1
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Gines G, Espada R, Dramé-Maigné A, Baccouche A, Larrouy N, Rondelez Y. Functional analysis of single enzymes combining programmable molecular circuits with droplet-based microfluidics. NATURE NANOTECHNOLOGY 2024; 19:800-809. [PMID: 38409552 DOI: 10.1038/s41565-024-01617-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Accepted: 01/22/2024] [Indexed: 02/28/2024]
Abstract
The analysis of proteins at the single-molecule level reveals heterogeneous behaviours that are masked in ensemble-averaged techniques. The digital quantification of enzymes traditionally involves the observation and counting of single molecules partitioned into microcompartments via the conversion of a profluorescent substrate. This strategy, based on linear signal amplification, is limited to a few enzymes with sufficiently high turnover rate. Here we show that combining the sensitivity of an exponential molecular amplifier with the modularity of DNA-enzyme circuits and droplet readout makes it possible to specifically detect, at the single-molecule level, virtually any D(R)NA-related enzymatic activity. This strategy, denoted digital PUMA (Programmable Ultrasensitive Molecular Amplifier), is validated for more than a dozen different enzymes, including many with slow catalytic rate, and down to the extreme limit of apparent single turnover for Streptococcus pyogenes Cas9. Digital counting uniquely yields absolute molar quantification and reveals a large fraction of inactive catalysts in all tested commercial preparations. By monitoring the amplification reaction from single enzyme molecules in real time, we also extract the distribution of activity among the catalyst population, revealing alternative inactivation pathways under various stresses. Our approach dramatically expands the number of enzymes that can benefit from quantification and functional analysis at single-molecule resolution. We anticipate digital PUMA will serve as a versatile framework for accurate enzyme quantification in diagnosis or biotechnological applications. These digital assays may also be utilized to study the origin of protein functional heterogeneity.
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Affiliation(s)
- Guillaume Gines
- Laboratoire Gulliver, UMR7083 CNRS/ESPCI Paris-PSL Research University, Paris, France.
| | - Rocίo Espada
- Laboratoire Gulliver, UMR7083 CNRS/ESPCI Paris-PSL Research University, Paris, France
| | - Adèle Dramé-Maigné
- Laboratoire Gulliver, UMR7083 CNRS/ESPCI Paris-PSL Research University, Paris, France
| | - Alexandre Baccouche
- LIMMS, IRL 2820 CNRS-Institute of Industrial Science, The University of Tokyo, Tokyo, Japan
| | - Nicolas Larrouy
- Laboratoire Gulliver, UMR7083 CNRS/ESPCI Paris-PSL Research University, Paris, France
| | - Yannick Rondelez
- Laboratoire Gulliver, UMR7083 CNRS/ESPCI Paris-PSL Research University, Paris, France
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2
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Ando J, Murai K, Mori M, Michiyuki T, Iida T, Makino A, Shinoda H, Watanabe R. Exploring fluoropolymers for fabrication of femtoliter chamber arrays used in digital bioanalysis. Sci Rep 2024; 14:11442. [PMID: 38769440 PMCID: PMC11106263 DOI: 10.1038/s41598-024-61726-8] [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: 12/02/2023] [Accepted: 05/08/2024] [Indexed: 05/22/2024] Open
Abstract
The global supply of fluoropolymers and fluorinated solvents is decreasing due to environmental concerns regarding polyfluoroalkyl substances. CYTOP has been used for decades primarily as a component of a femtoliter chamber array for digital bioanalysis; however, its supply has recently become scarce, increasing the urgency of fabricating a femtoliter chamber array using alternative materials. In this study, we investigated the feasibility of fabricating a femtoliter chamber array using four types of fluoropolymers in stable supply as candidate substitutes and verified their applicability for digital bioanalysis. Among these candidates, Fluorine Sealant emerged as a viable option for fabricating femtoliter chamber arrays using a conventional photolithography process. To validate its efficacy, we performed various digital bioanalysis using FP-A-based chamber arrays with model enzymes such as CRISPR-Cas, horseradish peroxidase, and β-galactosidase. The results demonstrated the similar performance to that of CYTOP, highlighting the broader utility of FP-A in digital bioanalysis. Our findings underscore the potential of FP-A to enhance the versatility of digital bioanalysis and foster the ongoing advancement of innovative diagnostic technologies.
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Affiliation(s)
- Jun Ando
- Molecular Physiology Laboratory, Cluster for Pioneering Research, RIKEN, Saitama, Japan.
| | - Kazue Murai
- Molecular Physiology Laboratory, Cluster for Pioneering Research, RIKEN, Saitama, Japan
| | - Makiko Mori
- Molecular Physiology Laboratory, Cluster for Pioneering Research, RIKEN, Saitama, Japan
| | - Tomoe Michiyuki
- Molecular Physiology Laboratory, Cluster for Pioneering Research, RIKEN, Saitama, Japan
| | - Tatsuya Iida
- Molecular Physiology Laboratory, Cluster for Pioneering Research, RIKEN, Saitama, Japan
| | - Asami Makino
- Molecular Physiology Laboratory, Cluster for Pioneering Research, RIKEN, Saitama, Japan
| | - Hajime Shinoda
- Molecular Physiology Laboratory, Cluster for Pioneering Research, RIKEN, Saitama, Japan
| | - Rikiya Watanabe
- Molecular Physiology Laboratory, Cluster for Pioneering Research, RIKEN, Saitama, Japan.
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3
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Burden DL, Meyer JJ, Michael RD, Anderson SC, Burden HM, Peña SM, Leong-Fern KJ, Van Ye LA, Meyer EC, Keranen-Burden LM. Confirming Silent Translocation through Nanopores with Simultaneous Single-Molecule Fluorescence and Single-Channel Electrical Recordings. Anal Chem 2023; 95:18020-18028. [PMID: 37991877 PMCID: PMC10719886 DOI: 10.1021/acs.analchem.3c02329] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Revised: 11/07/2023] [Accepted: 11/08/2023] [Indexed: 11/24/2023]
Abstract
Most of what is known concerning the luminal passage of materials through nanopores arises from electrical measurements. Whether nanopores are biological, solid-state, synthetic, hybrid, glass-capillary-based, or protein ion channels in cells and tissues, characteristic signatures embedded in the flow of ionic current are foundational to understanding functional behavior. In contrast, this work describes passage through a nanopore that occurs without producing an electrical signature. We refer to the phenomenon as "silent translocation." By definition, silent translocations are invisible to the standard tools of electrophysiology and fundamentally require a simultaneous ancillary measurement technique for positive identification. As a result, this phenomenon has been largely unexplored in the literature. Here, we report on a derivative of Cyanine 5 (sCy5a) that passes through the α-hemolysin (αHL) nanopore silently. Simultaneously acquired single-molecule fluorescence and single-channel electrical recordings from bilayers formed over a closed microcavity demonstrate that translocation does indeed take place, albeit infrequently. We report observations of silent translocation as a function of time, dye concentration, and nanopore population in the bilayer. Lastly, measurement of the translocation rate as a function of applied potential permits estimation of an effective energy barrier for transport through the pore as well as the effective charge on the dye, all in the absence of an information-containing electrical signature.
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Affiliation(s)
- Daniel L. Burden
- Chemistry Department, Wheaton College, Wheaton, Illinois 60187, United States
| | - Joshua J. Meyer
- Chemistry Department, Wheaton College, Wheaton, Illinois 60187, United States
| | - Richard D. Michael
- Chemistry Department, Wheaton College, Wheaton, Illinois 60187, United States
| | - Sophie C. Anderson
- Chemistry Department, Wheaton College, Wheaton, Illinois 60187, United States
| | - Hannah M. Burden
- Chemistry Department, Wheaton College, Wheaton, Illinois 60187, United States
| | - Sophia M. Peña
- Chemistry Department, Wheaton College, Wheaton, Illinois 60187, United States
| | | | - Lily Anne Van Ye
- Chemistry Department, Wheaton College, Wheaton, Illinois 60187, United States
| | - Elizabeth C. Meyer
- Chemistry Department, Wheaton College, Wheaton, Illinois 60187, United States
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4
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Mimura H, Osaki T, Takamori S, Nakao K, Takeuchi S. Lipid Bilayer Reformation Using the Wiping Blade for Improved Ion Channel Analysis. Anal Chem 2023; 95:17354-17361. [PMID: 37968939 DOI: 10.1021/acs.analchem.3c03707] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2023]
Abstract
The measurement of ion permeation activity across planar lipid bilayers is a useful technique for the functional analysis and drug evaluation of ion channels at the single-molecule level. To enhance the data throughput, parallelization of lipid bilayers is desirable. However, existing parallelized approaches face challenges in simultaneously and efficiently measuring ion channel activities under various conditions on one chip. In this study, we propose an approach to overcome these limitations by developing a device capable of repeated measurements of ion channels incorporated into individually arrayed lipid bilayers. Our device forms an array of a lipid bilayer at a micropore on a separator by merging two lipid monolayers assembled on the surface of aqueous droplets. We introduce a vertically moving, blade-shaped module─referred to as a "wiping blade"─which enables controlled disruption and reformation of the bilayer at the micropore. By optimizing the surface properties and clearance of the wiping blade, we successfully achieved repeated bilayer formation. The arrayed lipid bilayer device with the integrated wiping blade module demonstrates a 5-fold improvement in data throughput during ion channel activity measurements. Finally, we validate the practical utility of our device by evaluating the effects of an ion channel inhibitor. The developed device opens new avenues for high-throughput analysis and screening of ion channels, leading to significant advancements in drug discovery and functional studies of membrane proteins. It offers a powerful tool for researchers in the field and holds promise for accelerating drug development by targeting ion channels.
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Affiliation(s)
- Hisatoshi Mimura
- Kanagawa Institute of Industrial Science and Technology, 3-2-1 Sakado, Takatsu-ku, Kawasaki, Kanagawa 213-0012, Japan
| | - Toshihisa Osaki
- Kanagawa Institute of Industrial Science and Technology, 3-2-1 Sakado, Takatsu-ku, Kawasaki, Kanagawa 213-0012, Japan
- MAQsys Inc., 3-2-1 Sakado, Takatsu-ku, Kawasaki, Kanagawa 213-0012, Japan
| | - Sho Takamori
- Kanagawa Institute of Industrial Science and Technology, 3-2-1 Sakado, Takatsu-ku, Kawasaki, Kanagawa 213-0012, Japan
| | - Kenji Nakao
- MAQsys Inc., 3-2-1 Sakado, Takatsu-ku, Kawasaki, Kanagawa 213-0012, Japan
| | - Shoji Takeuchi
- Kanagawa Institute of Industrial Science and Technology, 3-2-1 Sakado, Takatsu-ku, Kawasaki, Kanagawa 213-0012, Japan
- Graduate School of Information Science and Technology, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
- Institute of Industrial Science, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan
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5
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Ueno H, Sano M, Hara M, Noji H. Digital Cascade Assays for ADP- or ATP-Producing Enzymes Using a Femtoliter Reactor Array Device. ACS Sens 2023; 8:3400-3407. [PMID: 37590841 PMCID: PMC10521141 DOI: 10.1021/acssensors.3c00587] [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: 03/27/2023] [Accepted: 07/31/2023] [Indexed: 08/19/2023]
Abstract
Digital enzyme assays are emerging biosensing methods for highly sensitive quantitative analysis of biomolecules with single-molecule detection sensitivity. However, current digital enzyme assays require a fluorogenic substrate for detection, which limits the applicability of this method to certain enzymes. ATPases and kinases are representative enzymes for which fluorogenic substrates are not available; however, these enzymes form large domains and play a central role in biology. In this study, we implemented a fluorogenic cascade reaction in a femtoliter reactor array device to develop a digital bioassay platform for ATPases and kinases. The digital cascade assay enabled quantitative measurement of the single-molecule activity of F1-ATPase, the catalytic portion of ATP synthase. We also demonstrated a digital assay for human choline kinase α. Furthermore, we developed a digital cascade assay for ATP-synthesizing enzymes and demonstrated a digital assay for pyruvate kinase. These results show the high versatility of this assay platform. Thus, the digital cascade assay has great potential for the highly sensitive detection and accurate characterization of various ADP- and ATP-producing enzymes, such as kinases, which may serve as disease biomarkers.
