1
|
Arnaouteli S, Bamford NC, Brandani GB, Morris RJ, Schor M, Carrington JT, Hobley L, van Aalten DMF, Stanley-Wall NR, MacPhee CE. Lateral interactions govern self-assembly of the bacterial biofilm matrix protein BslA. Proc Natl Acad Sci U S A 2023; 120:e2312022120. [PMID: 37903266 PMCID: PMC7615278 DOI: 10.1073/pnas.2312022120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Accepted: 09/11/2023] [Indexed: 11/01/2023] Open
Abstract
The soil bacterium Bacillus subtilis is a model organism to investigate the formation of biofilms, the predominant form of microbial life. The secreted protein BslA self-assembles at the surface of the biofilm to give the B. subtilis biofilm its characteristic hydrophobicity. To understand the mechanism of BslA self-assembly at interfaces, here we built a molecular model based on the previous BslA crystal structure and the crystal structure of the BslA paralogue YweA that we determined. Our analysis revealed two conserved protein-protein interaction interfaces supporting BslA self-assembly into an infinite 2-dimensional lattice that fits previously determined transmission microscopy images. Molecular dynamics simulations and in vitro protein assays further support our model of BslA elastic film formation, while mutagenesis experiments highlight the importance of the identified interactions for biofilm structure. Based on this knowledge, YweA was engineered to form more stable elastic films and rescue biofilm structure in bslA deficient strains. These findings shed light on protein film assembly and will inform the development of BslA technologies which range from surface coatings to emulsions in fast-moving consumer goods.
Collapse
Affiliation(s)
- Sofia Arnaouteli
- Division of Molecular Microbiology, School of Life Sciences, University of Dundee, DundeeDD5 4EH, United Kingdom
| | - Natalie C. Bamford
- Division of Molecular Microbiology, School of Life Sciences, University of Dundee, DundeeDD5 4EH, United Kingdom
| | - Giovanni B. Brandani
- Department of Biophysics, Graduate School of Science, Kyoto University, Kyoto606 8501, Japan
| | - Ryan J. Morris
- National Biofilms Innovation Centre, School of Physics & Astronomy, University of Edinburgh, EdinburghEH9 3FD, United Kingdom
| | - Marieke Schor
- UB Education, Content & Support, Maastricht University, Maastricht6211 LK, Netherlands
| | - Jamie T. Carrington
- Sir William Dunn School of Pathology, University of Oxford, OxfordOX1 3RE, United Kingdom
| | - Laura Hobley
- School of Biosciences, University of Nottingham, NottinghamNG7 2RD, United Kingdom
| | - Daan M. F. van Aalten
- Division of Molecular Microbiology, School of Life Sciences, University of Dundee, DundeeDD5 4EH, United Kingdom
- Department of Molecular Biology and Genetics, University of Aarhus, Aarhus8000, Denmark
| | - Nicola R. Stanley-Wall
- Division of Molecular Microbiology, School of Life Sciences, University of Dundee, DundeeDD5 4EH, United Kingdom
| | - Cait E. MacPhee
- National Biofilms Innovation Centre, School of Physics & Astronomy, University of Edinburgh, EdinburghEH9 3FD, United Kingdom
| |
Collapse
|
2
|
Zhang JG, Xu SY, Ying SH, Feng MG. Only one of three hydrophobins (Hyd1-3) contributes to conidial hydrophobicity and insect pathogenicity of Metarhizium robertsii. J Invertebr Pathol 2023; 201:108006. [PMID: 37844657 DOI: 10.1016/j.jip.2023.108006] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Revised: 09/22/2023] [Accepted: 10/12/2023] [Indexed: 10/18/2023]
Abstract
Class I/II hydrophobins constitute a family of small amphiphilic proteins that mediate cell hydrophobicity and adhesion to host or substrata and have pleiotropic effects in filamentous fungi. Here we report that only class I Hyd1 is essential for conidial hydrophobicity and insect pathogenicity among three hydrophobins (Hyd1-3) characterized in Metarhizium robertsii, an insect-pathogenic fungus. Aerial conidiation levels of three Δhyd1 mutants were much more reduced in 5-day-old cultures than in 7-day-old cultures, which were wettable (hydrophilic), but restored to a wild-type level in 15-day-old cultures. The Δhyd1 mutants were compromised in conidial quality, including significant decreases in hydrophobicity (58%), adhesion to insect cuticle (36%), insect pathogenicity via normal cuticle infection (37%), UVB resistance (20%), and heat tolerance (10%). In contrast, none of all examined phenotypes were affected in the null mutants of hyd2 and hyd3. Intriguingly, micromorphology and integrity of hydrophobin rodlet bundles on conidial coat were not affected in all mutant and wild-type strains, but the rodlet bundles were disordered in the absence of hyd1, suggesting a link of the disorder to the decreased hydrophobicity. Therefore, Hyd1 mediates the fungal hydrophobicity and plays an important role in conidial quality control and insect-pathogenic lifecycle. Class I Hyd2 and class II Hyd3 seem functionally redundant in M. robertsii.
