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Bickley CD, Wan J, Komeili A. Intrinsic and extrinsic determinants of conditional localization of Mms6 to magnetosome organelles in Magnetospirillum magneticum AMB-1. J Bacteriol 2024; 206:e0000824. [PMID: 38819153 PMCID: PMC11332177 DOI: 10.1128/jb.00008-24] [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: 01/05/2024] [Accepted: 03/28/2024] [Indexed: 06/01/2024] Open
Abstract
Magnetotactic bacteria are a diverse group of microbes that use magnetic particles housed within intracellular lipid-bounded magnetosome organelles to guide navigation along geomagnetic fields. The development of magnetosomes and their magnetic crystals in Magnetospirillum magneticum AMB-1 requires the coordinated action of numerous proteins. Most proteins are thought to localize to magnetosomes during the initial stages of organelle biogenesis, regardless of environmental conditions. However, the magnetite-shaping protein Mms6 is only found in magnetosomes that contain magnetic particles, suggesting that it might conditionally localize after the formation of magnetosome membranes. The mechanisms for this unusual mode of localization to magnetosomes are unclear. Here, using pulse-chase labeling, we show that Mms6 translated under non-biomineralization conditions translocates to pre-formed magnetosomes when cells are shifted to biomineralizing conditions. Genes essential for magnetite production, namely mamE, mamM, and mamO, are necessary for Mms6 localization, whereas mamN inhibits Mms6 localization. MamD localization was also investigated and found to be controlled by similar cellular factors. The membrane localization of Mms6 is dependent on a glycine-leucine repeat region, while the N-terminal domain of Mms6 is necessary for retention in the cytosol and impacts conditional localization to magnetosomes. The N-terminal domain is also sufficient to impart conditional magnetosome localization to MmsF, altering its native constitutive magnetosome localization. Our work illuminates an alternative mode of protein localization to magnetosomes in which Mms6 and MamD are excluded from magnetosomes by MamN until biomineralization initiates, whereupon they translocate into magnetosome membranes to control the development of growing magnetite crystals.IMPORTANCEMagnetotactic bacteria (MTB) are a diverse group of bacteria that form magnetic nanoparticles surrounded by membranous organelles. MTB are widespread and serve as a model for bacterial organelle formation and biomineralization. Magnetosomes require a specific cohort of proteins to enable magnetite formation, but how those proteins are localized to magnetosome membranes is unclear. Here, we investigate protein localization using pulse-chase microscopy and find a system of protein coordination dependent on biomineralization-permissible conditions. In addition, our findings highlight a protein domain that alters the localization behavior of magnetosome proteins. Utilization of this protein domain may provide a synthetic route for conditional functionalization of magnetosomes for biotechnological applications.
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Affiliation(s)
- Carson D. Bickley
- Department of Plant and Microbial Biology, University of California, Berkeley, California, USA
| | - Juan Wan
- Key Laboratory of Earth and Planetary Physics, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing, China
| | - Arash Komeili
- Department of Plant and Microbial Biology, University of California, Berkeley, California, USA
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Abdelhamid MAA, Ki MR, Pack SP. Biominerals and Bioinspired Materials in Biosensing: Recent Advancements and Applications. Int J Mol Sci 2024; 25:4678. [PMID: 38731897 PMCID: PMC11083057 DOI: 10.3390/ijms25094678] [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: 03/25/2024] [Revised: 04/18/2024] [Accepted: 04/19/2024] [Indexed: 05/13/2024] Open
Abstract
Inspired by nature's remarkable ability to form intricate minerals, researchers have unlocked transformative strategies for creating next-generation biosensors with exceptional sensitivity, selectivity, and biocompatibility. By mimicking how organisms orchestrate mineral growth, biomimetic and bioinspired materials are significantly impacting biosensor design. Engineered bioinspired materials offer distinct advantages over their natural counterparts, boasting superior tunability, precise controllability, and the ability to integrate specific functionalities for enhanced sensing capabilities. This remarkable versatility enables the construction of various biosensing platforms, including optical sensors, electrochemical sensors, magnetic biosensors, and nucleic acid detection platforms, for diverse applications. Additionally, bioinspired materials facilitate the development of smartphone-assisted biosensing platforms, offering user-friendly and portable diagnostic tools for point-of-care applications. This review comprehensively explores the utilization of naturally occurring and engineered biominerals and materials for diverse biosensing applications. We highlight the fabrication and design strategies that tailor their functionalities to address specific biosensing needs. This in-depth exploration underscores the transformative potential of biominerals and materials in revolutionizing biosensing, paving the way for advancements in healthcare, environmental monitoring, and other critical fields.
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Affiliation(s)
- Mohamed A. A. Abdelhamid
- Department of Biotechnology and Bioinformatics, Korea University, Sejong-ro 2511, Sejong 30019, Republic of Korea; (M.A.A.A.); (M.-R.K.)
- Department of Botany and Microbiology, Faculty of Science, Minia University, Minia 61519, Egypt
| | - Mi-Ran Ki
- Department of Biotechnology and Bioinformatics, Korea University, Sejong-ro 2511, Sejong 30019, Republic of Korea; (M.A.A.A.); (M.-R.K.)
- Institute of Industrial Technology, Korea University, Sejong-ro 2511, Sejong 30019, Republic of Korea
| | - Seung Pil Pack
- Department of Biotechnology and Bioinformatics, Korea University, Sejong-ro 2511, Sejong 30019, Republic of Korea; (M.A.A.A.); (M.-R.K.)
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3
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Qi D, Lukić MJ, Lu H, Gebauer D, Bonn M. Role of Water during the Early Stages of Iron Oxyhydroxide Formation by a Bacterial Iron Nucleator. J Phys Chem Lett 2024; 15:1048-1055. [PMID: 38253017 DOI: 10.1021/acs.jpclett.3c03327] [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: 01/24/2024]
Abstract
Understanding the nucleation of iron oxides and the underlying hydrolysis of aqueous iron species is still challenging, and molecular-level insights into the orchestrated response of water, especially at the hydrolysis interface, are lacking. We follow iron(III) hydrolysis in the presence of a synthetic bacterial iron nucleator, which is a magnetosome membrane specific peptide, by using a constant pH titration technique. Three distinct hydrolysis regimes were identified. Interface-selective sum frequency generation (SFG) spectroscopy was used to probe the interfacial reaction and water in direct contact with the peptide. SFG data reveal that iron(III) species react quickly with interfacial peptides while continuously enhancing water alignment into the later stages of hydrolysis. The gradually aligning water molecules are associated with initially promoted (regimes I and II) and later suppressed (regime III) hydrolysis after the saturation of water alignment has occurred until regime II. These interfacial insights are crucial for understanding the early stage of iron oxide biomineralization.
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Affiliation(s)
- Daizong Qi
- Department of Materials and Textile Engineering, Nanotechnology Research Institute, Jiaxing University, Building No. 7, Jiaxing Intelligent Industry & Innovation Park, Jiaxing, Zhejiang 314001, P. R. China
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Miodrag J Lukić
- Institute of Inorganic Chemistry, Leibniz University Hannover, Callinstrasse 9, 30167 Hannover, Germany
| | - Hao Lu
- Department of Materials and Textile Engineering, Nanotechnology Research Institute, Jiaxing University, Building No. 7, Jiaxing Intelligent Industry & Innovation Park, Jiaxing, Zhejiang 314001, P. R. China
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Denis Gebauer
- Institute of Inorganic Chemistry, Leibniz University Hannover, Callinstrasse 9, 30167 Hannover, Germany
| | - Mischa Bonn
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
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4
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Obozina AS, Komedchikova EN, Kolesnikova OA, Iureva AM, Kovalenko VL, Zavalko FA, Rozhnikova TV, Tereshina ED, Mochalova EN, Shipunova VO. Genetically Encoded Self-Assembling Protein Nanoparticles for the Targeted Delivery In Vitro and In Vivo. Pharmaceutics 2023; 15:231. [PMID: 36678860 PMCID: PMC9861179 DOI: 10.3390/pharmaceutics15010231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Revised: 12/30/2022] [Accepted: 01/05/2023] [Indexed: 01/13/2023] Open
Abstract
Targeted nanoparticles of different origins are considered as new-generation diagnostic and therapeutic tools. However, there are no targeted drug formulations within the composition of nanoparticles approved by the FDA for use in the clinic, which is associated with the insufficient effectiveness of the developed candidates, the difficulties of their biotechnological production, and inadequate batch-to-batch reproducibility. Targeted protein self-assembling nanoparticles circumvent this problem since proteins are encoded in DNA and the final protein product is produced in only one possible way. We believe that the combination of the endless biomedical potential of protein carriers as nanoparticles and the standardized protein purification protocols will make significant progress in "magic bullet" creation possible, bringing modern biomedicine to a new level. In this review, we are focused on the currently existing platforms for targeted self-assembling protein nanoparticles based on transferrin, lactoferrin, casein, lumazine synthase, albumin, ferritin, and encapsulin proteins, as well as on proteins from magnetosomes and virus-like particles. The applications of these self-assembling proteins for targeted delivery in vitro and in vivo are thoroughly discussed, including bioimaging applications and different therapeutic approaches, such as chemotherapy, gene delivery, and photodynamic and photothermal therapy. A critical assessment of these protein platforms' efficacy in biomedicine is provided and possible problems associated with their further development are described.
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Affiliation(s)
| | | | | | - Anna M. Iureva
- Moscow Institute of Physics and Technology, 141701 Dolgoprudny, Russia
| | - Vera L. Kovalenko
- Moscow Institute of Physics and Technology, 141701 Dolgoprudny, Russia
| | - Fedor A. Zavalko
- Moscow Institute of Physics and Technology, 141701 Dolgoprudny, Russia
| | | | | | - Elizaveta N. Mochalova
- Moscow Institute of Physics and Technology, 141701 Dolgoprudny, Russia
- Nanobiomedicine Division, Sirius University of Science and Technology, 354340 Sochi, Russia
| | - Victoria O. Shipunova
- Moscow Institute of Physics and Technology, 141701 Dolgoprudny, Russia
- Nanobiomedicine Division, Sirius University of Science and Technology, 354340 Sochi, Russia
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5
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Aires A, Fernández-Afonso Y, Guedes G, Guisasola E, Gutiérrez L, Cortajarena AL. Engineered Protein-Driven Synthesis of Tunable Iron Oxide Nanoparticles as T1 and T2 Magnetic Resonance Imaging Contrast Agents. CHEMISTRY OF MATERIALS : A PUBLICATION OF THE AMERICAN CHEMICAL SOCIETY 2022; 34:10832-10841. [PMID: 36590706 PMCID: PMC9798829 DOI: 10.1021/acs.chemmater.2c01746] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2022] [Revised: 11/15/2022] [Indexed: 05/14/2023]
Abstract
Iron oxide nanoparticles (IONPs) have become one of the most promising nanomaterials for biomedical applications because of their biocompatibility and physicochemical properties. This study demonstrates the use of protein engineering as a novel approach to design scaffolds for the tunable synthesis of ultrasmall IONPs. Rationally designed proteins, containing different number of metal-coordination sites, were evaluated to control the size and the physicochemical and magnetic properties of a set of protein-stabilized IONPs (Prot-IONPs). Prot-IONPs, synthesized through an optimized coprecipitation approach, presented good T1 and T2 relaxivity values, stability, and biocompatibility, showing potential for magnetic resonance imaging (MRI) applications.