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Affiliation(s)
| | - Mio Sano
- Department of Applied Chemistry,
Graduate School of Engineering, The University
of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
- Digital Bioanalysis Laboratory, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Mayu Hara
- Department of Applied Chemistry,
Graduate School of Engineering, The University
of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
- Digital Bioanalysis Laboratory, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
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6
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Kinosita Y, Sowa Y. Flagellar polymorphism-dependent bacterial swimming motility in a structured environment. Biophys Physicobiol 2023; 20:e200024. [PMID: 37867560 PMCID: PMC10587448 DOI: 10.2142/biophysico.bppb-v20.0024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Accepted: 05/29/2023] [Indexed: 10/24/2023] Open
Abstract
Most motile bacteria use supramolecular motility machinery called bacterial flagellum, which converts the chemical energy gained from ion flux into mechanical rotation. Bacterial cells sense their external environment through a two-component regulatory system consisting of a histidine kinase and response regulator. Combining these systems allows the cells to move toward favorable environments and away from their repellents. A representative example of flagellar motility is run-and-tumble swimming in Escherichia coli, where the counter-clockwise (CCW) rotation of a flagellar bundle propels the cell forward, and the clockwise (CW) rotation undergoes cell re-orientation (tumbling) upon switching the direction of flagellar motor rotation from CCW to CW. In this mini review, we focus on several types of chemotactic behaviors that respond to changes in flagellar shape and direction of rotation. Moreover, our single-cell analysis demonstrated back-and-forth swimming motility of an original E. coli strain. We propose that polymorphic flagellar changes are required to enhance bacterial movement in a structured environment as a colony spread on an agar plate.
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Affiliation(s)
| | - Yoshiyuki Sowa
- Department of Frontier Bioscience, Hosei University, Tokyo 184-8584, Japan
- Research Center for Micro-Nano Technology, Hosei University, Tokyo 184-8584, Japan
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7
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Montalbo RCK, Tu HL. Micropatterning of functional lipid bilayer assays for quantitative bioanalysis. BIOMICROFLUIDICS 2023; 17:031302. [PMID: 37179590 PMCID: PMC10171888 DOI: 10.1063/5.0145997] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Accepted: 04/24/2023] [Indexed: 05/15/2023]
Abstract
Interactions of the cell with its environment are mediated by the cell membrane and membrane-localized molecules. Supported lipid bilayers have enabled the recapitulation of the basic properties of cell membranes and have been broadly used to further our understanding of cellular behavior. Coupled with micropatterning techniques, lipid bilayer platforms have allowed for high throughput assays capable of performing quantitative analysis at a high spatiotemporal resolution. Here, an overview of the current methods of the lipid membrane patterning is presented. The fabrication and pattern characteristics are briefly described to present an idea of the quality and notable features of the methods, their utilizations for quantitative bioanalysis, as well as to highlight possible directions for the advanced micropatterning lipid membrane assays.
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8
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Iida T, Ando J, Shinoda H, Makino A, Yoshimura M, Murai K, Mori M, Takeuchi H, Noda T, Nishimasu H, Watanabe R. Compact wide-field femtoliter-chamber imaging system for high-speed and accurate digital bioanalysis. LAB ON A CHIP 2023; 23:684-691. [PMID: 36255223 DOI: 10.1039/d2lc00741j] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
The femtoliter-chamber array is a bioanalytical platform that enables highly sensitive and quantitative analysis of biological reactions at the single-molecule level. This feature has been considered a key technology for "digital bioanalysis" in the biomedical field; however, its versatility is limited by the need for a large and expensive setup such as a fluorescence microscope, which requires a long time to acquire the entire image of a femtoliter-chamber array. To address these issues, we developed a compact and inexpensive wide-field imaging system (COWFISH) that can acquire fluorescence images with a large field of view (11.8 mm × 7.9 mm) and a high spatial resolution of ∼ 3 μm, enabling high-speed analysis of sub-million femtoliter chambers in 20 s. Using COWFISH, we demonstrated a CRISPR-Cas13a-based digital detection of viral RNA of SARS-CoV-2 with an equivalent detection sensitivity (limit of detection: 480 aM) and a 10-fold reduction in total imaging time, as compared to confocal fluorescence microscopy. In addition, we demonstrated the feasibility of COWFISH to discriminate between SARS-CoV-2-positive and -negative clinical specimens with 95% accuracy, showing its application in COVID-19 diagnosis. Therefore, COWFISH can serve as a compact and inexpensive imaging system for high-speed and accurate digital bioanalysis, paving a way for various biomedical applications, such as diagnosis of viral infections.
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Affiliation(s)
| | - Jun Ando
- Cluster for Pioneering Research, RIKEN, Japan.
| | | | | | | | - Kazue Murai
- Cluster for Pioneering Research, RIKEN, Japan.
| | - Makiko Mori
- Cluster for Pioneering Research, RIKEN, Japan.
| | - Hiroaki Takeuchi
- Department of Molecular Virology, Tokyo Medical and Dental University, Japan
| | - Takeshi Noda
- Institute for Life and Medical Sciences, Kyoto University, Japan
| | - Hiroshi Nishimasu
- Department of Chemistry and Biotechnology, Graduate School of Engineering, The University of Tokyo, Japan
- RCAST, The University of Tokyo, Japan
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9
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Shao F, Lee PW, Li H, Hsieh K, Wang TH. Emerging platforms for high-throughput enzymatic bioassays. Trends Biotechnol 2023; 41:120-133. [PMID: 35863950 PMCID: PMC9789168 DOI: 10.1016/j.tibtech.2022.06.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2022] [Revised: 05/19/2022] [Accepted: 06/14/2022] [Indexed: 12/27/2022]
Abstract
Enzymes have essential roles in catalyzing biological reactions and maintaining metabolic systems. Many in vitro enzymatic bioassays have been developed for use in industrial and research fields, such as cell biology, enzyme engineering, drug screening, and biofuel production. Of note, many of these require the use of high-throughput platforms. Although the microtiter plate remains the standard for high-throughput enzymatic bioassays, microfluidic arrays and droplet microfluidics represent emerging methods. Each has seen significant advances and offers distinct advantages; however, drawbacks in key performance metrics, including reagent consumption, reaction manipulation, reaction recovery, real-time measurement, concentration gradient range, and multiplexity, remain. Herein, we compare recent high-throughput platforms using the aforementioned metrics as criteria and provide insights into remaining challenges and future research trends.
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Affiliation(s)
- Fangchi Shao
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, USA
| | - Pei-Wei Lee
- Department of Mechanical Engineering, Johns Hopkins University, Baltimore, MD, USA
| | - Hui Li
- Department of Mechanical Engineering, Johns Hopkins University, Baltimore, MD, USA
| | - Kuangwen Hsieh
- Department of Mechanical Engineering, Johns Hopkins University, Baltimore, MD, USA
| | - Tza-Huei Wang
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, USA; Department of Mechanical Engineering, Johns Hopkins University, Baltimore, MD, USA.
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10
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Regulation of the mammalian-brain V-ATPase through ultraslow mode-switching. Nature 2022; 611:827-834. [PMID: 36418452 DOI: 10.1038/s41586-022-05472-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Accepted: 10/21/2022] [Indexed: 11/24/2022]
Abstract
Vacuolar-type adenosine triphosphatases (V-ATPases)1-3 are electrogenic rotary mechanoenzymes structurally related to F-type ATP synthases4,5. They hydrolyse ATP to establish electrochemical proton gradients for a plethora of cellular processes1,3. In neurons, the loading of all neurotransmitters into synaptic vesicles is energized by about one V-ATPase molecule per synaptic vesicle6,7. To shed light on this bona fide single-molecule biological process, we investigated electrogenic proton-pumping by single mammalian-brain V-ATPases in single synaptic vesicles. Here we show that V-ATPases do not pump continuously in time, as suggested by observing the rotation of bacterial homologues8 and assuming strict ATP-proton coupling. Instead, they stochastically switch between three ultralong-lived modes: proton-pumping, inactive and proton-leaky. Notably, direct observation of pumping revealed that physiologically relevant concentrations of ATP do not regulate the intrinsic pumping rate. ATP regulates V-ATPase activity through the switching probability of the proton-pumping mode. By contrast, electrochemical proton gradients regulate the pumping rate and the switching of the pumping and inactive modes. A direct consequence of mode-switching is all-or-none stochastic fluctuations in the electrochemical gradient of synaptic vesicles that would be expected to introduce stochasticity in proton-driven secondary active loading of neurotransmitters and may thus have important implications for neurotransmission. This work reveals and emphasizes the mechanistic and biological importance of ultraslow mode-switching.
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11
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Noji H, Minagawa Y, Ueno H. Enzyme-based digital bioassay technology - key strategies and future perspectives. LAB ON A CHIP 2022; 22:3092-3109. [PMID: 35861036 DOI: 10.1039/d2lc00223j] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Digital bioassays based on single-molecule enzyme reactions represent a new class of bioanalytical methods that enable the highly sensitive detection of biomolecules in a quantitative manner. Since the first reports of these methods in the 2000s, there has been significant growth in this new bioanalytical strategy. The principal strategy of this method is to compartmentalize target molecules in micron-sized reactors at the single-molecule level and count the number of microreactors showing positive signals originating from the target molecule. A representative application of digital bioassay is the digital enzyme-linked immunosorbent assay (ELISA). Owing to their versatility, various types of digital ELISAs have been actively developed. In addition, some disease markers and viruses possess catalytic activity, and digital bioassays for such enzymes and viruses have, thus, been developed. Currently, with the emergence of new microreactor technologies, the targets of this methodology are expanding from simple enzymes to more complex systems, such as membrane transporters and cell-free gene expression. In addition, multiplex or multiparametric digital bioassays have been developed to assess precisely the heterogeneities in sample molecules/systems that are obscured by ensemble measurements. In this review, we first introduce the basic concepts of digital bioassays and introduce a range of digital bioassays. Finally, we discuss the perspectives of new classes of digital bioassays and emerging fields based on digital bioassay technology.
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Affiliation(s)
- Hiroyuki Noji
- Department of Applied Chemistry, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, Japan.
| | - Yoshihiro Minagawa
- Department of Applied Chemistry, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, Japan.
| | - Hiroshi Ueno
- Department of Applied Chemistry, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, Japan.
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12
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Baxani DK, Jamieson WD, Barrow DA, Castell OK. Encapsulated droplet interface bilayers as a platform for high-throughput membrane studies. SOFT MATTER 2022; 18:5089-5096. [PMID: 35766018 PMCID: PMC9277618 DOI: 10.1039/d1sm01111a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Accepted: 06/09/2022] [Indexed: 06/15/2023]
Abstract
Whilst it is highly desirable to produce artificial lipid bilayer arrays allowing for systematic high-content screening of membrane conditions, it remains a challenge due to the combined requirements of scaled membrane production, simple measurement access, and independent control over individual bilayer experimental conditions. Here, droplet bilayers encapsulated within a hydrogel shell are output individually into multi-well plates for simple, arrayed quantitative measurements. The afforded experimental throughput is used to conduct a 2D concentration screen characterising the synergistic pore-forming peptides Magainin2 and PGLa. Maximal enhanced activity is revealed at equimolar peptide concentrations via a membrane dye leakage assay, a finding consistent with models proposed from NMR data. The versatility of the platform is demonstrated by performing in situ electrophysiology, revealing low conductance pore activity (∼15 to 20 pA with 4.5 pA sub-states). In conclusion, this array platform addresses the aforementioned challenges and provides new and flexible opportunities for high-throughput membrane studies. Furthermore, the ability to engineer droplet networks within each construct paves the way for "lab-in-a-capsule" approaches accommodating multiple assays per construct and allowing for communicative reaction pathways.
