1
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Ma Z, Song B, Yu L, Yang J, Han Z, Yang J, Wang B, Song D, Xu H, Qiao M. Efficient expression of hydrophobin HGFII-his via POT1-mediated δ integration strategy and its potential in curcumin nanoformulation. Colloids Surf A Physicochem Eng Asp 2023. [DOI: 10.1016/j.colsurfa.2022.130344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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2
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Romero-Arias JR, Luviano AS, Costas M, Hernandez-Machado A, Barrio RA. Dynamical shapes of droplets of cyclodextrin-surfactant solutions. Sci Rep 2022; 12:5252. [PMID: 35347194 PMCID: PMC8960811 DOI: 10.1038/s41598-022-09267-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Accepted: 02/04/2022] [Indexed: 11/26/2022] Open
Abstract
We present a series of experiments with droplets of aqueous cyclodextrin-surfactant solutions, in which the volume is reduced after the equilibrium spherical shape is reached. The final shape of the drop after this perturbation is found to be dependent on the concentration of inclusion complexes in the bulk of the solution. These inclusion complexes are formed by two cyclodextrin molecules and one surfactat molecule. We propose a model to describe these dynamical processes. Dipole–dipole interactions on the surface of the drop trigger a competition between water surface tension and dipole–dipole interaction energies. The results of the model reproduce the spherical and rod-like shapes found in the experiments.
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Affiliation(s)
- J Roberto Romero-Arias
- Instituto de Investigaciones en Matemáticas Aplicadas y en Sistemas, Universidad Nacional Autónoma de México, 01000, Mexico City, Mexico
| | - Alberto S Luviano
- Laboratorio de Bio-fisicoquímica, Departamento de Fisicoquímica, Facultad de Química, Universidad Nacional Autónoma de México, 04510, Mexico City, Mexico
| | - Miguel Costas
- Laboratorio de Bio-fisicoquímica, Departamento de Fisicoquímica, Facultad de Química, Universidad Nacional Autónoma de México, 04510, Mexico City, Mexico
| | - Aurora Hernandez-Machado
- Department of Condensed Matter Physics, University of Barcelona (UB), Barcelona, Spain.,Institute of Nanoscience and Nanotechnology (IN2UB), University of Barcelona (UB), Barcelona, Spain
| | - Rafael A Barrio
- Instituto de Física, Universidad Nacional Autónoma de México, 01000, Mexico City, Mexico.
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3
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Mokhtari-Abpangoui M, Lohrasbi-Nejad A, Zolala J, Torkzadeh-Mahani M, Ghanbari S. Improvement Thermal Stability of D-Lactate Dehydrogenase by Hydrophobin-1 and in Silico Prediction of Protein-Protein Interactions. Mol Biotechnol 2021; 63:919-932. [PMID: 34109551 DOI: 10.1007/s12033-021-00342-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Accepted: 05/18/2021] [Indexed: 10/21/2022]
Abstract
Hydrophobins are small surface-active proteins. They can connect to hydrophobic or hydrophilic regions and oligomerize in solution to form massive construction. In nature, these proteins are produced by filamentous fungi at different stages of growth. So far, researchers have used them in various fields of biotechnology. In this study, recombinant hydrophobin-1 (rHFB1, 7.5 kDa) was used to stabilize recombinant D-lactate dehydrogenase (rD-LDH, 35 kDa). rD-LDH is a sensitive enzyme deactivated and oxidized by external agents such as O2 and lights. So, its stabilization with rHFB1 can be the best index to demonstrate the positive effect of rHFB1 on preserving and improving enzyme's activity. The unique ability of rHFB1 for interacting with hydrophobic regions of rD-LDH was predicted by protein-protein docking study with ClusPro and PIC servers and confirmed by fluorescence experiments, and Colorless Native-PAGE. Measurement of thermodynamic parameters allows for authenticating the role of rHFB1 as a thermal stabilizer in the protein-protein complex (rD-LDH@rHFB1). Interaction between rHFB1 and rD-LDH improved half-life of enzyme 2.25-fold at 40 °C. Investigation of the kinetic parameters proved that the presence of rHFB1 along with the rD-LDH enhancement strongly the affinity of the enzyme for pyruvate. Furthermore, an increase of Kcat/Km for complex displayed the effect of rHFB1 for improving the enzyme's catalytic efficiency.
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Affiliation(s)
| | - Azadeh Lohrasbi-Nejad
- Department of Agricultural Biotechnology, Shahid Bahonar University of Kerman, Kerman, Iran.
| | - Jafar Zolala
- Department of Agricultural Biotechnology, Shahid Bahonar University of Kerman, Kerman, Iran
| | - Masoud Torkzadeh-Mahani
- Department of Biotechnology, Institute of Science and High Technology and Environmental Sciences, Graduate University of Advanced Technology, Kerman, Iran
| | - Saba Ghanbari
- Department of Biotechnology, Institute of Science and High Technology and Environmental Sciences, Graduate University of Advanced Technology, Kerman, Iran
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4
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Paananen A, Weich S, Szilvay GR, Leitner M, Tappura K, Ebner A. Quantifying biomolecular hydrophobicity: Single molecule force spectroscopy of class II hydrophobins. J Biol Chem 2021; 296:100728. [PMID: 33933454 PMCID: PMC8164047 DOI: 10.1016/j.jbc.2021.100728] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Revised: 04/25/2021] [Accepted: 04/28/2021] [Indexed: 11/30/2022] Open
Abstract
Hydrophobins are surface-active proteins produced by filamentous fungi. The amphiphilic structure of hydrophobins is very compact, containing a distinct hydrophobic patch on one side of the molecule, locked by four intramolecular disulfide bridges. Hydrophobins form dimers and multimers in solution to shield these hydrophobic patches from water exposure. Multimer formation in solution is dynamic, and hydrophobin monomers can be exchanged between multimers. Unlike class I hydrophobins, class II hydrophobins assemble into highly ordered films at the air-water interface. In order to increase our understanding of the strength and nature of the interaction between hydrophobins, we used atomic force microscopy for single molecule force spectroscopy to explore the molecular interaction forces between class II hydrophobins from Trichoderma reesei under different environmental conditions. A genetically engineered hydrophobin variant, NCys-HFBI, enabled covalent attachment of proteins to the apex of the atomic force microscopy cantilever tip and sample surfaces in controlled orientation with sufficient freedom of movement to measure molecular forces between hydrophobic patches. The measured rupture force between two assembled hydrophobins was ∼31 pN, at a loading rate of 500 pN/s. The results indicated stronger interaction between hydrophobins and hydrophobic surfaces than between two assembling hydrophobin molecules. Furthermore, this interaction was stable under different environmental conditions, which demonstrates the dominance of hydrophobicity in hydrophobin-hydrophobin interactions. This is the first time that interaction forces between hydrophobin molecules, and also between naturally occurring hydrophobic surfaces, have been measured directly at a single-molecule level.
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Affiliation(s)
- Arja Paananen
- Industrial Biotechnology and Food, VTT Technical Research Centre of Finland Ltd, Espoo, Finland.
| | - Sabine Weich
- Department of Applied Experimental Biophysics, Institute of Biophysics, Johannes Kepler University Linz, Linz, Austria
| | - Géza R Szilvay
- Industrial Biotechnology and Food, VTT Technical Research Centre of Finland Ltd, Espoo, Finland
| | - Michael Leitner
- Department of Applied Experimental Biophysics, Institute of Biophysics, Johannes Kepler University Linz, Linz, Austria
| | - Kirsi Tappura
- Industrial Biotechnology and Food, VTT Technical Research Centre of Finland Ltd, Espoo, Finland
| | - Andreas Ebner
- Department of Applied Experimental Biophysics, Institute of Biophysics, Johannes Kepler University Linz, Linz, Austria.
