1
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Characterization of DNA-protein complexes by nanoparticle tracking analysis and their association with systemic lupus erythematosus. Proc Natl Acad Sci U S A 2021; 118:2106647118. [PMID: 34301873 DOI: 10.1073/pnas.2106647118] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Nanotechnology enables investigations of single biomacromolecules, but technical challenges have limited the application in liquid biopsies, for example, blood plasma. Nonetheless, tools to characterize single molecular species in such samples represent a significant unmet need with the increasing appreciation of the physiological importance of protein structural changes at nanometer scale. Mannose-binding lectin (MBL) is an oligomeric plasma protein and part of the innate immune system through its ability to activate complement. MBL also serves a role as a scavenger for cellular debris, especially DNA. This may link functions of MBL with several inflammatory diseases in which cell-free DNA now appears to play a role, but mechanistic insight has been lacking. By making nanoparticle tracking analysis possible in human plasma, we now show that superoligomeric structures of MBL form nanoparticles with DNA. These oligomers correlate with disease activity in systemic lupus erythematosus patients. With the direct quantification of the hydrodynamic radius, calculations following the principles of Taylor dispersion in the blood stream connect the size of these complexes to endothelial inflammation, which is among the most important morbidities in lupus. Mechanistic insight from an animal model of lupus supported that DNA-stabilized superoligomers stimulate the formation of germinal center B cells and drive loss of immunological tolerance. The formation involves an inverse relationship between the concentration of MBL superoligomers and antibodies to double-stranded DNA. Our approach implicates the structure of DNA-protein nanoparticulates in the pathobiology of autoimmune diseases.
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2
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Zhu Y, Li C, Cui H, Lin L. Encapsulation strategies to enhance the antibacterial properties of essential oils in food system. Food Control 2021. [DOI: 10.1016/j.foodcont.2020.107856] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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3
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Chen Y, Zhang Z, Xin Y, Zhou R, Jiang K, Sun X, He D, Song J, Zhang Y. Synergistic transdermal delivery of nanoethosomes embedded in hyaluronic acid nanogels for enhancing photodynamic therapy. NANOSCALE 2020; 12:15435-15442. [PMID: 32662485 DOI: 10.1039/d0nr03494k] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Photodynamic therapy (PDT) is a new therapeutic strategy for hypertrophic scars (HS), but it is limited by low drug utilization. Transdermal delivery based on nanoethosomes (ES) has attracted considerable attention as a potential clinical strategy in PDT treating HS. However, free ES are unsatisfactory due to their instability and non-targeting, which causes non-effective delivery and low drug utilization. Herein, 5-aminolevulinic acid (ALA)-loaded ES (ES-ALA) embedded in hyaluronic acid (HA) meshes (HA/ES-ALA), a novel synergistic transdermal delivery nanogel, are developed for enhancing PDT of HS. HA/ES-ALA has a unique structure and property to protect unilaminar ES-ALA with HA meshes and actively target hypertrophic scar fibroblasts (HSFs) with HA receptors. Both in vitro and in vivo experiments demonstrate that HA/ES-ALA has a remarkable transdermal delivery ability with penetrating channels and a membrane-fusion mechanism. Meanwhile, the synergistic delivery mechanism is visually characterized as three stages: synergistic penetration, targeting aggregation and transmembrane delivery. With the synergistic effect, HA/ES-ALA can realize a targeted transdermal delivery, and significantly improve ALA utilization and enhance PDT efficacy. The results demonstrate an effective transdermal delivery route to enhance therapy for HS as well as other skin diseases.
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Affiliation(s)
- Yunsheng Chen
- Department of Plastic and Reconstructive Surgery, Shanghai Ninth People's Hospital, School of Medicine, Shanghai Jiao Tong University, 639 Zhizaoju Road, Shanghai 200011, P.R. China.
| | - Zheng Zhang
- Department of Plastic and Reconstructive Surgery, Shanghai Ninth People's Hospital, School of Medicine, Shanghai Jiao Tong University, 639 Zhizaoju Road, Shanghai 200011, P.R. China.
| | - Yu Xin
- Department of Plastic and Reconstructive Surgery, Shanghai Ninth People's Hospital, School of Medicine, Shanghai Jiao Tong University, 639 Zhizaoju Road, Shanghai 200011, P.R. China.
| | - Rong Zhou
- Department of Orthopedic, Changzheng Hospital, Second Military Medical University, Shanghai, China
| | - Kai Jiang
- Institute of Nano Biomedicine and Engineering, Shanghai Engineering Research Center for Intelligent Instrument for Diagnosis and Therapy, 800 Dongchuan Road, Shanghai Jiao Tong University, Shanghai 200240, P.R. China.
| | - Xiyang Sun
- Hongqiao International Institute of Medicine, Tongren Hospital, School of Medicine, Shanghai Jiao Tong University, 1111 XianXia Road, Shanghai, 200336, China.
| | - Dannong He
- Shanghai National Engineering Research Center for Nanotechnology, 245 Jiachuan Road, Shanghai 200237, PR China
| | - Jie Song
- Institute of Nano Biomedicine and Engineering, Shanghai Engineering Research Center for Intelligent Instrument for Diagnosis and Therapy, 800 Dongchuan Road, Shanghai Jiao Tong University, Shanghai 200240, P.R. China.
| | - Yixin Zhang
- Department of Plastic and Reconstructive Surgery, Shanghai Ninth People's Hospital, School of Medicine, Shanghai Jiao Tong University, 639 Zhizaoju Road, Shanghai 200011, P.R. China. and Shanghai National Engineering Research Center for Nanotechnology, 245 Jiachuan Road, Shanghai 200237, PR China
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4
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Møller Sønderskov S, Hyldgaard Klausen L, Amland Skaanvik S, Han X, Dong M. In situ Surface Charge Density Visualization of Self-assembled DNA Nanostructures after Ion Exchange. Chemphyschem 2020; 21:1474-1482. [PMID: 32330354 PMCID: PMC7891384 DOI: 10.1002/cphc.201901168] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Revised: 04/14/2020] [Indexed: 12/30/2022]
Abstract
The charge density of DNA is a key parameter in strand hybridization and for the interactions occurring between DNA and molecules in biological systems. Due to the intricate structure of DNA, visualization of the surface charge density of DNA nanostructures under physiological conditions was not previously possible. Here, we perform a simultaneous analysis of the topography and surface charge density of DNA nanostructures using atomic force microscopy and scanning ion conductance microscopy. The effect of in situ ion exchange using various alkali metal ions is tested with respect to the adsorption of DNA origami onto mica, and a quantitative study of surface charge density reveals ion exchange phenomena in mica as a key parameter in DNA adsorption. This is important for structure-function studies of DNA nanostructures. The research provides an efficient approach to study surface charge density of DNA origami nanostructures and other biological molecules at a single molecule level.
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Affiliation(s)
| | - Lasse Hyldgaard Klausen
- Interdisciplinary Nanoscience Center (iNANO)Aarhus University, Denmark
- Department of ChemistryStanford University333 Campus DriveStanfordCA 94305USA
| | | | - Xiaojun Han
- State Key Laboratory of Urban Water Resource and EnvironmentSchool of Chemistry and Chemical EngineeringHarbin Institute of Technology, China
| | - Mingdong Dong
- Interdisciplinary Nanoscience Center (iNANO)Aarhus University, Denmark
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5
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Siva S, Li C, Cui H, Meenatchi V, Lin L. Encapsulation of essential oil components with methyl-β-cyclodextrin using ultrasonication: Solubility, characterization, DPPH and antibacterial assay. ULTRASONICS SONOCHEMISTRY 2020; 64:104997. [PMID: 32058914 DOI: 10.1016/j.ultsonch.2020.104997] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2019] [Revised: 01/24/2020] [Accepted: 02/03/2020] [Indexed: 06/10/2023]
Abstract
Essential oils derived from medicinal plants are prosperous sources of active components having high biological potential. Cuminaldehye and isoeugenol, are hydrophobic essential oil components (EOC), are showing drastic limitations in their applications by low water solubility and the respective volatility. Methyl-β-cyclodextrin inclusion complexes (MβCD-ICs) were prepared in aqueous solution and in solid state with the EOC via the ultrasonication method, an energy saving, high efficiency and eco-friend technique, aim to extend their aqueous solubility and biological properties. UV-Vis absorption, fluorescence, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), proton nuclear magnetic resonance (1H NMR) spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, powder X-ray diffraction (PXRD) and computational simulations confirmed the formation of EOC/MβCD-ICs. Result of solubility studies proved the enhanced solubilization of EOC in the presence of MβCD in aqueous and double reciprocal profiles substantiated the guest/host stoichiometry of 1:1. TGA and DSC studies indicated the improved stability of EOC in MβCD-ICs. The efficiency of ICs in terms of the antioxidant activity was verified and the IC displayed higher antioxidant activity compared to that of free EOC, as determined by free radical scavenging assay. Finally, the antibacterial effect of EOC/MβCD-ICs against gram-positive Staphylococcus aureus and gram-negative Escherichia coli bacteria was demonstrated. Overall results not only revealed the potential of MβCD on the bioavailability, solubility and stability, but also that the intensification caused by the IC may be greater that the antioxidant and antibacterial effects of the selected EOC for this study.