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Affiliation(s)
- D K Baxani
- College of Biomedical and Life Sciences, School of Pharmacy and Pharmaceutical Sciences, Cardiff University Redwood Building, King Edward VII Avenue, CF10 3NB Cardiff, UK.
| | - W D Jamieson
- College of Biomedical and Life Sciences, School of Pharmacy and Pharmaceutical Sciences, Cardiff University Redwood Building, King Edward VII Avenue, CF10 3NB Cardiff, UK.
| | - D A Barrow
- School of Engineering, Cardiff University, 14-17 The Parade, CF4 3AA Cardiff, UK
| | - O K Castell
- College of Biomedical and Life Sciences, School of Pharmacy and Pharmaceutical Sciences, Cardiff University Redwood Building, King Edward VII Avenue, CF10 3NB Cardiff, UK.
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13
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Yaginuma H, Ohtake K, Akamatsu T, Noji H, Tabata KV. A microreactor sealing method using adhesive tape for digital bioassays. LAB ON A CHIP 2022; 22:2001-2010. [PMID: 35481587 DOI: 10.1039/d2lc00065b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Digital assays using microreactors fabricated on solid substrates are useful for carrying out sensitive assays of infectious diseases and other biological tests. However, sealing of the microchambers using fluid oil is difficult for non-experts, and thus hinders the widespread use of digital microreactor assays. Here, we propose the physical isolation of tiny reactors with adhesive tape (PITAT) using simple, commercially available pressure-sensitive adhesive (PSA) tape as a separator of the microreactors. We confirmed that PSA tape can effectively seal the microreactors and prevent molecules from diffusing out. By testing several types of adhesive tape, we found that rubber-based adhesives are the most suitable for this purpose. In addition, we demonstrated that single-molecule enzyme assays can be successfully performed inside microreactors sealed with PSA tape. The results obtained using PITAT are quantitatively comparable to conventional oil sealing, although it is quick and cost-effective. Finally, we demonstrated that single-particle virus counting of the influenza virus can be achieved using PITAT. Collectively, our results suggest that PITAT may be suitable for use in the design of sensitive tests for infectious diseases at the point of care, where no sophisticated equipment or machines are available.
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Affiliation(s)
- Hideyuki Yaginuma
- Department of Applied Chemistry, Graduate School of Engineering, The University of Tokyo, Tokyo, Japan.
| | - Kuniko Ohtake
- Department of Applied Chemistry, Graduate School of Engineering, The University of Tokyo, Tokyo, Japan.
| | - Takako Akamatsu
- Department of Applied Chemistry, Graduate School of Engineering, The University of Tokyo, Tokyo, Japan.
| | - Hiroyuki Noji
- Department of Applied Chemistry, Graduate School of Engineering, The University of Tokyo, Tokyo, Japan.
| | - Kazuhito V Tabata
- Department of Applied Chemistry, Graduate School of Engineering, The University of Tokyo, Tokyo, Japan.
- Sothis Technologies, Tokyo, Japan
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14
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Usman M, Bokhari SAM, Fatima B, Rashid B, Nadeem F, Sarwar MB, Nawaz-ul-Rehman MS, Shahid M, Ayub CM. Drought Stress Mitigating Morphological, Physiological, Biochemical, and Molecular Responses of Guava ( Psidium guajava L.) Cultivars. FRONTIERS IN PLANT SCIENCE 2022; 13:878616. [PMID: 35720611 PMCID: PMC9201916 DOI: 10.3389/fpls.2022.878616] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Accepted: 04/07/2022] [Indexed: 05/08/2023]
Abstract
Guava (Psidium guajava L.), a major fruit crop of the sub-tropical region, is facing a production decline due to drought stress. Morphophysiological responses to drought stress and underlying transcriptional regulations in guava are, largely, unknown. This study evaluated the drought stress tolerance of two guava cultivars, viz. "Gola" and "Surahi," at morphological and physiological levels regulated differentially by ESTs (Expressed Sequence Tags). The treatments comprises three moisture regimes, viz. To = 100% (control), T1 = 75%, and T2 = 50% of field capacity. There was an overall decrease in both morphological and physiological attributes of studied guava cultivars in response to drought stress. Nonetheless, the water use efficiency of the "Surahi" cultivar increased (41.86%) speculating its higher drought tolerance based on enhanced peroxidase (402%) and catalase (170.21%) activities under 50% field capacity (T2). Moreover, higher proline and flavonoid contents reinforced drought stress retaliation of the "Surahi" cultivar. The differential expression of a significant number of ESTs in "Surahi" (234) as compared to "Gola" (117) cultivar, somehow, regulated its cellular, biological, and molecular functions to strengthen morphophysiological attributes against drought stress as indicated by the upregulation of ESTs related to peroxidase, sucrose synthase (SUS), alcohol dehydrogenase (ADH), and ubiquitin at morphological, biochemical, and physiological levels. In conclusion, the drought stress acclimation of pear-shaped guava cultivar "Surahi" is due to the increased activities of peroxidase (POD) and catalase (CAT) complimented by the upregulation of related ESTs.
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Affiliation(s)
- Muhammad Usman
- Institute of Horticultural Sciences, University of Agriculture, Faisalabad, Pakistan
- *Correspondence: Muhammad Usman
| | - Syeda Anum Masood Bokhari
- Institute of Horticultural Sciences, University of Agriculture, Faisalabad, Pakistan
- Department of Horticulture, Muhammad Nawaz Sharif University of Agriculture, Multan, Pakistan
| | - Bilquees Fatima
- Institute of Horticultural Sciences, University of Agriculture, Faisalabad, Pakistan
| | - Bushra Rashid
- Centre of Excellence in Molecular Biology, University of the Punjab, Lahore, Pakistan
- Bushra Rashid
| | - Faisal Nadeem
- Department of Soil Science, Faculty of Agricultural Sciences, University of the Punjab, Lahore, Pakistan
| | - Muhammad Bilal Sarwar
- Centre of Excellence in Molecular Biology, University of the Punjab, Lahore, Pakistan
| | | | - Muhammad Shahid
- Department of Biochemistry, University of Agriculture, Faisalabad, Pakistan
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15
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Xiong Y, Cao G, Chen X, Yang J, Shi M, Wang Y, Nie F, Huo D, Hou C. One-pot platform for rapid detecting virus utilizing recombinase polymerase amplification and CRISPR/Cas12a. Appl Microbiol Biotechnol 2022; 106:4607-4616. [PMID: 35708748 PMCID: PMC9201268 DOI: 10.1007/s00253-022-12015-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Revised: 05/28/2022] [Accepted: 06/04/2022] [Indexed: 02/07/2023]
Abstract
The livestock industry has been deeply affected by African swine fever virus (ASFV) and Capripoxvirus (CaPV), which caused an enormous economic damage. It is emergent to develop a reliable detection method. Here, we developed a rapid, ultra-sensitive, and one-pot DNA detection method combining recombinase polymerase amplification (RPA) and CRISPR/Cas12a for ASFV and CaPV, named one-pot-RPA-Cas12a (OpRCas) platform. It had the virtue of both RPA and CRISPR/Cas12a, such as high amplification efficiency, constant temperature reaction, and strict target selectivity, which made diagnosis simplified, accurate and easy to be operated without expensive equipment. Meanwhile, the reagents of RPA and CRISPR/Cas12a were added to the lid and bottom of tube in one go, which overcame the incompatibility of two reactions and aerosol contamination. To save cost, we only need a quarter of the amount of regular RPA per reaction which is enough to achieve clinical diagnosis. The OpRCas platform was 10 to 100 times more sensitive than qPCR; the limit of detection (LOD) was as low as 1.2 × 10-6 ng/µL (3.07 copies/µL by ddPCR) of ASFV and 7.7 × 10-5 ng/µL (1.02 copies/µL by ddPCR) of CaPV with the portable fluorometer in 40 min. In addition, the OpRCas platform combined with the lateral flow assay (LFA) strip to suit for point-of-care (POC) testing. It showed 93.3% consistency with qPCR for clinical sample analysis. Results prove that OpRCas platform is an easy-handling, ultra-sensitive, and rapid to achieve ASFV and CaPV POC testing. KEY POINTS: • The platform realizes one-pot reaction of RPA and Cas12a. • Sensitivity is 100 times more than qPCR. • Three output modes are suitable to be used to quantitative test or POC testing.
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Affiliation(s)
- Yifan Xiong
- Key Laboratory for Biorheological Science and Technology of Ministry of Education, State and Local Joint Engineering Laboratory for Vascular Implants, Bioengineering College of Chongqing University, Chongqing, 400044, People's Republic of China
| | - Gaihua Cao
- Key Laboratory for Biorheological Science and Technology of Ministry of Education, State and Local Joint Engineering Laboratory for Vascular Implants, Bioengineering College of Chongqing University, Chongqing, 400044, People's Republic of China
| | - Xiaolong Chen
- Key Laboratory for Biorheological Science and Technology of Ministry of Education, State and Local Joint Engineering Laboratory for Vascular Implants, Bioengineering College of Chongqing University, Chongqing, 400044, People's Republic of China
| | - Jun Yang
- State Key Laboratory of Cattle Diseases Detection (Chongqing), Chongqing Customs, Chongqing Customs Technology Center, Chongqing, 400020, People's Republic of China
| | - Meimei Shi
- State Key Laboratory of Cattle Diseases Detection (Chongqing), Chongqing Customs, Chongqing Customs Technology Center, Chongqing, 400020, People's Republic of China
| | - Yu Wang
- State Key Laboratory of Cattle Diseases Detection (Chongqing), Chongqing Customs, Chongqing Customs Technology Center, Chongqing, 400020, People's Republic of China
| | - Fuping Nie
- State Key Laboratory of Cattle Diseases Detection (Chongqing), Chongqing Customs, Chongqing Customs Technology Center, Chongqing, 400020, People's Republic of China.
| | - Danqun Huo
- Key Laboratory for Biorheological Science and Technology of Ministry of Education, State and Local Joint Engineering Laboratory for Vascular Implants, Bioengineering College of Chongqing University, Chongqing, 400044, People's Republic of China.
| | - Changjun Hou
- Key Laboratory for Biorheological Science and Technology of Ministry of Education, State and Local Joint Engineering Laboratory for Vascular Implants, Bioengineering College of Chongqing University, Chongqing, 400044, People's Republic of China.
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16
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Murahara H, Kaji N, Tokeshi M, Baba Y. Enzyme kinetics in confined geometries at the single enzyme level. Analyst 2022; 147:1375-1384. [DOI: 10.1039/d1an02024b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Different confinement, femtoliter chambers and molecular crowders revealed the effects on the catalytic rates of β-galactosidase at the single molecule level.