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Affiliation(s)
- Antonio Aires
- Center
for Cooperative Research in Biomaterials (CIC biomaGUNE), Basque Research and Technology Alliance (BRTA), Paseo de Miramón 194, Donostia-San Sebastián 20014, Spain
| | - Yilian Fernández-Afonso
- Instituto
de Nanociencia y Materiales de Aragón (INMA), CSIC-Universidad de Zaragoza, 50018 Zaragoza, Spain
| | - Gabriela Guedes
- Center
for Cooperative Research in Biomaterials (CIC biomaGUNE), Basque Research and Technology Alliance (BRTA), Paseo de Miramón 194, Donostia-San Sebastián 20014, Spain
- University
of the Basque Country (UPV/EHU), 48940 Leioa, Spain
| | - Eduardo Guisasola
- Center
for Cooperative Research in Biomaterials (CIC biomaGUNE), Basque Research and Technology Alliance (BRTA), Paseo de Miramón 194, Donostia-San Sebastián 20014, Spain
| | - Lucía Gutiérrez
- Instituto
de Nanociencia y Materiales de Aragón (INMA), CSIC-Universidad de Zaragoza, 50018 Zaragoza, Spain
- Centro
de Investigación Biomédica en Red de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), 50018 Zaragoza, Spain
| | - Aitziber L. Cortajarena
- Center
for Cooperative Research in Biomaterials (CIC biomaGUNE), Basque Research and Technology Alliance (BRTA), Paseo de Miramón 194, Donostia-San Sebastián 20014, Spain
- Ikerbasque, Basque Foundation for Science, 48009 Bilbao, Spain
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6
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Besenhard MO, Pal S, Storozhuk L, Dawes S, Thanh NTK, Norfolk L, Staniland S, Gavriilidis A. A versatile non-fouling multi-step flow reactor platform: demonstration for partial oxidation synthesis of iron oxide nanoparticles. LAB ON A CHIP 2022; 23:115-124. [PMID: 36454245 DOI: 10.1039/d2lc00892k] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
In the last decade flow reactors for material synthesis were firmly established, demonstrating advantageous operating conditions, reproducible and scalable production via continuous operation, as well as high-throughput screening of synthetic conditions. Reactor fouling, however, often restricts flow chemistry and the common fouling prevention via segmented flow comes at the cost of inflexibility. Often, the difficulty of feeding reagents into liquid segments (droplets or slugs) constrains flow syntheses using segmented flow to simple synthetic protocols with a single reagent addition step prior or during segmentation. Hence, the translation of fouling prone syntheses requiring multiple reagent addition steps into flow remains challenging. This work presents a modular flow reactor platform overcoming this bottleneck by fully exploiting the potential of three-phase (gas-liquid-liquid) segmented flow to supply reagents after segmentation, hence facilitating fouling free multi-step flow syntheses. The reactor design and materials selection address the operation challenges inherent to gas-liquid-liquid flow and reagent addition into segments allowing for a wide range of flow rates, flow ratios, temperatures, and use of continuous phases (no perfluorinated solvents needed). This "Lego®-like" reactor platform comprises elements for three-phase segmentation and sequential reagent addition into fluid segments, as well as temperature-controlled residence time modules that offer the flexibility required to translate even complex nanomaterial synthesis protocols to flow. To demonstrate the platform's versatility, we chose a fouling prone multi-step synthesis, i.e., a water-based partial oxidation synthesis of iron oxide nanoparticles. This synthesis required I) the precipitation of ferrous hydroxides, II) the addition of an oxidation agent, III) a temperature treatment to initiate magnetite/maghemite formation, and IV) the addition of citric acid to increase the colloidal stability. The platform facilitated the synthesis of colloidally stable magnetic nanoparticles reproducibly at well-controlled synthetic conditions and prevented fouling using heptane as continuous phase. The biocompatible particles showed excellent heating abilities in alternating magnetic fields (ILP values >3 nH m2 kgFe-1), hence, their potential for magnetic hyperthermia cancer treatment. The platform allowed for long term operation, as well as screening of synthetic conditions to tune particle properties. This was demonstrated via the addition of tetraethylenepentamine, confirming its potential to control particle morphology. Such a versatile reactor platform makes it possible to translate even complex syntheses into flow, opening up new opportunities for material synthesis.
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Affiliation(s)
- Maximilian O Besenhard
- Department of Chemical Engineering, University College London, Torrington Place, London, WC1E 7JE, UK.
| | - Sayan Pal
- Department of Chemical Engineering, University College London, Torrington Place, London, WC1E 7JE, UK.
| | - Liudmyla Storozhuk
- Biophysics Group, Department of Physics and Astronomy, University College London, Gower Street, London, WC1E 6BT, UK
| | - Simon Dawes
- Department of Chemical Engineering, University College London, Torrington Place, London, WC1E 7JE, UK.
| | - Nguyen Thi Kim Thanh
- Biophysics Group, Department of Physics and Astronomy, University College London, Gower Street, London, WC1E 6BT, UK
- UCL Healthcare Biomagnetics and Nanomaterials Laboratories, University College London, 21 Albemarle Street, London W1S 4BS, UK
| | - Laura Norfolk
- Department of Chemistry, The University of Sheffield, Dainton Building, Brook Hill, Sheffield, S3 7HF, UK
| | - Sarah Staniland
- Department of Chemistry, The University of Sheffield, Dainton Building, Brook Hill, Sheffield, S3 7HF, UK
| | - Asterios Gavriilidis
- Department of Chemical Engineering, University College London, Torrington Place, London, WC1E 7JE, UK.
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7
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Wei NL, Xu W, Tang HL, Xie Q, Zhai Y, Chen J, Zhang XY, Zhu JH. Learning from magnetotactic bacteria: mms6 protects stem cells from oxidative damage. Front Cell Neurosci 2022; 16:1075640. [PMID: 36505515 PMCID: PMC9728029 DOI: 10.3389/fncel.2022.1075640] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Accepted: 11/02/2022] [Indexed: 11/24/2022] Open
Abstract
Oxidative damage generally exists in stroke and impairs stem cells' survival; however, the problem is difficult to treat. In order to help stem cells to resist this damage, we inserted a magnetotactic bacteria (MB) gene, mms6, into the neural stem cell genome by lentiviral transfection. It was found that the transfection of mms6 significantly improved the survival rate of stem cells in the condition of iron overload but not hypoxia. The bioenergetic profile also revealed that iron overloading weakened the mitochondrial respiration and spare respiration capacity of stem cells, but that these were enhanced after the expression of mms6. Additionally, Western blotting (WB) data revealed that mms6 upregulated the expression of glutathione peroxidase (GPX4), which protected stem cells from oxidative damage and ferroptosis. In order to determine the possible mechanisms, we analyzed the interactions between the MMS6 protein, Fe2+, and GPX4 via analog computation. The predicted models found that the MMS6 protein had a direct chelating site in the region of M6A with divalent iron; it also had weak binding with GPX4. Taken together, the magnetotactic bacterial gene mms6 protected stem cells from oxidative damage via binding with Fe2+, which could help them adapt to the microenvironment of stroke.
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Affiliation(s)
- Nai-Li Wei
- Department of Neurosurgery, The First Affiliated Hospital of Shantou University Medical College, Shantou, Guangdong, China
- State Key Laboratory for Medical Neurobiology, Department of Neurosurgery, Institutes of Brain Science, Fudan University Huashan Hospital, Shanghai Medical College-Fudan University, Shanghai, China
| | - Wenjing Xu
- Institute of Science and Technology for Brain-Inspired Intelligence, Fudan University, Shanghai, China
- MOE Key Laboratory of Computational Neuroscience and Brain-Inspired Intelligence, MOE Frontiers Center for Brain Science, Fudan University, Shanghai, China
| | - Hai-Liang Tang
- State Key Laboratory for Medical Neurobiology, Department of Neurosurgery, Institutes of Brain Science, Fudan University Huashan Hospital, Shanghai Medical College-Fudan University, Shanghai, China
| | - Qiang Xie
- Department of Neurosurgery, Fudan University Zhongshan Hospital, Shanghai Medical College of Fudan University, Shanghai, China
| | - Yuting Zhai
- Institute of Science and Technology for Brain-Inspired Intelligence, Fudan University, Shanghai, China
- MOE Key Laboratory of Computational Neuroscience and Brain-Inspired Intelligence, MOE Frontiers Center for Brain Science, Fudan University, Shanghai, China
| | - Jian Chen
- Department of Neurosurgery, The First Affiliated Hospital of Shantou University Medical College, Shantou, Guangdong, China
| | - Xiao-Yong Zhang
- Institute of Science and Technology for Brain-Inspired Intelligence, Fudan University, Shanghai, China
- MOE Key Laboratory of Computational Neuroscience and Brain-Inspired Intelligence, MOE Frontiers Center for Brain Science, Fudan University, Shanghai, China
| | - Jian-Hong Zhu
- State Key Laboratory for Medical Neurobiology, Department of Neurosurgery, Institutes of Brain Science, Fudan University Huashan Hospital, Shanghai Medical College-Fudan University, Shanghai, China
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Ma K, Xu S, Tao T, Qian J, Cui Q, Rehman SU, Zhu X, Chen R, Zhao H, Wang C, Qi Z, Dai H, Zhang X, Xie C, Lu Y, Wang H, Wang J. Magnetosome-inspired synthesis of soft ferrimagnetic nanoparticles for magnetic tumor targeting. Proc Natl Acad Sci U S A 2022; 119:e2211228119. [PMID: 36322742 PMCID: PMC9659412 DOI: 10.1073/pnas.2211228119] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Accepted: 10/05/2022] [Indexed: 07/25/2023] Open
Abstract
Magnetic targeting is one of the most promising approaches for improving the targeting efficiency by which magnetic drug carriers are directed using external magnetic fields to reach their targets. As a natural magnetic nanoparticle (MNP) of biological origin, the magnetosome is a special "organelle" formed by biomineralization in magnetotactic bacteria (MTB) and is essential for MTB magnetic navigation to respond to geomagnetic fields. The magnetic targeting of magnetosomes, however, can be hindered by the aggregation and precipitation of magnetosomes in water and biological fluid environments due to the strong magnetic attraction between particles. In this study, we constructed a magnetosome-like nanoreactor by introducing MTB Mms6 protein into a reverse micelle system. MNPs synthesized by thermal decomposition exhibit the same crystal morphology and magnetism (high saturation magnetization and low coercivity) as natural magnetosomes but have a smaller particle size. The DSPE-mPEG-coated magnetosome-like MNPs exhibit good monodispersion, penetrating the lesion area of a tumor mouse model to achieve magnetic enrichment by an order of magnitude more than in the control groups, demonstrating great prospects for biomedical magnetic targeting applications.