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Affiliation(s)
- Subramanian Siva
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang 212013, China
| | - Changzhu Li
- Department of Bioresource, Hunan Academy of Forestry, Changsha 410007, China
| | - Haiying Cui
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang 212013, China.
| | - Venkatasamy Meenatchi
- School of Environment and Safety Engineering, Jiangsu University, Zhenjiang 212013, China
| | - Lin Lin
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang 212013, China.
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6
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Zhu J, Tian Y, Tian L, Wang Z, Liu X. Mechanobiology Analysis of Manifold Live Cells in Vitro with Atomic Force Acoustic Microscopy. ACS APPLIED BIO MATERIALS 2020; 3:1210-1215. [DOI: 10.1021/acsabm.9b01105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jiajing Zhu
- School of Engineering, University of Warwick, Coventry CV4 7AL, United Kingdom
| | - Yanling Tian
- School of Engineering, University of Warwick, Coventry CV4 7AL, United Kingdom
| | - Liguo Tian
- Ministry of Education Key Laboratory for Cross-Scale Micro and Nano Manufacturing, Changchun University of Science and Technology, Changchun 130022, China
- International Research Centre for Nano Handling and Manufacturing of China, Changchun University of Science and Technology, Changchun 130022, China
| | - Zuobin Wang
- Ministry of Education Key Laboratory for Cross-Scale Micro and Nano Manufacturing, Changchun University of Science and Technology, Changchun 130022, China
- International Research Centre for Nano Handling and Manufacturing of China, Changchun University of Science and Technology, Changchun 130022, China
| | - Xianping Liu
- School of Engineering, University of Warwick, Coventry CV4 7AL, United Kingdom
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7
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Lin L, Wang X, Li C, Cui H. Inactivation mechanism of E. coli O157:H7 under ultrasonic sterilization. ULTRASONICS SONOCHEMISTRY 2019; 59:104751. [PMID: 31473421 DOI: 10.1016/j.ultsonch.2019.104751] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Revised: 08/17/2019] [Accepted: 08/23/2019] [Indexed: 05/09/2023]
Abstract
Ultrasonic sterilization (US), as a promising non-thermal sterilization method, exhibits unique superiorities than traditional sterilization methods. In this study, the inactivation mechanism of E. coli O157:H7 under US was investigated in cucumber and bitter gourd vegetable juices. Results revealed that the US treatment showed good antibacterial ability in countering E. coli O157:H7. Through determinations of conductivity and β-galactosidase activity, significant augmentation in membrane permeability of the bacteria was confirmed after the US treatment. The morphologies of the US treated E. coli O157:H7 demonstrated that the integrity of the cell membrane was disrupted by US treatment. SDS-PAGE and LSCM data further proved the disruptive action of US, leading to the leakage of proteins and DNA through the breakage on cell membrane. The decrease of metabolic-related enzyme activity was verified through investigation of bacterial metabolism. The antibacterial mechanism analysis indicated that the US can generate free radicals which resulted in the rise of intracellular oxidative stress, attenuation of energy metabolism and inhibition of hexose monophosphate pathway. As the application verification, the US treatment can cause the deprivation of E. coli O157:H7 cell viability in vegetable juices without obvious impact on the sensory quality.
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Affiliation(s)
- Lin Lin
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang 212013, China
| | - Xinlei Wang
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang 212013, China
| | - Changzhu Li
- Department of Bioresource, Hunan Academy of Forestry, Changsha 410007, China
| | - Haiying Cui
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang 212013, China.
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8
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Wang D, Ma B, Zhao Y, Sun Y, Luan Y, Wang J. Preparation and Properties of Semi-Self-Assembled Lipopeptide Vesicles. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:13174-13181. [PMID: 31532218 DOI: 10.1021/acs.langmuir.9b02513] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Novel lipopeptide vesicles are prepared from self-assembled nanomembranes through an extrusion method. The size of vesicles can be controlled by the pore diameter of the extrusion filter. The vesicles are rather stable because hydrogen bonds exist among the peptide headgroups. When doxorubicin hydrochloride (DOX·HCl) is encapsulated in the vesicles, it could be released sustainably, and its side effect would also be reduced due to encapsulation. The leakage rate of DOX·HCl depends on the pH via charge regulation. As drug carriers, lipopeptide vesicles have been proved to have nontoxicity to normal cells. A magnetic surfactant CH3(CH2)14CH2N(CH3)3+ [FeCl3Br]- (CTAFe) was mixed with lipopeptide to modify the vesicles. Also, the results demonstrated that the vesicles is endowed with magnetic property after the addition of CTAFe. We believe that the strategy of lipopeptide vesicle preparation would enrich the drug carrier family and expand the application of lipopeptide materials.
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Affiliation(s)
- Dong Wang
- State Key Laboratory of Heavy Oil Processing and Centre for Bioengineering and Biotechnology , China University of Petroleum (East China) , Qingdao 266580 , China
| | - Bente Ma
- State Key Laboratory of Heavy Oil Processing and Centre for Bioengineering and Biotechnology , China University of Petroleum (East China) , Qingdao 266580 , China
| | - Yurong Zhao
- State Key Laboratory of Heavy Oil Processing and Centre for Bioengineering and Biotechnology , China University of Petroleum (East China) , Qingdao 266580 , China
| | - Yawei Sun
- State Key Laboratory of Heavy Oil Processing and Centre for Bioengineering and Biotechnology , China University of Petroleum (East China) , Qingdao 266580 , China
| | - Yuxia Luan
- School of Pharmaceutical Science, Key Laboratory of Chemical Biology (Ministry of Education) , Shandong University , 44 West Wenhua Road , Jinan , Shandong 250012 , China
| | - Jiqian Wang
- State Key Laboratory of Heavy Oil Processing and Centre for Bioengineering and Biotechnology , China University of Petroleum (East China) , Qingdao 266580 , China
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9
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Hu J, Jiao J, Wang Y, Gao M, Lu Z, Yang F, Hu C, Song Z, Chen Y, Wang Z. Effect of extract from ginseng rust rot on the inhibition of human hepatocellular carcinoma cells in vitro. Micron 2019; 124:102710. [PMID: 31280008 DOI: 10.1016/j.micron.2019.102710] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Revised: 06/28/2019] [Accepted: 07/01/2019] [Indexed: 01/04/2023]
Abstract
Hepatocellular carcinoma (HCC) is one of major leading causes of cancer death worldwide. As a traditional medicine, the anti-cancer function of ginseng is being growingly recognized and investigated. However, the effect of ginseng rust rot on human HCC is unknown yet. In this study, the HCC cells were treated with different parts of mountain cultivated ginseng rust rot and compared with human normal liver cells. The morphology, survival rate and β-actin expression of the cells were changed by introducing the ginseng epidermis during the incubation process. Notably, the results reveal that the ginseng epidermis can induce apoptosis by altering the morphologies of cells, indicating the practical implication for the HCC treatment and drug development.