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Affiliation(s)
- Hisashi Murahara
- Department of Biomolecular Engineering, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan
| | - Noritada Kaji
- Department of Applied Chemistry, Graduate School of Engineering, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
- Institute of Nano-Life-Systems, Institutes of Innovation for Future Society, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan
| | - Manabu Tokeshi
- Institute of Nano-Life-Systems, Institutes of Innovation for Future Society, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan
- Division of Applied Chemistry, Faculty of Engineering, Hokkaido University, Kita-13, Nishi-8, Kita-Ku, Sapporo 060-8628, Japan
| | - Yoshinobu Baba
- Department of Biomolecular Engineering, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan
- Institute of Nano-Life-Systems, Institutes of Innovation for Future Society, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan
- Institute of Quantum Life Science, National Institutes for Quantum and Radiological Science and Technology, Chiba, 263-8555, Japan
- School of Pharmacy, College of Pharmacy, Kaohsiung Medical University, 100, Shih-Chuan 1st Rd., Kaohsiung, 807, Taiwan, Republic of China
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17
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Ohnishi S, Kamiya K. Formation of Giant Lipid Vesicle Containing Dual Functions Facilitates Outer Membrane Phospholipase. ACS Synth Biol 2021; 10:1837-1846. [PMID: 34258991 DOI: 10.1021/acssynbio.0c00468] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Giant lipid vesicles are used to study artificial cell models, as well as the encapsulation of biomolecules, and the reconstitution of membrane proteins on these vesicles. Recently, complex reactions in giant vesicles have been controlled by reconstituting numerous kinds of biomolecules. However, it is challenging to generate giant lipid vesicles containing a diverse set of proteins at concentrations sufficient to ensure proper functioning. Here, we describe an artificial cell model showing dual functions of small molecule transportation and small vesicle budding, using a dual functional membrane protein (transportation and phosphatase activity) called the outer membrane phospholipase (OmpLA). To the best of our knowledge, we have revealed for the first time the transportation of ions or small molecules through OmpLA on the charged lipid bilayer. The lipid composition controlled the orientation of OmpLA through proteinase K digestion. Finally, OmpLA enzyme activity of phospholipid hydrolysis caused the budding of small vesicles.
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Affiliation(s)
- Seren Ohnishi
- Division of Molecular Science, Graduate School of Science and Technology, Gunma University, 1-5-1 Tenjin-cho, Kiryu, Gunma 376-8515, Japan
| | - Koki Kamiya
- Division of Molecular Science, Graduate School of Science and Technology, Gunma University, 1-5-1 Tenjin-cho, Kiryu, Gunma 376-8515, Japan
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18
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Diederichs T, Tampé R. Membrane-Suspended Nanopores in Microchip Arrays for Stochastic Transport Recording and Sensing. FRONTIERS IN NANOTECHNOLOGY 2021. [DOI: 10.3389/fnano.2021.703673] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The transport of nutrients, xenobiotics, and signaling molecules across biological membranes is essential for life. As gatekeepers of cells, membrane proteins and nanopores are key targets in pharmaceutical research and industry. Multiple techniques help in elucidating, utilizing, or mimicking the function of biological membrane-embedded nanodevices. In particular, the use of DNA origami to construct simple nanopores based on the predictable folding of nucleotides provides a promising direction for innovative sensing and sequencing approaches. Knowledge of translocation characteristics is crucial to link structural design with function. Here, we summarize recent developments and compare features of membrane-embedded nanopores with solid-state analogues. We also describe how their translocation properties are characterized by microchip systems. The recently developed silicon chips, comprising solid-state nanopores of 80 nm connecting femtoliter cavities in combination with vesicle spreading and formation of nanopore-suspended membranes, will pave the way to characterize translocation properties of nanopores and membrane proteins in high-throughput and at single-transporter resolution.
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19
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Ueno H, Kato M, Minagawa Y, Hirose Y, Noji H. Elucidation and control of low and high active populations of alkaline phosphatase molecules for quantitative digital bioassay. Protein Sci 2021; 30:1628-1639. [PMID: 33955095 PMCID: PMC8284569 DOI: 10.1002/pro.4102] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Revised: 04/27/2021] [Accepted: 05/02/2021] [Indexed: 12/13/2022]
Abstract
Alkaline phosphatase (ALP), a homo‐dimeric enzyme has been widely used in various bioassays as disease markers and enzyme probes. Recent advancements of digital bioassay revolutionized ALP‐based diagnostic assays as seen in rapid growth of digital ELISA and the emerging multiplex profiling of single‐molecule ALP isomers. However, the intrinsic heterogeneity found among ALP molecules hampers the ALP‐based quantitative digital bioassays. This study aims quantitative analysis of single‐molecule activities of ALP from Escherichia coli and reveals the static heterogeneity in catalytic activity of ALP with two distinct populations: half‐active and fully‐active portions. Digital assays with serial buffer exchange uncovered single‐molecule Michaelis–Menten kinetics of ALP; half‐active molecules have halved values of the catalytic turnover rate, kcat, and the rate constant of productive binding, kon, of the fully active molecules. These findings suggest that half‐active ALP molecules are heterogenic dimers composed of inactive and active monomer units, while fully active ALP molecules comprise two active units. Static heterogeneity was also observed for ALP with other origins: calf intestine or shrimp, showing how the findings can be generalized across species. Cell‐free expression of ALP with disulfide bond enhancer and spiked zinc ion resulted in homogenous population of ALP of full activity, implying that inactive monomer units of ALP are deficient in correct disulfide bond formation and zinc ion coordination. These findings provide basis for further study on molecular mechanism and biogenesis of ALP, and also offer the way to prepare homogenous and active populations of ALP for highly quantitative and sensitive bioassays with ALP.
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Affiliation(s)
- Hiroshi Ueno
- Department of Applied Chemistry, Graduate School of Engineering, The University of Tokyo, Tokyo, Japan
| | - Makoto Kato
- Department of Applied Chemistry, Graduate School of Engineering, The University of Tokyo, Tokyo, Japan
| | - Yoshihiro Minagawa
- Department of Applied Chemistry, Graduate School of Engineering, The University of Tokyo, Tokyo, Japan
| | - Yushi Hirose
- Department of Applied Chemistry, Graduate School of Engineering, The University of Tokyo, Tokyo, Japan
| | - Hiroyuki Noji
- Department of Applied Chemistry, Graduate School of Engineering, The University of Tokyo, Tokyo, Japan
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20
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Abstract
Biological membranes composed of a lipid bilayer and associated proteins work as a platform for highly selective and sensitive detection in nature. Substrate-supported lipid bilayers (SLBs) are a model system of the biological membrane that are mechanically stable, accessible to highly sensitive analytical techniques, and amenable to micro-fabrication, such as patterning. The surface of SLBs can effectively suppress the non-specific binding of proteins, and enhance selective detection by specific interactions. These features render SLBs highly attractive for the development of devices that utilize artificially mimicked cellular functions. Furthermore, SLBs can be combined with nanoscopic spaces, such as nano-channels and nano-pores, that can reduce the detection volume and suppress the non-specific background noise, enhancing the signal-to-background noise (S/B) ratio. SLBs therefore provide promising platforms for a wide range of biomedical and environmental analyses.
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Affiliation(s)
- Kenichi Morigaki
- Biosignal Research Center, Kobe University.,Graduate School of Agricultural Science, Kobe University
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21
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Abstract
CRISPR-based nucleic-acid detection is an emerging technology for molecular diagnostics. However, these methods generally require several hours and could cause amplification errors, due to the pre-amplification of target nucleic acids to enhance the detection sensitivity. Here, we developed a platform that allows “CRISPR-based amplification-free digital RNA detection (SATORI)”, by combining CRISPR-Cas13-based RNA detection and microchamber-array technologies. SATORI detected single-stranded RNA targets with maximal sensitivity of ~10 fM in <5 min, with high specificity. Furthermore, the simultaneous use of multiple different guide RNAs enhanced the sensitivity, thereby enabling the detection of the SARS-CoV-2 N-gene RNA at ~5 fM levels. Therefore, we hope SATORI will serve as a powerful class of accurate and rapid diagnostics. The authors develop a platform (SATORI) that enables accurate and rapid detection of single-stranded RNA at a single-molecule level without a pre-amplification step. As a proof-of-concept, they demonstrate its utility in detecting the SARS-CoV-2 N gene at a minimum concentration of ~5 fM, which is much lower than other amplification-free CRISPR-Cas-based methods.
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22
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Parperis C, Wallace MI. Single-molecule imaging of pore-forming toxin dynamics in droplet interface bilayers. Methods Enzymol 2021; 649:431-459. [PMID: 33712195 DOI: 10.1016/bs.mie.2021.01.035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Single-channel recording from pore-forming toxins (PFTs) provides a clear and direct molecular readout of toxin action. However to complete any mechanistic understanding of PFT behavior, this functional kinetic readout must be linked to the underlying changes in toxin structure, binding, conformation, or stoichiometry. Here we review how single-molecule imaging methods might be used to further our understanding of PFTs, and provide detailed practical guidance on the use of droplet interface bilayers as a method capable of examining both single-molecule fluorescence and single-channel electrical signals from PFTs.
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Affiliation(s)
- Christopher Parperis
- Department of Chemistry, Britannia House, King's College London, London, United Kingdom
| | - Mark I Wallace
- Department of Chemistry, Britannia House, King's College London, London, United Kingdom.
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23
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Pannwitz A, Saaring H, Beztsinna N, Li X, Siegler MA, Bonnet S. Mimicking Photosystem I with a Transmembrane Light Harvester and Energy Transfer-Induced Photoreduction in Phospholipid Bilayers. Chemistry 2021; 27:3013-3018. [PMID: 32743875 PMCID: PMC7898337 DOI: 10.1002/chem.202003391] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Indexed: 11/19/2022]
Abstract
Photosystem I (PS I) is a transmembrane protein that assembles perpendicular to the membrane, and performs light harvesting, energy transfer, and electron transfer to a final, water-soluble electron acceptor. We present here a supramolecular model of it formed by a bicationic oligofluorene 12+ bound to the bisanionic photoredox catalyst eosin Y (EY2- ) in phospholipid bilayers. According to confocal microscopy, molecular modeling, and time dependent density functional theory calculations, 12+ prefers to align perpendicularly to the lipid bilayer. In presence of EY2- , a strong complex is formed (Ka =2.1±0.1×106 m-1 ), which upon excitation of 12+ leads to efficient energy transfer to EY2- . Follow-up electron transfer from the excited state of EY2- to the water-soluble electron donor EDTA was shown via UV-Vis absorption spectroscopy. Overall, controlled self-assembly and photochemistry within the membrane provides an unprecedented yet simple synthetic functional mimic of PS I.