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Affiliation(s)
- Kun Ma
- High Magnetic Field Laboratory, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, P. R. China
| | - Shuai Xu
- High Magnetic Field Laboratory, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, P. R. China
- University of Science and Technology of China, Hefei 230036, P. R. China
- Hefei Cancer Hospital, Anhui Province Key Laboratory of Medical Physics and Technology, Institute of Health and Medical Technology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, P. R. China
| | - Tongxiang Tao
- High Magnetic Field Laboratory, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, P. R. China
- University of Science and Technology of China, Hefei 230036, P. R. China
| | - Junchao Qian
- Hefei Cancer Hospital, Anhui Province Key Laboratory of Medical Physics and Technology, Institute of Health and Medical Technology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, P. R. China
- Department of Radiation Oncology, School of Medicine, Shandong University, Shandong Cancer Hospital and Institute, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan 250117, Shandong, P. R. China
| | - Qiqi Cui
- High Magnetic Field Laboratory, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, P. R. China
| | - Sajid ur Rehman
- High Magnetic Field Laboratory, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, P. R. China
| | - Xiaoguang Zhu
- Key Laboratory of Materials Physics, Institute of Solid State Physics, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, P. R. China
| | - Ruiguo Chen
- High Magnetic Field Laboratory, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, P. R. China
| | - Hongxin Zhao
- High Magnetic Field Laboratory, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, P. R. China
| | - Changhao Wang
- High Magnetic Field Laboratory, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, P. R. China
- University of Science and Technology of China, Hefei 230036, P. R. China
| | - Ziping Qi
- Hefei Cancer Hospital, Anhui Province Key Laboratory of Medical Physics and Technology, Institute of Health and Medical Technology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, P. R. China
| | - Han Dai
- High Magnetic Field Laboratory, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, P. R. China
| | - Xin Zhang
- High Magnetic Field Laboratory, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, P. R. China
- University of Science and Technology of China, Hefei 230036, P. R. China
- Institutes of Physical Science and Information Technology, Anhui University, Hefei 230601, P. R. China
| | - Can Xie
- High Magnetic Field Laboratory, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, P. R. China
- University of Science and Technology of China, Hefei 230036, P. R. China
- Institutes of Physical Science and Information Technology, Anhui University, Hefei 230601, P. R. China
| | - Yang Lu
- School of Chemistry and Chemical Engineering, Hefei University of Technology, Hefei 230009, P. R. China
| | - Hongzhi Wang
- Hefei Cancer Hospital, Anhui Province Key Laboratory of Medical Physics and Technology, Institute of Health and Medical Technology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, P. R. China
| | - Junfeng Wang
- High Magnetic Field Laboratory, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, P. R. China
- University of Science and Technology of China, Hefei 230036, P. R. China
- Institutes of Physical Science and Information Technology, Anhui University, Hefei 230601, P. R. China
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9
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The Magnetosome Protein, Mms6 from Magnetospirillum magneticum Strain AMB-1, Is a Lipid-Activated Ferric Reductase. Int J Mol Sci 2022; 23:ijms231810305. [PMID: 36142217 PMCID: PMC9499114 DOI: 10.3390/ijms231810305] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2022] [Revised: 09/02/2022] [Accepted: 09/03/2022] [Indexed: 11/26/2022] Open
Abstract
Magnetosomes of magnetotactic bacteria consist of magnetic nanocrystals with defined morphologies enclosed in vesicles originated from cytoplasmic membrane invaginations. Although many proteins are involved in creating magnetosomes, a single magnetosome protein, Mms6 from Magnetospirillum magneticum strain AMB-1, can direct the crystallization of magnetite nanoparticles in vitro. The in vivo role of Mms6 in magnetosome formation is debated, and the observation that Mms6 binds Fe3+ more tightly than Fe2+ raises the question of how, in a magnetosome environment dominated by Fe3+, Mms6 promotes the crystallization of magnetite, which contains both Fe3+ and Fe2+. Here we show that Mms6 is a ferric reductase that reduces Fe3+ to Fe2+ using NADH and FAD as electron donor and cofactor, respectively. Reductase activity is elevated when Mms6 is integrated into either liposomes or bicelles. Analysis of Mms6 mutants suggests that the C-terminal domain binds iron and the N-terminal domain contains the catalytic site. Although Mms6 forms multimers that involve C-terminal and N-terminal domain interactions, a fusion protein with ubiquitin remains a monomer and displays reductase activity, which suggests that the catalytic site is fully in the monomer. However, the quaternary structure of Mms6 appears to alter the iron binding characteristics of the C-terminal domain. These results are consistent with a hypothesis that Mms6, a membrane protein, promotes the formation of magnetite in vivo by a mechanism that involves reducing iron.
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10
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Hill LK, Britton D, Jihad T, Punia K, Xie X, Delgado-Fukushima E, Liu CF, Mishkit O, Liu C, Hu C, Meleties M, Renfrew PD, Bonneau R, Wadghiri YZ, Montclare JK. Engineered Protein-Iron Oxide Hybrid Biomaterial for MRI-traceable Drug Encapsulation. MOLECULAR SYSTEMS DESIGN & ENGINEERING 2022; 7:915-932. [PMID: 37274761 PMCID: PMC10237276 DOI: 10.1039/d2me00002d] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Labeled protein-based biomaterials have become a popular for various biomedical applications such as tissue-engineered, therapeutic, or diagnostic scaffolds. Labeling of protein biomaterials, including with ultrasmall super-paramagnetic iron oxide (USPIO) nanoparticles, has enabled a wide variety of imaging techniques. These USPIO-based biomaterials are widely studied in magnetic resonance imaging (MRI), thermotherapy, and magnetically-driven drug delivery which provide a method for direct and non-invasive monitoring of implants or drug delivery agents. Where most developments have been made using polymers or collagen hydrogels, shown here is the use of a rationally designed protein as the building block for a meso-scale fiber. While USPIOs have been chemically conjugated to antibodies, glycoproteins, and tissue-engineered scaffolds for targeting or improved biocompatibility and stability, these constructs have predominantly served as diagnostic agents and often involve harsh conditions for USPIO synthesis. Here, we present an engineered protein-iron oxide hybrid material comprised of an azide-functionalized coiled-coil protein with small molecule binding capacity conjugated via bioorthogonal azide-alkyne cycloaddition to an alkyne-bearing iron oxide templating peptide, CMms6, for USPIO biomineralization under mild conditions. The coiled-coil protein, dubbed Q, has been previously shown to form nanofibers and, upon small molecule binding, further assembles into mesofibers via encapsulation and aggregation. The resulting hybrid material is capable of doxorubicin encapsulation as well as sensitive T2*-weighted MRI darkening for strong imaging capability that is uniquely derived from a coiled-coil protein.
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Affiliation(s)
- Lindsay K. Hill
- Department of Chemical and Biomolecular Engineering, New York University Tandon School of Engineering, Brooklyn, New York, 11201, USA
- Department of Biomedical Engineering, SUNY Downstate Medical Center, Brooklyn, New York, 11203, USA
- Center for Advanced Imaging Innovation and Research (CAIR), New York University School of Medicine, New York, New York, 10016, USA
- Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology, New York University School of Medicine, New York, New York, 10016, USA
| | - Dustin Britton
- Department of Chemical and Biomolecular Engineering, New York University Tandon School of Engineering, Brooklyn, New York, 11201, USA
| | - Teeba Jihad
- Department of Chemical and Biomolecular Engineering, New York University Tandon School of Engineering, Brooklyn, New York, 11201, USA
| | - Kamia Punia
- Department of Chemical and Biomolecular Engineering, New York University Tandon School of Engineering, Brooklyn, New York, 11201, USA
| | - Xuan Xie
- Department of Chemical and Biomolecular Engineering, New York University Tandon School of Engineering, Brooklyn, New York, 11201, USA
| | - Erika Delgado-Fukushima
- Department of Chemical and Biomolecular Engineering, New York University Tandon School of Engineering, Brooklyn, New York, 11201, USA
| | - Che Fu Liu
- Department of Chemical and Biomolecular Engineering, New York University Tandon School of Engineering, Brooklyn, New York, 11201, USA
| | - Orin Mishkit
- Center for Advanced Imaging Innovation and Research (CAIR), New York University School of Medicine, New York, New York, 10016, USA
- Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology, New York University School of Medicine, New York, New York, 10016, USA
| | - Chengliang Liu
- Department of Chemical and Biomolecular Engineering, New York University Tandon School of Engineering, Brooklyn, New York, 11201, USA
| | - Chunhua Hu
- Department of Chemistry, New York University, New York, New York, 10012, USA
| | - Michael Meleties
- Department of Chemical and Biomolecular Engineering, New York University Tandon School of Engineering, Brooklyn, New York, 11201, USA
| | - P. Douglas Renfrew
- Center for Computational Biology, Flatiron Institute, Simons Foundation, New York, New York, 10010, USA
| | - Richard Bonneau
- Center for Computational Biology, Flatiron Institute, Simons Foundation, New York, New York, 10010, USA
- Center for Genomics and Systems Biology, New York University, New York, New York, 10003, USA
- Courant Institute of Mathematical Sciences, Computer Science Department, New York University, New York, New York, 10009, USA
| | - Youssef Z. Wadghiri
- Center for Advanced Imaging Innovation and Research (CAIR), New York University School of Medicine, New York, New York, 10016, USA
- Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology, New York University School of Medicine, New York, New York, 10016, USA
| | - Jin Kim Montclare
- Department of Chemical and Biomolecular Engineering, New York University Tandon School of Engineering, Brooklyn, New York, 11201, USA
- Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology, New York University School of Medicine, New York, New York, 10016, USA
- Department of Chemistry, New York University, New York, New York, 10012, USA
- Department of Biomaterials, New York University College of Dentistry, New York, New York, 10010, USA
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11
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Yavuz M, Ütkür M, Kehribar EŞ, Yağız E, Sarıtaş EÜ, Şeker UÖŞ. Engineered Bacteria with Genetic Circuits Accumulating Nanomagnets as MRI Contrast Agents. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2022; 18:e2200537. [PMID: 35567331 DOI: 10.1002/smll.202200537] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Revised: 04/23/2022] [Indexed: 06/15/2023]
Abstract
The demand for highly efficient cancer diagnostic tools increases alongside the high cancer incidence nowadays. Moreover, there is an imperative need for novel cancer treatment therapies that lack the side effects of conventional treatment options. Developments in this aspect employ magnetic nanoparticles (MNPs) for biomedical applications due to their stability, biocompatibility, and magnetic properties. Certain organisms, including many bacteria, can synthesize magnetic nanocrystals, which help their spatial orientation and survival by sensing the earth's geomagnetic field. This work aims to convert Escherichia coli to accumulate magnetite, which can further be coupled with drug delivery modules. The authors design magnetite accumulating bacterial machines using genetic circuitries hiring Mms6 with iron-binding activity and essential in magnetite crystal formation. The work demonstrates that the combinatorial effect of Mms6 with ferroxidase, iron transporter protein, and material binding peptide enhances the paramagnetic behavior of the cells in magnetic resonance imaging (MRI) measurements. Cellular machines are also engineered to display Mms6 peptide on the cell surface via an autotransporter protein that shows augmented MRI performance. The findings are promising for endowing a probiotic bacterium, able to accumulate magnetite intracellularly or extracellularly, serving as a theranostics agent for cancer diagnostics via MRI scanning and hyperthermia treatment.