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Affiliation(s)
- Jing Hu
- Ministry of Education Key Laboratory for Cross-Scale Micro and Nano Manufacturing, Changchun University of Science and Technology, Changchun 130022, China; International Research Centre for Nano Handling and Manufacturing of China, Changchun University of Science and Technology, Changchun 130022, China
| | - Jie Jiao
- Ministry of Education Key Laboratory for Cross-Scale Micro and Nano Manufacturing, Changchun University of Science and Technology, Changchun 130022, China; International Research Centre for Nano Handling and Manufacturing of China, Changchun University of Science and Technology, Changchun 130022, China; School of Life Sciences, Changchun University of Science and Technology, Changchun 130022, China
| | - Ying Wang
- Ministry of Education Key Laboratory for Cross-Scale Micro and Nano Manufacturing, Changchun University of Science and Technology, Changchun 130022, China; International Research Centre for Nano Handling and Manufacturing of China, Changchun University of Science and Technology, Changchun 130022, China
| | - Mingyan Gao
- Ministry of Education Key Laboratory for Cross-Scale Micro and Nano Manufacturing, Changchun University of Science and Technology, Changchun 130022, China; International Research Centre for Nano Handling and Manufacturing of China, Changchun University of Science and Technology, Changchun 130022, China
| | - Zhengcheng Lu
- JR3CN & IRAC, University of Bedfordshire, Luton LU1 3JU, UK
| | - Fan Yang
- Ministry of Education Key Laboratory for Cross-Scale Micro and Nano Manufacturing, Changchun University of Science and Technology, Changchun 130022, China; International Research Centre for Nano Handling and Manufacturing of China, Changchun University of Science and Technology, Changchun 130022, China
| | - Cuihua Hu
- Ministry of Education Key Laboratory for Cross-Scale Micro and Nano Manufacturing, Changchun University of Science and Technology, Changchun 130022, China; International Research Centre for Nano Handling and Manufacturing of China, Changchun University of Science and Technology, Changchun 130022, China
| | - Zhengxun Song
- Ministry of Education Key Laboratory for Cross-Scale Micro and Nano Manufacturing, Changchun University of Science and Technology, Changchun 130022, China; International Research Centre for Nano Handling and Manufacturing of China, Changchun University of Science and Technology, Changchun 130022, China
| | - Yujuan Chen
- Ministry of Education Key Laboratory for Cross-Scale Micro and Nano Manufacturing, Changchun University of Science and Technology, Changchun 130022, China; International Research Centre for Nano Handling and Manufacturing of China, Changchun University of Science and Technology, Changchun 130022, China; School of Life Sciences, Changchun University of Science and Technology, Changchun 130022, China.
| | - Zuobin Wang
- Ministry of Education Key Laboratory for Cross-Scale Micro and Nano Manufacturing, Changchun University of Science and Technology, Changchun 130022, China; International Research Centre for Nano Handling and Manufacturing of China, Changchun University of Science and Technology, Changchun 130022, China; JR3CN & IRAC, University of Bedfordshire, Luton LU1 3JU, UK.
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10
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Li Q, Li C, Mu W, Han X. Topological Defect-Driven Buckling of Phospholipid Bicelles to Cones for Micromotors with Modulated Heading Pathways. ACS NANO 2019; 13:3573-3579. [PMID: 30855945 DOI: 10.1021/acsnano.9b00086] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Topological defects are crucial to the shaping of the crystalline membrane systems such as lipid bilayers, virus capsids, and graphene as well as the arrangement of cells in tissues. In a typical case, the introduction of disclination defects elastically buckles the crystalline membranes into conical shapes. However, how planar membranes transform to cones triggered by disclinations is still rarely observed in the experiments. Herein, we experimentally observe the transformation from phospholipid bicelles to cones in response to disclinations. During the transformation process, the wall thickness increases, while the conical generatrix length remains the same with respect to the radius of bicelles. The cones with apex angles of 112.8°, 83.6°, 60°, 39°, and 19.2° are observed when 1, 2, 3, 4, and 5 pentagon defects are introduced, respectively. Monodispersed microcones are obtained by adjusting aging temperature and time. These microcones are then used as templates to form platinum conical micromotors with open tips or closed tips, which display different heading directions in H2O2 solution. Our work provides a shape evolution pathway of planar membranes in response to disclinations. The homogeneous microcones can find wide applications in micromotors fabrication, the study of curvature-dependent processes, and the formation of advanced materials.
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Affiliation(s)
- Qingchuan Li
- State Key Laboratory of Urban Water Resource and Environment, School of Chemistry and Chemical Engineering , Harbin Institute of Technology , 92 West Da-Zhi Street , Harbin 150001 , China
| | - Chao Li
- State Key Laboratory of Urban Water Resource and Environment, School of Chemistry and Chemical Engineering , Harbin Institute of Technology , 92 West Da-Zhi Street , Harbin 150001 , China
| | - Wei Mu
- State Key Laboratory of Urban Water Resource and Environment, School of Chemistry and Chemical Engineering , Harbin Institute of Technology , 92 West Da-Zhi Street , Harbin 150001 , China
| | - Xiaojun Han
- State Key Laboratory of Urban Water Resource and Environment, School of Chemistry and Chemical Engineering , Harbin Institute of Technology , 92 West Da-Zhi Street , Harbin 150001 , China
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11
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Afrin R, Ganbaatar N, Aono M, Cleaves Ii HJ, Yano TA, Hara M. Size-Dependent Affinity of Glycine and Its Short Oligomers to Pyrite Surface: A Model for Prebiotic Accumulation of Amino Acid Oligomers on a Mineral Surface. Int J Mol Sci 2018; 19:ijms19020365. [PMID: 29370126 PMCID: PMC5855587 DOI: 10.3390/ijms19020365] [Citation(s) in RCA: 3] [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: 11/30/2017] [Revised: 12/23/2017] [Accepted: 12/23/2017] [Indexed: 11/16/2022] Open
Abstract
The interaction strength of progressively longer oligomers of glycine, (Gly), di-Gly, tri-Gly, and penta-Gly, with a natural pyrite surface was directly measured using the force mode of an atomic force microscope (AFM). In recent years, selective activation of abiotically formed amino acids on mineral surfaces, especially that of pyrite, has been proposed as an important step in many origins of life scenarios. To investigate such notions, we used AFM-based force measurements to probe possible non-covalent interactions between pyrite and amino acids, starting from the simplest amino acid, Gly. Although Gly itself interacted with the pyrite surface only weakly, progressively larger unbinding forces and binding frequencies were obtained using oligomers from di-Gly to penta-Gly. In addition to an expected increase of the configurational entropy and size-dependent van der Waals force, the increasing number of polar peptide bonds, among others, may be responsible for this observation. The effect of chain length was also investigated by performing similar experiments using l-lysine vs. poly-l-lysine (PLL), and l-glutamic acid vs. poly-l-glutamic acid. The results suggest that longer oligomers/polymers of amino acids can be preferentially adsorbed on pyrite surfaces.
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Affiliation(s)
- Rehana Afrin
- Chemical Evolution Lab Unit, Earth-Life Science Institute (ELSI), Tokyo Institute of Technology, 2-12-1-IE-1 Ookayama, Meguro-ku, Tokyo 152-8550, Japan.
| | - Narangerel Ganbaatar
- Chemical Evolution Lab Unit, Earth-Life Science Institute (ELSI), Tokyo Institute of Technology, 2-12-1-IE-1 Ookayama, Meguro-ku, Tokyo 152-8550, Japan.
- School of Materials and Chemical Technology, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama 226-8502, Japan.
| | - Masashi Aono
- Chemical Evolution Lab Unit, Earth-Life Science Institute (ELSI), Tokyo Institute of Technology, 2-12-1-IE-1 Ookayama, Meguro-ku, Tokyo 152-8550, Japan.
- Faculty of Environment and Information Studies, Keio University, 5322 Endo, Fujisawa-shi, Kanagawa 252-0882, Japan.
| | - H James Cleaves Ii
- Chemical Evolution Lab Unit, Earth-Life Science Institute (ELSI), Tokyo Institute of Technology, 2-12-1-IE-1 Ookayama, Meguro-ku, Tokyo 152-8550, Japan.
| | - Taka-Aki Yano
- Chemical Evolution Lab Unit, Earth-Life Science Institute (ELSI), Tokyo Institute of Technology, 2-12-1-IE-1 Ookayama, Meguro-ku, Tokyo 152-8550, Japan.
- School of Materials and Chemical Technology, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama 226-8502, Japan.
| | - Masahiko Hara
- Chemical Evolution Lab Unit, Earth-Life Science Institute (ELSI), Tokyo Institute of Technology, 2-12-1-IE-1 Ookayama, Meguro-ku, Tokyo 152-8550, Japan.
- School of Materials and Chemical Technology, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama 226-8502, Japan.
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12
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Tian R, Luo M, Li J. Spontaneous protein desorption from self-assembled monolayer (SAM)-coated gold nanoparticles. Phys Chem Chem Phys 2018; 20:68-74. [DOI: 10.1039/c7cp05515c] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Interfacial water molecules and lateral diffusion of protein reduce the adsorption affinity of protein and promote protein desorption.
