Yet, several loop regions of the A domain could provide the flexibility required for widening such a tunnel for passage of aromatic ligands. The model was experimentally validated by treating the cells in vivo and the purified protein in vitro with benzyl bromide, which reacts with accessible nucleophilic residues on the protein surface. Structural and proteomic analyses confirmed the predicted in/out distribution of residues but also supported two additional possible scenarios of interaction of the A domain with aromatic effectors: a dynamic interaction of the fully structured yet flexible protein with the aromatic partner and/or inducer-assisted folding of the A domain.
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Affiliation(s)
- Pavel Dvořák
- Department of Experimental Biology (Section of Microbiology), Faculty of Science, Masaryk University, Brno, Kamenice 753/5, 62500, Czech Republic
| | - Carlos Alvarez-Carreño
- Systems Biology Department, Centro Nacional de Biotecnología-CSIC, Campus de Cantoblanco, Madrid, 28049, Spain.,Centro Tecnológico José Lladó, División de Desarrollo de Tecnologías Propias, Técnicas Reunidas, Calle Sierra Nevada, 16, San Fernando de Henares, Madrid, 28830, Spain
| | - Sergio Ciordia
- Proteomics Core Facilit, Centro Nacional de Biotecnología-CSIC, Campus de Cantoblanco, Madrid, 28049, Spain
| | - Alberto Paradela
- Proteomics Core Facilit, Centro Nacional de Biotecnología-CSIC, Campus de Cantoblanco, Madrid, 28049, Spain
| | - Víctor de Lorenzo
- Systems Biology Department, Centro Nacional de Biotecnología-CSIC, Campus de Cantoblanco, Madrid, 28049, Spain
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3
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Wang GH, Tsai TH, Kui CC, Cheng CY, Huang TL, Chung YC. Analysis of bioavailable toluene by using recombinant luminescent bacterial biosensors with different promoters. J Biol Eng 2021; 15:2. [PMID: 33407661 PMCID: PMC7789755 DOI: 10.1186/s13036-020-00254-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2020] [Accepted: 12/29/2020] [Indexed: 01/24/2023] Open
Abstract
In this study, we constructed recombinant luminescent Escherichia coli with T7, T3, and SP6 promoters inserted between tol and lux genes as toluene biosensors and evaluated their sensitivity, selectivity, and specificity for measuring bioavailable toluene in groundwater and river water. The luminescence intensity of each biosensor depended on temperature, incubation time, ionic strength, and concentrations of toluene and coexisting organic compounds. Toluene induced the highest luminescence intensity in recombinant lux-expressing E. coli with the T7 promoter [T7-lux-E. coli, limit of detection (LOD) = 0.05 μM], followed by that in E. coli with the T3 promoter (T3-lux-E. coli, LOD = 0.2 μM) and SP6 promoter (SP6-lux-E. coli, LOD = 0.5 μM). Luminescence may have been synergistically or antagonistically affected by coexisting organic compounds other than toluene; nevertheless, low concentrations of benzoate and toluene analogs had no such effect. In reproducibility experiments, the biosensors had low relative standard deviation (4.3-5.8%). SP6-lux-E. coli demonstrated high adaptability to environmental interference. T7-lux-E. coli biosensor-with low LOD, wide measurement range (0.05-500 μM), and acceptable deviation (- 14.3 to 9.1%)-is an efficient toluene biosensor. This is the first study evaluating recombinant lux E. coli with different promoters for their potential application in toluene measurement in actual water bodies.
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Affiliation(s)
- Guey-Horng Wang
- Research Center of Natural Cosmeceuticals Engineering, Xiamen Medical College, Xiamen, 361008, China
| | - Teh-Hua Tsai
- Department of Chemical Engineering and Biotechnology, National Taipei University of Technology, Taipei, Taiwan
| | - Chun-Chi Kui
- Department of Biological Science and Technology, China University of Science and Technology, Taipei, 11581, Taiwan
| | - Chiu-Yu Cheng
- Department of Biological Science and Technology, China University of Science and Technology, Taipei, 11581, Taiwan
| | - Tzu-Ling Huang
- Department of Biological Science and Technology, China University of Science and Technology, Taipei, 11581, Taiwan
| | - Ying-Chien Chung
- Department of Biological Science and Technology, China University of Science and Technology, Taipei, 11581, Taiwan.