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Affiliation(s)
- Merve Yavuz
- UNAM- Institute of Materials Science and Nanotechnology, National Nanotechnology Research Center, Bilkent University, Ankara, 06800, Turkey
| | - Mustafa Ütkür
- Department of Electrical and Electronics Engineering, Bilkent University, Ankara, 06800, Turkey
- National Magnetic Resonance Research Center (UMRAM), Bilkent University, Ankara, 06800, Turkey
| | - Ebru Şahin Kehribar
- UNAM- Institute of Materials Science and Nanotechnology, National Nanotechnology Research Center, Bilkent University, Ankara, 06800, Turkey
| | - Ecrin Yağız
- Department of Electrical and Electronics Engineering, Bilkent University, Ankara, 06800, Turkey
- National Magnetic Resonance Research Center (UMRAM), Bilkent University, Ankara, 06800, Turkey
| | - Emine Ülkü Sarıtaş
- Department of Electrical and Electronics Engineering, Bilkent University, Ankara, 06800, Turkey
- National Magnetic Resonance Research Center (UMRAM), Bilkent University, Ankara, 06800, Turkey
- Neuroscience Graduate Program, Bilkent University, Ankara, 06800, Turkey
| | - Urartu Özgür Şafak Şeker
- UNAM- Institute of Materials Science and Nanotechnology, National Nanotechnology Research Center, Bilkent University, Ankara, 06800, Turkey
- Neuroscience Graduate Program, Bilkent University, Ankara, 06800, Turkey
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12
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Arai K, Murata S, Wang T, Yoshimura W, Oda-Tokuhisa M, Matsunaga T, Kisailus D, Arakaki A. Adsorption of Biomineralization Protein Mms6 on Magnetite (Fe 3O 4) Nanoparticles. Int J Mol Sci 2022; 23:ijms23105554. [PMID: 35628364 PMCID: PMC9143127 DOI: 10.3390/ijms23105554] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Revised: 05/13/2022] [Accepted: 05/14/2022] [Indexed: 01/15/2023] Open
Abstract
Biomineralization is an elaborate process that controls the deposition of inorganic materials in living organisms with the aid of associated proteins. Magnetotactic bacteria mineralize magnetite (Fe3O4) nanoparticles with finely tuned morphologies in their cells. Mms6, a magnetosome membrane specific (Mms) protein isolated from the surfaces of bacterial magnetite nanoparticles, plays an important role in regulating the magnetite crystal morphology. Although the binding ability of Mms6 to magnetite nanoparticles has been speculated, the interactions between Mms6 and magnetite crystals have not been elucidated thus far. Here, we show a direct adsorption ability of Mms6 on magnetite nanoparticles in vitro. An adsorption isotherm indicates that Mms6 has a high adsorption affinity (Kd = 9.52 µM) to magnetite nanoparticles. In addition, Mms6 also demonstrated adsorption on other inorganic nanoparticles such as titanium oxide, zinc oxide, and hydroxyapatite. Therefore, Mms6 can potentially be utilized for the bioconjugation of functional proteins to inorganic material surfaces to modulate inorganic nanoparticles for biomedical and medicinal applications.
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Affiliation(s)
- Kosuke Arai
- Division of Biotechnology and Life Science, Institute of Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Naka-cho, Tokyo 184-8588, Japan; (K.A.); (S.M.); (W.Y.); (M.O.-T.); (T.M.)
| | - Satoshi Murata
- Division of Biotechnology and Life Science, Institute of Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Naka-cho, Tokyo 184-8588, Japan; (K.A.); (S.M.); (W.Y.); (M.O.-T.); (T.M.)
| | - Taifeng Wang
- Department of Materials Science and Engineering, University of California at Irvine, Irvine, CA 92697, USA; (T.W.); (D.K.)
| | - Wataru Yoshimura
- Division of Biotechnology and Life Science, Institute of Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Naka-cho, Tokyo 184-8588, Japan; (K.A.); (S.M.); (W.Y.); (M.O.-T.); (T.M.)
| | - Mayumi Oda-Tokuhisa
- Division of Biotechnology and Life Science, Institute of Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Naka-cho, Tokyo 184-8588, Japan; (K.A.); (S.M.); (W.Y.); (M.O.-T.); (T.M.)
| | - Tadashi Matsunaga
- Division of Biotechnology and Life Science, Institute of Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Naka-cho, Tokyo 184-8588, Japan; (K.A.); (S.M.); (W.Y.); (M.O.-T.); (T.M.)
- Japan Agency for Marine-Earth Science and Technology (JAMSTEC), 2-15 Natsushima-cho, Yokosuka 237-0061, Japan
| | - David Kisailus
- Department of Materials Science and Engineering, University of California at Irvine, Irvine, CA 92697, USA; (T.W.); (D.K.)
| | - Atsushi Arakaki
- Division of Biotechnology and Life Science, Institute of Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Naka-cho, Tokyo 184-8588, Japan; (K.A.); (S.M.); (W.Y.); (M.O.-T.); (T.M.)
- Correspondence:
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13
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Besenhard MO, Panariello L, Kiefer C, LaGrow AP, Storozhuk L, Perton F, Begin S, Mertz D, Thanh NTK, Gavriilidis A. Small iron oxide nanoparticles as MRI T1 contrast agent: scalable inexpensive water-based synthesis using a flow reactor. NANOSCALE 2021; 13:8795-8805. [PMID: 34014243 DOI: 10.1039/d1nr00877c] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Small iron oxide nanoparticles (IONPs) were synthesised in water via co-precipitation by quenching particle growth after the desired magnetic iron oxide phase formed. This was achieved in a millifluidic multistage flow reactor by precisely timed addition of an acidic solution. IONPs (≤5 nm), a suitable size for positive T1 magnetic resonance imaging (MRI) contrast agents, were obtained and stabilised continuously. This novel flow chemistry approach facilitates a reproducible and scalable production, which is a crucial paradigm shift to utilise IONPs as contrast agents and replace currently used Gd complexes. Acid addition had to be timed carefully, as the inverse spinel structure formed within seconds after initiating the co-precipitation. Late quenching allowed IONPs to grow larger than 5 nm, whereas premature acid addition yielded undesired oxide phases. Use of a flow reactor was not only essential for scalability, but also to synthesise monodisperse and non-agglomerated small IONPs as (i) co-precipitation and acid addition occurred at homogenous environment due to accurate temperature control and rapid mixing and (ii) quenching of particle growth was possible at the optimum time, i.e., a few seconds after initiating co-precipitation. In addition to the timing of growth quenching, the effect of temperature and dextran present during co-precipitation on the final particle size was investigated. This approach differs from small IONP syntheses in batch utilising either growth inhibitors (which likely leads to impurities) or high temperature methods in organic solvents. Furthermore, this continuous synthesis enables the low-cost (<£10 per g) and large-scale production of highly stable small IONPs without the use of toxic reagents. The flow-synthesised small IONPs showed high T1 contrast enhancement, with transversal relaxivity (r2) reduced to 20.5 mM-1 s-1 and longitudinal relaxivity (r1) higher than 10 mM-1 s-1, which is among the highest values reported for water-based IONP synthesis.
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Affiliation(s)
| | - Luca Panariello
- Department of Chemical Engineering, University College London, London, WC1E 7JE, UK.
| | - Céline Kiefer
- Institut de Physique et Chimie des Matériaux de Strasbourg, BP 43, 67034, Strasbourg, France
| | - Alec P LaGrow
- International Iberian Nanotechnology Laboratory, Braga 4715-330, Portugal
| | - Liudmyla Storozhuk
- Biophysics group, Department of Physics and Astronomy, University College London, London, WC1E 6BT, UK.
| | - Francis Perton
- Institut de Physique et Chimie des Matériaux de Strasbourg, BP 43, 67034, Strasbourg, France
| | - Sylvie Begin
- Institut de Physique et Chimie des Matériaux de Strasbourg, BP 43, 67034, Strasbourg, France
| | - Damien Mertz
- Institut de Physique et Chimie des Matériaux de Strasbourg, BP 43, 67034, Strasbourg, France
| | - Nguyen Thi Kim Thanh
- Biophysics group, Department of Physics and Astronomy, University College London, London, WC1E 6BT, UK. and UCL Healthcare Biomagnetic and Nanomaterials Laboratories, 21 Albemarle Street, London, W1S 4BS, UK
| | - Asterios Gavriilidis
- Department of Chemical Engineering, University College London, London, WC1E 7JE, UK.
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14
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Davidov G, Abelya G, Zalk R, Izbicki B, Shaibi S, Spektor L, Shagidov D, Meyron-Holtz EG, Zarivach R, Frank GA. Folding of an Intrinsically Disordered Iron-Binding Peptide in Response to Sedimentation Revealed by Cryo-EM. J Am Chem Soc 2020; 142:19551-19557. [PMID: 33166133 PMCID: PMC7677926 DOI: 10.1021/jacs.0c07565] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Indexed: 12/13/2022]
Abstract
Biomineralization is mediated by specialized proteins that guide and control mineral sedimentation. In many cases, the active regions of these biomineralization proteins are intrinsically disordered. High-resolution structures of these proteins while they interact with minerals are essential for understanding biomineralization processes and the function of intrinsically disordered proteins (IDPs). Here we used the cavity of ferritin as a nanoreactor where the interaction between M6A, an intrinsically disordered iron-binding domain, and an iron oxide particle was visualized at high resolution by cryo-EM. Taking advantage of the differences in the electron-dose sensitivity of the protein and the iron oxide particles, we developed a method to determine the irregular shape of the particles found in our density maps. We found that the folding of M6A correlates with the detection of mineral particles in its vicinity. M6A interacts with the iron oxide particles through its C-terminal side, resulting in the stabilization of a helix at its N-terminal side. The stabilization of the helix at a region that is not in direct contact with the iron oxide particle demonstrates the ability of IDPs to respond to signals from their surroundings by conformational changes. These findings provide the first glimpse toward the long-suspected mechanism for biomineralization protein control over mineral microstructure, where unstructured regions of these proteins become more ordered in response to their interaction with the nascent mineral particles.