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5
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Romero-Arias JR, S Luviano A, Costas M, Hernández-Machado A, Barrio RA. Dipole-dipole interactions control the interfacial rheological response of cyclodextrin/surfactant solutions. SOFT MATTER 2021; 17:2652-2658. [PMID: 33533369 DOI: 10.1039/d0sm01796e] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
A recent surface rheological study has shown that aqueous solutions of α-cyclodextrin (αCD) with anionic surfactants (S) display a remarkable viscoelasticity at the liquid/air interface, which has not been observed in similar systems. The dilatational modulus is various orders of magnitude larger than those for the binary mixtures αCD + water and S + water. The rheological response has been qualitatively related to the bulk distribution of species, the 2 : 1 inclusion complexes (αCD2 : S) playing a fundamental role. In this work, we have developed a model that considers dipole-dipole interactions between 2 : 1 inclusion complexes ordered on the liquid/air interface. When the model is applied to the specific experimental conditions, the dependencies on concentration and temperature of the dilatational modulus and the surface tension were found to be in excellent agreement with the data, indicating clearly that dipole-dipole interactions determine and control the rheological behavior of the interface.
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Affiliation(s)
- J Roberto Romero-Arias
- Instituto de Investigaciones en Matemáticas Aplicadas y en Sistemas, Universidad Nacional Autónoma de México, CdMx 01000, Mexico
| | - Alberto S Luviano
- Laboratorio de Biofisicoquímica, Departamento de Fisicoquímica, Facultad de Química, Universidad Nacional Autónoma de México, CdMx 04510, Mexico
| | - Miguel Costas
- Laboratorio de Biofisicoquímica, Departamento de Fisicoquímica, Facultad de Química, Universidad Nacional Autónoma de México, CdMx 04510, Mexico
| | - Aurora Hernández-Machado
- Department of Condensed Matter Physics, University of Barcelona (UB), Barcelona, Spain and Institute of Nanoscience and Nanotechnology (IN2UB)
| | - Rafael A Barrio
- Instituto de Física, Universidad Nacional Autónoma de México, 01000 CdMx, Mexico.
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6
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Chang HJ, Choi H, Na S. Predicting the self-assembly film structure of class II hydrophobin NC2 and estimating its structural characteristics. Colloids Surf B Biointerfaces 2020; 195:111269. [DOI: 10.1016/j.colsurfb.2020.111269] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Revised: 07/15/2020] [Accepted: 07/21/2020] [Indexed: 11/24/2022]
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7
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Analysis of a putative glycosylation site in the Trichoderma virens elicitor SM1 reveals no role in protein dimerization. Biochem Biophys Res Commun 2019; 509:817-821. [DOI: 10.1016/j.bbrc.2019.01.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2018] [Accepted: 01/03/2019] [Indexed: 11/18/2022]
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8
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Ujor VC, Adukwu EC, Okonkwo CC. Fungal wars: The underlying molecular repertoires of combating mycelia. Fungal Biol 2018; 122:191-202. [PMID: 29551193 DOI: 10.1016/j.funbio.2018.01.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Revised: 01/05/2018] [Accepted: 01/06/2018] [Indexed: 10/18/2022]
Abstract
Non-self contact between fungi elicits strong morphological and biochemical reactions in the mycelia of interacting species. Although these reactions appear to be species- and interaction-specific, some responses such as pigmentation, increased secretion of phenol-oxidases, barrage formation and sealing of the mycelia front are common responses in most interactions. Hence, some species recruit similar molecular machineries in response to non-self. Increasing number of fully sequenced and annotated fungal genomes and advances in genome-wide and global proteome analytical tools now allow researchers to use techniques such as RNA sequencing, micro and macroarray analysis, 2-dimensional protein gel profiling, and differential display of mRNA to probe the underlying molecular mechanisms of combative mycelial interactions. This review provides an overview of the genes and proteins found to be differentially expressed in conflicting fungal mycelia by the use of 'omics' tools. Connections between observed gene and protein repertoires of competing mycelia and the attendant morphological and biochemical changes are presented.
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Affiliation(s)
- Victor C Ujor
- Bioenergy and Biological Waste Management Program, Agricultural Technical Institute, The Ohio State University, 1328 Dover Road, Wooster, OH, USA.
| | - Emmanuel C Adukwu
- Department of Applied Sciences, University of the West of England, Frenchay Campus, Cold Harbour Lane, Bristol, BS16 1QY, United Kingdom
| | - Christopher C Okonkwo
- Department of Animal Sciences, The Ohio State University, Ohio Agricultural Research and Development Center, 1680 Madison Avenue, Wooster, OH, 44691, USA
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9
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Natural variations in the biofilm-associated protein BslA from the genus Bacillus. Sci Rep 2017; 7:6730. [PMID: 28751732 PMCID: PMC5532214 DOI: 10.1038/s41598-017-06786-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2016] [Accepted: 06/19/2017] [Indexed: 01/25/2023] Open
Abstract
BslA is a protein secreted by Bacillus subtilis which forms a hydrophobic film that coats the biofilm surface and renders it water-repellent. We have characterised three orthologues of BslA from Bacillus amyloliquefaciens, Bacillus licheniformis and Bacillus pumilus as well as a paralogue from B. subtilis called YweA. We find that the three orthologous proteins can substitute for BslA in B. subtilis and confer a degree of protection, whereas YweA cannot. The degree to which the proteins functionally substitute for native BslA correlates with their in vitro biophysical properties. Our results demonstrate the use of naturally-evolved variants to provide a framework for teasing out the molecular basis of interfacial self-assembly.
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10
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Production and characterization of stable foams with fine bubbles from solutions of hydrophobin HFBII and its mixtures with other proteins. Colloids Surf A Physicochem Eng Asp 2017. [DOI: 10.1016/j.colsurfa.2016.06.018] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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11
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Riccardi L, Mereghetti P. Induced Fit in Protein Multimerization: The HFBI Case. PLoS Comput Biol 2016; 12:e1005202. [PMID: 27832079 PMCID: PMC5104427 DOI: 10.1371/journal.pcbi.1005202] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Accepted: 10/12/2016] [Indexed: 01/21/2023] Open
Abstract
Hydrophobins, produced by filamentous fungi, are small amphipathic proteins whose biological functions rely on their unique surface-activity properties. Understanding the mechanistic details of the multimerization process is of primary importance to clarify the interfacial activity of hydrophobins. We used free energy calculations to study the role of a flexible β-hairpin in the multimerization process in hydrophobin II from Trichoderma reesei (HFBI). We characterized how the displacement of this β-hairpin controls the stability of the monomers/dimers/tetramers in solution. The regulation of the oligomerization equilibrium of HFBI will necessarily affect its interfacial properties, fundamental for its biological function and for technological applications. Moreover, we propose possible routes for the multimerization process of HFBI in solution. This is the first case where a mechanism by which a flexible loop flanking a rigid patch controls the protein-protein binding equilibrium, already known for proteins with charged binding hot-spots, is described within a hydrophobic patch. Fungi proliferate by creating a complex hyphal network growing within a wet environment. However, for most fungi to colonize new territories, they must produce spores carried by aerial hyphae and spread them into the air. Aerial structures need to overcome the surface tension of the surrounding water in order to grow into the air. This process requires hydrophobins, a remarkable class of self-associating fungal proteins which lower the surface tension at the air/water interface by creating a thin amphipathic layer. In solution they form multimers in equilibrium with the interfacial layer. Due to their unique surface-activity properties, hydrophobins have been used for a variety of biotechnical applications. We used enhanced sampling molecular dynamics simulations methods to study the multimerization process in solution of a hydrophobin from Trichoderma reesei (HFBI). We clarified the fundamental role of a small flexible region within the HFBI monomer involved in the formation of multimers. A flexible loop flanking a rigid interaction patch is able to fine-tune the interaction energy. This mechanism, already known for charged binding patches, is described here for hydrophobic hot-spots. This result is remarkably important in order to clarify the mechanism of arranging at the interface and enhancing hydrophobin-based technological applications.