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4
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Li JW, Zhang XY, Wu H, Bai YP. Transcription Factor Engineering for High-Throughput Strain Evolution and Organic Acid Bioproduction: A Review. Front Bioeng Biotechnol 2020; 8:98. [PMID: 32140463 PMCID: PMC7042172 DOI: 10.3389/fbioe.2020.00098] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Accepted: 02/03/2020] [Indexed: 01/15/2023] Open
Abstract
Metabolic regulation of gene expression for the microbial production of fine chemicals, such as organic acids, is an important research topic in post-genomic metabolic engineering. In particular, the ability of transcription factors (TFs) to respond precisely in time and space to various small molecules, signals and stimuli from the internal and external environment is essential for metabolic pathway engineering and strain development. As a key component, TFs are used to construct many biosensors in vivo using synthetic biology methods, which can be used to monitor the concentration of intracellular metabolites in organic acid production that would otherwise remain “invisible” within the intracellular environment. TF-based biosensors also provide a high-throughput screening method for rapid strain evolution. Furthermore, TFs are important global regulators that control the expression levels of key enzymes in organic acid biosynthesis pathways, therefore determining the outcome of metabolic networks. Here we review recent advances in TF identification, engineering, and applications for metabolic engineering, with an emphasis on metabolite monitoring and high-throughput strain evolution for the organic acid bioproduction.
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Affiliation(s)
- Jia-Wei Li
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Xiao-Yan Zhang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Hui Wu
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Yun-Peng Bai
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
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5
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Alvarez-Gonzalez G, Dixon N. Genetically encoded biosensors for lignocellulose valorization. BIOTECHNOLOGY FOR BIOFUELS 2019; 12:246. [PMID: 31636705 PMCID: PMC6792243 DOI: 10.1186/s13068-019-1585-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Accepted: 10/05/2019] [Indexed: 05/07/2023]
Abstract
Modern society is hugely dependent on finite oil reserves for the supply of fuels and chemicals. Moving our dependence away from these unsustainable oil-based feedstocks to renewable ones is, therefore, a critical factor towards the development of a low carbon bioeconomy. Lignin derived from biomass feedstocks offers great potential as a renewable source of aromatic compounds if methods for its effective valorization can be developed. Synthetic biology and metabolic engineering offer the potential to synergistically enable the development of cell factories with novel biosynthetic routes to valuable chemicals from these sustainable sources. Pathway design and optimization is, however, a major bottleneck due to the lack of high-throughput methods capable of screening large libraries of genetic variants and the metabolic burden associated with bioproduction. Genetically encoded biosensors can provide a solution by transducing the target metabolite concentration into detectable signals to provide high-throughput phenotypic read-outs and allow dynamic pathway regulation. The development and application of biosensors in the discovery and engineering of efficient biocatalytic processes for the degradation, conversion, and valorization of lignin are paving the way towards a sustainable and economically viable biorefinery.
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Affiliation(s)
| | - Neil Dixon
- Manchester Institute of Biotechnology (MIB), The University of Manchester, Manchester, UK
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6
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Ray S, Panjikar S, Anand R. Design of Protein-Based Biosensors for Selective Detection of Benzene Groups of Pollutants. ACS Sens 2018; 3:1632-1638. [PMID: 30084640 DOI: 10.1021/acssensors.8b00190] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Benzene and its derivatives form a class of priority pollutants whose exposure poses grave risk to human health. Since benzene lacks active functional groups, devising specific sensors for its direct detection from a milieu of aromatics has remained a daunting task. Here, we report three engineered protein-based biosensors that exclusively and specifically detect benzene and its derivatives up to a detection limit of 0.3 ppm. Further, the biosensor design has been engineered to create templates that possess the ability to specifically discriminate between alkyl substituted benzene derivatives; such as toluene, m-xylene, and mesitylene. Interference tests with simulated wastewater samples reveal that the engineered biosensors can selectively detect a specific benzene compound in water samples containing a milieu of high concentrations of commonly occurring pollutants. This work demonstrates the potential of structure guided protein engineering as a competent strategy toward design of selective biosensors for direct detection of benzene group of pollutants from real time environmental samples.
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Affiliation(s)
- Shamayeeta Ray
- Department of Chemistry, Indian Institute of Technology Bombay, Mumbai 400076, Maharashtra India
| | - Santosh Panjikar
- Department of Biochemistry and Molecular Biology, Monash University, Victoria 3800, Australia
- Australian Synchrotron, Victoria 3168, Australia
| | - Ruchi Anand
- Department of Chemistry, Indian Institute of Technology Bombay, Mumbai 400076, Maharashtra India
- Wadhwani Research Center for Bioengineering, IIT Bombay, Mumbai 400076, India
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7
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Frazão CR, Maton V, François JM, Walther T. Development of a Metabolite Sensor for High-Throughput Detection of Aldehydes in Escherichia Coli. Front Bioeng Biotechnol 2018; 6:118. [PMID: 30191150 PMCID: PMC6115493 DOI: 10.3389/fbioe.2018.00118] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Accepted: 08/03/2018] [Indexed: 01/31/2023] Open
Abstract
We have developed a fluorescence-based metabolite sensor enabling in vivo detection of various aldehydes of biotechnological interest in Escherichia coli. YqhC is a transcriptional regulator that is known to be involved in the upregulation of the yqhD-dgkA operon in the presence of aldehydes. We took advantage of this property by constructing a bi-modular biosensor, in which a sensing module constitutively expresses yqhC while a reporter module drives the expression of the syfp2 reporter gene that is put under control of the yqhD promoter. The sensitivity of the sensor has been optimized by engineering the 5′-UTRs of both the sensing and the reporter modules resulting in a 70-fold gain of fluorescence in response to the model compound glycolaldehyde at 5 mM. The optimized sensor further responded to other aldehydes when supplemented to the cultivation medium at concentrations of 1–10 mM. We furthermore showed that this metabolite sensor was functional in vivo as it responded to the presence of glycoladehyde that is specifically produced upon induction of a synthetic xylulose-1-phosphate pathway expressed in E. coli. This bi-modular sensor can therefore be employed as an exquisite tool for FACS-based ultra-high-throughput screening of aldehyde (over) producing enzymes.