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Affiliation(s)
- Ranran Tian
- Department of Physics
- Zhejiang University
- Hangzhou
- China
| | - Mengbo Luo
- Department of Physics
- Zhejiang University
- Hangzhou
- China
| | - Jingyuan Li
- Department of Physics
- Zhejiang University
- Hangzhou
- China
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13
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de Moura KS, da Silva HRC, Dornelles LP, Coelho LCBB, Napoleão TH, de Oliveira MDL, Paiva PMG. Coagulant Activity of Water-Soluble Moringa oleifera Lectin Is Linked to Lowering of Electrical Resistance and Inhibited by Monosaccharides and Magnesium Ions. Appl Biochem Biotechnol 2016; 180:1361-1371. [DOI: 10.1007/s12010-016-2172-y] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2015] [Accepted: 06/20/2016] [Indexed: 11/25/2022]
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14
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Highly Sensitive Homogeneous Immunoassays Based on Construction of Silver Triangular Nanoplates-Quantum Dots FRET System. Sci Rep 2016; 6:26534. [PMID: 27198713 PMCID: PMC4873782 DOI: 10.1038/srep26534] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Accepted: 05/03/2016] [Indexed: 01/09/2023] Open
Abstract
With growing concerns about health issues worldwide, elegant sensors with high sensitivity and specificity for virus/antigens (Ag) detection are urgent to be developed. Homogeneous immunoassays (HIA) are an important technique with the advantages of small sample volumes requirement and pretreatment-free process. HIA are becoming more favorable for the medical diagnosis and disease surveillance than heterogeneous immunoassays. An important subset of HIA relies on the effect of fluorescence resonance energy transfer (FRET) via a donor-acceptor (D-A) platform, e.g., quantum dots (QDs) donor based FRET system. Being an excellent plasmonic material, silver triangular nanoplates (STNPs) have unique advantages in displaying surface plasmon resonance in the visible to near infrared spectral region, which make them a better acceptor for pairing with QDs in a FRET-based sensing system. However, the reported STNPs generally exhibited broad size distributions, which would greatly restrict their application as HIA acceptor for high detection sensitivity and specificity purpose. In this work, uniform STNPs and red-emitting QDs are firstly applied to construct FRET nanoplatform in the advanced HIA and further be exploited for analyzing virus Ag. The uniform STNPs/QDs nanoplatform based medical sensor provides a straightforward and highly sensitive method for Ag analysis in homogeneous form.
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Human lectins and their roles in viral infections. Molecules 2015; 20:2229-71. [PMID: 25642836 PMCID: PMC6272597 DOI: 10.3390/molecules20022229] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2014] [Revised: 01/21/2015] [Accepted: 01/23/2015] [Indexed: 12/20/2022] Open
Abstract
Innate recognition of virus proteins is an important component of the immune response to viral pathogens. A component of this immune recognition is the family of lectins; pattern recognition receptors (PRRs) that recognise viral pathogen-associated molecular patterns (PAMPs) including viral glycoproteins. In this review we discuss the contribution of soluble and membrane-associated PRRs to immunity against virus pathogens, and the potential role of these molecules in facilitating virus replication. These processes are illustrated with examples of viruses including human immunodeficiency virus (HIV), hepatitis C virus (HCV) and Ebola virus (EBOV). We focus on the structure, function and genetics of the well-characterised C-type lectin mannose-binding lectin, the ficolins, and the membrane-bound CD209 proteins expressed on dendritic cells. The potential for lectin-based antiviral therapies is also discussed.
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16
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Small-angle X-ray scattering to obtain models of multivalent lectin-glycan complexes. Methods Mol Biol 2014; 1200:511-26. [PMID: 25117261 DOI: 10.1007/978-1-4939-1292-6_42] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Recent advances in small-angle X-ray scattering (SAXS) have led to the ability to model the glycans on glycoproteins and to obtain the low-resolution solution structures of complexes of lectins bound to multivalent glycan-presenting scaffolds. This progress in SAXS can respond to the increasing interest in the biological action of glycoproteins and lectins and in the design of multivalent glycan-based antagonists. Carbohydrates make up a significant part of the X-ray scattering content in SAXS and should be included in the model together with the protein, whose structure is most often based on a crystal structure or NMR ensemble, to give a far-improved fit with the experimental data. The modeling of the spatial positioning of glycans on proteins or in the architecture of lectin-glycan complexes delivers low-resolution structural information hitherto unmatched by any other method. SAXS data on the bacterial lectin FimH, strongly bound to heptyl α-D-mannose on a sevenfold derivatized β-cyclodextrin, permitted determination of the stoichiometry of the complex and the geometry of the lectin deposition on the multivalent β-cyclodextrin. The SAXS methods can be applied to larger complexes as the technique imposes no limit on the size of the macromolecular assembly in solution.
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17
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Degn SE, Thiel S. Humoral Pattern Recognition and the Complement System. Scand J Immunol 2013; 78:181-93. [DOI: 10.1111/sji.12070] [Citation(s) in RCA: 103] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2013] [Accepted: 05/13/2013] [Indexed: 12/16/2022]
Affiliation(s)
- S. E. Degn
- Department of Biomedicine; Aarhus University; Aarhus; Denmark
| | - S. Thiel
- Department of Biomedicine; Aarhus University; Aarhus; Denmark
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18
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Brudner M, Karpel M, Lear C, Chen L, Yantosca LM, Scully C, Sarraju A, Sokolovska A, Zariffard MR, Eisen DP, Mungall BA, Kotton DN, Omari A, Huang IC, Farzan M, Takahashi K, Stuart L, Stahl GL, Ezekowitz AB, Spear GT, Olinger GG, Schmidt EV, Michelow IC. Lectin-dependent enhancement of Ebola virus infection via soluble and transmembrane C-type lectin receptors. PLoS One 2013; 8:e60838. [PMID: 23573288 PMCID: PMC3614905 DOI: 10.1371/journal.pone.0060838] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2011] [Accepted: 03/05/2013] [Indexed: 01/19/2023] Open
Abstract
Mannose-binding lectin (MBL) is a key soluble effector of the innate immune system that recognizes pathogen-specific surface glycans. Surprisingly, low-producing MBL genetic variants that may predispose children and immunocompromised individuals to infectious diseases are more common than would be expected in human populations. Since certain immune defense molecules, such as immunoglobulins, can be exploited by invasive pathogens, we hypothesized that MBL might also enhance infections in some circumstances. Consequently, the low and intermediate MBL levels commonly found in human populations might be the result of balancing selection. Using model infection systems with pseudotyped and authentic glycosylated viruses, we demonstrated that MBL indeed enhances infection of Ebola, Hendra, Nipah and West Nile viruses in low complement conditions. Mechanistic studies with Ebola virus (EBOV) glycoprotein pseudotyped lentiviruses confirmed that MBL binds to N-linked glycan epitopes on viral surfaces in a specific manner via the MBL carbohydrate recognition domain, which is necessary for enhanced infection. MBL mediates lipid-raft-dependent macropinocytosis of EBOV via a pathway that appears to require less actin or early endosomal processing compared with the filovirus canonical endocytic pathway. Using a validated RNA interference screen, we identified C1QBP (gC1qR) as a candidate surface receptor that mediates MBL-dependent enhancement of EBOV infection. We also identified dectin-2 (CLEC6A) as a potentially novel candidate attachment factor for EBOV. Our findings support the concept of an innate immune haplotype that represents critical interactions between MBL and complement component C4 genes and that may modify susceptibility or resistance to certain glycosylated pathogens. Therefore, higher levels of native or exogenous MBL could be deleterious in the setting of relative hypocomplementemia which can occur genetically or because of immunodepletion during active infections. Our findings confirm our hypothesis that the pressure of infectious diseases may have contributed in part to evolutionary selection of MBL mutant haplotypes.