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Affiliation(s)
- Laura Riccardi
- Laboratory of Molecular Modeling and Drug Discovery, Istituto Italiano di Tecnologia, Genoa, Italy
| | - Paolo Mereghetti
- Center for Nanotechnology Innovation @NEST, Istituto Italiano di Tecnologia, Pisa, Italy
- * E-mail:
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12
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Limited coalescence and Ostwald ripening in emulsions stabilized by hydrophobin HFBII and milk proteins. Colloids Surf A Physicochem Eng Asp 2016. [DOI: 10.1016/j.colsurfa.2016.09.066] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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13
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Gazzera L, Milani R, Pirrie L, Schmutz M, Blanck C, Resnati G, Metrangolo P, Krafft MP. Design of Highly Stable Echogenic Microbubbles through Controlled Assembly of Their Hydrophobin Shell. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201603706] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Lara Gazzera
- NFMLab; Politecnico di Milano; Via Mancinelli 7 20131 Milano Italy
| | - Roberto Milani
- VTT-Technical Research Centre of Finland Ltd; Biologinkuja 7 Espoo 02044 VTT Finland
| | - Lisa Pirrie
- VTT-Technical Research Centre of Finland Ltd; Biologinkuja 7 Espoo 02044 VTT Finland
| | - Marc Schmutz
- Institut Charles Sadron (CNRS); University of Strasbourg; 23 rue du Loess 67034 Strasbourg France
| | - Christian Blanck
- Institut Charles Sadron (CNRS); University of Strasbourg; 23 rue du Loess 67034 Strasbourg France
| | - Giuseppe Resnati
- NFMLab; Politecnico di Milano; Via Mancinelli 7 20131 Milano Italy
| | - Pierangelo Metrangolo
- NFMLab; Politecnico di Milano; Via Mancinelli 7 20131 Milano Italy
- VTT-Technical Research Centre of Finland Ltd; Biologinkuja 7 Espoo 02044 VTT Finland
| | - Marie Pierre Krafft
- Institut Charles Sadron (CNRS); University of Strasbourg; 23 rue du Loess 67034 Strasbourg France
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14
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Gazzera L, Milani R, Pirrie L, Schmutz M, Blanck C, Resnati G, Metrangolo P, Krafft MP. Design of Highly Stable Echogenic Microbubbles through Controlled Assembly of Their Hydrophobin Shell. Angew Chem Int Ed Engl 2016; 55:10263-7. [DOI: 10.1002/anie.201603706] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2016] [Revised: 05/19/2016] [Indexed: 11/08/2022]
Affiliation(s)
- Lara Gazzera
- NFMLab; Politecnico di Milano; Via Mancinelli 7 20131 Milano Italy
| | - Roberto Milani
- VTT-Technical Research Centre of Finland Ltd; Biologinkuja 7 Espoo 02044 VTT Finland
| | - Lisa Pirrie
- VTT-Technical Research Centre of Finland Ltd; Biologinkuja 7 Espoo 02044 VTT Finland
| | - Marc Schmutz
- Institut Charles Sadron (CNRS); University of Strasbourg; 23 rue du Loess 67034 Strasbourg France
| | - Christian Blanck
- Institut Charles Sadron (CNRS); University of Strasbourg; 23 rue du Loess 67034 Strasbourg France
| | - Giuseppe Resnati
- NFMLab; Politecnico di Milano; Via Mancinelli 7 20131 Milano Italy
| | - Pierangelo Metrangolo
- NFMLab; Politecnico di Milano; Via Mancinelli 7 20131 Milano Italy
- VTT-Technical Research Centre of Finland Ltd; Biologinkuja 7 Espoo 02044 VTT Finland
| | - Marie Pierre Krafft
- Institut Charles Sadron (CNRS); University of Strasbourg; 23 rue du Loess 67034 Strasbourg France
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15
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Schor M, Reid JL, MacPhee CE, Stanley-Wall NR. The Diverse Structures and Functions of Surfactant Proteins. Trends Biochem Sci 2016; 41:610-620. [PMID: 27242193 PMCID: PMC4929970 DOI: 10.1016/j.tibs.2016.04.009] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Revised: 04/25/2016] [Accepted: 04/29/2016] [Indexed: 01/26/2023]
Abstract
Surface tension at liquid–air interfaces is a major barrier that needs to be surmounted by a wide range of organisms; surfactant and interfacially active proteins have evolved for this purpose. Although these proteins are essential for a variety of biological processes, our understanding of how they elicit their function has been limited. However, with the recent determination of high-resolution 3D structures of several examples, we have gained insight into the distinct shapes and mechanisms that have evolved to confer interfacial activity. It is now a matter of harnessing this information, and these systems, for biotechnological purposes. Interfacially active proteins fulfill a wide range of biological functions in organisms ranging from bacteria and fungi to mammals. Their physicochemical properties make interfacially active proteins attractive for biotechnological applications; for example, as coatings on nanodevices or medical implants and as emulsifiers in food and personal-care products. High-resolution 3D structures show that the mechanisms by which interfacially active proteins achieve their function are highly diverse.
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Affiliation(s)
- Marieke Schor
- School of Physics and Astronomy, University of Edinburgh, Edinburgh, UK
| | - Jack L Reid
- School of Life Sciences, University of Dundee, Dundee, UK
| | - Cait E MacPhee
- School of Physics and Astronomy, University of Edinburgh, Edinburgh, UK.
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16
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Bromley KM, Morris RJ, Hobley L, Brandani G, Gillespie RMC, McCluskey M, Zachariae U, Marenduzzo D, Stanley-Wall NR, MacPhee CE. Interfacial self-assembly of a bacterial hydrophobin. Proc Natl Acad Sci U S A 2015; 112:5419-24. [PMID: 25870300 PMCID: PMC4418867 DOI: 10.1073/pnas.1419016112] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The majority of bacteria in the natural environment live within the confines of a biofilm. The Gram-positive bacterium Bacillus subtilis forms biofilms that exhibit a characteristic wrinkled morphology and a highly hydrophobic surface. A critical component in generating these properties is the protein BslA, which forms a coat across the surface of the sessile community. We recently reported the structure of BslA, and noted the presence of a large surface-exposed hydrophobic patch. Such surface patches are also observed in the class of surface-active proteins known as hydrophobins, and are thought to mediate their interfacial activity. However, although functionally related to the hydrophobins, BslA shares no sequence nor structural similarity, and here we show that the mechanism of action is also distinct. Specifically, our results suggest that the amino acids making up the large, surface-exposed hydrophobic cap in the crystal structure are shielded in aqueous solution by adopting a random coil conformation, enabling the protein to be soluble and monomeric. At an interface, these cap residues refold, inserting the hydrophobic side chains into the air or oil phase and forming a three-stranded β-sheet. This form then self-assembles into a well-ordered 2D rectangular lattice that stabilizes the interface. By replacing a hydrophobic leucine in the center of the cap with a positively charged lysine, we changed the energetics of adsorption and disrupted the formation of the 2D lattice. This limited structural metamorphosis represents a previously unidentified environmentally responsive mechanism for interfacial stabilization by proteins.