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Affiliation(s)
- Andrea Pannwitz
- Leiden UniversityLeiden Institute of ChemistryEinsteinweg 55, 2333CCLeidenThe Netherlands
| | - Holden Saaring
- Leiden UniversityLeiden Institute of ChemistryEinsteinweg 55, 2333CCLeidenThe Netherlands
| | - Nataliia Beztsinna
- Leiden UniversityLeiden Institute of ChemistryEinsteinweg 55, 2333CCLeidenThe Netherlands
| | - Xinmeng Li
- Leiden UniversityLeiden Institute of ChemistryEinsteinweg 55, 2333CCLeidenThe Netherlands
| | - Maxime A. Siegler
- Johns Hopkins UniversityDepartment of ChemistryMaryland21218BaltimoreUSA
| | - Sylvestre Bonnet
- Leiden UniversityLeiden Institute of ChemistryEinsteinweg 55, 2333CCLeidenThe Netherlands
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24
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Yasuhara K, Morigaki K. New lipid membrane technologies for reconstitution, analysis, and utilization of 'living' membrane proteins. Biophys Physicobiol 2020; 17:125-129. [PMID: 33240738 PMCID: PMC7671742 DOI: 10.2142/biophysico.bsj-2020021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Accepted: 08/28/2020] [Indexed: 12/01/2022] Open
Affiliation(s)
- Kazuma Yasuhara
- Division of Materials Science, Graduate School of Science and Technology, Nara Institute of Science and Technology, Ikoma, Nara 630-0192, Japan
| | - Kenichi Morigaki
- Biosignal Research Center, Kobe University, Kobe, Hyogo 657-8501, Japan.,Graduate School of Agricultural Science, Kobe University, Kobe, Hyogo 657-8501, Japan
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25
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Cochereau R, Renard D, Noûs C, Boire A. Semi-permeable vesicles produced by microfluidics to tune the phase behaviour of encapsulated macromolecules. J Colloid Interface Sci 2020; 580:709-719. [PMID: 32712477 DOI: 10.1016/j.jcis.2020.07.022] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 06/28/2020] [Accepted: 07/05/2020] [Indexed: 12/11/2022]
Abstract
Understanding the dynamics of macromolecular assemblies in solution, such as Liquid-Liquid Phase Separation (LLPS), represents technologic and fundamental challenges in many fields. In cell biology, such dynamics are of great interest, because of their involvement in subcellular processes. In our study, we aimed to control the assembly of macromolecules in aqueous semi-permeable vesicles, that we named osmosomes, using microfluidics. We developed a microfluidic chip that allows for producting and trapping Giant Unilamellar Vesicles (GUVs) encapsulating macromolecules. This device also allows for modification of the composition of the inner phase and of the membranes of the trapped GUVs. The vesicles are produced from water-in-oil-in-water (w/o/w) double emulsions in less than 20 min after discarding the oil phase. They are highly monodisperse and their diameter can be modulated between 20 and 110 µm by tuning the flow rates of fluid phases. Their unilamellarity is proofed by two techniques: (1) fluorescence quenching experiments and (2) the insertion of the α-hemolysin membrane protein pore. We demonstrate that the internal pH of osmosomes can be tuned in less than 1 min by controlling solvent exchanges through the α-hemolysin pores. The detailed analysis of the exchange kinetics suggests that the microfluidic chip provides an efficient pore formation due to the physical trapping of vesicles and the constant flow rate. Finally, we show a proof of concept for macromolecular assembly within osmosomes by pH-triggered LLPS of wheat proteins within a few minutes.
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26
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Lee HR, Lee Y, Oh SS, Choi SQ. Ultra-Stable Freestanding Lipid Membrane Array: Direct Visualization of Dynamic Membrane Remodeling with Cholesterol Transport and Enzymatic Reactions. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2020; 16:e2002541. [PMID: 32924281 DOI: 10.1002/smll.202002541] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Revised: 07/09/2020] [Indexed: 06/11/2023]
Abstract
Cell membranes actively change their local compositions, serving essential biological processes such as cellular signaling and endocytosis. Although membrane dynamics is vital in the cellular functions, the complexity of natural membranes has made its fundamental understanding and systematic assessment difficult. Here, a powerful artificial membrane system is developed for real-time visualization of the spatiotemporal dynamics of membrane remodeling. Through well-defined air/oil/water interfaces on grid holes, tens of planar lipid bilayer membranes are easily created, and their reproducibility, controllability, and generality are highlighted. The freestanding membranes are large but also highly stable, facilitating direct long-term monitoring of dynamic membrane reconstitution caused by external stimuli. As an example to demonstrate the superiority of this membrane system, the effect of cholesterol trafficking, which significantly affects biophysical properties of cell membranes, is investigated at different membrane compositions. Cholesterol transport into and out of the membranes at different rates causes anomalous lipid arrangements through cholesterol-mediated phase transitions and decomposition, which have never been witnessed before. Furthermore, enzyme-induced membrane dynamics is successfully shown in this platform; sphingomyelinases locally generate asymmetry between two membrane leaflets. This technique is broadly applicable for exploring the membrane heterogeneity under various membrane-based reactions, providing valuable insight into the membrane dynamics.
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Affiliation(s)
- Hyun-Ro Lee
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
| | - Yohan Lee
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
| | - Seung Soo Oh
- Department of Materials Science and Engineering, Pohang University of Science and Technology (POSTECH), Pohang, 37673, Republic of Korea
| | - Siyoung Q Choi
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
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27
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Soga N, Ota A, Nakajima K, Watanabe R, Ueno H, Noji H. Monodisperse Liposomes with Femtoliter Volume Enable Quantitative Digital Bioassays of Membrane Transporters and Cell-Free Gene Expression. ACS NANO 2020; 14:11700-11711. [PMID: 32864949 DOI: 10.1021/acsnano.0c04354] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Digital bioassays have emerged as a new category of bioanalysis. However, digital bioassays for membrane transporter proteins have not been well established yet despite high demands in molecular physiology and molecular pharmacology due to the lack of biologically functional monodisperse liposomes with femtoliter volumes. Here, we established a simple and robust method to produce femtoliter-sized liposomes (femto-liposomes). We prepared 106 monodispersed water-in-oil droplets stabilized by a lipid monolayer using a polyethylene glycol-coated femtoliter reactor array device. Droplets were subjected to the optimized emulsion transfer process for femto-liposome production. Liposomes were monodispersed (coefficient of variation = 5-15%) and had suitable diameter (0.6-5.3 μm) and uniform volumes of subfemtoliter or a few femtoliters; thus, they were termed uniform femto-liposomes. The unilamellarity of uniform femto-liposomes allowed quantitative single-molecule analysis of passive and active transporter proteins: α-hemolysin and FoF1-ATPase. Digital gene expression in uniform femto-liposomes (cell-free transcription and translation from single DNA molecules) was also demonstrated, showing the versatility of digital assays for membrane transporter proteins and cell-free synthetic biology.
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Affiliation(s)
- Naoki Soga
- Department of Applied Chemistry, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Akira Ota
- Department of Applied Chemistry, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Kota Nakajima
- Department of Applied Chemistry, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Rikiya Watanabe
- Department of Applied Chemistry, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
- PRIME, Japan Agency for Medical Research and Development, 1-7-1 Otemachi, Chiyoda-ku, Tokyo 100-0004, Japan
| | - Hiroshi Ueno
- Department of Applied Chemistry, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Hiroyuki Noji
- Department of Applied Chemistry, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
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28
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Komatsu T, Kyo E, Ishii H, Tsuchikama K, Yamaguchi A, Ueno T, Hanaoka K, Urano Y. Antibody Clicking as a Strategy to Modify Antibody Functionalities on the Surface of Targeted Cells. J Am Chem Soc 2020; 142:15644-15648. [DOI: 10.1021/jacs.0c05331] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Toru Komatsu
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Etsu Kyo
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Haruki Ishii
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Kyoji Tsuchikama
- Texas Therapeutics Institute, The Brown Foundation Institute of Molecular Medicine, The University of Texas Health Science Center at Houston, 1881 East Road, Houston, Texas 77054, United States
| | - Aiko Yamaguchi
- Texas Therapeutics Institute, The Brown Foundation Institute of Molecular Medicine, The University of Texas Health Science Center at Houston, 1881 East Road, Houston, Texas 77054, United States
| | - Tasuku Ueno
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Kenjiro Hanaoka
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Yasuteru Urano
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
- Graduate School of Medicine, The University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
- Core Research for Evolutional Science and Technology (CREST), Japan Agency for Medical Research and Development (AMED), 1-7-1 Otemachi, Chiyoda-ku, Tokyo 100-0004, Japan
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29
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Tawfik H, Puza S, Seemann R, Fleury JB. Transport Properties of Gramicidin A Ion Channel in a Free-Standing Lipid Bilayer Filled With Oil Inclusions. Front Cell Dev Biol 2020; 8:531229. [PMID: 33015051 PMCID: PMC7498540 DOI: 10.3389/fcell.2020.531229] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Accepted: 08/14/2020] [Indexed: 11/13/2022] Open
Abstract
Ion channels are key proteins in mammalian cell membranes. They have a central role in the physiology of excitable cells such as neurons, muscle, and heart cells. They also play a crucial role in kidney physiology. The gramicidin ion channel is one of the most studied ion channels, in particular it was intensively employed to investigate the lipid–protein interactions in model cell membranes. For example, even though the sequence of gramicidin is extremely hydrophobic, its motion is impaired in membrane bilayer, i.e., it does not rapidly flip to the other membrane leaflet, and low channel activity were observed when gramicidin is added asymmetrically to only one leaflet of a model cell membrane. In this article, we study the transport properties of gramicidin channel in a heterogeneous model membrane. Using microfluidics, we are forming freestanding bilayers as model cell membranes including heterogeneous domains that are created by oil inclusions. The presence of oil inclusions is then demonstrated by measuring the bilayer capacity via a patch-clamp amplifier and fluorescent confocal inspection. Based on electrophysiological and optical measurements Gramicidin A (gA) ion channels are dispersed into the buffer phases on both side of the formed lipid bilayer and insert spontaneously into the bilayer upon formation. The presence of functional Gramicidin A is then demonstrated by measuring conductivity signals. Based on electrophysiological and optical measurements, we explore the consequence of the presence of these oil inclusions on the functionality of incorporated gA ion channels. For low oil concentration, we measure a decrease of gA transport properties due to the reduction of the bilayer tension. For large oil concentration, we measure a saturation of gA transport properties due to an increase of the bilayer thickness.
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Affiliation(s)
- Harvey Tawfik
- Experimental Physics and Center for Biophysics, Universität des Saarlandes, Saarbrücken, Germany
| | - Sevde Puza
- Experimental Physics and Center for Biophysics, Universität des Saarlandes, Saarbrücken, Germany
| | - Ralf Seemann
- Experimental Physics and Center for Biophysics, Universität des Saarlandes, Saarbrücken, Germany
| | - Jean-Baptiste Fleury
- Experimental Physics and Center for Biophysics, Universität des Saarlandes, Saarbrücken, Germany
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30
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Kimura T, Suzuki A, Yang Y, Niida Y, Nishioka A, Takei M, Wei J, Mitomo H, Matsuo Y, Niikura K, Ijiro K, Tono K, Yabashi M, Ishikawa T, Oshima T, Bessho Y, Joti Y, Nishino Y. Micro-liquid enclosure array and its semi-automated assembling system for x-ray free-electron laser diffractive imaging of samples in solution. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2020; 91:083706. [PMID: 32872956 DOI: 10.1063/5.0008398] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2020] [Accepted: 07/30/2020] [Indexed: 06/11/2023]
Abstract
We developed micro-liquid enclosure arrays (MLEAs) for holding solution samples in coherent diffractive imaging (CDI) using x-ray free-electron lasers (XFELs). Hundreds of fully isolated micro-liquid enclosures are arranged in a single MLEA chip for efficient measurement, where each enclosure is destroyed after exposure to a single XFEL pulse. A semi-automated MLEA assembling system was also developed to enclose solution samples into MLEAs efficiently at high precision. We performed XFEL-based CDI experiments using MLEAs and imaged in-solution structures of self-assembled gold nanoparticles. The sample hit rate can be optimized by adjusting solution concentration, and we achieved a single-particle hit rate of 31%, which is not far from the theoretical upper limit of 37% derived from the Poisson statistics. MELAs allow us to perform CDI measurement under controlled solution conditions and will help reveal the nanostructures and dynamics of particles in solution.