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Affiliation(s)
- Cláudio R Frazão
- LISBP, CNRS, INRA, INSA, Université de Toulouse, Toulouse, France
| | - Victor Maton
- LISBP, CNRS, INRA, INSA, Université de Toulouse, Toulouse, France
| | - Jean M François
- LISBP, CNRS, INRA, INSA, Université de Toulouse, Toulouse, France.,Toulouse White Biotechnology (TWB), Toulouse, France
| | - Thomas Walther
- LISBP, CNRS, INRA, INSA, Université de Toulouse, Toulouse, France
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8
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Abstract
Phenolic aromatic compounds are a major source of environmental pollution. Currently there are no in situ methods for specifically and selectively detecting these pollutants. Here, we exploit the nature's biosensory machinery by employing Acinetobacter calcoaceticus NCIB8250 protein, MopR, as a model system to develop biosensors for selective detection of a spectrum of these pollutants. The X-ray structure of the sensor domain of MopR was used as a scaffold for logic-based tunable biosensor design. By employing a combination of in silico structure guided approaches, mutagenesis and isothermal calorimetric studies, we were able to generate biosensor templates, that can selectively and specifically sense harmful compounds like chlorophenols, cresols, catechol, and xylenols. Furthermore, the ability of native protein to selectively sense phenol as the primary ligand was also enhanced. Overall, this methodology can be extended as a suitable framework for development of a series of exclusive biosensors for accurate and selective detection of aromatic pollutants from real time environmental samples.
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Affiliation(s)
- Shamayeeta Ray
- IITB-Monash Research Academy, Mumbai 400076, Maharashtra, India
| | - Santosh Panjikar
- Department
of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3800, Australia
- Australian Synchrotron, Clayton, Victoria 3168, Australia
| | - Ruchi Anand
- Department
of Chemistry, Indian Institute of Technology Bombay, Mumbai 400076, Maharashtra India
- Wadhwani
Research Center for Bioengineering, IIT Bombay, Mumbai 400076, India
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9
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Ray S, Gunzburg MJ, Wilce M, Panjikar S, Anand R. Structural Basis of Selective Aromatic Pollutant Sensing by the Effector Binding Domain of MopR, an NtrC Family Transcriptional Regulator. ACS Chem Biol 2016; 11:2357-65. [PMID: 27362503 DOI: 10.1021/acschembio.6b00020] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Phenol and its derivatives are common pollutants that are present in industrial discharge and are major xenobiotics that lead to water pollution. To monitor as well as improve water quality, attempts have been made in the past to engineer bacterial in vivo biosensors. However, due to the paucity of structural information, there is insufficiency in gauging the factors that lead to high sensitivity and selectivity, thereby impeding development. Here, we present the crystal structure of the sensor domain of MopR (MopR(AB)) from Acinetobacter calcoaceticus in complex with phenol and its derivatives to a maximum resolution of 2.5 Å. The structure reveals that the N-terminal residues 21-47 possess a unique fold, which are involved in stabilization of the biological dimer, and the central ligand binding domain belongs to the "nitric oxide signaling and golgi transport" fold, commonly present in eukaryotic proteins that bind long-chain fatty acids. In addition, MopR(AB) nests a zinc atom within a novel zinc binding motif, crucial for maintaining structural integrity. We propose that this motif is crucial for orchestrated motions associated with the formation of the effector binding pocket. Our studies reveal that residues W134 and H106 play an important role in ligand binding and are the key selectivity determinants. Furthermore, comparative analysis of MopR with XylR and DmpR sensor domains enabled the design of a MopR binding pocket that is competent in binding DmpR-specific ligands. Collectively, these findings pave way towards development of specific/broad based biosensors, which can act as useful tools for detection of this class of pollutants.