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Affiliation(s)
- Keith M Bromley
- School of Physics and Astronomy, University of Edinburgh, Edinburgh EH9 3FD, United Kingdom
| | - Ryan J Morris
- School of Physics and Astronomy, University of Edinburgh, Edinburgh EH9 3FD, United Kingdom
| | - Laura Hobley
- Division of Molecular Microbiology, College of Life Sciences, University of Dundee, Dundee DD1 5EH, United Kingdom; and
| | - Giovanni Brandani
- School of Physics and Astronomy, University of Edinburgh, Edinburgh EH9 3FD, United Kingdom
| | - Rachel M C Gillespie
- Division of Molecular Microbiology, College of Life Sciences, University of Dundee, Dundee DD1 5EH, United Kingdom; and
| | - Matthew McCluskey
- School of Physics and Astronomy, University of Edinburgh, Edinburgh EH9 3FD, United Kingdom
| | - Ulrich Zachariae
- Division of Computational Biology, College of Life Sciences, University of Dundee, Dundee DD1 5EH, United Kingdom
| | - Davide Marenduzzo
- School of Physics and Astronomy, University of Edinburgh, Edinburgh EH9 3FD, United Kingdom
| | - Nicola R Stanley-Wall
- Division of Molecular Microbiology, College of Life Sciences, University of Dundee, Dundee DD1 5EH, United Kingdom; and
| | - Cait E MacPhee
- School of Physics and Astronomy, University of Edinburgh, Edinburgh EH9 3FD, United Kingdom;
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17
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Applications of hydrophobins: current state and perspectives. Appl Microbiol Biotechnol 2015; 99:1587-97. [PMID: 25564034 DOI: 10.1007/s00253-014-6319-x] [Citation(s) in RCA: 103] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Revised: 12/08/2014] [Accepted: 12/09/2014] [Indexed: 01/07/2023]
Abstract
Hydrophobins are proteins exclusively produced by filamentous fungi. They self-assemble at hydrophilic-hydrophobic interfaces into an amphipathic film. This protein film renders hydrophobic surfaces of gas bubbles, liquids, or solid materials wettable, while hydrophilic surfaces can be turned hydrophobic. These properties, among others, make hydrophobins of interest for medical and technical applications. For instance, hydrophobins can be used to disperse hydrophobic materials; to stabilize foam in food products; and to immobilize enzymes, peptides, antibodies, cells, and anorganic molecules on surfaces. At the same time, they may be used to prevent binding of molecules. Furthermore, hydrophobins have therapeutic value as immunomodulators and can been used to produce recombinant proteins.
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18
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Li W, Gong Y, Xu H, Qiao M, Niu B. Identification properties of a recombinant class I hydrophobin rHGFI. Int J Biol Macromol 2015; 72:658-63. [DOI: 10.1016/j.ijbiomac.2014.09.014] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2014] [Revised: 09/12/2014] [Accepted: 09/13/2014] [Indexed: 10/24/2022]
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19
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Euston SR. Molecular simulation of adsorption of hydrophobin HFBI to the air–water, DPPC–water and decane–water interfaces. Food Hydrocoll 2014. [DOI: 10.1016/j.foodhyd.2013.12.005] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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20
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Lee S, Røn T, Pakkanen KI, Linder M. Hydrophobins as aqueous lubricant additive for a soft sliding contact. Colloids Surf B Biointerfaces 2014; 125:264-9. [PMID: 25466456 DOI: 10.1016/j.colsurfb.2014.10.044] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2014] [Revised: 10/07/2014] [Accepted: 10/22/2014] [Indexed: 11/19/2022]
Abstract
Two type II fungal hydrophobins, HFBI and FpHYD5, have been studied as aqueous lubricant additive at a nonpolar, compliant sliding contact (self-mated poly(dimethylsiloxane) (PDMS) contact) at two different concentrations, 0.1 mg/mL and 1.0 mg/mL. The two hydrophobins are featured as non-glycosylated (HFBI, m.w. ca. 7 kDa) vs glycosylated (FpHYD5, m.w. ca. 10 kDa) proteins. Far UV CD spectra of the two hydrophobins were very similar, suggesting overall structural similarity, but showed a noticeable difference according to the concentration. This is proposed to be related to the formation of multimers at 1.0 mg/mL. Despite 10-fold difference in the bulk concentration, the adsorbed masses of the hydrophobins onto PDMS surface obtained from the two solutions (0.1 and 1.0 mg/mL) were nearly identical, suggesting that a monolayer of the hydrophobins are formed from 0.1 mg/mL solution. PDMS-PDMS sliding interface was effectively lubricated by the hydrophobin solutions, and showed a reduction in the coefficient of friction by as much as ca. two orders of magnitude. Higher concentration solution (1.0 mg/mL) provided a superior lubrication, particularly in low-speed regime, where boundary lubrication characteristic is dominant via 'self-healing' mechanism. FpHYD5 revealed a better lubrication than HFBI presumably due to the presence of glycans and improved hydration of the sliding interface. Two type II hydrophobins function more favorably compared to a synthetic amphiphilic copolymer, PEO-PPO-PEO, with a similar molecular weight. This is ascribed to higher amount of adsorption of the hydrophobins to hydrophobic surfaces from aqueous solution.
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Affiliation(s)
- Seunghwan Lee
- Department of Mechanical Engineering, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark.
| | - Troels Røn
- Department of Mechanical Engineering, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark
| | - Kirsi I Pakkanen
- Department of Mechanical Engineering, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark
| | - Markus Linder
- Technical Research Centre of Finland, VTT Biotechnology, FIN-02044 VTT, Finland; Department of Biotechnology and Chemical Technology, Aalto University, 00076 Aalto, Finland
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21
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Terhem RB, van Kan JAL. Functional analysis of hydrophobin genes in sexual development of Botrytis cinerea. Fungal Genet Biol 2014; 71:42-51. [PMID: 25181040 DOI: 10.1016/j.fgb.2014.08.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2014] [Revised: 08/03/2014] [Accepted: 08/04/2014] [Indexed: 10/24/2022]
Abstract
Hydrophobins are small secreted fungal proteins that play roles in growth and development of filamentous fungi, i.e. in the formation of aerial structures and the attachment of hyphae to hydrophobic surfaces. In Botrytis cinerea, three hydrophobin genes have been identified. Studies by Mosbach et al. (2011) showed that hydrophobins are neither involved in conferring surface hydrophobicity to conidia and aerial hyphae of B. cinerea, nor are they required for virulence. The present study investigated the role of hydrophobins in sclerotium and apothecium development. Expression analysis revealed high expression of the Bhp1 gene during different stages of apothecium development. Two Bhp1 splice variants were detected that differ by an internal stretch of 13 amino acid residues. Seven different mutants in which either a single, two or three hydrophobin genes were knocked out, as well as two wild type strains of opposite mating types, were characterized for sclerotium and apothecium development. No aberrant morphology was observed in sclerotium development when single deletion mutants in hydrophobin genes were analyzed. Sclerotia of double knock out mutant ΔBhp1/ΔBhp3 and the triple knock out mutant, however, showed easily wettable phenotypes. For analyzing apothecium development, a reciprocal crossing scheme was setup. Morphological aberrations were observed in crosses with two hydrophobin mutants. When the double knock out mutant ΔBhp1/ΔBhp2 and the triple knock out mutant were used as the maternal parent (sclerotia), and fertilized with wild type microconidia, the resulting apothecia were swollen, dark brown in color and had a blotched surface. After initially growing upwards toward the light source, the apothecia in many cases collapsed due to loss of structural integrity. Aberrant apothecium development was not observed in the reciprocal cross, when these same mutants were used as the paternal parent (microconidia). These results indicate that the presence of hydrophobins in maternal tissue is important for normal development of apothecia of B. cinerea.
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Affiliation(s)
- Razak B Terhem
- Department of Forest Management, Faculty of Forestry, Universiti Putra Malaysia, 43400 Serdang, Malaysia; Wageningen University, Laboratory of Phytopathology, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands
| | - Jan A L van Kan
- Wageningen University, Laboratory of Phytopathology, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands.