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Affiliation(s)
- Matthew Brudner
- Programs of Developmental Immunology, Department of Pediatrics, Massachusetts General Hospital, Boston, Massachusetts, United States of America
| | - Marshall Karpel
- Programs of Developmental Immunology, Department of Pediatrics, Massachusetts General Hospital, Boston, Massachusetts, United States of America
| | - Calli Lear
- Virology Division, United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, Frederick, Maryland, United States of America
| | - Li Chen
- Programs of Developmental Immunology, Department of Pediatrics, Massachusetts General Hospital, Boston, Massachusetts, United States of America
| | - L. Michael Yantosca
- Programs of Developmental Immunology, Department of Pediatrics, Massachusetts General Hospital, Boston, Massachusetts, United States of America
| | - Corinne Scully
- Virology Division, United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, Frederick, Maryland, United States of America
| | - Ashish Sarraju
- Programs of Developmental Immunology, Department of Pediatrics, Massachusetts General Hospital, Boston, Massachusetts, United States of America
| | - Anna Sokolovska
- Programs of Developmental Immunology, Department of Pediatrics, Massachusetts General Hospital, Boston, Massachusetts, United States of America
| | - M. Reza Zariffard
- Department of Immunology and Microbiology, Rush University Medical Center, Chicago, Illinois, United States of America
| | - Damon P. Eisen
- Victorian Infectious Diseases Service, Royal Melbourne Hospital, Parkville, Victoria, Australia
| | - Bruce A. Mungall
- Australian Animal Health Laboratory, Commonwealth Scientific and Industrial Research Organisation (CSIRO) Livestock Industries, Geelong, Victoria, Australia
| | - Darrell N. Kotton
- Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, United States of America
| | - Amel Omari
- Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, United States of America
| | - I-Chueh Huang
- New England Primate Research Center, Southborough, Massachusetts, United States of America
| | - Michael Farzan
- New England Primate Research Center, Southborough, Massachusetts, United States of America
- Harvard Medical School, Boston, Massachusetts, United States of America
| | - Kazue Takahashi
- Programs of Developmental Immunology, Department of Pediatrics, Massachusetts General Hospital, Boston, Massachusetts, United States of America
- Harvard Medical School, Boston, Massachusetts, United States of America
| | - Lynda Stuart
- Programs of Developmental Immunology, Department of Pediatrics, Massachusetts General Hospital, Boston, Massachusetts, United States of America
- Harvard Medical School, Boston, Massachusetts, United States of America
| | - Gregory L. Stahl
- CETRI, Brigham and Women's Hospital, Boston, Massachusetts, United States of America
- Harvard Medical School, Boston, Massachusetts, United States of America
| | - Alan B. Ezekowitz
- Programs of Developmental Immunology, Department of Pediatrics, Massachusetts General Hospital, Boston, Massachusetts, United States of America
| | - Gregory T. Spear
- Department of Immunology and Microbiology, Rush University Medical Center, Chicago, Illinois, United States of America
| | - Gene G. Olinger
- Virology Division, United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, Frederick, Maryland, United States of America
| | - Emmett V. Schmidt
- Programs of Developmental Immunology, Department of Pediatrics, Massachusetts General Hospital, Boston, Massachusetts, United States of America
- Harvard Medical School, Boston, Massachusetts, United States of America
- * E-mail: (EVS); (ICM)
| | - Ian C. Michelow
- Programs of Developmental Immunology, Department of Pediatrics, Massachusetts General Hospital, Boston, Massachusetts, United States of America
- Harvard Medical School, Boston, Massachusetts, United States of America
- * E-mail: (EVS); (ICM)
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Jacquet M, Lacroix M, Ancelet S, Gout E, Gaboriaud C, Thielens NM, Rossi V. Deciphering complement receptor type 1 interactions with recognition proteins of the lectin complement pathway. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2013; 190:3721-31. [PMID: 23460739 DOI: 10.4049/jimmunol.1202451] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Complement receptor type 1 (CR1) is a membrane receptor expressed on a wide range of cells. It is involved in immune complex clearance, phagocytosis, and complement regulation. Its ectodomain is composed of 30 complement control protein (CCP) modules, organized into four long homologous repeats (A-D). In addition to its main ligands C3b and C4b, CR1 was reported to interact with C1q and mannan-binding lectin (MBL) likely through its C-terminal region (CCP22-30). To decipher the interaction of human CR1 with the recognition proteins of the lectin complement pathway, a recombinant fragment encompassing CCP22-30 was expressed in eukaryotic cells, and its interaction with human MBL and ficolins was investigated using surface plasmon resonance spectroscopy. MBL and L-ficolin were shown to interact with immobilized soluble CR1 and CR1 CCP22-30 with apparent dissociation constants in the nanomolar range, indicative of high affinity. The binding site for CR1 was located at or near the MBL-associated serine protease (MASP) binding site in the collagen stalks of MBL and L-ficolin, as shown by competition experiments with MASP-3. Accordingly, the mutation of an MBL conserved lysine residue essential for MASP binding (K55) abolished binding to soluble CR1 and CCP22-30. The CR1 binding site for MBL/ficolins was mapped to CCP24-25 of long homologous repeat D using deletion mutants. In conclusion, we show that ficolins are new CR1 ligands and propose that MBL/L-ficolin binding involves major ionic interactions between conserved lysine residues of their collagen stalks and surface exposed acidic residues located in CR1 CCP24 and/or CCP25.
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Affiliation(s)
- Mickaël Jacquet
- Commissariat à l'Energie Atomique, Institut de Biologie Structurale Jean-Pierre Ebel, 38027 Grenoble Cedex 1, France
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20
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Vorup-Jensen T. On the roles of polyvalent binding in immune recognition: perspectives in the nanoscience of immunology and the immune response to nanomedicines. Adv Drug Deliv Rev 2012; 64:1759-81. [PMID: 22705545 DOI: 10.1016/j.addr.2012.06.003] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2012] [Revised: 06/06/2012] [Accepted: 06/08/2012] [Indexed: 12/31/2022]
Abstract
Immunology often conveys the image of large molecules, either in the soluble state or in the membrane of leukocytes, forming multiple contacts with a target for actions of the immune system. Avidity names the ability of a polyvalent molecule to form multiple connections of the same kind with ligands tethered to the same surface. Polyvalent interactions are vastly stronger than their monovalent equivalent. In the present review, the functional consequences of polyvalent interactions are explored in a perspective of recent theoretical advances in understanding the thermodynamics of such binding. From insights on the structural biology of soluble pattern recognition molecules as well as adhesion molecules in the cell membranes or in their proteolytically shed form, this review documents the prominent role of polyvalent interactions in making the immune system a formidable barrier to microbial infection as well as constituting a significant challenge to the application of nanomedicines.
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21
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Structure and function of collectin liver 1 (CL-L1) and collectin 11 (CL-11, CL-K1). Immunobiology 2012; 217:851-63. [DOI: 10.1016/j.imbio.2011.12.008] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2011] [Revised: 12/16/2011] [Accepted: 12/16/2011] [Indexed: 01/25/2023]
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22
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Miller A, Phillips A, Gor J, Wallis R, Perkins SJ. Near-planar solution structures of mannose-binding lectin oligomers provide insight on activation of lectin pathway of complement. J Biol Chem 2012; 287:3930-45. [PMID: 22167201 PMCID: PMC3281675 DOI: 10.1074/jbc.m111.320341] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2011] [Revised: 12/01/2011] [Indexed: 12/03/2022] Open
Abstract
The complement system is a fundamental component of innate immunity that orchestrates complex immunological and inflammatory processes. Complement comprises over 30 proteins that eliminate invading microorganisms while maintaining host cell integrity. Protein-carbohydrate interactions play critical roles in both the activation and regulation of complement. Mannose-binding lectin (MBL) activates the lectin pathway of complement via the recognition of sugar arrays on pathogenic surfaces. To determine the solution structure of MBL, synchrotron x-ray scattering and analytical ultracentrifugation experiments showed that the carbohydrate-recognition domains in the MBL dimer, trimer, and tetramer are positioned close to each other in near-planar fan-like structures. These data were subjected to constrained modeling fits. A bent structure for the MBL monomer was identified starting from two crystal structures for its carbohydrate-recognition domain and its triple helical region. The MBL monomer structure was used to identify 10-12 near-planar solution structures for each of the MBL dimers, trimers, and tetramers starting from 900 to 6,859 randomized structures for each. These near-planar fan-like solution structures joined at an N-terminal hub clarified how the carbohydrate-recognition domain of MBL binds to pathogenic surfaces. They also provided insight on how MBL presents a structural template for the binding and auto-activation of the MBL-associated serine proteases to initiate the lectin pathway of complement activation.