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Affiliation(s)
- Shamayeeta Ray
- IITB-Monash Research Academy, Mumbai 400076, Maharashtra, India
| | - Menachem J. Gunzburg
- Department
of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3800, Australia
| | - Matthew Wilce
- Department
of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3800, Australia
| | - Santosh Panjikar
- Department
of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3800, Australia
- Australian Synchrotron, Clayton, Victoria 3168, Australia
| | - Ruchi Anand
- Department
of Chemistry, Indian Institute of Technology Bombay, Mumbai 400076, Maharashtra, India
- Wadhwani
Research Center for Bioengineering, IIT Bombay, Mumbai 400076, India
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10
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Fernandez-López R, Ruiz R, de la Cruz F, Moncalián G. Transcription factor-based biosensors enlightened by the analyte. Front Microbiol 2015; 6:648. [PMID: 26191047 PMCID: PMC4486848 DOI: 10.3389/fmicb.2015.00648] [Citation(s) in RCA: 88] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2015] [Accepted: 06/15/2015] [Indexed: 01/17/2023] Open
Abstract
Whole cell biosensors (WCBs) have multiple applications for environmental monitoring, detecting a wide range of pollutants. WCBs depend critically on the sensitivity and specificity of the transcription factor (TF) used to detect the analyte. We describe the mechanism of regulation and the structural and biochemical properties of TF families that are used, or could be used, for the development of environmental WCBs. Focusing on the chemical nature of the analyte, we review TFs that respond to aromatic compounds (XylS-AraC, XylR-NtrC, and LysR), metal ions (MerR, ArsR, DtxR, Fur, and NikR) or antibiotics (TetR and MarR). Analyzing the structural domains involved in DNA recognition, we highlight the similitudes in the DNA binding domains (DBDs) of these TF families. Opposite to DBDs, the wide range of analytes detected by TFs results in a diversity of structures at the effector binding domain. The modular architecture of TFs opens the possibility of engineering TFs with hybrid DNA and effector specificities. Yet, the lack of a crisp correlation between structural domains and specific functions makes this a challenging task.
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Affiliation(s)
| | | | | | - Gabriel Moncalián
- Departamento de Biología Molecular and Instituto de Biomedicina y Biotecnología de Cantabria, Universidad de Cantabria – Consejo Superior de Investigaciones CientíficasSantander, Spain
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11
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Shin HJ, Lim WK. Comparative evaluation of an electrochemical bioreporter for detecting phenolic compounds. Prep Biochem Biotechnol 2014; 46:71-7. [DOI: 10.1080/10826068.2014.979207] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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12
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Lacal J, Reyes-Darias JA, García-Fontana C, Ramos JL, Krell T. Tactic responses to pollutants and their potential to increase biodegradation efficiency. J Appl Microbiol 2012; 114:923-33. [PMID: 23163356 DOI: 10.1111/jam.12076] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2012] [Revised: 11/07/2012] [Accepted: 11/11/2012] [Indexed: 11/26/2022]
Abstract
A significant number of bacterial strains are able to use toxic aromatic hydrocarbons as carbon and energy sources. In a number of cases, the evolution of the corresponding degradation pathway was accompanied by the evolution of tactic behaviours either towards or away from these toxic carbon sources. Reports are reviewed which show that a chemoattraction to heterogeneously distributed aromatic pollutants increases the bioavailability of these compounds and their biodegradation efficiency. An extreme form of chemoattraction towards aromatic pollutants, termed 'hyperchemotaxis', was described for Pseudomonas putida DOT-T1E, which is based on the action of the plasmid-encoded McpT chemoreceptor. Cells with this phenotype were found of being able to approach and of establishing contact with undiluted crude oil samples. Although close McpT homologues are found on other degradation plasmids, the sequence of their ligand-binding domains does not share significant similarity with that of NahY, the other characterized chemoreceptor for aromatic hydrocarbons. This may suggest the existence of at least two families of chemoreceptors for aromatic pollutants. The use of receptor chimers comprising the ligand-binding region of McpT for biosensing purposes is discussed.
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Affiliation(s)
- J Lacal
- Department of Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, Granada, Spain
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13
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Shin HJ. Agarose-gel-immobilized recombinant bacterial biosensors for simple and disposable on-site detection of phenolic compounds. Appl Microbiol Biotechnol 2011; 93:1895-904. [DOI: 10.1007/s00253-011-3700-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2011] [Revised: 10/19/2011] [Accepted: 11/01/2011] [Indexed: 10/15/2022]
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14
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Yu Q, Li Y, Ma A, Liu W, Wang H, Zhuang G. An efficient design strategy for a whole-cell biosensor based on engineered ribosome binding sequences. Anal Bioanal Chem 2011; 401:2891-8. [PMID: 21947012 DOI: 10.1007/s00216-011-5411-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2011] [Revised: 08/16/2011] [Accepted: 09/06/2011] [Indexed: 10/17/2022]
Abstract
In prokaryotes, the ribosome binding sequence (RBS), located in the 5' untranslated region (5' UTR) of an mRNA, plays a critical role in enhancing mRNA translation and stability. To evaluate the effect of the RBS on the sensitivity and signal intensity of an environmental whole-cell biosensor, three Escherichia coli-based biosensors that respond to benzene, toluene, ethylbenzene, and the xylenes (BTEX) were constructed; the three biosensors have the same Pu promoter and xylR regulator from the Pseudomonas putida TOL plasmid but differ in the engineered RBS in their reporter genes. The results from time and dose-dependent induction of luminescence activity by 2-chlorotoluene showed that the BTEX-SE and BTEX-SD biosensors with engineered RBS had signal intensities approximately 10-35 times higher than the primary BTEX-W biosensor. The limits of detection (LOD) of the BTEX-SE and BTEX-SD biosensors were also significantly lower than the LOD of the BTEX-W biosensor (20 ± 5 μmol L(-1) and 25 ± 5 μmol L(-1) vs. 120 ± 10 μmol L(-1)). Moreover, the BTEX-SE and BTEX-SD biosensors responded three times more rapidly to the analytes. These results suggest that rationally designed RBS in the 5' UTR of a reporter gene may be a promising strategy for increasing the sensitivity, signal intensity, and response speed of whole-cell biosensors.