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22
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Ren Q, Kwan AH, Sunde M. Solution structure and interface-driven self-assembly of NC2, a new member of the Class II hydrophobin proteins. Proteins 2013; 82:990-1003. [PMID: 24218020 DOI: 10.1002/prot.24473] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2013] [Revised: 10/20/2013] [Accepted: 10/29/2013] [Indexed: 11/10/2022]
Abstract
Hydrophobins are fungal proteins that self-assemble spontaneously to form amphipathic monolayers at hydrophobic:hydrophilic interfaces. Hydrophobin assemblies facilitate fungal transitions between wet and dry environments and interactions with plant and animal hosts. NC2 is a previously uncharacterized hydrophobin from Neurospora crassa. It is a highly surface active protein and is able to form protein layers on a water:air interface that stabilize air bubbles. On a hydrophobic substrate, NC2 forms layers consisting of an ordered network of protein molecules, which dramatically decrease the water contact angle. The solution structure and dynamics of NC2 have been determined using nuclear magnetic resonance spectroscopy. The structure of this protein displays the same core fold as observed in other hydrophobin structures determined to date, including the Class II hydrophobins HFBI and HFBII from Trichoderma reesei, but certain features illuminate the structural differences between Classes I and II hydrophobins and also highlight the variations between structures of Class II hydrophobin family members. The unique properties of hydrophobins have attracted much attention for biotechnology applications. The insights obtained through determining the structure, biophysical properties and assembly characteristics of NC2 will facilitate the development of hydrophobin-based applications.
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Affiliation(s)
- Qin Ren
- Discipline of Pharmacology, School of Medical Sciences, University of Sydney, Sydney, New South Wales, 2006, Australia
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Green AJ, Littlejohn KA, Hooley P, Cox PW. Formation and stability of food foams and aerated emulsions: Hydrophobins as novel functional ingredients. Curr Opin Colloid Interface Sci 2013. [DOI: 10.1016/j.cocis.2013.04.008] [Citation(s) in RCA: 99] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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24
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Vissers T, Preisler Z, Smallenburg F, Dijkstra M, Sciortino F. Predicting crystals of Janus colloids. J Chem Phys 2013; 138:164505. [DOI: 10.1063/1.4801438] [Citation(s) in RCA: 82] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
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25
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Morris VK, Kwan AH, Sunde M. Analysis of the structure and conformational states of DewA gives insight into the assembly of the fungal hydrophobins. J Mol Biol 2012; 425:244-56. [PMID: 23137797 DOI: 10.1016/j.jmb.2012.10.021] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2012] [Revised: 10/10/2012] [Accepted: 10/30/2012] [Indexed: 11/19/2022]
Abstract
The hydrophobin DewA from the fungus Aspergillus nidulans is a highly surface-active protein that spontaneously self-assembles into amphipathic monolayers at hydrophobic:hydrophilic interfaces. These monolayers are composed of fibrils that are a form of functional amyloid. While there has been significant interest in the use of DewA for a variety of surface coatings and as an emulsifier in biotechnological applications, little is understood about the structure of the protein or the mechanism of self-assembly. We have solved the solution NMR structure of DewA. While the pattern of four disulfide bonds that is a defining feature of hydrophobins is conserved, the arrangement and composition of secondary-structure elements in DewA are quite different to what has been observed in other hydrophobin structures. In addition, we demonstrate that DewA populates two conformations in solution, both of which are assembly competent. One conformer forms a dimer at high concentrations, but this dimer is off-pathway to fibril formation and may represent an assembly control mechanism. These data highlight the structural differences between fibril-forming hydrophobins and those that form amorphous monolayers. This work will open up new opportunities for the engineering of hydrophobins with novel biotechnological applications.
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Affiliation(s)
- Vanessa K Morris
- School of Molecular Bioscience, University of Sydney, NSW 2006, Australia
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26
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Interfacial layers from the protein HFBII hydrophobin: Dynamic surface tension, dilatational elasticity and relaxation times. J Colloid Interface Sci 2012; 376:296-306. [PMID: 22480400 DOI: 10.1016/j.jcis.2012.03.031] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2011] [Revised: 02/12/2012] [Accepted: 03/12/2012] [Indexed: 11/21/2022]
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27
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Gruner LJ, Ostermann K, Rödel G. Layer thickness of hydrophobin films leads to oscillation in wettability. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:6942-6949. [PMID: 22458322 DOI: 10.1021/la204252y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
In nanobiotechnology, the properties of surfaces are often key to sensor applications. If analytes possess a low tolerance or affinity regarding the sensory substrate (surface), then the setup of mediators may be indicated. Hydrophobins enable biocompatible surface functionalization without significant restrictions of the physicochemical substrate properties. Because of the imperfect formation of hydrophobin films, a high variation in surface properties is observed. In this study, we report on the relation between the film thickness of hydrophobin-coated solid surfaces and their wettability. We found that the wettability of protein-coated surfaces strictly depends on the amount of adsorbed protein, as reflected in an oscillation of the contact angles of hydrophobin-coated silicon wafers. Fusion proteins of Ccg2 and HFBI, representatives of class I and II hydrophobins, document the influence of fused peptide tags on the wettability. The orientation of the first crystal nuclei plays a decisive role in the formation of the growing hydrophobin layers. Here, a simple method of deducing the film thickness of hydrophobin assemblies on solid surfaces is presented. The determination of the static contact angle allows the prediction of which part of the protein is exposed to possible analytes.
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Affiliation(s)
- Leopold J Gruner
- Institute of Genetics, Technische Universität Dresden, 01217 Dresden, Germany.
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Radulova GM, Golemanov K, Danov KD, Kralchevsky PA, Stoyanov SD, Arnaudov LN, Blijdenstein TBJ, Pelan EG, Lips A. Surface shear rheology of adsorption layers from the protein HFBII hydrophobin: effect of added β-casein. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:4168-4177. [PMID: 22320311 DOI: 10.1021/la205113w] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The surface shear rheology of hydrophobin HFBII adsorption layers is studied in angle-ramp/relaxation regime by means of a rotational rheometer. The behavior of the system is investigated at different shear rates and concentrations of added β-casein. In angle-ramp regime, the experimental data comply with the Maxwell model of viscoelastic behavior. From the fits of the rheological curves with this model, the surface shear elasticity and viscosity, E(sh) and η(sh), are determined at various fixed shear rates. The dependence of η(sh) on the rate of strain obeys the Herschel-Bulkley law. The data indicate an increasing fluidization (softening) of the layers with the rise of the shear rate. The addition of β-casein leads to more rigid adsorption layers, which exhibit a tendency of faster fluidization at increasing shear rates. In relaxation regime, the system obeys a modified Andrade's (cubic root) law, with two characteristic relaxation times. The fact that the data comply with the Maxwell model in angle-ramp regime, but follow the modified Andrade's low in relaxation regime, can be explained by the different processes occurring in the viscoelastic protein adsorption layer in these two regimes: breakage and restoration of intermolecular bonds at angle-ramp vs solidification of the layer at relaxation.
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Affiliation(s)
- Gergana M Radulova
- Department of Chemical Engineering, Faculty of Chemistry, Sofia University, Sofia, Bulgaria
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29
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D’Orsogna MR, Lakatos G, Chou T. Stochastic self-assembly of incommensurate clusters. J Chem Phys 2012; 136:084110. [DOI: 10.1063/1.3688231] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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30
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Zhang XL, Penfold J, Thomas RK, Tucker IM, Petkov JT, Bent J, Cox A, Grillo I. Self-assembly of hydrophobin and hydrophobin/surfactant mixtures in aqueous solution. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2011; 27:10514-10522. [PMID: 21774527 DOI: 10.1021/la2020226] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The self-assembly of the protein hydrophobin, HFBII, and its self-assembly with cationic, anionic, and nonionic surfactants hexadecylterimethyl ammonium bromide, CTAB, sodium dodecyl sulfate, SDS, and hexaethylene monododecyl ether, C(12)E(6), in aqueous solution have been studied by small-angle neutron scattering, SANS. HFBII self-assembles in solution as small globular aggregates, consistent with the formation of trimers or tetramers. Its self-assembly is not substantially affected by the pH or electrolytes. In the presence of CTAB, SDS, or C(12)E(6), HFBII/surfactant complexes are formed. The structure of the HFBII/surfactant complexes has been identified using contrast variation and is in the form of HFBII molecules bound to the outer surface of globular surfactant micelles. The binding of HFBII decreases the surfactant micelle aggregation number for increasing HFBII concentration in solution, and the number of hydrophobin molecules bound/micelle increases.