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Affiliation(s)
- Takashi Kimura
- Research Institute for Electronic Science, Hokkaido University, Kita 21 Nishi 10, Kita-ku, Sapporo 001-0021, Japan
| | - Akihiro Suzuki
- Research Institute for Electronic Science, Hokkaido University, Kita 21 Nishi 10, Kita-ku, Sapporo 001-0021, Japan
| | - Ying Yang
- Research Institute for Electronic Science, Hokkaido University, Kita 21 Nishi 10, Kita-ku, Sapporo 001-0021, Japan
| | - Yoshiya Niida
- Research Institute for Electronic Science, Hokkaido University, Kita 21 Nishi 10, Kita-ku, Sapporo 001-0021, Japan
| | - Akiko Nishioka
- Research Institute for Electronic Science, Hokkaido University, Kita 21 Nishi 10, Kita-ku, Sapporo 001-0021, Japan
| | - Masashi Takei
- Research Institute for Electronic Science, Hokkaido University, Kita 21 Nishi 10, Kita-ku, Sapporo 001-0021, Japan
| | - Jinjian Wei
- Graduate School of Chemical Sciences and Engineering, Hokkaido University, Kita 13, Nishi 8, Kita-ku, Sapporo 060-8628, Japan
| | - Hideyuki Mitomo
- Research Institute for Electronic Science, Hokkaido University, Kita 21 Nishi 10, Kita-ku, Sapporo 001-0021, Japan
| | - Yasutaka Matsuo
- Research Institute for Electronic Science, Hokkaido University, Kita 21 Nishi 10, Kita-ku, Sapporo 001-0021, Japan
| | - Kenichi Niikura
- Research Institute for Electronic Science, Hokkaido University, Kita 21 Nishi 10, Kita-ku, Sapporo 001-0021, Japan
| | - Kuniharu Ijiro
- Research Institute for Electronic Science, Hokkaido University, Kita 21 Nishi 10, Kita-ku, Sapporo 001-0021, Japan
| | - Kensuke Tono
- Japan Synchrotron Radiation Research Institute/SPring-8, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5198, Japan
| | - Makina Yabashi
- RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5148, Japan
| | - Tetsuya Ishikawa
- RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5148, Japan
| | - Tairo Oshima
- Institute of Environmental Microbiology, Kyowa-kako Co. Ltd., 2-15-5 Tadao, Machida, Tokyo 194-0035, Japan
| | - Yoshitaka Bessho
- RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5148, Japan
| | - Yasumasa Joti
- Japan Synchrotron Radiation Research Institute/SPring-8, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5198, Japan
| | - Yoshinori Nishino
- Research Institute for Electronic Science, Hokkaido University, Kita 21 Nishi 10, Kita-ku, Sapporo 001-0021, Japan
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31
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Kazoe Y, Mawatari K, Li L, Emon H, Miyawaki N, Chinen H, Morikawa K, Yoshizaki A, Dittrich PS, Kitamori T. Lipid Bilayer-Modified Nanofluidic Channels of Sizes with Hundreds of Nanometers for Characterization of Confined Water and Molecular/Ion Transport. J Phys Chem Lett 2020; 11:5756-5762. [PMID: 32633535 DOI: 10.1021/acs.jpclett.0c01084] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Water inside and between cells with dimensions on the order of 101-103 nm such as synaptic clefts and mitochondria is thought to be important to biological functions, such as signal transmissions and energy production. However, the characterization of water in such spaces has been difficult owing to the small size and complexity of cellular environments. To this end, we proposed and fabricated a biomimetic nanospace exploiting nanofluidic channels with defined dimensions of hundreds of nanometers and controlled environments. A method of modifying a glass nanochannel with a unilamellar lipid bilayer was developed. We revealed that 2.1-5.6 times higher viscosity of water arises in a 200 nm sized biomimetic nanospace by interactions between water molecules and the lipid bilayer surface and significantly affects the molecular/ion transport that is required for the biological functions. The proposed method provides both a technical breakthrough and new findings to the fields of physical chemistry and biology.
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Affiliation(s)
- Yutaka Kazoe
- Department of Applied Chemistry, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-8656, Japan
| | - Kazuma Mawatari
- Department of Applied Chemistry, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-8656, Japan
- Department of Bioengineering, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-8656, Japan
| | - Lixiao Li
- Department of Bioengineering, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-8656, Japan
| | - Hisaki Emon
- Department of Applied Chemistry, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-8656, Japan
| | - Naoya Miyawaki
- Department of Applied Chemistry, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-8656, Japan
| | - Hiroyuki Chinen
- Department of Applied Chemistry, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-8656, Japan
| | - Kyojiro Morikawa
- Department of Applied Chemistry, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-8656, Japan
| | - Ayumi Yoshizaki
- Department of Dermatology, School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-8656, Japan
| | - Petra S Dittrich
- Department of Biosystems Science and Engineering, ETH Zurich, Mattenstrasse 26, CH-4058 Basel, Switzerland
| | - Takehiko Kitamori
- Department of Applied Chemistry, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-8656, Japan
- Department of Bioengineering, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-8656, Japan
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32
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Sakamoto S, Komatsu T, Watanabe R, Zhang Y, Inoue T, Kawaguchi M, Nakagawa H, Ueno T, Okusaka T, Honda K, Noji H, Urano Y. Multiplexed single-molecule enzyme activity analysis for counting disease-related proteins in biological samples. SCIENCE ADVANCES 2020; 6:eaay0888. [PMID: 32195342 PMCID: PMC7065886 DOI: 10.1126/sciadv.aay0888] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Accepted: 12/11/2019] [Indexed: 05/24/2023]
Abstract
We established an ultrasensitive method for identifying multiple enzymes in biological samples by using a multiplexed microdevice-based single-molecule enzymatic assay. We used a paradigm in which we "count" the number of enzyme molecules by profiling their single enzyme activity characteristics toward multiple substrates. In this proof-of-concept study of the single enzyme activity-based protein profiling (SEAP), we were able to detect the activities of various phosphoric ester-hydrolyzing enzymes such as alkaline phosphatases, tyrosine phosphatases, and ectonucleotide pyrophosphatases in blood samples at the single-molecule level and in a subtype-discriminating manner, demonstrating its potential usefulness for the diagnosis of diseases based on ultrasensitive detection of enzymes.
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Affiliation(s)
- Shingo Sakamoto
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Toru Komatsu
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Rikiya Watanabe
- Molecular Physiology Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Yi Zhang
- Super-cutting-edge Grand and Advanced Research (SUGAR) Program, Institute for Extra-cutting-edge Science and Technology Avant-garde Research (X-star), Japan Agency for Marine-Earth Science and Technology (JAMSTEC), 2-15 Natsushima-cho, Yokosuka 237-0061, Japan
| | - Taiki Inoue
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Mitsuyasu Kawaguchi
- Graduate School of Pharmaceutical Sciences, Nagoya City University, 3-1, Tanabedori, Mizuho-ku, Nagoya-shi, Aichi 467-8603, Japan
| | - Hidehiko Nakagawa
- Graduate School of Pharmaceutical Sciences, Nagoya City University, 3-1, Tanabedori, Mizuho-ku, Nagoya-shi, Aichi 467-8603, Japan
| | - Takaaki Ueno
- Department of Oral and Maxillofacial Surgery, Osaka Medical College, 2-7 Daigakumachi, Takatsuki-shi, Osaka 569-8686, Japan
| | - Takuji Okusaka
- Hepatobiliary and Pancreatic Oncology, National Cancer Center Hospital, 5-1-1, Tsukiji, Chuo-ku, Tokyo 104-0045, Japan
| | - Kazufumi Honda
- Department of Biomarkers for Early Detection of Cancer, National Cancer Center Research Institute, 5-1-1, Tsukiji, Chuo-ku, Tokyo 104-0045, Japan
| | - Hiroyuki Noji
- Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Yasuteru Urano
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
- Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
- Core Research for Evolutional Science and Technology (CREST) Investigator, Japan Agency for Medical Research and Development (AMED), 1-7-1 Otemachi, Chiyoda-ku, Tokyo 100-0004, Japan
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33
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Komatsu T, Urano Y. Chemical toolbox for 'live' biochemistry to understand enzymatic functions in living systems. J Biochem 2020; 167:139-149. [PMID: 31553443 DOI: 10.1093/jb/mvz074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Accepted: 08/30/2019] [Indexed: 11/12/2022] Open
Abstract
In this review, we present an overview of the recent advances in chemical toolboxes that are used to provide insights into 'live' protein functions in living systems. Protein functions are mediated by various factors inside of cells, such as protein-protein interactions, posttranslational modifications, and they are also subject to environmental factors such as pH, redox states and crowding conditions. Obtaining a true understanding of protein functions in living systems is therefore a considerably difficult task. Recent advances in research tools have allowed us to consider 'live' biochemistry as a valid approach to precisely understand how proteins function in a live cell context.
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Affiliation(s)
- Toru Komatsu
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Yasuteru Urano
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.,Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.,Core Research for Evolutional Science and Technology (CREST) Investigator, Japan Agency for Medical Research and Development (AMED), 1-7-1 Otemachi, Chiyoda-ku, Tokyo 100-0004, Japan
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34
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Suzuki A, Kimura T, Yang Y, Niida Y, Nishioka A, Tachibana T, Takei M, Tono K, Yabashi M, Ishikawa T, Oshima T, Bessho Y, Joti Y, Nishino Y. Design of a liquid cell toward three-dimensional imaging of unidirectionally-aligned particles in solution using X-ray free-electron lasers. Phys Chem Chem Phys 2020; 22:2622-2628. [DOI: 10.1039/c9cp03658j] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A liquid cell was designed for coherent diffractive imaging measurements at high tilt angles and tested at SACLA.
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35
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Mao X, Liu C, Tong H, Chen Y, Liu K. Principles of digital PCR and its applications in current obstetrical and gynecological diseases. Am J Transl Res 2019; 11:7209-7222. [PMID: 31934273 PMCID: PMC6943456] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2019] [Accepted: 12/07/2019] [Indexed: 06/10/2023]
Abstract
Digital PCR (dPCR) is a revolutionary technique to precisely quantify nucleic acids. For its high sensitivity and specificity, this technique has been widely replicated worldwide. To verify its applicability, we reviewed all the related articles in PubMed database published before May 10, 2019. Original articles and reviews on the topics were selected. Entered key words included "digital PCR/dPCR", "advantage", "combined use", "microfluidic chip", "gynecological cancer/tumor". We found that dPCR has shown great potential in clinical operations, like tumor liquid biopsy, non-invasive prenatal diagnosis, microorganism detection, and next-generation sequencing library quality-control.
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Affiliation(s)
- Xiaodong Mao
- Department of Endocrinology, Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese MedicineNanjing 210028, Jiangsu, China
| | - Chao Liu
- Department of Endocrinology, Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese MedicineNanjing 210028, Jiangsu, China
| | - Hua Tong
- Department of Obstetrics and Gynecology, Women’s Hospital of Nanjing Medical University, Nanjing Maternity and Child Health Care HospitalNanjing 210029, Jiangsu, China
| | - Yajun Chen
- Department of Clinical Laboratory, Women’s Hospital of Nanjing Medical University, Nanjing Maternity and Child Health Care HospitalNanjing 210029, Jiangsu, China
| | - Kangsheng Liu
- Department of Clinical Laboratory, Women’s Hospital of Nanjing Medical University, Nanjing Maternity and Child Health Care HospitalNanjing 210029, Jiangsu, China
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36
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Quantifying secondary transport at single-molecule resolution. Nature 2019; 575:528-534. [PMID: 31723269 DOI: 10.1038/s41586-019-1747-5] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2019] [Accepted: 10/07/2019] [Indexed: 01/07/2023]
Abstract
Secondary active transporters, which are vital for a multitude of physiological processes, use the energy of electrochemical ion gradients to power substrate transport across cell membranes1,2. Efforts to investigate their mechanisms of action have been hampered by their slow transport rates and the inherent limitations of ensemble methods. Here we quantify the activity of individual MhsT transporters, which are representative of the neurotransmitter:sodium symporter family of secondary transporters3, by imaging the transport of individual substrate molecules across lipid bilayers at both single- and multi-turnover resolution. We show that MhsT is active only when physiologically oriented and that the rate-limiting step of the transport cycle varies with the nature of the transported substrate. These findings are consistent with an extracellular allosteric substrate-binding site that modulates the rate-limiting aspects of the transport mechanism4,5, including the rate at which the transporter returns to an outward-facing state after the transported substrate is released.