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Affiliation(s)
- Qing Yu
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, China
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15
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Di Gennaro P, Bruzzese N, Anderlini D, Aiossa M, Papacchini M, Campanella L, Bestetti G. Development of microbial engineered whole-cell systems for environmental benzene determination. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2011; 74:542-549. [PMID: 20980054 DOI: 10.1016/j.ecoenv.2010.08.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2009] [Revised: 07/29/2010] [Accepted: 08/01/2010] [Indexed: 05/30/2023]
Abstract
This paper reports the development of two recombinant bacterial systems that can be used to monitor environmental benzene contamination based on Escherichia coli, which carry genes coding for benzene dioxygenase and benzene dihydrodiol dehydrogenase from Pseudomonas putida MST. E. coli strains express these two enzymes under the control of the Ptac promoter or without any induction. These activities can be detected electrochemically or colorimetrically and used to monitor benzene pollution in environmental air samples collected from an oil refinery assessing benzene by different laboratory experimental procedures. The procedures involving whole-cell bioassays determine the concentration of benzene through benzene dioxygenase activity, which allows for direct correlation of oxygen consumption, and through the benzene dihydrodiol dehydrogenase that causes catechol accumulation and restores NADH necessary for the activity of the first enzyme. Oxygen consumption and catechol production deriving from both enzymatic activities are related to benzene concentration and their measurements determined the sensitivity of the system. The results indicated that the sensitivity was enough to detect the benzene vapor at a lower concentration level of 0.01 mM in about 30 min. The possibility for on-line monitoring of benzene concentration by our new recombinant cells results from the fact that no particular treatment of environmental samples is required. This is a major advantage over other biosensors or assays. Moreover, the development of microbial cells that did not require any addition or effectors for the transcription of the specific enzymes, allowed these systems to be more versatile in automated environmental benzene monitoring.
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Affiliation(s)
- P Di Gennaro
- Dept. Environmental Sciences, University of Milano-Bicocca, P.zza della Scienza 1, 20126 Milan, Italy
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16
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In situ detection of aromatic compounds with biosensor Pseudomonas putida cells preserved and delivered to soil in water-soluble gelatin capsules. Anal Bioanal Chem 2010; 400:1093-104. [DOI: 10.1007/s00216-010-4558-y] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2010] [Revised: 11/21/2010] [Accepted: 12/01/2010] [Indexed: 10/18/2022]
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17
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18
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Shin HJ. Genetically engineered microbial biosensors for in situ monitoring of environmental pollution. Appl Microbiol Biotechnol 2010; 89:867-77. [DOI: 10.1007/s00253-010-2990-8] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2010] [Revised: 10/27/2010] [Accepted: 10/27/2010] [Indexed: 10/18/2022]
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19
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Zhong Z, Fritzsche M, Pieper SB, Wood TK, Lear KL, Dandy DS, Reardon KF. Fiber optic monooxygenase biosensor for toluene concentration measurement in aqueous samples. Biosens Bioelectron 2010; 26:2407-12. [PMID: 21081273 DOI: 10.1016/j.bios.2010.10.021] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2010] [Revised: 10/07/2010] [Accepted: 10/11/2010] [Indexed: 11/19/2022]
Abstract
Measurements of pollutants such as toluene are critical for the characterization of contaminated sites and for the monitoring of remediation processes and wastewater treatment effluents. Fiber optic enzymatic biosensors have the potential to provide cost-effective, real time, continuous, in situ measurements. In this study, a fiber optic enzymatic biosensor was constructed and characterized for the measurement of toluene concentrations in aqueous solutions. The biological recognition element was toluene ortho-monooxygenase (TOM), expressed by Escherichia coli TG1 carrying pBS(Kan)TOM, while an optical fiber coated with an oxygen-sensitive ruthenium-based phosphorescent dye served as the transducer. Toluene was detected based on the enzymatic reaction catalyzed by TOM, which resulted in the consumption of oxygen and changes in the phosphorescence intensity. The biosensor was found to have a limit of detection of 3 μM, a linear signal range up to 100 μM, and a response time of 1 h. The performance was reproducible with different biosensors (RSD=7.4%, n=8). The biosensor activity declined with each measurement and with storage time, particularly at elevated temperatures. This activity loss could be partially reversed by exposure to formate, suggesting that NADH consumption was the primary factor limiting lifetime. This is the first report of an enzymatic toluene sensor and of an oxygenase-based biosensor. Since many oxygenases have been reported, the design concept of this oxygenase-based biosensor has the potential to broaden biosensor applications in environmental monitoring.