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Affiliation(s)
- Geula Davidov
- Department
of Life Sciences, Ben-Gurion University
of the Negev, Beer Sheva 8410501, Israel
- The
National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, Beer Sheva 8410501, Israel
| | - Gili Abelya
- Department
of Life Sciences, Ben-Gurion University
of the Negev, Beer Sheva 8410501, Israel
| | - Ran Zalk
- The
National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, Beer Sheva 8410501, Israel
| | - Benjamin Izbicki
- Department
of Life Sciences, Ben-Gurion University
of the Negev, Beer Sheva 8410501, Israel
| | - Sharon Shaibi
- Department
of Life Sciences, Ben-Gurion University
of the Negev, Beer Sheva 8410501, Israel
| | - Lior Spektor
- Faculty
of Biotechnology and Food Engineering, Technion−Israel
Institute of Technology, Technion City, Haifa 3200000, Israel
| | - Dayana Shagidov
- Faculty
of Biotechnology and Food Engineering, Technion−Israel
Institute of Technology, Technion City, Haifa 3200000, Israel
| | - Esther G. Meyron-Holtz
- Faculty
of Biotechnology and Food Engineering, Technion−Israel
Institute of Technology, Technion City, Haifa 3200000, Israel
| | - Raz Zarivach
- Department
of Life Sciences, Ben-Gurion University
of the Negev, Beer Sheva 8410501, Israel
- The
National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, Beer Sheva 8410501, Israel
- Ilse
Katz Institute for Nanoscale Science and Technology, Ben-Gurion University of the Negev, Beer Sheva, 8410501, Israel
| | - Gabriel A. Frank
- Department
of Life Sciences, Ben-Gurion University
of the Negev, Beer Sheva 8410501, Israel
- The
National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, Beer Sheva 8410501, Israel
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15
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Investigating the ferric ion binding site of magnetite biomineralisation protein Mms6. PLoS One 2020; 15:e0228708. [PMID: 32097412 PMCID: PMC7041794 DOI: 10.1371/journal.pone.0228708] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2019] [Accepted: 01/21/2020] [Indexed: 11/19/2022] Open
Abstract
The biomineralization protein Mms6 has been shown to be a major player in the formation of magnetic nanoparticles both within the magnetosomes of magnetotactic bacteria and as an additive in synthetic magnetite precipitation assays. Previous studies have highlighted the ferric iron binding capability of the protein and this activity is thought to be crucial to its mineralizing properties. To understand how this protein binds ferric ions we have prepared a series of single amino acid substitutions within the C-terminal binding region of Mms6 and have used a ferric binding assay to probe the binding site at the level of individual residues which has pinpointed the key residues of E44, E50 and R55 involved in Mms6 ferric binding. No aspartic residues bound ferric ions. A nanoplasmonic sensing experiment was used to investigate the unstable EER44, 50,55AAA triple mutant in comparison to native Mms6. This suggests a difference in interaction with iron ions between the two and potential changes to the surface precipitation of iron oxide when the pH is increased. All-atom simulations suggest that disruptive mutations do not fundamentally alter the conformational preferences of the ferric binding region. Instead, disruption of these residues appears to impede a sequence-specific motif in the C-terminus critical to ferric ion binding.
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16
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Norfolk L, Rawlings AE, Bramble JP, Ward K, Francis N, Waller R, Bailey A, Staniland SS. Macrofluidic Coaxial Flow Platforms to Produce Tunable Magnetite Nanoparticles: A Study of the Effect of Reaction Conditions and Biomineralisation Protein Mms6. NANOMATERIALS 2019; 9:nano9121729. [PMID: 31817082 PMCID: PMC6955933 DOI: 10.3390/nano9121729] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Revised: 11/14/2019] [Accepted: 11/20/2019] [Indexed: 01/18/2023]
Abstract
Magnetite nanoparticles' applicability is growing extensively. However, simple, environmentally-friendly, tunable synthesis of monodispersed iron-oxide nanoparticles is challenging. Continuous flow microfluidic synthesis is promising; however, the microscale results in small yields and clogging. Here we present two simple macrofluidics devices (cast and machined) for precision magnetite nanoparticle synthesis utilizing formation at the interface by diffusion between two laminar flows, removing aforementioned issues. Ferric to total iron was varied between 0.2 (20:80 Fe3+:Fe2+) and 0.7 (70:30 Fe3+:Fe2+). X-ray diffraction shows magnetite in fractions from 0.2-0.6, with iron-oxide impurities in 0.7, 0.2 and 0.3 samples and magnetic susceptibility increases with increasing ferric content to 0.6, in agreement with each other and batch synthesis. Remarkably, size is tuned (between 20.5 nm to 6.5 nm) simply by increasing ferric ions ratio. Previous research shows biomineralisation protein Mms6 directs magnetite synthesis and controls size, but until now has not been attempted in flow. Here we report Mms6 increases magnetism, but no difference in particle size is seen, showing flow reduced the influence of Mms6. The study demonstrates a versatile yet simple platform for the synthesis of a vast range of tunable nanoparticles and ideal to study reaction intermediates and additive effects throughout synthesis.
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Affiliation(s)
- Laura Norfolk
- Department of Chemistry, University of Sheffield, Brook Hill, Sheffield S3 7HF, UK; (L.N.); (A.E.R.); (J.P.B.); (K.W.); (N.F.); (R.W.)
| | - Andrea E Rawlings
- Department of Chemistry, University of Sheffield, Brook Hill, Sheffield S3 7HF, UK; (L.N.); (A.E.R.); (J.P.B.); (K.W.); (N.F.); (R.W.)
- School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, UK;
| | - Jonathan P Bramble
- Department of Chemistry, University of Sheffield, Brook Hill, Sheffield S3 7HF, UK; (L.N.); (A.E.R.); (J.P.B.); (K.W.); (N.F.); (R.W.)
- School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, UK;
| | - Katy Ward
- Department of Chemistry, University of Sheffield, Brook Hill, Sheffield S3 7HF, UK; (L.N.); (A.E.R.); (J.P.B.); (K.W.); (N.F.); (R.W.)
| | - Noel Francis
- Department of Chemistry, University of Sheffield, Brook Hill, Sheffield S3 7HF, UK; (L.N.); (A.E.R.); (J.P.B.); (K.W.); (N.F.); (R.W.)
| | - Rachel Waller
- Department of Chemistry, University of Sheffield, Brook Hill, Sheffield S3 7HF, UK; (L.N.); (A.E.R.); (J.P.B.); (K.W.); (N.F.); (R.W.)
| | - Ashley Bailey
- School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, UK;
| | - Sarah S. Staniland
- Department of Chemistry, University of Sheffield, Brook Hill, Sheffield S3 7HF, UK; (L.N.); (A.E.R.); (J.P.B.); (K.W.); (N.F.); (R.W.)
- School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, UK;
- Correspondence: ; Tel.: +44-(0)114-222-9539
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17
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Rawlings AE, Somner LA, Fitzpatrick-Milton M, Roebuck TP, Gwyn C, Liravi P, Seville V, Neal TJ, Mykhaylyk OO, Baldwin SA, Staniland SS. Artificial coiled coil biomineralisation protein for the synthesis of magnetic nanoparticles. Nat Commun 2019; 10:2873. [PMID: 31253765 PMCID: PMC6599041 DOI: 10.1038/s41467-019-10578-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Accepted: 05/21/2019] [Indexed: 01/08/2023] Open
Abstract
Green synthesis of precise inorganic nanomaterials is a major challenge. Magnetotactic bacteria biomineralise magnetite nanoparticles (MNPs) within membrane vesicles (magnetosomes), which are embedded with dedicated proteins that control nanocrystal formation. Some such proteins are used in vitro to control MNP formation in green synthesis; however, these membrane proteins self-aggregate, making their production and use in vitro challenging and difficult to scale. Here, we provide an alternative solution by displaying active loops from biomineralisation proteins Mms13 and MmsF on stem-loop coiled-coil scaffold proteins (Mms13cc/MmsFcc). These artificial biomineralisation proteins form soluble, stable alpha-helical hairpin monomers, and MmsFcc successfully controls the formation of MNP when added to magnetite synthesis, regulating synthesis comparably to native MmsF. This study demonstrates how displaying active loops from membrane proteins on coiled-coil scaffolds removes membrane protein solubility issues, while retains activity, enabling a generic approach to readily-expressible, versatile, artificial membrane proteins for more accessible study and exploitation. Proteins have been used in the synthesis of magnetic nanoparticles but issues with aggregation limit this application. Here, the authors report on the synthesis of coiled proteins that display the active loop of the natural proteins to avoid aggregation and investigate the application in nanoparticle synthesis.
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Affiliation(s)
- Andrea E Rawlings
- Department of Chemistry, University of Sheffield, Sheffield, S3 7HF, UK.,School of Physics and Astronomy, University of Leeds, Leeds, LS2 9JT, UK
| | - Lori A Somner
- Department of Chemistry, University of Sheffield, Sheffield, S3 7HF, UK
| | | | - Thomas P Roebuck
- Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, UK
| | - Christopher Gwyn
- School of Physics and Astronomy, University of Leeds, Leeds, LS2 9JT, UK
| | - Panah Liravi
- Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, UK
| | - Victoria Seville
- Department of Chemistry, University of Sheffield, Sheffield, S3 7HF, UK
| | - Thomas J Neal
- Department of Chemistry, University of Sheffield, Sheffield, S3 7HF, UK
| | | | - Stephen A Baldwin
- Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, UK
| | - Sarah S Staniland
- Department of Chemistry, University of Sheffield, Sheffield, S3 7HF, UK. .,School of Physics and Astronomy, University of Leeds, Leeds, LS2 9JT, UK.