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37
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Synthetic protein-conductive membrane nanopores built with DNA. Nat Commun 2019; 10:5018. [PMID: 31685824 PMCID: PMC6828756 DOI: 10.1038/s41467-019-12639-y] [Citation(s) in RCA: 62] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2016] [Accepted: 09/23/2019] [Indexed: 11/08/2022] Open
Abstract
AbstractNanopores are key in portable sequencing and research given their ability to transport elongated DNA or small bioactive molecules through narrow transmembrane channels. Transport of folded proteins could lead to similar scientific and technological benefits. Yet this has not been realised due to the shortage of wide and structurally defined natural pores. Here we report that a synthetic nanopore designed via DNA nanotechnology can accommodate folded proteins. Transport of fluorescent proteins through single pores is kinetically analysed using massively parallel optical readout with transparent silicon-on-insulator cavity chips vs. electrical recordings to reveal an at least 20-fold higher speed for the electrically driven movement. Pores nevertheless allow a high diffusive flux of more than 66 molecules per second that can also be directed beyond equillibria. The pores may be exploited to sense diagnostically relevant proteins with portable analysis technology, to create molecular gates for drug delivery, or to build synthetic cells.
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38
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Misawa N, Osaki T, Takeuchi S. Membrane protein-based biosensors. J R Soc Interface 2019; 15:rsif.2017.0952. [PMID: 29669891 DOI: 10.1098/rsif.2017.0952] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Accepted: 03/19/2018] [Indexed: 01/09/2023] Open
Abstract
This review highlights recent development of biosensors that use the functions of membrane proteins. Membrane proteins are essential components of biological membranes and have a central role in detection of various environmental stimuli such as olfaction and gustation. A number of studies have attempted for development of biosensors using the sensing property of these membrane proteins. Their specificity to target molecules is particularly attractive as it is significantly superior to that of traditional human-made sensors. In this review, we classified the membrane protein-based biosensors into two platforms: the lipid bilayer-based platform and the cell-based platform. On lipid bilayer platforms, the membrane proteins are embedded in a lipid bilayer that bridges between the protein and a sensor device. On cell-based platforms, the membrane proteins are expressed in a cultured cell, which is then integrated in a sensor device. For both platforms we introduce the fundamental information and the recent progress in the development of the biosensors, and remark on the outlook for practical biosensing applications.
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Affiliation(s)
- Nobuo Misawa
- Artificial Cell Membrane Systems Group, Kanagawa Institute of Industrial Science and Technology, 3-2-1 Sakado, Takatsu, Kawasaki 213-0012, Japan
| | - Toshihisa Osaki
- Artificial Cell Membrane Systems Group, Kanagawa Institute of Industrial Science and Technology, 3-2-1 Sakado, Takatsu, Kawasaki 213-0012, Japan.,Institute of Industrial Science, The University of Tokyo, 4-6-1 Komaba, Meguro, Tokyo 153-8505, Japan
| | - Shoji Takeuchi
- Artificial Cell Membrane Systems Group, Kanagawa Institute of Industrial Science and Technology, 3-2-1 Sakado, Takatsu, Kawasaki 213-0012, Japan .,Institute of Industrial Science, The University of Tokyo, 4-6-1 Komaba, Meguro, Tokyo 153-8505, Japan
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39
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Enhancement of membrane protein reconstitution on 3D free-standing lipid bilayer array in a microfluidic channel. Biosens Bioelectron 2019; 141:111404. [DOI: 10.1016/j.bios.2019.111404] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Revised: 05/24/2019] [Accepted: 06/01/2019] [Indexed: 12/11/2022]
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40
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Minagawa Y, Ueno H, Tabata KV, Noji H. Mobile imaging platform for digital influenza virus counting. LAB ON A CHIP 2019; 19:2678-2687. [PMID: 31312832 DOI: 10.1039/c9lc00370c] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Droplet-based digital bioassays enable highly sensitive and quantitative analysis of biomolecules, and are thought to be suitable for point-of-care diagnosis. However, digital bioassays generally require fluorescence microscopy for detection, which is too large for point-of-care testing. Here, we developed a simple smartphone-based mobile imaging platform for digital bioassays. The size of the mobile imaging platform was 23 × 10 × 7 cm (length × width × height). With this platform, a digital enzyme assay of bovine alkaline phosphatase was successfully completed. Digital influenza virus counting-based on a fluorogenic assay for neuraminidase activity of the virus-was also demonstrated. Distinct fluorescence spots derived from single virus particles were observed with the mobile imaging platform. The number of detected fluorescence spots showed good linearity against the virus titer, suggesting that high sensitivity and quantification were achieved, although the imaging with the mobile platform detected 60% of influenza virus particles that were identified with conventional fluorescence microscopy. The lower detection efficiency is due to its relatively lower signal-to-noise ratio than that found with conventional microscopes, and unavoidable intrinsic heterogeneity of neuraminidase activity among virus particles. Digital influenza virus counting with the mobile imaging platform still showed 100 times greater sensitivity than that with a commercial rapid influenza test kit. Virus detection of clinical samples was also successfully demonstrated, suggesting the potential to realize a highly sensitive point-of-care system for influenza virus detection with smartphones.
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Affiliation(s)
- Yoshihiro Minagawa
- Department of Applied Chemistry, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Japan.
| | - Hiroshi Ueno
- Department of Applied Chemistry, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Japan.
| | - Kazuhito V Tabata
- Department of Applied Chemistry, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Japan.
| | - Hiroyuki Noji
- Department of Applied Chemistry, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Japan.
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41
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Izri Z, Garenne D, Noireaux V, Maeda YT. Gene Expression in on-Chip Membrane-Bound Artificial Cells. ACS Synth Biol 2019; 8:1705-1712. [PMID: 31268305 DOI: 10.1021/acssynbio.9b00247] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Artificial cells made of molecular components and lipid membrane are emerging platforms to characterize living systems properties. Cell-free transcription-translation (TXTL) offers advantages for the bottom-up synthesis of cellular reactors. Yet, scaling up their design within well-defined geometries remains challenging. We present a microfluidic device hosting TXTL reactions of a reporter gene in thousands of microwells separated from an external buffer by a phospholipid membrane. In the presence of nutrients in the buffer, microreactors are stable beyond 24 h and yield a few mg/mL of proteins. Nutrients in the external solution feed the TXTL reaction at the picoliter scale via passive transport across the phospholipid membrane of each microfluidic well, despite the absence of pores. Replacing nutrients with an inert polymer and fatty acids at an isotonic concentration reduces microreactors efficiency, and a significant fraction yields no protein. This emphasizes the crucial role of the membrane for designing cell-free TXTL microreactors as efficient artificial cells.
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Affiliation(s)
- Ziane Izri
- Department of Physics , Kyushu University , Fukuoka , 819-0395 , Japan
| | - David Garenne
- School of Physics and Astronomy , University of Minnesota , Minneapolis , Minnesota 55455 United States
| | - Vincent Noireaux
- School of Physics and Astronomy , University of Minnesota , Minneapolis , Minnesota 55455 United States
| | - Yusuke T Maeda
- Department of Physics , Kyushu University , Fukuoka , 819-0395 , Japan
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42
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Eto H, Soga N, Franquelim HG, Glock P, Khmelinskaia A, Kai L, Heymann M, Noji H, Schwille P. Design of Sealable Custom-Shaped Cell Mimicries Based on Self-Assembled Monolayers on CYTOP Polymer. ACS APPLIED MATERIALS & INTERFACES 2019; 11:21372-21380. [PMID: 31136146 PMCID: PMC6750829 DOI: 10.1021/acsami.9b05073] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2019] [Accepted: 05/28/2019] [Indexed: 05/02/2023]
Abstract
In bottom-up synthetic biology, one of the major methodological challenges is to provide reaction spaces that mimic biological systems with regard to topology and surface functionality. Of particular interest are cell- or organelle-shaped membrane compartments, as many protein functions unfold at lipid interfaces. However, shaping artificial cell systems using materials with non-intrusive physicochemical properties, while maintaining flexible lipid interfaces relevant to the reconstituted protein systems, is not straightforward. Herein, we develop micropatterned chambers from CYTOP, a less commonly used polymer with good chemical resistance and a refractive index matching that of water. By forming a self-assembled lipid monolayer on the polymer surface, we dramatically increased the biocompatibility of CYTOP-fabricated systems. The phospholipid interface provides an excellent passivation layer to prevent protein adhesion to the hydrophobic surface, and we succeeded in cell-free protein synthesis inside the chambers. Importantly, the chambers could be sealed after loading by a lipid monolayer, providing a novel platform to study encapsulated systems. We successfully reconstituted pole-to-pole oscillations of the Escherichia coli MinDE system, which responds dramatically to compartment geometry. Furthermore, we present a simplified fabrication of our artificial cell compartments via replica molding, making it a readily accessible technique for standard cleanroom facilities.
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Affiliation(s)
- Hiromune Eto
- Max
Planck Institute of Biochemistry, Am Klopferspitz 18, D-82152 Martinsried, Germany
| | - Naoki Soga
- Department
of Applied Chemistry, Graduate School of Engineering, The University of Tokyo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Henri G. Franquelim
- Max
Planck Institute of Biochemistry, Am Klopferspitz 18, D-82152 Martinsried, Germany
| | - Philipp Glock
- Max
Planck Institute of Biochemistry, Am Klopferspitz 18, D-82152 Martinsried, Germany
| | - Alena Khmelinskaia
- Max
Planck Institute of Biochemistry, Am Klopferspitz 18, D-82152 Martinsried, Germany
- Institute
for Protein Design, University of Washington, Seattle 98195, Washington, United States
| | - Lei Kai
- Max
Planck Institute of Biochemistry, Am Klopferspitz 18, D-82152 Martinsried, Germany
- School
of Life Sciences, Jiangsu Normal University, Shanghai Road 101, 221116 Xuzhou, P. R. China
| | - Michael Heymann
- Max
Planck Institute of Biochemistry, Am Klopferspitz 18, D-82152 Martinsried, Germany
| | - Hiroyuki Noji
- Department
of Applied Chemistry, Graduate School of Engineering, The University of Tokyo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Petra Schwille
- Max
Planck Institute of Biochemistry, Am Klopferspitz 18, D-82152 Martinsried, Germany
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43
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Essential Role of the ε Subunit for Reversible Chemo-Mechanical Coupling in F 1-ATPase. Biophys J 2019; 114:178-187. [PMID: 29320685 DOI: 10.1016/j.bpj.2017.11.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Revised: 10/31/2017] [Accepted: 11/06/2017] [Indexed: 11/22/2022] Open
Abstract
F1-ATPase is a rotary motor protein driven by ATP hydrolysis. Among molecular motors, F1 exhibits unique high reversibility in chemo-mechanical coupling, synthesizing ATP from ADP and inorganic phosphate upon forcible rotor reversal. The ε subunit enhances ATP synthesis coupling efficiency to > 70% upon rotation reversal. However, the detailed mechanism has remained elusive. In this study, we performed stall-and-release experiments to elucidate how the ε subunit modulates ATP association/dissociation and hydrolysis/synthesis process kinetics and thermodynamics, key reaction steps for efficient ATP synthesis. The ε subunit significantly accelerated the rates of ATP dissociation and synthesis by two- to fivefold, whereas those of ATP binding and hydrolysis were not enhanced. Numerical analysis based on the determined kinetic parameters quantitatively reproduced previous findings of two- to fivefold coupling efficiency improvement by the ε subunit at the condition exhibiting the maximum ATP synthesis activity, a physiological role of F1-ATPase. Furthermore, fundamentally similar results were obtained upon ε subunit C-terminal domain truncation, suggesting that the N-terminal domain is responsible for the rate enhancement.