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Affiliation(s)
- Zhong Zhong
- Department of Chemical and Biological Engineering, Colorado State University, Fort Collins, CO 80523, USA
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20
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Construction and characterization of Escherichia coli whole-cell biosensors for toluene and related compounds. Curr Microbiol 2010; 62:690-6. [PMID: 20872219 DOI: 10.1007/s00284-010-9764-5] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2010] [Accepted: 09/03/2010] [Indexed: 10/19/2022]
Abstract
The XylR regulatory protein is a transcriptional activator from the TOL plasmid of Pseudomonas putida mt-2 that is involved in the toluene and benzene degradation pathway. Here we describe the construction and laboratory characterization of recombinant biosensors (pGLPX plasmids) based on XylR and its cognate promoter (Pu). In the pGLPX plasmid, the reporter luc gene is under the control of the Pu promoter. We evaluated the ability of two distinct nucleotide sequences to function as SD elements and improve sensitivity of bioreporting. We also evaluated the effect of introducing the T₂rrnβ terminator on the specificity of the construct. E. coli transformed with pGLPX plasmids were used to sense toluene and its derivatives. The pattern of induction was different for each derivative. In general, more luciferase activity was induced by toluene and benzene than by TNT and DNT at most tested concentrations. The bioluminescence response of the reporter strains to the nitrotoluenes was significantly stronger at lower concentrations (≥ 50 μmol) than at higher concentrations. Our results show that the SD sequence (taaggagg) is crucially important for biosensor sensitivity. The presence of the T₂rrnβ terminator in the bioreporter plasmid prevents nonspecific responses and also reduces biosensor sensitivity upon exposure to inducers. These data suggest that pGLPX strains can be used as whole-cell biosensors to detect toluene and related compounds. Further investigation will be required to optimize the application of pGLPX biosensors.
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21
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Escherichia coli as a bioreporter in ecotoxicology. Appl Microbiol Biotechnol 2010; 88:1007-25. [PMID: 20803141 DOI: 10.1007/s00253-010-2826-6] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2010] [Revised: 08/02/2010] [Accepted: 08/03/2010] [Indexed: 01/30/2023]
Abstract
Ecotoxicological assessment relies to a large extent on the information gathered with surrogate species and the extrapolation of test results across species and different levels of biological organisation. Bacteria have long been used as a bioreporter for genotoxic testing and general toxicity. Today, it is clear that bacteria have the potential for screening of other toxicological endpoints. Escherichia coli has been studied for years; in-depth knowledge of its biochemistry and genetics makes it the most proficient prokaryote for the development of new toxicological assays. Several assays have been designed with E. coli as a bioreporter, and the recent trend to develop novel, better advanced reporters makes bioreporter development one of the most dynamic in ecotoxicology. Based on in-depth knowledge of E. coli, new assays are being developed or existing ones redesigned, thanks to the availability of new reporter genes and new or improved substrates. The technological evolution towards easier and more sensitive detection of different gene products is another important aspect. Often, this requires the redesign of the bacterium to make it compatible with the novel measuring tests. Recent advances in surface chemistry and nanoelectronics open the perspective for advanced reporter based on novel measuring platforms and with an online potential. In this article, we will discuss the use of E. coli-based bioreporters in ecotoxicological applications as well as some innovative sensors awaited for the future.
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22
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Dietrich JA, McKee AE, Keasling JD. High-throughput metabolic engineering: advances in small-molecule screening and selection. Annu Rev Biochem 2010; 79:563-90. [PMID: 20367033 DOI: 10.1146/annurev-biochem-062608-095938] [Citation(s) in RCA: 245] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Metabolic engineering for the overproduction of high-value small molecules is dependent upon techniques in directed evolution to improve production titers. The majority of small molecules targeted for overproduction are inconspicuous and cannot be readily obtained by screening. We provide a review on the development of high-throughput colorimetric, fluorescent, and growth-coupled screening techniques, enabling inconspicuous small-molecule detection. We first outline constraints on throughput imposed during the standard directed evolution workflow (library construction, transformation, and screening) and establish a screening and selection ladder on the basis of small-molecule assay throughput and sensitivity. An in-depth analysis of demonstrated screening and selection approaches for small-molecule detection is provided. Particular focus is placed on in vivo biosensor-based detection methods that reduce or eliminate in vitro assay manipulations and increase throughput. We conclude by providing our prospectus for the future, focusing on transcription factor-based detection systems as a natural microbial mode of small-molecule detection.
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Affiliation(s)
- Jeffrey A Dietrich
- UCSF-UCB Joint Graduate Group in Bioengineering, Berkeley, California 94720, USA.