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Affiliation(s)
- Ami Miller
- From the Department of Structural and Molecular Biology, Darwin Building, University College London, Gower Street, London, WC1E 6BT and
| | - Anna Phillips
- the Department of Infection, Immunity, and Inflammation, Medical Science Building, University of Leicester, University Road, Leicester, LE1 9HN, United Kingdom
| | - Jayesh Gor
- From the Department of Structural and Molecular Biology, Darwin Building, University College London, Gower Street, London, WC1E 6BT and
| | - Russell Wallis
- the Department of Infection, Immunity, and Inflammation, Medical Science Building, University of Leicester, University Road, Leicester, LE1 9HN, United Kingdom
| | - Stephen J. Perkins
- From the Department of Structural and Molecular Biology, Darwin Building, University College London, Gower Street, London, WC1E 6BT and
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23
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Gjelstrup LC, Kaspersen JD, Behrens MA, Pedersen JS, Thiel S, Kingshott P, Oliveira CLP, Thielens NM, Vorup-Jensen T. The role of nanometer-scaled ligand patterns in polyvalent binding by large mannan-binding lectin oligomers. THE JOURNAL OF IMMUNOLOGY 2012; 188:1292-306. [PMID: 22219330 DOI: 10.4049/jimmunol.1103012] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Mannan-binding lectin (MBL) is an important protein of the innate immune system and protects the body against infection through opsonization and activation of the complement system on surfaces with an appropriate presentation of carbohydrate ligands. The quaternary structure of human MBL is built from oligomerization of structural units into polydisperse complexes typically with three to eight structural units, each containing three lectin domains. Insight into the connection between the structure and ligand-binding properties of these oligomers has been lacking. In this article, we present an analysis of the binding to neoglycoprotein-coated surfaces by size-fractionated human MBL oligomers studied with small-angle x-ray scattering and surface plasmon resonance spectroscopy. The MBL oligomers bound to these surfaces mainly in two modes, with dissociation constants in the micro to nanomolar order. The binding kinetics were markedly influenced by both the density of ligands and the number of ligand-binding domains in the oligomers. These findings demonstrated that the MBL-binding kinetics are critically dependent on structural characteristics on the nanometer scale, both with regard to the dimensions of the oligomer, as well as the ligand presentation on surfaces. Therefore, our work suggested that the surface binding of MBL involves recognition of patterns with dimensions on the order of 10-20 nm. The recent understanding that the surfaces of many microbes are organized with structural features on the nanometer scale suggests that these properties of MBL ligand recognition potentially constitute an important part of the pattern-recognition ability of these polyvalent oligomers.
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Affiliation(s)
- Louise C Gjelstrup
- Biophysical Immunology Laboratory, Aarhus University, DK-8000 Aarhus C, Denmark
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24
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Liu P, Zhang S, Chen MS, Liu Q, Wang C, Wang C, Li YM, Besenbacher F, Dong M. Co-assembly of human islet amyloid polypeptide (hIAPP)/insulin. Chem Commun (Camb) 2012; 48:191-3. [DOI: 10.1039/c1cc14285b] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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25
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Heitzeneder S, Seidel M, Förster-Waldl E, Heitger A. Mannan-binding lectin deficiency - Good news, bad news, doesn't matter? Clin Immunol 2011; 143:22-38. [PMID: 22377282 DOI: 10.1016/j.clim.2011.11.002] [Citation(s) in RCA: 123] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2011] [Revised: 11/03/2011] [Accepted: 11/04/2011] [Indexed: 01/13/2023]
Abstract
Mannan-binding lectin (MBL) deficiency has been classified as a commonly occurring immune disorder, affecting approximately 30% of the human population. MBL, being part of the innate immune system, supports the recognition of infectious pathogens by binding to carbohydrate moieties expressed on microorganisms and activates the lectin pathway of the complement system. MBL2 gene polymorphisms are associated with quantitative and qualitative MBL abnormalities in the serum. The clinical impact of MBL deficiency and its association to a wide variety of diseases has been extensively studied. The picture is puzzling as the studies suggest a detrimental or beneficial or no impact of low or high MBL serum levels on disease susceptibility. In this review we attempt to extract what is relevant from the literature and address controversial issues. We finally suggest that a comprehensive understanding of the role of MBL in human diseases requires considering its context-dependency.
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26
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Protein ultrastructure and the nanoscience of complement activation. Adv Drug Deliv Rev 2011; 63:1008-19. [PMID: 21699938 DOI: 10.1016/j.addr.2011.05.023] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2011] [Accepted: 05/31/2011] [Indexed: 12/24/2022]
Abstract
The complement system constitutes an important barrier to infection of the human body. Over more than four decades structural properties of the proteins of the complement system have been investigated with X-ray crystallography, electron microscopy, small-angle scattering, and atomic force microscopy. Here, we review the accumulated evidence that the nm-scaled dimensions and conformational changes of these proteins support functions of the complement system with regard to tissue distribution, molecular crowding effects, avidity binding, and conformational regulation of complement activation. In the targeting of complement activation to the surfaces of nanoparticulate material, such as engineered nanoparticles or fragments of the microbial cell wall, these processes play intimately together. This way the complement system is an excellent example where nanoscience may serve to unravel the molecular biology of the immune response.
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27
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Michelow IC, Dong M, Mungall BA, Yantosca LM, Lear C, Ji X, Karpel M, Rootes CL, Brudner M, Houen G, Eisen DP, Kinane TB, Takahashi K, Stahl GL, Olinger GG, Spear GT, Ezekowitz RAB, Schmidt EV. A novel L-ficolin/mannose-binding lectin chimeric molecule with enhanced activity against Ebola virus. J Biol Chem 2010; 285:24729-39. [PMID: 20516066 PMCID: PMC2915709 DOI: 10.1074/jbc.m110.106260] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2010] [Revised: 05/28/2010] [Indexed: 12/21/2022] Open
Abstract
Ebola viruses constitute a newly emerging public threat because they cause rapidly fatal hemorrhagic fevers for which no treatment exists, and they can be manipulated as bioweapons. We targeted conserved N-glycosylated carbohydrate ligands on viral envelope surfaces using novel immune therapies. Mannose-binding lectin (MBL) and L-ficolin (L-FCN) were selected because they function as opsonins and activate complement. Given that MBL has a complex quaternary structure unsuitable for large scale cost-effective production, we sought to develop a less complex chimeric fusion protein with similar ligand recognition and enhanced effector functions. We tested recombinant human MBL and three L-FCN/MBL variants that contained the MBL carbohydrate recognition domain and varying lengths of the L-FCN collagenous domain. Non-reduced chimeric proteins formed predominantly nona- and dodecameric oligomers, whereas recombinant human MBL formed octadecameric and larger oligomers. Surface plasmon resonance revealed that L-FCN/MBL76 had the highest binding affinities for N-acetylglucosamine-bovine serum albumin and mannan. The same chimeric protein displayed superior complement C4 cleavage and binding to calreticulin (cC1qR), a putative receptor for MBL. L-FCN/MBL76 reduced infection by wild type Ebola virus Zaire significantly greater than the other molecules. Tapping mode atomic force microscopy revealed that L-FCN/MBL76 was significantly less tall than the other molecules despite similar polypeptide lengths. We propose that alterations in the quaternary structure of L-FCN/MBL76 resulted in greater flexibility in the collagenous or neck region. Similarly, a more pliable molecule might enhance cooperativity between the carbohydrate recognition domains and their cognate ligands, complement activation, and calreticulin binding dynamics. L-FCN/MBL chimeric proteins should be considered as potential novel therapeutics.