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18
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Bain J, Legge CJ, Beattie DL, Sahota A, Dirks C, Lovett JR, Staniland SS. A biomimetic magnetosome: formation of iron oxide within carboxylic acid terminated polymersomes. NANOSCALE 2019; 11:11617-11625. [PMID: 31173027 DOI: 10.1039/c9nr00498j] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Bioinspired macromolecules can aid nucleation and crystallisation of minerals by mirroring processes observed in nature. Specifically, the iron oxide magnetite (Fe3O4) is produced in a dedicated liposome (called a magnetosome) within magnetic bacteria. This process is controlled by a suite of proteins embedded within the liposome membrane. In this study we look to synthetically mimic both the liposome and nucleation proteins embedded within it using preferential orientation polymer design. Amphiphilic block co-polymers self-assemble into vesicles (polymersomes) and have been used to successfully mimic liposomes. Carboxylic acid residue-rich motifs are common place in biomineralisation nucleating proteins and several magnetosome membrane specific (Mms) proteins (namely Mms6) have a specific carboxylic acid motifs that are found to bind both ferrous and ferric iron ions and nucleate the formation of magnetite. Here we use a combination of 2 diblock co-polymers: Both have the hydrophobic 2-hydroxypropyl methacrylate (PHPMA) block with either a poly(ethylene glycol) (PEG) block or a carboxylic acid terminated poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC) block. These copolymers ((PEG113-PHPMA400) and (PMPC28-PHPMA400) respectively) self-assemble in situ to form polymersomes, with PEG113-PHPMA400 displaying favourably on the outer surface and PMPC28-PHPMA400 on the inner lumen, exposing numerous acidic iron binding carboxylates on the inner membrane. This is a polymersome mimic of a magnetosome (PMM28) containing interior nucleation sites. The resulting PMM28 were found to be 246 ± 137 nm in size. When the PMM28 were subjected to electroporation (5 pulses at 750 V) in an iron solution, iron ions were transported into the PMM28 polymersome core where magnetic iron-oxide was crystallised to fill the core; mimicking a magnetosome. Furthermore it has been shown that PMM28 magnetopolymersomes (PMM28Fe) exhibit a 6 °C temperature increase during in vitro magnetic hyperthermia yielding an intrinsic loss power (ILP) of 3.7 nHm2 kg-1. Such values are comparable to commercially available nanoparticles, but, offer the added potential for further tuning and functionalisation with respect to drug delivery.
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Affiliation(s)
- Jennifer Bain
- Department of Chemistry, University of Sheffield, Sheffield, S3 7HF, UK.
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19
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Tuning properties of biomimetic magnetic nanoparticles by combining magnetosome associated proteins. Sci Rep 2019; 9:8804. [PMID: 31217514 PMCID: PMC6584501 DOI: 10.1038/s41598-019-45219-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Accepted: 06/04/2019] [Indexed: 11/08/2022] Open
Abstract
The role of magnetosome associated proteins on the in vitro synthesis of magnetite nanoparticles has gained interest, both to obtain a better understanding of the magnetosome biomineralization process and to be able to produce novel magnetosome-like biomimetic nanoparticles. Up to now, only one recombinant protein has been used at the time to in vitro form biomimetic magnetite precipitates, being that a scenario far enough from what probably occurs in the magnetosome. In the present study, both Mms6 and MamC from Magnetococcus marinus MC-1 have been used to in vitro form biomimetic magnetites. Our results show that MamC and Mms6 have different, but complementary, effects on in vitro magnetite nucleation and growth. MamC seems to control the kinetics of magnetite nucleation while Mms6 seems to preferably control the kinetics for crystal growth. Our results from the present study also indicate that it is possible to combine both proteins to tune the properties of the resulting biomimetic magnetites. In particular, by changing the relative ratio of these proteins, better faceted and/or larger magnetite crystals with, consequently, different magnetic moment per particle could be obtained. This study provides with tools to obtain new biomimetic nanoparticles with a potential utility for biotechnological applications.
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20
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Work Patterns of MamXY Proteins during Magnetosome Formation in Magnetospirillum gryphiswaldense MSR-1. Appl Environ Microbiol 2019; 85:AEM.02394-18. [PMID: 30367002 DOI: 10.1128/aem.02394-18] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2018] [Accepted: 10/23/2018] [Indexed: 02/07/2023] Open
Abstract
The bacterium Magnetospirillum gryphiswaldense MSR-1 forms nanosized membrane-enclosed organelles termed magnetosomes. The mamXY operon, part of the magnetosome island (MAI), includes the mamY, mamX, mamZ, and ftsZ-like genes, which initiate gene transcription via the same promoter. We used a combination of molecular biological techniques (targeting of cross-linking reagents) and high-resolution mass spectrometry to investigate the coordinated activity of the four MamXY proteins in magnetite biomineralization. The FtsZ-like protein was shown by confocal laser scanning microscopy to be dispersed in the cytoplasm in the early stage of cell growth and then gradually polymerized along the magnetosome chain. Interactions of various pairs of MamXY proteins were observed using a bacterial two-hybrid system. We constructed a recombinant FtsZ-like-overexpressing strain, examined its growth patterns, and extracted magnetosome membrane proteins using a modified SDS/boiling method with BS2G-d0/d4 reagent, which helped stabilize interactions among MamXY proteins. In liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis, MamY expression was detected first and remained highest among the four proteins throughout all stages of cell growth. MamX and MamZ expression was detected subsequently. The four proteins displayed coordinated expression patterns during the magnetosome maturation process. Unique peptides discovered in the MamXY protein sequences appeared to constitute "hidden" interaction sites involved in the formation of MamXY complex that helped control magnetosome shape and size.IMPORTANCE mamXY operon genes play an essential role in magnetite biomineralization, participate in redox reactions, and control magnetosome shape and size. However, mechanisms whereby the four MamXY proteins function together in iron oxidoreduction and transport are poorly understood. We used a combination of targeted cross-linking techniques and high-resolution mass spectrometry to elucidate the coordinated activity patterns of the MamXY proteins during magnetite biomineralization. Our findings indicate that the FtsZ-like protein undergoes polymerization and then recruits MamY, MamX, and MamZ in turn, and that these interactions depend on unique peptides present in the protein sequences. A hypothetical model of the functionalities of these proteins is proposed that accounts for the findings and provides a basis for further studies of coordination among magnetosome island (MAI) gene clusters during the process of magnetosome formation.
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21
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Nudelman H, Lee YZ, Hung YL, Kolusheva S, Upcher A, Chen YC, Chen JY, Sue SC, Zarivach R. Understanding the Biomineralization Role of Magnetite-Interacting Components (MICs) From Magnetotactic Bacteria. Front Microbiol 2018; 9:2480. [PMID: 30405554 PMCID: PMC6206293 DOI: 10.3389/fmicb.2018.02480] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Accepted: 09/28/2018] [Indexed: 11/20/2022] Open
Abstract
Biomineralization is a process that takes place in all domains of life and which usually helps organisms to harden soft tissues by creating inorganic structures that facilitate their biological functions. It was shown that biominerals are under tight biological control via proteins that are involved in nucleation initiation and/or which act as structural skeletons. Magnetotactic bacteria (MTB) use iron biomineralization to create nano-magnetic particles in a specialized organelle, the magnetosome, to align to the geomagnetic field. A specific set of magnetite-associated proteins (MAPs) is involved in regulating magnetite nucleation, size, and shape. These MAPs are all predicted to contain specific 17–22 residue-long sequences involved in magnetite formation. To understand the mechanism of magnetite formation, we focused on three different MAPs, MamC, Mms6 and Mms7, and studied the predicted iron-binding sequences. Using nuclear magnetic resonance (NMR), we differentiated the recognition mode of each MAP based on ion specificity, affinity, and binding residues. The significance of critical residues in each peptide was evaluated by mutation followed by an iron co-precipitation assay. Among the peptides, MamC showed weak ion binding but created the most significant effect in enhancing magnetite particle size, indicating the potency in controlling magnetite particle shape and size. Alternatively, Mms6 and Mms7 had strong binding affinities but less effect in modulating magnetite particle size, representing their major role potentially in initiating nucleation by increasing local metal concentration. Overall, our results explain how different MAPs affect magnetite synthesis, interact with Fe2+ ions and which residues are important for the MAPs functions.
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Affiliation(s)
- Hila Nudelman
- Department of Life Sciences and the National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Yi-Zong Lee
- Institute of Bioinformatics and Structural Biology, National Tsing Hua University, Hsinchu, Taiwan.,Instrumentation Center, National Tsing Hua University, Hsinchu, Taiwan
| | - Yi-Lin Hung
- Institute of Bioinformatics and Structural Biology, National Tsing Hua University, Hsinchu, Taiwan.,Instrumentation Center, National Tsing Hua University, Hsinchu, Taiwan
| | - Sofiya Kolusheva
- Ilse Katz Institute for Nanoscale Science & Technology, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Alexander Upcher
- Ilse Katz Institute for Nanoscale Science & Technology, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Yi-Chen Chen
- Institute of Bioinformatics and Structural Biology, National Tsing Hua University, Hsinchu, Taiwan
| | - Jih-Ying Chen
- Institute of Bioinformatics and Structural Biology, National Tsing Hua University, Hsinchu, Taiwan
| | - Shih-Che Sue
- Institute of Bioinformatics and Structural Biology, National Tsing Hua University, Hsinchu, Taiwan
| | - Raz Zarivach
- Department of Life Sciences and the National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, Beer Sheva, Israel.,Ilse Katz Institute for Nanoscale Science & Technology, Ben-Gurion University of the Negev, Beer Sheva, Israel
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22
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Kotelnikova PA, Shipunova VO, Aghayeva UF, Stremovskiy OA, Nikitin MP, Novikov IA, Schulga AA, Deyev SM, Petrov RV. Synthesis of Magnetic Nanoparticles Stabilized by Magnetite-Binding Protein for Targeted Delivery to Cancer Cells. DOKL BIOCHEM BIOPHYS 2018; 481:198-200. [PMID: 30168058 DOI: 10.1134/s1607672918040051] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Indexed: 01/29/2023]
Abstract
A new method for obtaining biomodified magnetite nanoparticles for targeted delivery to cells was developed. The method is based on the use of the C-terminal fragment of the Mms6 protein, which is involved in the magnetite biomineralization during the synthesis of magnetosomes in magnetotactic bacteria Magnetospirillum magneticum AMB-1, and the barnase*barstar high-affinity protein pair. The Mms6 protein fragment is required for stabilizing magnetite, and the barnase*barstar pair mediates the interaction between nanoparticles and the component for modification. The efficiency of this method was confirmed in the synthesis of magnetite nanoparticles recognizing the HER2/neu tumor marker and in the selective labeling of HER2/neu with these nanoparticles on the surface of cancer cells.