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23
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Weber W, Luzi S, Karlsson M, Fussenegger M. A novel hybrid dual-channel catalytic-biological sensor system for assessment of fruit quality. J Biotechnol 2009; 139:314-7. [DOI: 10.1016/j.jbiotec.2009.01.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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24
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A novel E. coli biosensor for detecting aromatic aldehydes based on a responsive inducible archaeal promoter fused to the green fluorescent protein. Appl Microbiol Biotechnol 2009; 82:67-77. [DOI: 10.1007/s00253-008-1771-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2008] [Revised: 10/23/2008] [Accepted: 10/25/2008] [Indexed: 10/21/2022]
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25
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Broad-host-range expression vectors with tightly regulated promoters and their use to examine the influence of TraR and TraM expression on Ti plasmid quorum sensing. Appl Environ Microbiol 2008; 74:5053-62. [PMID: 18606801 DOI: 10.1128/aem.01098-08] [Citation(s) in RCA: 250] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Experiments requiring strong repression and precise control of cloned genes can be difficult to conduct because of the relatively high basal level of expression of currently employed promoters. We report the construction of a family of vectors that contain a reengineered lacI(q)-lac promoter-operator complex in which cloned genes are strongly repressed in the absence of inducer. The vectors, all based on the broad-host-range plasmid pBBR1, are mobilizable and stably replicate at moderate copy number in representatives of the alpha- and gammaproteobacteria. Each vector contains a versatile multiple cloning site that includes an NdeI site allowing fusion of the cloned gene to the initiation codon of lacZalpha. In each tested bacterium, a uidA reporter fused to the promoter was not expressed at a detectable level in the absence of induction but was inducible by 10- to 100-fold, depending on the bacterium. The degree of induction was controllable by varying the concentration of inducer. When the vector was tested in Agrobacterium tumefaciens, a cloned copy of the traR gene, the product of which is needed at only a few copies per cell, did not confer activity under noninducing conditions. We used this attribute of very tight and variably regulatable control to assess the relative amounts of TraR required to activate the Ti plasmid conjugative transfer system. We identified levels of induction that gave wild-type transfer frequencies, as well as levels that induced correspondingly lower frequencies of transfer. We also used this system to show that the antiactivator TraM sets the level of intracellular TraR required for tra gene activation.
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26
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Li YF, Li FY, Ho CL, Liao VHC. Construction and comparison of fluorescence and bioluminescence bacterial biosensors for the detection of bioavailable toluene and related compounds. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2008; 152:123-9. [PMID: 17583401 DOI: 10.1016/j.envpol.2007.05.002] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2007] [Revised: 04/16/2007] [Accepted: 05/03/2007] [Indexed: 05/15/2023]
Abstract
Environmental pollution with petroleum products such as benzene, toluene, ethylbenzene, and xylenes (BTEX) has garnered increasing awareness because of its serious consequences for human health and the environment. We have constructed toluene bacterial biosensors comprised of two reporter genes, gfp and luxCDABE, characterized by green fluorescence and luminescence, respectively, and compared their abilities to detect bioavailable toluene and related compounds. The bacterial luminescence biosensor allowed faster and more-sensitive detection of toluene; the fluorescence biosensor strain was much more stable and thus more applicable for long-term exposure. Both luminescence and fluorescence biosensors were field-tested to measure the relative bioavailability of BTEX in contaminated groundwater and soil samples. The estimated BTEX concentrations determined by the luminescence and fluorescence bacterial biosensors were closely comparable to each other. Our results demonstrate that both bacterial luminescence and fluorescence biosensors are useful in determining the presence and the bioavailable fractions of BTEX in the environment.
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Affiliation(s)
- Yueh-Fen Li
- Department of Bioenvironmental Systems Engineering, National Taiwan University, 1 Roosevelt Road, Sec. 4, Taipei 106, Taiwan
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27
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Tizzard AC, Bergsma JH, Lloyd-Jones G. A resazurin-based biosensor for organic pollutants. Biosens Bioelectron 2006; 22:759-63. [PMID: 16487702 DOI: 10.1016/j.bios.2006.01.011] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2005] [Revised: 12/20/2005] [Accepted: 01/09/2006] [Indexed: 12/01/2022]
Abstract
A new rapid biosensor method employing the dye resazurin as an indicator of bacterial respiration has been developed to provide a rapid, facile and specific biosensor for environmental contaminants that does not rely on genetic modification techniques, is suitable for a high-throughput multiwell format, and is ideally suited to resource-constrained environmental monitoring situations. This whole-cell biosensor has been applied to the test analyte toluene using natural toluene-degrading bacteria as the biological component and is competitive with more complex recombinant approaches. The redox-driven biosensor is dependent on the catabolism of a specific compound, concomitantly reducing the redox indicator resazurin to provide the analytical signal in a whole-cell biosensor assay.