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44
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Muller MP, Jiang T, Sun C, Lihan M, Pant S, Mahinthichaichan P, Trifan A, Tajkhorshid E. Characterization of Lipid-Protein Interactions and Lipid-Mediated Modulation of Membrane Protein Function through Molecular Simulation. Chem Rev 2019; 119:6086-6161. [PMID: 30978005 PMCID: PMC6506392 DOI: 10.1021/acs.chemrev.8b00608] [Citation(s) in RCA: 133] [Impact Index Per Article: 26.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The cellular membrane constitutes one of the most fundamental compartments of a living cell, where key processes such as selective transport of material and exchange of information between the cell and its environment are mediated by proteins that are closely associated with the membrane. The heterogeneity of lipid composition of biological membranes and the effect of lipid molecules on the structure, dynamics, and function of membrane proteins are now widely recognized. Characterization of these functionally important lipid-protein interactions with experimental techniques is however still prohibitively challenging. Molecular dynamics (MD) simulations offer a powerful complementary approach with sufficient temporal and spatial resolutions to gain atomic-level structural information and energetics on lipid-protein interactions. In this review, we aim to provide a broad survey of MD simulations focusing on exploring lipid-protein interactions and characterizing lipid-modulated protein structure and dynamics that have been successful in providing novel insight into the mechanism of membrane protein function.
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Affiliation(s)
- Melanie P. Muller
- NIH Center for Macromolecular Modeling and Bioinformatics, Beckman Institute for Advanced Science and Technology
- Department of Biochemistry
- Center for Biophysics and Quantitative Biology
- College of Medicine
- University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Tao Jiang
- NIH Center for Macromolecular Modeling and Bioinformatics, Beckman Institute for Advanced Science and Technology
- Department of Biochemistry
- Center for Biophysics and Quantitative Biology
- University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Chang Sun
- NIH Center for Macromolecular Modeling and Bioinformatics, Beckman Institute for Advanced Science and Technology
- Department of Biochemistry
- University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Muyun Lihan
- NIH Center for Macromolecular Modeling and Bioinformatics, Beckman Institute for Advanced Science and Technology
- Department of Biochemistry
- Center for Biophysics and Quantitative Biology
- University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Shashank Pant
- NIH Center for Macromolecular Modeling and Bioinformatics, Beckman Institute for Advanced Science and Technology
- Department of Biochemistry
- Center for Biophysics and Quantitative Biology
- University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Paween Mahinthichaichan
- NIH Center for Macromolecular Modeling and Bioinformatics, Beckman Institute for Advanced Science and Technology
- Department of Biochemistry
- University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Anda Trifan
- NIH Center for Macromolecular Modeling and Bioinformatics, Beckman Institute for Advanced Science and Technology
- Department of Biochemistry
- Center for Biophysics and Quantitative Biology
- University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Emad Tajkhorshid
- NIH Center for Macromolecular Modeling and Bioinformatics, Beckman Institute for Advanced Science and Technology
- Department of Biochemistry
- Center for Biophysics and Quantitative Biology
- College of Medicine
- University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
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45
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Watanabe R. Microsystem for the single molecule analysis of membrane transport proteins. Biochim Biophys Acta Gen Subj 2019; 1864:129330. [PMID: 30926442 DOI: 10.1016/j.bbagen.2019.03.016] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2018] [Revised: 03/19/2019] [Accepted: 03/22/2019] [Indexed: 12/31/2022]
Abstract
Micro-chamber arrays enable highly sensitive and quantitative bioassays at the single-molecule level. Accordingly, they are widely used for ultra-sensitive biomedical applications, e.g., digital PCR and digital ELISA. However, the versatility of micro-chambers is generally limited to reactions in aqueous solutions, although various functions of membrane proteins are extremely important. To address this issue, microsystems using arrayed micro-sized chambers sealed with lipid bilayers, referred to here as a "biomembrane microsystems", have been developed by many research groups for the analysis of membrane proteins. In this review, I would like to introduce recent progress on the single molecule analysis of membrane transport proteins using a biomembrane microsystem, and discuss the future prospects for its use in analytical and pharmacological applications.
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Tabata KV, Minagawa Y, Kawaguchi Y, Ono M, Moriizumi Y, Yamayoshi S, Fujioka Y, Ohba Y, Kawaoka Y, Noji H. Antibody-free digital influenza virus counting based on neuraminidase activity. Sci Rep 2019; 9:1067. [PMID: 30705374 PMCID: PMC6355933 DOI: 10.1038/s41598-018-37994-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2018] [Accepted: 12/17/2018] [Indexed: 12/14/2022] Open
Abstract
There is large demand for a quantitative method for rapid and ultra-sensitive detection of the influenza virus. Here, we established a digital influenza virus counting (DIViC) method that can detect a single virion without antibody. In the assay, a virion is stochastically entrapped inside a femtoliter reactor array device for the fluorogenic assay of neuraminidase, and incubated for minutes. By analyzing 600,000 reactors, the practical limit of detection reached the order of 103 (PFU)/mL, only 10-times less sensitive than RT-PCR and more than 1000-times sensitive than commercial rapid test kits (RIDTs). Interestingly, neuraminidase activity differed among virions. The coefficient of variance was 30–40%, evidently broader than that of alkaline phosphatase measured as a model enzyme for comparison, suggesting the heterogeneity in size and integrity among influenza virus particles. Sensitivity to oseltamivir also differed between virions. We also tested DIViC using clinical gargle samples that imposes less burden for sampling while with less virus titre. The comparison with RIDTs showed that DIViC was largely superior to RIDTs in the sensitivity with the clinical samples although a few false-positive signals were observed in some clinical samples that remains as a technical challenge.
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Affiliation(s)
- Kazuhito V Tabata
- Department of Applied Chemistry, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Japan. .,ImPACT Program, Cabinet Office, Government of Japan, Chiyoda-ku, Tokyo, 100-8914, Japan.
| | - Yoshihiro Minagawa
- Department of Applied Chemistry, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Japan
| | - Yuko Kawaguchi
- Department of Applied Chemistry, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Japan
| | - Mana Ono
- Department of Applied Chemistry, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Japan
| | - Yoshiki Moriizumi
- Department of Applied Chemistry, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Japan
| | - Seiya Yamayoshi
- Division of Virology, Department of Microbiology and Immunology, Institute of Medical Science, University of Tokyo, Minato-ku, Tokyo, 108-8639, Japan
| | - Yoichiro Fujioka
- Department of Cell Physiology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, N15 W7, Kita-ku, Sapporo, Japan
| | - Yusuke Ohba
- Department of Cell Physiology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, N15 W7, Kita-ku, Sapporo, Japan
| | - Yoshihiro Kawaoka
- Division of Virology, Department of Microbiology and Immunology, Institute of Medical Science, University of Tokyo, Minato-ku, Tokyo, 108-8639, Japan.,Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, Wisconsin, 53711, USA
| | - Hiroyuki Noji
- Department of Applied Chemistry, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Japan. .,ImPACT Program, Cabinet Office, Government of Japan, Chiyoda-ku, Tokyo, 100-8914, Japan.
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47
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Ono T, Ichiki T, Noji H. Digital enzyme assay using attoliter droplet array. Analyst 2018; 143:4923-4929. [PMID: 30221644 PMCID: PMC6180314 DOI: 10.1039/c8an01152d] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Accepted: 08/18/2018] [Indexed: 01/12/2023]
Abstract
Single-molecule digital enzyme assay using micron-sized droplet array is a promising analysis method to quantify biomolecules at extremely low concentrations. However, multiplex digital enzyme assays are still difficult to access because the best buffer conditions can vary largely among enzymes. In addition, the best conditions for flurogenic compounds to retain high quantum efficiency and to avoid leakage into the oil phase can be also very different. In this study, digital enzyme assay was performed using an array of nanometer-sized droplets of 200 aL volume, termed 'nanocell'. Due to the small reaction volume, nanocell enhanced the accumulation rate of fluorescent products by a factor of 100 when compared with micron-sized reactors. Nanocell also enabled oil-free sealing of reactors: when flushed with an air flow, nanocell displayed water droplets under air, allowing enzymes to catalyze the reaction at the same rate as in oil-sealed reactors. Dual digital enzyme assay was also demonstrated using β-galactosidase and alkaline phosphatase (ALP) at pH 7.4, which is far from the optimum condition for ALP. Even under such a non-optimum condition, ALP molecules were successfully detected. Nanocell could largely expand the applicability of digital bioassay for enzymes under non-optimum conditions or enzymes of low turnover rate. The sealing of the reactor with air would also expand the applicability, allowing the use of fluorescent dyes that leak into oil.
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Affiliation(s)
- Takao Ono
- Department of Applied Chemistry
, Graduate School of Engineering
, The University of Tokyo
,
Japan
.
| | - Takanori Ichiki
- Department of Materials Engineering
, Graduate School of Engineering
, The University of Tokyo
,
Japan
| | - Hiroyuki Noji
- Department of Applied Chemistry
, Graduate School of Engineering
, The University of Tokyo
,
Japan
.
- ImPACT Program
, Japan Science and Technology Agency
,
Saitama 332-0012
, Japan
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48
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Watanabe R, Komatsu T, Sakamoto S, Urano Y, Noji H. High-throughput single-molecule bioassay using micro-reactor arrays with a concentration gradient of target molecules. LAB ON A CHIP 2018; 18:2849-2853. [PMID: 30091771 DOI: 10.1039/c8lc00535d] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Micro-reactor arrays enable highly sensitive and quantitative bioassays at a single-molecule level. Accordingly, they are widely used for sensitive "digital" bioassays, e.g., digital PCR and digital ELISA. Despite high integration, individual reactors in digital bioassays are filled with a uniform reaction solution, thus limiting the ability to simultaneously conduct multiple bioassays under different conditions using integrated reactors in parallel, resulting in the loss of potential throughput. We developed micro-reactor arrays with a concentration gradient of target molecules, in which individual reactors sealed with a lipid-bilayer membrane contained a precise amount of target molecules. Using the arrays, we successfully demonstrated multiple single-molecule bioassays in parallel using alkaline phosphatase or α-hemolysin, key components in various biomedical sensors. This new platform extends the versatility of micro-reactor arrays and could enable further analytical and pharmacological applications.
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Affiliation(s)
- Rikiya Watanabe
- Department of Applied Chemistry, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
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49
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Affiliation(s)
- Limor Cohen
- Department of Pathology, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts 02115, United States
| | - David R. Walt
- Department of Pathology, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts 02115, United States
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50
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Hybrid cell reactor system from Escherichia coli protoplast cells and arrayed lipid bilayer chamber device. Sci Rep 2018; 8:11757. [PMID: 30082826 PMCID: PMC6078950 DOI: 10.1038/s41598-018-30231-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Accepted: 07/25/2018] [Indexed: 11/09/2022] Open
Abstract
We developed a novel hybrid cell reactor system via functional fusion of single Escherichia coli protoplast cells, that are deficient in cell wall and expose plasma membrane, with arrayed lipid bilayer chambers on a device in order to incorporate the full set of cytosolic and membrane constituents into the artificial chambers. We investigated gene expression activity to represent the viability of the hybrid cell reactors: over 20% of hybrid cells showed gene expression activity from plasmid or mRNA. This suggests that the hybrid cell reactors retained fundamental activity of genetic information transduction. To expand the applicability of the hybrid cell reactors, we also developed the E. coli-in-E. coli cytoplasm system as an artificial parasitism system. Over 30% of encapsulated E. coli cells exhibited normal cell division, showing that hybrid cells can accommodate and cultivate living cells. This novel artificial cell reactor technology would enable unique approaches for synthetic cell researches such as reconstruction of living cell, artificial parasitism/symbiosis system, or physical simulation to test functionality of synthetic genome.
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