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Affiliation(s)
- P A Kotelnikova
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia.,Moscow Institute of Physics and Technology (State University), Dolgoprudnyi, Moscow oblast, Russia
| | - V O Shipunova
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia. .,Moscow Institute of Physics and Technology (State University), Dolgoprudnyi, Moscow oblast, Russia. .,National Research Nuclear University "MEPhI,", Moscow, Russia.
| | - U F Aghayeva
- Department of Biological Sciences, Howard Hughes Medical Institute, Columbia University, New York, 10027, USA
| | - O A Stremovskiy
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - M P Nikitin
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia.,Moscow Institute of Physics and Technology (State University), Dolgoprudnyi, Moscow oblast, Russia
| | - I A Novikov
- Research Institute of Eye Diseases, Moscow, Russia
| | - A A Schulga
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - S M Deyev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia.,National Research Nuclear University "MEPhI,", Moscow, Russia
| | - R V Petrov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
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23
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Ramesh P, Hwang S, Davis HC, Lee‐Gosselin A, Bharadwaj V, English MA, Sheng J, Iyer V, Shapiro MG. Ultraparamagnetic Cells Formed through Intracellular Oxidation and Chelation of Paramagnetic Iron. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201805042] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Pradeep Ramesh
- Division of Biology and Biological Engineering California Institute of Technology Pasadena CA 91125 USA
| | - Son‐Jong Hwang
- Division of Chemistry and Chemical Engineering California Institute of Technology Pasadena CA 91125 USA
| | - Hunter C. Davis
- Division of Chemistry and Chemical Engineering California Institute of Technology Pasadena CA 91125 USA
| | - Audrey Lee‐Gosselin
- Division of Chemistry and Chemical Engineering California Institute of Technology Pasadena CA 91125 USA
| | - Vivek Bharadwaj
- Division of Engineering and Applied Science California Institute of Technology Pasadena CA 91125 USA
| | - Max A. English
- Division of Engineering and Applied Science California Institute of Technology Pasadena CA 91125 USA
| | - Jenny Sheng
- Division of Engineering and Applied Science California Institute of Technology Pasadena CA 91125 USA
| | - Vasant Iyer
- Division of Engineering and Applied Science California Institute of Technology Pasadena CA 91125 USA
| | - Mikhail G. Shapiro
- Division of Chemistry and Chemical Engineering California Institute of Technology Pasadena CA 91125 USA
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24
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Ramesh P, Hwang SJ, Davis HC, Lee-Gosselin A, Bharadwaj V, English MA, Sheng J, Iyer V, Shapiro MG. Ultraparamagnetic Cells Formed through Intracellular Oxidation and Chelation of Paramagnetic Iron. Angew Chem Int Ed Engl 2018; 57:12385-12389. [PMID: 30089191 DOI: 10.1002/anie.201805042] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Revised: 07/03/2018] [Indexed: 12/19/2022]
Abstract
Making cells magnetic is a long-standing goal of chemical biology, aiming to enable the separation of cells from complex biological samples and their visualization in vivo using magnetic resonance imaging (MRI). Previous efforts towards this goal, focused on engineering cells to biomineralize superparamagnetic or ferromagnetic iron oxides, have been largely unsuccessful due to the stringent required chemical conditions. Here, we introduce an alternative approach to making cells magnetic, focused on biochemically maximizing cellular paramagnetism. We show that a novel genetic construct combining the functions of ferroxidation and iron chelation enables engineered bacterial cells to accumulate iron in "ultraparamagnetic" macromolecular complexes, allowing these cells to be trapped with magnetic fields and imaged with MRI in vitro and in vivo. We characterize the properties of these cells and complexes using magnetometry, nuclear magnetic resonance, biochemical assays, and computational modeling to elucidate the unique mechanisms and capabilities of this paramagnetic concept.
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Affiliation(s)
- Pradeep Ramesh
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, 91125, USA
| | - Son-Jong Hwang
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA, 91125, USA
| | - Hunter C Davis
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA, 91125, USA
| | - Audrey Lee-Gosselin
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA, 91125, USA
| | - Vivek Bharadwaj
- Division of Engineering and Applied Science, California Institute of Technology, Pasadena, CA, 91125, USA
| | - Max A English
- Division of Engineering and Applied Science, California Institute of Technology, Pasadena, CA, 91125, USA
| | - Jenny Sheng
- Division of Engineering and Applied Science, California Institute of Technology, Pasadena, CA, 91125, USA
| | - Vasant Iyer
- Division of Engineering and Applied Science, California Institute of Technology, Pasadena, CA, 91125, USA
| | - Mikhail G Shapiro
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA, 91125, USA
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25
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Nudelman H, Perez Gonzalez T, Kolushiva S, Widdrat M, Reichel V, Peigneux A, Davidov G, Bitton R, Faivre D, Jimenez-Lopez C, Zarivach R. The importance of the helical structure of a MamC-derived magnetite-interacting peptide for its function in magnetite formation. ACTA CRYSTALLOGRAPHICA SECTION D-STRUCTURAL BIOLOGY 2018; 74:10-20. [PMID: 29372895 DOI: 10.1107/s2059798317017491] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Accepted: 12/05/2017] [Indexed: 01/30/2023]
Abstract
Biomineralization is the process of mineral formation by organisms and involves the uptake of ions from the environment in order to produce minerals, with the process generally being mediated by proteins. Most proteins that are involved in mineral interactions are predicted to contain disordered regions containing large numbers of negatively charged amino acids. Magnetotactic bacteria, which are used as a model system for iron biomineralization, are Gram-negative bacteria that can navigate through geomagnetic fields using a specific organelle, the magnetosome. Each organelle comprises a membrane-enveloped magnetic nanoparticle, magnetite, the formation of which is controlled by a specific set of proteins. One of the most abundant of these proteins is MamC, a small magnetosome-associated integral membrane protein that contains two transmembrane α-helices connected by an ∼21-amino-acid peptide. In vitro studies of this MamC peptide showed that it forms a helical structure that can interact with the magnetite surface and affect the size and shape of the growing crystal. Our results show that a disordered structure of the MamC magnetite-interacting component (MamC-MIC) abolishes its interaction with magnetite particles. Moreover, the size and shape of magnetite crystals grown in in vitro magnetite-precipitation experiments in the presence of this disordered peptide were different from the traits of crystals grown in the presence of other peptides or in the presence of the helical MIC. It is suggested that the helical structure of the MamC-MIC is important for its function during magnetite formation.
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Affiliation(s)
- Hila Nudelman
- Department of Life Sciences and the National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Teresa Perez Gonzalez
- Departamento de Microbiologia, Campus de Fuentenueva, Universidad de Granada, 18071 Granada, Spain
| | - Sofiya Kolushiva
- Ilse Katz Institute for Nanoscale Science and Technology, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Marc Widdrat
- Department of Biomaterials, Max Planck Institute of Colloids and Interfaces, Potsdam, Germany
| | - Victoria Reichel
- Department of Biomaterials, Max Planck Institute of Colloids and Interfaces, Potsdam, Germany
| | - Ana Peigneux
- Departamento de Microbiologia, Campus de Fuentenueva, Universidad de Granada, 18071 Granada, Spain
| | - Geula Davidov
- Department of Life Sciences and the National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Ronit Bitton
- Ilse Katz Institute for Nanoscale Science and Technology, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Damien Faivre
- Department of Biomaterials, Max Planck Institute of Colloids and Interfaces, Potsdam, Germany
| | - Concepcion Jimenez-Lopez
- Departamento de Microbiologia, Campus de Fuentenueva, Universidad de Granada, 18071 Granada, Spain
| | - Raz Zarivach
- Department of Life Sciences and the National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, Beer Sheva, Israel
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26
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Bereczk-Tompa É, Vonderviszt F, Horváth B, Szalai I, Pósfai M. Biotemplated synthesis of magnetic filaments. NANOSCALE 2017; 9:15062-15069. [PMID: 28967665 DOI: 10.1039/c7nr04842d] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
With the aim of creating one-dimensional magnetic nanostructures, we genetically engineered flagellar filaments produced by Salmonella bacteria to display iron- or magnetite-binding sites, and used the mutant filaments as templates for both nucleation and attachment of the magnetic iron oxide magnetite. Although nucleation from solution and attachment of nanoparticles to a pre-existing surface are two different processes, non-classical crystal nucleation pathways have been increasingly recognized in biological systems, and in many cases nucleation and particle attachment cannot be clearly distinguished. In this study we tested the magnetite-nucleating ability of four types of mutant flagella previously shown to be efficient binders of magnetite nanoparticles, and we used two other mutant flagella that were engineered to periodically display known iron-binding oligopeptides on their surfaces. All mutant filaments were demonstrated to be efficient as templates for the synthesis of one-dimensional magnetic nanostructures under ambient conditions. Both approaches resulted in similar final products, with randomly oriented magnetite nanoparticles partially covering the filamentous biological templates. In an external magnetic field, the viscosity of a suspension of the produced magnetic filaments showed a twofold increase relative to the control sample. The results of magnetic susceptibility measurements were also consistent with the magnetic nanoparticles occurring in linear structures. Our study demonstrates that biological templating can be used to produce one-dimensional magnetic nanostructures under benign conditions, and that modified flagellar filaments can be used for creating model systems in which crystal nucleation from solution can be experimentally studied.
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Affiliation(s)
- Éva Bereczk-Tompa
- Department of Earth and Environmental Sciences, University of Pannonia, Egyetem u. 10, 8200 Veszprém, Hungary.
| | - Ferenc Vonderviszt
- Bio-Nanosystems Laboratory, Research Institute of Biomolecular and Chemical Engineering, University of Pannonia, Egyetem u. 10, 8200 Veszprém, Hungary. and Institute of Technical Physics and Materials Science, Centre for Energy Research, Konkoly-Thege u. 29-33, 1121 Budapest, Hungary
| | - Barnabás Horváth
- Institute of Physics and Mechatronics, University of Pannonia, Egyetem u. 10, 8200 Veszprém, Hungary.
| | - István Szalai
- Institute of Physics and Mechatronics, University of Pannonia, Egyetem u. 10, 8200 Veszprém, Hungary.
| | - Mihály Pósfai
- Department of Earth and Environmental Sciences, University of Pannonia, Egyetem u. 10, 8200 Veszprém, Hungary.
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27
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Crystallizing the function of the magnetosome membrane mineralization protein Mms6. Biochem Soc Trans 2017; 44:883-90. [PMID: 27284056 PMCID: PMC4900750 DOI: 10.1042/bst20160057] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Indexed: 12/18/2022]
Abstract
The literature on the magnetosome membrane (MM) protein, magnetosome membrane specific6 (Mms6), is reviewed. Mms6 is native to magnetotactic bacteria (MTB). These bacteria take up iron from solution and biomineralize magnetite nanoparticles within organelles called magnetosomes. Mms6 is a small protein embedded on the interior of the MM and was discovered tightly associated with the formed mineral. It has been the subject of intensive research as it is seen to control the formation of particles both in vivo and in vitro. Here, we compile, review and discuss the research detailing Mms6’s activity within the cell and in a range of chemical in vitro methods where Mms6 has a marked effect on the composition, size and distribution of synthetic particles, with approximately 21 nm in size for solution precipitations and approximately 90 nm for those formed on surfaces. Furthermore, we review and discuss recent work detailing the structure and function of Mms6. From the evidence, we propose a mechanism for its function as a specific magnetite nucleation protein and summaries the key features for this action: namely, self-assembly to display a charged surface for specific iron binding, with the curvature of the surfaces determining the particle size. We suggest these may aid design of biomimetic additives for future green nanoparticle production.