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Affiliation(s)
- Ian C. Michelow
- From the Program of Developmental Immunology, Department of Pediatrics, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114
| | - Mingdong Dong
- Interdisciplinary Nanoscience Center (iNANO), University of Aarhus, DK-8000 Aarhus, Denmark
| | - Bruce A. Mungall
- Australian Animal Health Laboratory, Commonwealth Scientific and Industrial Research Organisation (CSIRO) Livestock Industries, Geelong, Victoria 3220, Australia
| | - L. Michael Yantosca
- From the Program of Developmental Immunology, Department of Pediatrics, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114
| | - Calli Lear
- Virology Division, United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, Frederick, Maryland 21702
| | - Xin Ji
- Department of Immunology/Microbiology, Rush University Medical Center, Chicago, Illinois 60612
| | - Marshall Karpel
- From the Program of Developmental Immunology, Department of Pediatrics, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114
| | - Christina L. Rootes
- Australian Animal Health Laboratory, Commonwealth Scientific and Industrial Research Organisation (CSIRO) Livestock Industries, Geelong, Victoria 3220, Australia
| | - Matthew Brudner
- From the Program of Developmental Immunology, Department of Pediatrics, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114
| | - Gunnar Houen
- Department of Clinical Biochemistry and Immunology, Statens Serum Institut, DK-2300 Copenhagen, Denmark
| | - Damon P. Eisen
- Victorian Infectious Diseases Service, Royal Melbourne Hospital, Parkville 3050, Australia, and
| | - T. Bernard Kinane
- From the Program of Developmental Immunology, Department of Pediatrics, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114
| | - Kazue Takahashi
- From the Program of Developmental Immunology, Department of Pediatrics, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114
| | - Gregory L. Stahl
- Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115
| | - Gene G. Olinger
- Virology Division, United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, Frederick, Maryland 21702
| | - Gregory T. Spear
- Department of Immunology/Microbiology, Rush University Medical Center, Chicago, Illinois 60612
| | - R. Alan B. Ezekowitz
- From the Program of Developmental Immunology, Department of Pediatrics, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114
| | - Emmett V. Schmidt
- From the Program of Developmental Immunology, Department of Pediatrics, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114
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28
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Pedersen MB, Zhou X, Larsen EKU, Sørensen US, Kjems J, Nygaard JV, Nyengaard JR, Meyer RL, Boesen T, Vorup-Jensen T. Curvature of synthetic and natural surfaces is an important target feature in classical pathway complement activation. THE JOURNAL OF IMMUNOLOGY 2010; 184:1931-45. [PMID: 20053940 DOI: 10.4049/jimmunol.0902214] [Citation(s) in RCA: 78] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The binding of Abs to microbial surfaces followed by complement activation constitutes an important line of defense against infections. In this study, we have investigated the relationship between complement activation and the binding of human IgM Abs to surfaces with different curvatures. IgM Abs to dextran were shown to activate complement potently on dextran-coated particles having a diameter around 250 nm, whereas larger (600 nm) particles were less potent activators. This selectivity regarding particle dimension was also found for complement activation by colloidal substances of microbial origin. Peptidoglycan (PGN) is the major chemical component in the cell wall of Gram-positive bacteria. Fragments of purified PGN with sizes of approximately 100 nm promoted complement activation effectively through the classical pathway. By contrast, larger or smaller fragments of PGN did not activate complement strongly. A careful analysis of PGN fragments released during planctonic growth of Staphylococcus aureus showed that these include curvatures that would permit strong IgM-mediated complement activation, whereas the curvature of intact cells would be less effective for such activation. Consistently, we found that the suspended PGN fragments were strong activators of complement through the classical pathway. We suggest that these fragments act as decoy targets for complement activation, providing protection for S. aureus against the host immune response to infection.
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29
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Kartashov AV, Serafini G, Dong M, Shipovskov S, Gazaryan I, Besenbacher F, Ferapontova EE. Long-range electron transfer in recombinant peroxidases anisotropically orientated on gold electrodes. Phys Chem Chem Phys 2010; 12:10098-107. [DOI: 10.1039/c0cp00605j] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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30
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Tanio M, Wakamatsu K, Kohno T. Binding site of C-reactive protein on M-ficolin. Mol Immunol 2009; 47:215-21. [PMID: 19853918 DOI: 10.1016/j.molimm.2009.09.032] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2009] [Revised: 09/04/2009] [Accepted: 09/25/2009] [Indexed: 01/03/2023]
Abstract
The binding abilities of human C-reactive protein (CRP) with the C-terminal fibrinogen-like (FBG) domain and the full-length form of human M-ficolin were investigated by pull-down and zonal affinity chromatography analyses. Pull-down assays using an N-acetyl-D-glucosamine (GlcNAc)-agarose column demonstrated that CRP binds to the trimeric FBG domains, and that the GlcNAc-binding ability of the FBG domain is unaffected by CRP binding. Interestingly, the full-length M-ficolin, comprising the N-terminal collagen-like (COL) and C-terminal FBG domains, displayed lower affinity for CRP, and the monomeric FBG domain showed virtually no binding to CRP, as qualitatively judged by zonal affinity chromatography using a GlcNAc column. These results indicated that CRP binding requires the trimeric form of the FBG domain, and that the presence of the COL domain reduces the interaction between CRP and M-ficolin. In addition, pull-down assays using a histidine-tag affinity column demonstrated that neither the full-length M-ficolin nor the trimeric FBG domains, immobilized through their C-terminal histidine tags, showed any affinity for CRP, indicating that the CRP binding site is located near Ala326 at the C-terminus of M-ficolin, spatially close to a neck region (around Pro115) between the FBG and COL domains. From these findings, we concluded that CRP binding is enhanced by conformational bending at the neck region of M-ficolin, to avoid steric hindrance by the COL domain. Such a situation may be generated by oligomeric M-ficolin binding to surfaces with widely distributed ligands, such as pathogens.
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Affiliation(s)
- Michikazu Tanio
- Mitsubishi Kagaku Institute of Life Sciences (MITILS), 11 Minamiooya, Machida, Tokyo 194-8511, Japan
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Jensenius H, Klein DCG, van Hecke M, Oosterkamp TH, Schmidt T, Jensenius JC. Mannan-binding lectin: structure, oligomerization, and flexibility studied by atomic force microscopy. J Mol Biol 2009; 391:246-59. [PMID: 19501100 DOI: 10.1016/j.jmb.2009.05.083] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2009] [Revised: 05/27/2009] [Accepted: 05/29/2009] [Indexed: 10/20/2022]
Abstract
Mannan-binding lectin (MBL) is the archetypical pathogen recognition molecule of the innate immune defense. Upon binding to microorganisms, reactions leading to the destruction of the offender ensue. MBL is an oligomer of structural subunits each composed of three identical polypeptides. We used atomic force microscopy to reveal tertiary and quaternary structures of MBL. The images in both air and buffer show a quaternary structure best described as "sertiform", that is, a hub from which the subunits fan out. The dimensions conform to those calculated from primary and secondary structures. The subunits associate with a preferred angle of 40 degrees between them. This angle is stable with respect to the degree of oligomerization for MBL of four subunits or more. Due to an interruption in the collagenous sequence, the arms of the subunits are expected to form a kink. We find that approximately 30% of the subunits are kinked and the kink angle distributed, quite broadly, around 145 degrees . The conformation and flexibility of the MBL molecule that we observe differ distinctly from the popular view of a "bouquet-like" configuration as that found for related members of the complement system such as C1q. This structural information will further the understanding of the specific functioning of the MBL pathway of complement activation.
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Affiliation(s)
- Henriette Jensenius
- Leiden Institute of Physics, Leiden University, Niels Bohrweg 2, Leiden, The Netherlands
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Discovering New Features of Protein Complexes Structures by Small-Angle X-Ray Scattering. APPLICATIONS OF SYNCHROTRON LIGHT TO SCATTERING AND DIFFRACTION IN MATERIALS AND LIFE SCIENCES 2009. [DOI: 10.1007/978-3-540-95968-7_11] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Dong M, Hovgaard MB, Mamdouh W, Xu S, Otzen DE, Besenbacher F. AFM-based force spectroscopy measurements of mature amyloid fibrils of the peptide glucagon. NANOTECHNOLOGY 2008; 19:384013. [PMID: 21832572 DOI: 10.1088/0957-4484/19/38/384013] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We report on the mechanical characterization of individual mature amyloid fibrils by atomic force microscopy (AFM) and AFM-based single-molecule force spectroscopy (SMFS). These self-assembling materials, formed from the 29-residue amphiphatic peptide hormone glucagon, were found to display a reversible elastic behaviour. Based on AFM morphology and SMFS studies, we suggest that the observed elasticity is due to a force-induced conformational transition which is reversible due to the β-helical conformation of protofibrils, allowing a high degree of extension. The elastic properties of such mature fibrils contribute to their high stability, suggesting that the internal hydrophobic interactions of amyloid fibrils are likely to be of fundamental importance in the assembly of amyloid fibrils and therefore for the understanding of the progression of their associated pathogenic disorders. In addition, such biological amyloid fibril structures with highly stable mechanical properties can potentially be used to produce nanofibres (nanowires) that may be suitable for nanotechnological applications.