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Affiliation(s)
- Aynsley C Tizzard
- Lincoln Ventures, Lincoln University, PO Box 133, Lincoln 8152, New Zealand
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28
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Michelini E, Guardigli M, Magliulo M, Mirasoli M, Roda A, Simoni P, Baraldini M. Bioluminescent Biosensors Based on Genetically Engineered Living Cells in Environmental and Food Analysis. ANAL LETT 2006. [DOI: 10.1080/00032710600713156] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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29
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Galvão TC, de Lorenzo V. Transcriptional regulators à la carte: engineering new effector specificities in bacterial regulatory proteins. Curr Opin Biotechnol 2006; 17:34-42. [PMID: 16359854 DOI: 10.1016/j.copbio.2005.12.002] [Citation(s) in RCA: 90] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2005] [Revised: 11/15/2005] [Accepted: 12/05/2005] [Indexed: 11/27/2022]
Abstract
For many regulators of bacterial biodegradation pathways, small molecule/effector binding is the signal for triggering transcriptional activation. Thus, regulation results from a cross-talk between chemicals sensed by transcriptional factors and operon expression status. These features can be utilised in the construction of biosensors for a wide range of target compounds as, in principle, any regulatory protein whose activity is modulated by binding to a small molecule can have its effector/inducer profile artificially altered. The cognate specificities of a number of regulatory proteins have been modified as an astute approach to developing, among others, bacterial biosensors for environmentally relevant compounds.
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Affiliation(s)
- Teca Calcagno Galvão
- Department of Microbial Biotechnology, Centro Nacional de Biotecnología-CSIC, Madrid 28049, Spain.
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30
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Shin HJ, Park HH, Lim WK. Freeze-dried recombinant bacteria for on-site detection of phenolic compounds by color change. J Biotechnol 2005; 119:36-43. [PMID: 16051389 DOI: 10.1016/j.jbiotec.2005.06.002] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2004] [Revised: 05/24/2005] [Accepted: 06/01/2005] [Indexed: 11/16/2022]
Abstract
We herein report the development of a recombinant bacterial biosensor for the rapid and easy detection of phenolic compounds in the field. A plasmid was designed to encode a beta-galactosidase reporter gene under the control of capR, an activator involved in phenolic compound degradation. The construct was transformed into Escherichia coli, and transformed cells were stored after being freeze-dried in the presence of sucrose. For detection of phenolic compounds, the cells were rehydrated, and used instantly, without any growth step. In the presence of 0.1 microM-10mM phenol, we observed a red color from hydrolysis of chlorophenol red beta-D-galactopyranoside (CPRG) or an indigo color from hydrolysis of X-galactopyranoside (X-gal). Other phenolic compounds could be detected by this system, including catechol, 2-methylphenol, 2-chlorophenol, 3-methylphenol, 2-nitrophenol, and 4-chlorophenol. These results suggest that this novel bacteria biosensor may be useful for easy, on-site detection of phenolic compounds without the need for unwieldy equipment or sample pretreatment. Indeed, biosensor systems involving beta-galactosidase-expressing freeze-dried recombinant bacteria could prove useful for the in situ detection of many more compounds in the future.
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Affiliation(s)
- Hae Ja Shin
- Environmental Engineering Major, Division of Applied Bioengineering, Dongseo University, Busan 617-716, Republic of Korea.
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31
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Park HH, Lim WK, Shin HJ. In vitro binding of purified NahR regulatory protein with promoter Psal. Biochim Biophys Acta Gen Subj 2005; 1725:247-55. [PMID: 15978733 DOI: 10.1016/j.bbagen.2005.05.015] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2005] [Revised: 04/26/2005] [Accepted: 05/10/2005] [Indexed: 11/17/2022]
Abstract
The NahR regulatory protein activates the naphthalene catabolic operon through binding to the Psal promoter in the presence of salicylate. Here, we investigated in vitro binding interaction between NahR and Psal using purified functional recombinant NahR. The T7-tagged NahR was shown to exist as a monomer in solution. Electrophoretic mobility shift assay (EMSA) showed that purified NahR bound to Psal in 3 different forms, whereas surface plasmon resonance (SPR) showed on an SPR chip at ratios ranging from 1:1 (at 0.42 microM NahR) to 8:1 (at 6.8 microM NahR). The binding was slightly inhibited by salicylate, suggesting that salicylate may not be involved in the binding of NahR to the promoter, but rather may be important in the activation of prebound NahR. An examination of the binding kinetics by SPR for the interaction between NahR and Psal revealed that the equilibrium dissociation constant was approximately 2.44 x 10(-6) M and the association and dissociation rates were 7.82 x 10(4) M(-1) s(-1) and 0.191 s(-1), respectively. These results demonstrate for the first time that purified NahR binds as a monomer to Psal and undergoes multimerization. In addition, we present novel data on the kinetics of NahR binding.
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Affiliation(s)
- Hoo Hwi Park
- Department of Molecular Biology, College of Natural Sciences, Pusan National University, Busan, 609-735, Republic of Korea
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