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28
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Barber-Zucker S, Zarivach R. A Look into the Biochemistry of Magnetosome Biosynthesis in Magnetotactic Bacteria. ACS Chem Biol 2017; 12:13-22. [PMID: 27930882 DOI: 10.1021/acschembio.6b01000] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Magnetosomes are protein-rich membrane organelles that encapsulate magnetite or greigite and whose chain alignment enables magnetotactic bacteria (MTB) to sense the geomagnetic field. As these bacteria synthesize uniform magnetic particles, their biomineralization mechanism is of great interest among researchers from different fields, from material engineering to medicine. Both magnetosome formation and magnetic particle synthesis are highly controlled processes that can be divided into several crucial steps: membrane invagination from the inner-cell membrane, protein sorting, the magnetosomes' arrangement into chains, iron transport, chemical environment regulation of the magnetosome lumen, magnetic particle nucleation, and finally crystal growth, size, and morphology control. This complex system involves an ensemble of unique proteins that participate in different stages during magnetosome formation, some of which were extensively studied in recent years. Here, we present the current knowledge on magnetosome biosynthesis with a focus on the different proteins and the main biochemical pathways along this process.
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Affiliation(s)
- Shiran Barber-Zucker
- Department of Life
Sciences,
the National Institute for Biotechnology in the Negev and Ilse Katz
Institute for Nanoscale Science and Technology, Ben-Gurion University of the Negev, Beer Sheva, 8410501, Israel
| | - Raz Zarivach
- Department of Life
Sciences,
the National Institute for Biotechnology in the Negev and Ilse Katz
Institute for Nanoscale Science and Technology, Ben-Gurion University of the Negev, Beer Sheva, 8410501, Israel
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29
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Ma K, Zhao H, Zheng X, Sun H, Hu L, Zhu L, Shen Y, Luo T, Dai H, Wang J. NMR studies of the interactions between AMB-1 Mms6 protein and magnetosome Fe3O4 nanoparticles. J Mater Chem B 2017; 5:2888-2895. [DOI: 10.1039/c7tb00570a] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
NMR studies demonstrate that, the C-terminal Mms6 undergo conformation change upon magnetosome Fe3O4 crystals binding. The N-terminal hydrophobic packing arranges the DEEVE motifs into a correct assembly and orientation for magnetite crystal recognition.
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30
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Core Amino Acid Residues in the Morphology-Regulating Protein, Mms6, for Intracellular Magnetite Biomineralization. Sci Rep 2016; 6:35670. [PMID: 27759096 PMCID: PMC5069546 DOI: 10.1038/srep35670] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2016] [Accepted: 09/15/2016] [Indexed: 01/15/2023] Open
Abstract
Living organisms produce finely tuned biomineral architectures with the aid of biomineral-associated proteins. The functional amino acid residues in these proteins have been previously identified using in vitro and in silico experimentation in different biomineralization systems. However, the investigation in living organisms is limited owing to the difficulty in establishing appropriate genetic techniques. Mms6 protein, isolated from the surface of magnetite crystals synthesized in magnetotactic bacteria, was shown to play a key role in the regulation of crystal morphology. In this study, we have demonstrated a defect in the specific region or substituted acidic amino acid residues in the Mms6 protein for observing their effect on magnetite biomineralization in vivo. Analysis of the gene deletion mutants and transformants of Magnetospirillum magneticum AMB-1 expressing partially truncated Mms6 protein revealed that deletions in the N-terminal or C-terminal regions disrupted proper protein localization to the magnetite surface, resulting in a change in the crystal morphology. Moreover, single amino acid substitutions at Asp123, Glu124, or Glu125 in the C-terminal region of Mms6 clearly indicated that these amino acid residues had a direct impact on magnetite crystal morphology. Thus, these consecutive acidic amino acid residues were found to be core residues regulating magnetite crystal morphology.
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31
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Bereczk-Tompa É, Pósfai M, Tóth B, Vonderviszt F. Magnetite-Binding Flagellar Filaments Displaying the MamI Loop Motif. Chembiochem 2016; 17:2075-2082. [PMID: 27528487 DOI: 10.1002/cbic.201600377] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2016] [Indexed: 12/11/2022]
Abstract
This work aimed at developing a novel method for fabricating 1 D magnetite nanostructures with the help of mutated flagellar filaments. We constructed four different flagellin mutants displaying magnetite-binding motifs: two contained fragments of magnetosome-associated proteins from magnetotactic bacteria (MamI and Mms6), and synthetic sequences were used for the other two. A magnetic selection method identified the MamI mutant as having the highest binding affinity to magnetite. Filaments built from MamI loop-containing flagellin subunits were used as templates to form chains of magnetite nanoparticles along the filament by capturing them from suspension. Our study represents a proof-of-concept that flagellar filaments can be engineered to facilitate formation of 1 D magnetite nanostructures under ambient conditions. In addition, it proves the interaction between MamI and magnetite, with implications for the role of this protein in magnetotactic bacteria.
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Affiliation(s)
- Éva Bereczk-Tompa
- Department of Earth and Environmental Sciences, University of Pannonia, Egyetem u. 10, 8200, Veszprém, Hungary
| | - Mihály Pósfai
- Department of Earth and Environmental Sciences, University of Pannonia, Egyetem u. 10, 8200, Veszprém, Hungary
| | - Balázs Tóth
- Bio-Nanosystems Laboratory, Research Institute for Biomolecular and Chemical Engineering, University of Pannonia, Egyetem u. 10, 8200, Veszprém, Hungary
| | - Ferenc Vonderviszt
- Bio-Nanosystems Laboratory, Research Institute for Biomolecular and Chemical Engineering, University of Pannonia, Egyetem u. 10, 8200, Veszprém, Hungary. .,Institute of Technical Physics and Materials Science, Centre for Energy Research, Konkoly-Thege u. 29-33, 1121, Budapest, Hungary.
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32
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Lenders JJM, Mirabello G, Sommerdijk NAJM. Bioinspired magnetite synthesis via solid precursor phases. Chem Sci 2016; 7:5624-5634. [PMID: 30034699 PMCID: PMC6021960 DOI: 10.1039/c6sc00523c] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Accepted: 06/12/2016] [Indexed: 12/15/2022] Open
Abstract
Living organisms often exploit solid but poorly ordered mineral phases as precursors in the biomineralization of their inorganic body parts.
Living organisms often exploit solid but poorly ordered mineral phases as precursors in the biomineralization of their inorganic body parts. Generally speaking, such precursor-based approaches allow the organisms – without the need of high supersaturation levels – to accumulate significant quantities of mineral material at the desired place and time, where they can be molded and crystallized into the right morphology and structure. This strategy is also of interest in the field of bioinspired materials science, as it potentially enables the bottom-up creation of novel materials with equal or improved functionality as compared to Nature, in water and at ambient temperatures. Also for the biomineralization of magnetite (Fe3O4) such a strategy has been reported: ferrihydrite, a poorly crystalline iron oxide, has been identified as a precursor for the final magnetite phase in the magnetosomes of magnetotactic bacteria as well as in the outer layers of chiton teeth. In this perspective, we discuss the efforts of us and others to understand and tune the nucleation and growth of magnetite crystals to date, in aqueous, room-temperature syntheses and employing different solid precursor phases. The various examples demonstrate the importance of the precursor approach in controlling the different properties of magnetite nanoparticles.
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Affiliation(s)
- Jos J M Lenders
- Laboratory of Materials and Interface Chemistry , Centre for Multiscale Electron Microscopy , Department of Chemical Engineering and Chemistry , Institute for Complex Molecular Systems , Eindhoven University of Technology , PO box 513 , 5600 MB Eindhoven , The Netherlands .
| | - Giulia Mirabello
- Laboratory of Materials and Interface Chemistry , Centre for Multiscale Electron Microscopy , Department of Chemical Engineering and Chemistry , Institute for Complex Molecular Systems , Eindhoven University of Technology , PO box 513 , 5600 MB Eindhoven , The Netherlands .
| | - Nico A J M Sommerdijk
- Laboratory of Materials and Interface Chemistry , Centre for Multiscale Electron Microscopy , Department of Chemical Engineering and Chemistry , Institute for Complex Molecular Systems , Eindhoven University of Technology , PO box 513 , 5600 MB Eindhoven , The Netherlands .
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Rawlings AE, Bramble JP, Hounslow AM, Williamson MP, Monnington AE, Cooke DJ, Staniland SS. Ferrous Iron Binding Key to Mms6 Magnetite Biomineralisation: A Mechanistic Study to Understand Magnetite Formation Using pH Titration and NMR Spectroscopy. Chemistry 2016; 22:7885-94. [PMID: 27112228 PMCID: PMC5082532 DOI: 10.1002/chem.201600322] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2016] [Indexed: 12/12/2022]
Abstract
Formation of magnetite nanocrystals by magnetotactic bacteria is controlled by specific proteins which regulate the particles’ nucleation and growth. One such protein is Mms6. This small, amphiphilic protein can self‐assemble and bind ferric ions to aid in magnetite formation. To understand the role of Mms6 during in vitro iron oxide precipitation we have performed in situ pH titrations. We find Mms6 has little effect during ferric salt precipitation, but exerts greatest influence during the incorporation of ferrous ions and conversion of this salt to mixed‐valence iron minerals, suggesting Mms6 has a hitherto unrecorded ferrous iron interacting property which promotes the formation of magnetite in ferrous‐rich solutions. We show ferrous binding to the DEEVE motif within the C‐terminal region of Mms6 by NMR spectroscopy, and model these binding events using molecular simulations. We conclude that Mms6 functions as a magnetite nucleating protein under conditions where ferrous ions predominate.
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Affiliation(s)
- Andrea E Rawlings
- Department of Chemistry, University of Sheffield, Sheffield, S3 7HF, UK
| | | | - Andrea M Hounslow
- Department of Molecular Biology and Biotechnology, University of Sheffield, Firth Court, Western Bank, Sheffield, S10 2TN, UK
| | - Michael P Williamson
- Department of Molecular Biology and Biotechnology, University of Sheffield, Firth Court, Western Bank, Sheffield, S10 2TN, UK
| | - Amy E Monnington
- Department of Chemical and Biological Sciences, University of Huddersfield, Queensgate, Huddersfield, HD1 3DH, UK
| | - David J Cooke
- Department of Chemical and Biological Sciences, University of Huddersfield, Queensgate, Huddersfield, HD1 3DH, UK
| | - Sarah S Staniland
- Department of Chemistry, University of Sheffield, Sheffield, S3 7HF, UK.
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