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Affiliation(s)
- Mingdong Dong
- Interdisciplinary Nanoscience Center (iNANO), University of Aarhus, DK-8000 Aarhus C, Denmark. Department of Physics and Astronomy, University of Aarhus, DK-8000 Aarhus C, Denmark
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34
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Structural polymorphism of oligomeric adiponectin visualized by electron microscopy. J Mol Biol 2008; 381:419-30. [PMID: 18614177 DOI: 10.1016/j.jmb.2008.06.015] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2008] [Revised: 06/02/2008] [Accepted: 06/05/2008] [Indexed: 12/11/2022]
Abstract
Adiponectin, a macromolecular complex similar to the members of the C1q and other collagenous homologues, elicits diverse biological functions, including anti-diabetes, anti-atherosclerosis, anti-inflammation and anti-tumor activities, which have been directly linked to the high molecular weight (HMW) oligomeric structures formed by multiples of adiponectin trimers. Here, we report the 3-D reconstructions of isolated full-length, recombinant murine C39A adiponectin trimer and hexamer of wild-type trimers (the major HMW form) determined by single-particle analysis of electron micrographs. The pleiomorphic ensemble of collagen-like stretches of the trimers leads to a dynamic structure of HMW that partition into two major classes, the fan-shaped (class I) and bouquet-shaped (class II). In both of these, while the N termini cluster into a compact ellipsoid-shaped (approximately 60 Ax45 Ax45 A) volume, the collagenous domains assume a variety of arrangements. The domains are splayed by up to approximately 90 degrees in class I, can form a close-packed, up to approximately 100x40 A cylindrical assembly in class II, which can house about half of the 66 putative collagen-like sequence and the rest, tethered to the trimeric globular domains at the C terminus, are highly dynamic. As a result, the globular domains elaborate a variety of arrangements, covering an area of up to approximately 4.9x10(5) A(2) and up to approximately 320 A apart, some of which were captured in reconstructions of class II. Our reconstructions suggest that the N-terminal structured domain, agreeing approximately with the expected volume for the octadecameric assembly of the terminal 27 amino acids, is crucial to the formation of the functionally active HMW. On the other hand, conformational flexibility of the trimers at the C terminus can allow the HMW to access and cluster disparate target ligands binding to the globular domains, which may be necessary to activate cellular signaling leading to the remarkable functional diversity of adiponectin.
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Stapulionis R, Pinto Oliveira CL, Gjelstrup MC, Pedersen JS, Hokland ME, Hoffmann SV, Poulsen K, Jacobsen C, Vorup-Jensen T. Structural Insight into the Function of Myelin Basic Protein as a Ligand for Integrin αMβ2. THE JOURNAL OF IMMUNOLOGY 2008; 180:3946-56. [DOI: 10.4049/jimmunol.180.6.3946] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Pagh R, Duus K, Laursen I, Hansen PR, Mangor J, Thielens N, Arlaud GJ, Kongerslev L, Højrup P, Houen G. The chaperone and potential mannan-binding lectin (MBL) co-receptor calreticulin interacts with MBL through the binding site for MBL-associated serine proteases. FEBS J 2008; 275:515-26. [DOI: 10.1111/j.1742-4658.2007.06218.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Thormann E, Dreyer JK, Simonsen AC, Hansen PL, Hansen S, Holmskov U, Mouritsen OG. Dynamic strength of the interaction between lung surfactant protein D (SP-D) and saccharide ligands. Biochemistry 2007; 46:12231-7. [PMID: 17915943 DOI: 10.1021/bi700823k] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In order to investigate the dynamic strength of the interaction between lung surfactant protein D (SP-D) and different sugars, maltose, mannose, glucose, and galactose, we have used an atomic force microscope to monitor the interaction on a single molecule scale. The experiment is performed by measuring the rupture force when the SP-D-sugar bond is subjected to a continuously increasing force. Under these dynamic conditions, SP-D binds strongest to d-mannose and weakest to maltose and d-galactose. These results differ from equilibrium measurements wherein SP-D exhibits preference for maltose. On the basis of this finding, we propose that the binding of the disaccharide maltose to SP-D, which is energetically stronger than the binding of any of the monosacchrides, alters the structure of the binding site in a way that lowers the dynamic strength of the bond. We conclude that determining the strength of a protein-ligand bond under dynamic stress using an atomic force microscope is possibly more relevant for mimicking the actual nonequilibrium physiological situation in the lungs.
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Affiliation(s)
- Esben Thormann
- MEMPHYS, Department of Physics and Chemistry, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark.
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Hovgaard MB, Dong M, Otzen DE, Besenbacher F. Quartz crystal microbalance studies of multilayer glucagon fibrillation at the solid-liquid interface. Biophys J 2007; 93:2162-9. [PMID: 17513349 PMCID: PMC1959527 DOI: 10.1529/biophysj.107.109686] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2007] [Accepted: 05/10/2007] [Indexed: 02/08/2023] Open
Abstract
We have used a quartz crystal microbalance with dissipation (QCM-D) to monitor the changes in layer thickness and viscoelastic properties accompanying multilayer amyloid deposition in situ for the first time. By means of atomic force microscope imaging, an unequivocal correlation is established between the interfacial nucleation and growth of glucagon fibrils and the QCM-D response. The combination of the two techniques allows us to study the temporal evolution of the interfacial fibrillation process. We have modeled the QCM-D data using an extension to the Kelvin-Voigt viscoelastic model. Three phases were observed in the fibrillation process: 1), a rigid multilayer of glucagon monomers forms and slowly rearranges; 2), this multilayer subsequently evolves into a dramatically more viscoelastic layer, containing a polymorphic network of micrometer-long fibrils growing from multiple nucleation sites; and 3), the fibrillar formation effectively stops as a result of the depletion of bulk-phase monomers, although the process can be continued without a lag phase by subsequent addition of fresh monomers. The robustness of the QCM-D technique, consolidated by complementary atomic force microscope studies, should make it possible to combine different components thought to be involved in the plaque formation process and thus build up realistic models of amyloid plaque formation in vitro.
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Affiliation(s)
- Mads Bruun Hovgaard
- Interdisciplinary Nanoscience Center and Department of Physics and Astronomy, University of Aarhus, DK-8000 Aarhus C, Denmark
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Thiel S. Complement activating soluble pattern recognition molecules with collagen-like regions, mannan-binding lectin, ficolins and associated proteins. Mol Immunol 2007; 44:3875-88. [PMID: 17768106 DOI: 10.1016/j.molimm.2007.06.005] [Citation(s) in RCA: 182] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2007] [Indexed: 01/31/2023]
Abstract
Mannan-binding lectin (MBL), L-ficolin, M-ficolin and H-ficolin are all complement activating soluble pattern recognition molecules with recognition domains linked to collagen-like regions. All four may form complexes with four structurally related proteins, the three MBL-associated serine proteases (MASPs), MASP-1, MASP-2 and MASP-3, and a smaller MBL-associated protein (MAp19). The four recognition molecules recognize patterns of carbohydrate or acetyl-group containing ligands. After binding to the relevant targets all four are able to activate the complement system. We thus have a system where four different and/or overlapping patterns of microbial origin or patterns of altered-self may be recognized, but in all cases the signalling molecules, the MASPs, are shared. MASP-1 and MASP-3 are formed from one gene, MASP1/3, by alternative splicing generating two different mRNAs from a single primary transcript. Similarly MASP-2 and MAp19 are both generated from one gene, MASP-2/MAp19, by alternative splicing. A number of non-synonymous polymorphisms of the four recognition molecules and of the MASPs are known, and the implications of these alterations are being studied. The clinical impact of deficiencies will be discussed.
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Affiliation(s)
- Steffen Thiel
- Department of Medical Microbiology and Immunology, University of Aarhus, Wilhelms Meyers Allé, 8000 Aarhus C, Denmark.
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Panepinto JC, Komperda KW, Hacham M, Shin S, Liu X, Williamson PR. Binding of serum mannan binding lectin to a cell integrity-defective Cryptococcus neoformans ccr4Delta mutant. Infect Immun 2007; 75:4769-79. [PMID: 17646356 PMCID: PMC2044520 DOI: 10.1128/iai.00536-07] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Mannan binding lectin (MBL) is an innate immune mediator belonging to the collectin family known to bind to the surfaces of many viruses, bacteria, and fungi. However, pathogenic strains of the fungus Cryptococcus neoformans are resistant to MBL binding. To dissect the mechanism of cryptococcal resistance to MBL, we compared MBL binding to an encapsulated wild-type strain, an encapsulated ccr4Delta mutant defective in cell integrity, and an acapsular cap60Delta strain. No MBL binding was detected on wild-type C. neoformans. In contrast, the ccr4Delta mutant bound MBL to the cell wall, predominantly at the ends of enlarged buds, whereas the acapsular strain bound MBL only at the bud neck and bud scars. In addition, the ccr4Delta mutant was sensitive to the cell wall-active antifungal caspofungin and other cell wall stress inducers, and its virulence was reduced in a mouse model of cryptococcosis. Interestingly, treatment of wild-type cells with caspofungin also increased MBL binding to C. neoformans. These results suggest that both the presence of capsule and wild-type cell wall architecture preclude MBL binding to C. neoformans.
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Affiliation(s)
- John C Panepinto
- University of Illinois at Chicago, Section of Infectious Diseases, Chicago, IL 60612, USA.
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