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Affiliation(s)
- Xiaoli L Zhang
- Physical and Theoretical Chemistry Laboratory, Oxford University, South Parks Road, Oxford, UK
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31
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Basheva ES, Kralchevsky PA, Danov KD, Stoyanov SD, Blijdenstein TBJ, Pelan EG, Lips A. Self-assembled bilayers from the protein HFBII hydrophobin: nature of the adhesion energy. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2011; 27:4481-4488. [PMID: 21413726 DOI: 10.1021/la2001943] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The hydrophobins are a class of amphiphilic proteins which spontaneously adsorb at the air/water interface and form elastic membranes of high mechanical strength as compared to other proteins. The mechanism of hydrophobin adhesion is of interest for fungal biology and for various applications in electronics, medicine, and food industry. We established that the drainage of free foam films formed from HFBII hydrophobin solutions ends with the appearance of a 6 nm thick film, which consists of two layers of protein molecules, that is, it is a self-assembled bilayer (S-bilayer), with hydrophilic domains pointing inward and hydrophobic domains pointing outward. Its formation is accompanied by a considerable energy gain, which is much greater than that typically observed with free liquid films. The experiments at different pH show that this attraction between the "hydrophilic" parts of the HFBII molecules is dominated by the short-range hydrophobic interaction rather than by the patch-charge electrostatic attraction.
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Affiliation(s)
- Elka S Basheva
- Department of Chemical Engineering, Faculty of Chemistry, Sofia University, 1164 Sofia, Bulgaria
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32
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Basheva ES, Kralchevsky PA, Christov NC, Danov KD, Stoyanov SD, Blijdenstein TBJ, Kim HJ, Pelan EG, Lips A. Unique properties of bubbles and foam films stabilized by HFBII hydrophobin. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2011; 27:2382-2392. [PMID: 21319779 DOI: 10.1021/la104726w] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The HFBII hydrophobin is an amphiphilic protein that can irreversibly adsorb at the air/water interface. The formed protein monolayers can reach a state of two-dimensional elastic solid that exhibits a high mechanical strength as compared to adsorption layers of typical amphiphilic proteins. Bubbles formed in HFBII solutions preserve the nonspherical shape they had at the moment of solidification of their surfaces. The stirring of HFBII solutions leads to the formation of many bubbles of micrometer size. Measuring the electrophoretic mobility of such bubbles, the ζ-potential was determined. Upon compression, the HFBII monolayers form periodic wrinkles of wavelength 11.5 μm, which corresponds to bending elasticity k(c) = 1.1 × 10(-19) J. The wrinkled hydrophobin monolayers are close to a tension-free state, which prevents the Ostwald ripening and provides bubble longevity in HFBII stabilized foams. Films formed between two bubbles are studied by experiments in a capillary cell. In the absence of added electrolyte, the films are electrostatically stabilized. The appearance of protein aggregates is enhanced with the increase of the HFBII and electrolyte concentrations and at pH close to the isoelectric point. When the aggregate concentration is not too high (to block the film thinning), the films reach a state with 12 nm uniform thickness, which corresponds to two surface monolayers plus HFBII tetramers sandwiched between them. In water, the HFBII molecules can stick to each other not only by their hydrophobic moieties but also by their hydrophilic parts. The latter leads to the attachment of HFBII aggregates such as dimers, tetramers, and bigger ones to the interfacial adsorption monolayers, which provides additional stabilization of the liquid films.
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Affiliation(s)
- Elka S Basheva
- Department of Chemical Engineering, Faculty of Chemistry, Sofia University , 1164 Sofia, Bulgaria
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Characterisation of HFBII biosurfactant production and foam fractionation with and without antifoaming agents. Appl Microbiol Biotechnol 2011; 90:911-20. [DOI: 10.1007/s00253-011-3137-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2010] [Revised: 01/17/2011] [Accepted: 01/17/2011] [Indexed: 11/25/2022]
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34
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Zampieri F, Wösten HAB, Scholtmeijer K. Creating Surface Properties Using a Palette of Hydrophobins. MATERIALS 2010; 3:4607-4625. [PMID: 28883343 PMCID: PMC5445765 DOI: 10.3390/ma3094607] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/09/2010] [Revised: 08/20/2010] [Accepted: 09/03/2010] [Indexed: 01/25/2023]
Abstract
Small secreted proteins called hydrophobins play diverse roles in the life cycle of filamentous fungi. For example, the hydrophobin SC3 of Schizophyllum commune is involved in aerial hyphae formation, cell-wall assembly and attachment to hydrophobic surfaces. Hydrophobins are capable of self-assembly at a hydrophilic-hydrophobic interface, resulting in the formation of an amphipathic film. This amphipathic film can make hydrophobic surfaces of a liquid or a solid material wettable, while a hydrophilic surface can be turned into a hydrophobic one. These properties, among others, make hydrophobins of interest for medical and technical applications. For instance, hydrophobins can be used to purify proteins from complex mixtures; to reduce the friction of materials; to increase the biocompatibility of medical implants; to increase the solubility of water insoluble drugs; and to immobilize enzymes, for example, biosensor surfaces.
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Affiliation(s)
- Filippo Zampieri
- Microbiology, Institute of Biomembranes, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands.
- BiOMaDe Technology Foundation, Nijenborgh 4, 9747 AG Groningen, The Netherlands.
- Department of Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute (GBB), University of Groningen, PO Box 14, 9750 AA Haren, The Netherlands.
| | - Han A B Wösten
- Microbiology, Institute of Biomembranes, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands.
| | - Karin Scholtmeijer
- Microbiology, Institute of Biomembranes, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands.
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van Ruymbeke E, Vlassopoulos D, Mierzwa M, Pakula T, Charalabidis D, Pitsikalis M, Hadjichristidis N. Rheology and Structure of Entangled Telechelic Linear and Star Polyisoprene Melts. Macromolecules 2010. [DOI: 10.1021/ma902769s] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- E. van Ruymbeke
- FORTH, Institute of Electronic Structure & Laser, Heraklion, Crete, Greece
- Unité de Physique et Chimie des Hauts Polymères, Université catholique de Louvain, Louvain-la-Neuve, Belgium
| | - D. Vlassopoulos
- FORTH, Institute of Electronic Structure & Laser, Heraklion, Crete, Greece
- University of Crete, Department of Materials Science & Technology, Heraklion, Crete, Greece
| | - M. Mierzwa
- Silesian University, A.Chelkowski Institute of Physics, Katowice, Poland
- Max-Planck Institut für Polymerforschung, Mainz, Germany
| | - T. Pakula
- Max-Planck Institut für Polymerforschung, Mainz, Germany
| | - D. Charalabidis
- University of Athens, Department of Chemistry, Athens, Greece
| | - M. Pitsikalis
- University of Athens, Department of Chemistry, Athens, Greece
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Abstract
AbstractThe thiazol dye Thioflavin T (ThT), which is used to stain amyloid fibrils, was found to have strong inhibitory effects on both growth and conidiation of the deuteromycete Trichoderma viride at concentrations between 10–100 µg/ml (ca. 30–300 µmol/l). Thioflavin S (ThS), also known to stain amyloid fibrils, had no significant effect at these concentrations. Both stains yielded a fluorescence response, but their distributions were different. ThT was non-homogenously distributed throughout the cytoplasm, whereas ThS fluorescence was strongly bound to septal regions. The effect of ThT was studied on several model microorganisms. It exerted a strong inhibitory effect on Staphylococcus aureus (Gram-positive bacterium) (MIC=10 µmol/l), but the effect on Escherichia coli (Gram-negative bacterium) was one order of magnitude less pronounced. The effect on Candida albicans was also very strong (MIC=50 µmol/l). The dermatophytic fungus Microsporum gypseum and deuteromycete Alternaria alternata were less affected by ThT (MIC=250 µmol/l and >500 µmol/l, respectively). These results show that ThT could be a useful inhibitor of selected microorganisms, whereas ThS could be a useful agent for monitoring formation and maintenance of intrahyphal septa without inhibiting the growth of the microorganism.
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37
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Valo HK, Laaksonen PH, Peltonen LJ, Linder MB, Hirvonen JT, Laaksonen TJ. Multifunctional hydrophobin: toward functional coatings for drug nanoparticles. ACS NANO 2010; 4:1750-1758. [PMID: 20210303 DOI: 10.1021/nn9017558] [Citation(s) in RCA: 88] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Efficient delivery of nanosized drug formulations to the desired body sites is not always reached despite the rapid development of pharmaceutical nanotechnologies. In spite of the undoubted effect of the size for increased bioavailability and controlled drug delivery, submicrometer formulations also require a deeper level of design. The surface properties of the particles determine the stability of the particles, interactions with the body, and targeting potentials of drugs. Thus, the efficacy of the drug can be increased utilizing the surface layer of the nanoparticles. Influencing the surface characters of the drug is the main focus of the present work, which introduces a method for preparing nanoparticles with functional sites from low-solubility drugs using hydrophobin (HFB) proteins. Particles were prepared by precipitating a lipophilic drug (beclomethasone dipropionate) in water in the presence of the HFB proteins. Particle size below 200 nm could easily be reached with increasing HFB concentration. The particles were shown to be stable for at least 5 h in suspension, and they could be stored for longer periods of time after freeze-drying. Labeling studies using green fluorescent protein (GFP) genetically fused to a HFB clearly demonstrated that the surface of the nanoparticles was covered with the hydrophobins and that the surface could be further modified by utilizing fusion proteins. This provides a template for a variety of different functional surface-bound groups that could be tailored by modifying the hydrophilic side of the HFB via protein bioengineering. In this study, the combination of proteins and traditional pharmaceutical technology was used to synthesize functionalized protein-coated nanoparticles for drug delivery purposes.
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Affiliation(s)
- Hanna K Valo
- Division of Pharmaceutical Technology, P.O. Box 56, FI-00014, University of Helsinki, Finland.
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38
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Sciortino F, Giacometti A, Pastore G. Phase diagram of Janus particles. PHYSICAL REVIEW LETTERS 2009; 103:237801. [PMID: 20366173 DOI: 10.1103/physrevlett.103.237801] [Citation(s) in RCA: 125] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2009] [Indexed: 05/29/2023]
Abstract
We thoroughly investigate a simple model representative of the recently synthesized Janus particles, i.e., colloidal spherical particles whose surface is divided into two areas of different chemical composition. When the two surfaces are solvophilic and solvophobic, these particles constitute the simplest example of surfactants. The phase diagram includes a colloidal-poor (gas), colloidal-rich (liquid) demixing region, which is progressively suppressed by the insurgence of micelles, providing the first model in which micellization and phase separation are simultaneously observed. The coexistence curve is found to be negatively sloped in the temperature-pressure plane, suggesting that Janus particles can provide a colloidal system with anomalous thermodynamic behavior.
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Affiliation(s)
- Francesco Sciortino
- Dipartimento di Fisica, Università di Roma La Sapienza, Piazzale A. Moro 2, 00185 Roma, Italy
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Characterization of ordered aggregates of cerato-platanin and their involvement in fungus–host interactions. Biochim Biophys Acta Gen Subj 2009; 1790:1334-44. [DOI: 10.1016/j.bbagen.2009.07.014] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2009] [Revised: 06/25/2009] [Accepted: 07/10/2009] [Indexed: 11/19/2022]
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Hou S, Li X, Li X, Feng X. Coating of hydrophobins on three-dimensional electrospun poly(lactic-co-glycolic acid) scaffolds for cell adhesion. Biofabrication 2009; 1:035004. [PMID: 20811108 DOI: 10.1088/1758-5082/1/3/035004] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Surface modification with hydrophobins is very important for cell adhesion in its applications in biosensor fabrication. In this study, we modified the surface of three-dimensional electrospun poly(lactide-co-glycolide) (PLGA) scaffolds with hydrophobin HFBI and collagen, and investigated its applications for cell adhesion. We found that HFBI could not only improve the hydrophilicity of the three-dimensional electrospun PLGA scaffolds but also endow the electrospun PLGA scaffolds with water permeability. This permeability should be attributed to both the hydrophilicity of the modified PLGA surface and the large positive capillary effect induced by the microstructures. Further experiment indicated that HFBI modification could improve collagen immobilization on the electrospun PLGA scaffolds and the HFBI/collagen modified electrospun PLGA scaffolds showed higher efficiency in promoting cell adhesion than the native PLGA scaffolds. This finding should be of potential application in biosensor device fabrication.
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Affiliation(s)
- Sen Hou
- College of Life Science, Nankai University, Weijin Road 94, Tianjin, People's Republic of China
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Sbrana F, Fanelli D, Vassalli M, Carresi L, Scala A, Pazzagli L, Cappugi G, Tiribilli B. Progressive pearl necklace collapse mechanism for cerato-ulmin aggregation film. EUROPEAN BIOPHYSICS JOURNAL: EBJ 2009; 39:971-7. [DOI: 10.1007/s00249-009-0465-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2009] [Revised: 04/21/2009] [Accepted: 04/29/2009] [Indexed: 12/01/2022]
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Surface modification using a novel type I hydrophobin HGFI. Anal Bioanal Chem 2009; 394:783-9. [PMID: 19370343 DOI: 10.1007/s00216-009-2776-y] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2009] [Revised: 03/23/2009] [Accepted: 03/26/2009] [Indexed: 10/20/2022]
Abstract
Surface wettability conversion with hydrophobins is important for its applications in biodevices. In this work, the application of a type I hydrophobin HGFI in surface wettability conversion on mica, glass, and poly(dimethylsiloxane) (PDMS) was investigated. X-ray photoelectron spectroscopy (XPS) and water-contact-angle (WCA) measurements indicated that HGFI modification could efficiently change the surface wettability. Data also showed that self-assembled HGFI had better stability than type II hydrophobin HFBI. Protein patterning and the following immunoassay illustrated that surface modification with HGFI should be a feasible strategy for biosensor device fabrication.
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Kisko K, Szilvay GR, Vuorimaa E, Lemmetyinen H, Linder MB, Torkkeli M, Serimaa R. Self-assembled films of hydrophobin proteins HFBI and HFBII studied in situ at the air/water interface. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2009; 25:1612-1619. [PMID: 19093751 DOI: 10.1021/la803252g] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Hydrophobins are a group of surface-active fungal proteins known to adsorb to the air/water interface and self-assemble into highly crystalline films. We characterized the self-assembled protein films of two hydrophobins, HFBI and HFBII from Trichoderma reesei, directly at the air/water interface using Brewster angle microscopy, grazing-incidence X-ray diffraction, and reflectivity. Already in zero surface pressure, HFBI and HFBII self-assembled into micrometer-sized rafts containing hexagonally ordered two-dimensional crystallites with lattice constants of 55 A and 56 A, respectively. Increasing the pressure did not change the ordering of the proteins in the crystallites. According to the reflectivity measurements, the thicknesses of the hydrophobin films were 28 A (HFBI) and 24 A (HFBII) at 20 mN/m. The stable films could also be transferred to a silicon substrate. Modeling of the diffraction data indicated that both hydrophobin films contained six molecules in the unit cell, but the ordering of the molecules was somewhat different for HFBI and HFBII, suggesting specific protein-protein interactions.
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Affiliation(s)
- Kaisa Kisko
- Division of Materials Physics, Department of Physics, University of Helsinki, POB 64, FI-00014, Finland.
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Vargas WA, Djonović S, Sukno SA, Kenerley CM. Dimerization controls the activity of fungal elicitors that trigger systemic resistance in plants. J Biol Chem 2008; 283:19804-15. [PMID: 18487198 DOI: 10.1074/jbc.m802724200] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The soilborne fungus Trichoderma virens secretes a small protein (Sm1) that induces local and systemic defenses in plants. This protein belongs to the ceratoplatanin protein family and is mainly present as a monomer in culture filtrates. However, Hypocrea atroviride (the telomorph form of Trichoderma atroviride) secretes an Sm1-homologous protein, Epl1, with high levels of dimerization. Nonetheless, the molecular mechanisms involved in recognition and the signaling pathways involved in the induction of systemic resistance in plants are still unclear. In this report, we demonstrate that Sm1 and Epl1 are mainly produced as monomer and a dimer, respectively, in the presence of maize seedlings. The results presented show that the ability to induce plant defenses reside only in the monomeric form of both Sm1 and Epl1, and we demonstrate for the first time that the monomeric form of Epl1, likewise Sm1, induces defenses in maize plants. Biochemical analyses indicate that monomeric Sm1 is produced as a glycoprotein, but the glycosyl moiety is missing from its dimeric form, and Epl1 is produced as a nonglycosylated protein. Moreover, for Sm1 homologues in various fungal strains, there is a negative correlation between the presence of the glycosylation site and their ability to aggregate. We propose a subdivision in the ceratoplatanin protein family according to the presence of the glycosylation site and the ability of the proteins to aggregate. The data presented suggest that the elicitor's aggregation may control the Trichoderma-plant molecular dialogue and block the activation of induced systemic resistance in plants.
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Affiliation(s)
- Walter A Vargas
- Department of Plant Pathology and Microbiology, Texas A&M University, College Station, Texas 77843, USA
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Kisko K, Szilvay GR, Vainio U, Linder MB, Serimaa R. Interactions of hydrophobin proteins in solution studied by small-angle X-ray scattering. Biophys J 2008; 94:198-206. [PMID: 17827247 PMCID: PMC2134873 DOI: 10.1529/biophysj.107.112359] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2007] [Accepted: 08/15/2007] [Indexed: 11/18/2022] Open
Abstract
Hydrophobins are a group of very surface-active, fungal proteins known to self-assemble on various hydrophobic/hydrophilic interfaces. The self-assembled films coat fungal structures and mediate their attachment to surfaces. Hydrophobins are also soluble in water. Here, the association of hydrophobins HFBI and HFBII from Trichoderma reesei in aqueous solution was studied using small-angle x-ray scattering. Both HFBI and HFBII exist mainly as tetramers in solution in the concentration range 0.5-10 mg/ml. The assemblies of HFBII dissociate more easily than those of HFBI, which can tolerate changes of pH from 3 to 9 and temperatures in the range 5 degrees C-60 degrees C. The self-association of HFBI and HFBII is mainly driven by the hydrophobic effect, and addition of salts along the Hofmeister series promotes the formation of larger assemblies, whereas ethanol breaks the tetramers into monomers. The possibility that the oligomers in solution form the building blocks of the self-assembled film at the air/water interface is discussed.
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Affiliation(s)
- Kaisa Kisko
- Department of Physical Sciences, University of Helsinki, FI-00014 HU, Finland.
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48
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Qin M, Hou S, Wang L, Feng X, Wang R, Yang Y, Wang C, Yu L, Shao B, Qiao M. Two methods for glass surface modification and their application in protein immobilization. Colloids Surf B Biointerfaces 2007; 60:243-9. [PMID: 17681764 DOI: 10.1016/j.colsurfb.2007.06.018] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2007] [Revised: 06/15/2007] [Accepted: 06/20/2007] [Indexed: 11/29/2022]
Abstract
Protein immobilization is a crucial step in protein chip, biosensor, etc. Here, two methods to immobilize proteins on glass surface were analyzed, one is silanization method using 3-aminopropyltriethoxysilane (APTES), and the other is hydrophobin HFBI coating. The modified glass surfaces were characterized with X-ray photoelectron spectroscopy (XPS), water contact angle measurement (WCA) and immunoassay. The results of XPS and WCA illustrated that the surface property of glass can be changed by both the two methods. The following immunoassay using microcontact printing (microCP) verified that both methods could help protein immobilization effectively on glass slides. Compared with the amine treatment, it is concluded that hydrophobin self-assemblies is a simple and generic way for protein immobilization on glass slides, which has potential application in protein chips and biosensors.
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Affiliation(s)
- Ming Qin
- The Key Laboratory of Bioactive Materials, Ministry of Education, College of Life Science, Nankai University, Tianjin 300071, PR China
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Kostiainen MA, Szilvay GR, Lehtinen J, Smith DK, Linder MB, Urtti A, Ikkala O. Precisely defined protein-polymer conjugates: construction of synthetic DNA binding domains on proteins by using multivalent dendrons. ACS NANO 2007; 1:103-113. [PMID: 19206526 DOI: 10.1021/nn700053y] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Nature has evolved proteins and enzymes to carry out a wide range of sophisticated tasks. Proteins modified with functional polymers possess many desirable physical and chemical properties and have applications in nanobiotechnology. Here we describe multivalent Newkome-type polyamine dendrons that function as synthetic DNA binding domains, which can be conjugated with proteins. These polyamine dendrons employ naturally occurring spermine surface groups to bind DNA with high affinity and are attached onto protein surfaces in a site-specific manner to yield well-defined one-to-one protein-polymer conjugates, where the number of dendrons and their attachment site on the protein surface are precisely known. This precise structure is achieved by using N-maleimido-core dendrons that selectively react via 1,4-conjugate addition with a single free thiol group on the protein surface--either Cys-34 of bovine serum albumin (BSA) or a genetically engineered cysteine mutant of Class II hydrophobin (HFBI). This reaction can be conducted in mild aqueous solutions (pH 7.2-7.4) and at ambient temperature, resulting in BSA- and HFBI-dendron conjugates. The protein-dendron conjugates constitute a specific biosynthetic diblock copolymer and bind DNA with high affinity, as shown by ethidium bromide displacement assay. Importantly, even the low-molecular-weight first-generation polyamine dendron (1 kDa) can bind a large BSA protein (66.4 kDa) to DNA with relatively good affinity. Preliminary gene transfection, cytotoxicity, and self-assembly studies establish the relevance of this methodology for in vitro applications, such as gene therapy and surface patterning. These results encourage further developments in protein-dendron block copolymer-like conjugates and will allow the advance of functional biomimetic nanoscale materials.
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Affiliation(s)
- Mauri A Kostiainen
- Department of Engineering, Physics, and Mathematics and Center for New Materials, Helsinki University of Technology, P.O. Box 2200, 02015 HUT, Espoo, Finland.
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Sunde M, Kwan AHY, Templeton MD, Beever RE, Mackay JP. Structural analysis of hydrophobins. Micron 2007; 39:773-84. [PMID: 17875392 DOI: 10.1016/j.micron.2007.08.003] [Citation(s) in RCA: 164] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2007] [Revised: 08/07/2007] [Accepted: 08/07/2007] [Indexed: 11/30/2022]
Abstract
Hydrophobins are a remarkable class of small cysteine-rich proteins found exclusively in fungi. They self-assemble to form robust polymeric monolayers that are highly amphipathic and play numerous roles in fungal biology, such as in the formation and dispersal of aerial spores and in pathogenic and mutualistic interactions. The polymeric form can be reversibly disassembled and is able to reverse the wettability of a surface, leading to many proposals for nanotechnological applications over recent years. The surprising properties of hydrophobins and their potential for commercialization have led to substantial efforts to delineate their morphology and molecular structure. In this review, we summarize the progress that has been made using a variety of spectroscopic and microscopic approaches towards understanding the molecular mechanisms underlying hydrophobin structure.
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Affiliation(s)
- Margaret Sunde
- School of Molecular and Microbial Biosciences, University of Sydney, Sydney 2006, Australia
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