Collapse
Affiliation(s)
- Jin-Guan Zhang
- Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Si-Yuan Xu
- Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Sheng-Hua Ying
- Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Ming-Guang Feng
- Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou 310058, China.
| |
Collapse
|
3
|
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.
Collapse
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.
| |
Collapse
|
4
|
Effective adsorption of nisin on the surface of polystyrene using hydrophobin HGFI. Int J Biol Macromol 2021; 173:399-408. [PMID: 33454334 DOI: 10.1016/j.ijbiomac.2021.01.052] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 12/25/2020] [Accepted: 01/08/2021] [Indexed: 11/24/2022]
Abstract
Herein, a new method was demonstrated for effective immobilization of the antibacterial peptide nisin on Grifola frondosa hydrophobin (HGFI), without the need of any additional complex reaction. Hydrophobin can self-assemble as a monolayer to form continuous negative-charged surfaces with enhanced wettability and biocompatibility. Adding nisin solution to such hydrophobin surface created antibacterial surfaces. The quantification analysis revealed that more nisin could be adsorbed on the HGFI-coated than to control polystyrene surfaces at different pH values. This suggested that electronic attraction and wettability may play important roles in this process. The transmission electron microscopy, atomic force microscopy and fourier transform infrared (FTIR) analysis indicated the adsorption mode of nisin on the HGFI film, i.e., hydrophobins served as an adhesive layer for binding charged peptides to interfaces. The antibacterial activity of the treated surface was investigated via counting, a nucleic acid release test, scanning electron microscopy, and biofilm detection. These results indicated the excellent antibacterial activity of nisin adsorbed on the HGFI-coated surfaces. The activity retention of adsorbed nisin was demonstrated by immersing the modified substrates in a flowed liquid condition.
Collapse
|
5
|
Hähl H, Griffo A, Safaridehkohneh N, Heppe J, Backes S, Lienemann M, Linder MB, Santen L, Laaksonen P, Jacobs K. Dynamic Assembly of Class II Hydrophobins from T. reesei at the Air-Water Interface. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:9202-9212. [PMID: 31268722 DOI: 10.1021/acs.langmuir.9b01078] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Class II hydrophobins are amphiphilic proteins produced by filamentous fungi. One of their typical features is the tendency to accumulate at the interface between an aqueous phase and a hydrophobic phase, such as the air-water interface. The kinetics of the interfacial self-assembly of wild-type hydrophobins HFBI and HFBII and some of their engineered variants at the air-water interface were measured by monitoring the accumulated mass at the interface via nondestructive ellipsometry measurements. The resulting mass vs time curves revealed unusual kinetics for a monolayer formation that did not follow a typical Langmuir-type of behavior but had a rather coverage-independent rate instead. Typically, the full surface coverage was obtained at masses corresponding to a monolayer. The formation of multilayers was not observed. Atomic force microscopy revealed formation and growth of non-fusing protein clusters at the interface. The mechanism of the adsorption was studied by varying the structure or charges of the protein or the ionic strength of the subphase, revealing that the lateral interactions between the hydrophobins play a role in their interfacial assembly. Additionally, a theoretical model was introduced to identify the underlying mechanism of the unconventional adsorption kinetics.
Collapse
Affiliation(s)
| | - Alessandra Griffo
- Department of Bioproducts and Biosystems , Aalto University , P.O. Box 16100, FI-00076 Aalto , Finland
| | | | | | - Sebastian Backes
- Federal Institute for Material Research and Testing (BAM) , Unter den Eichen 87 , 12205 Berlin , Germany
| | - Michael Lienemann
- VTT Technical Research Centre of Finland Ltd. , Espoo 02150 , Finland
| | - Markus B Linder
- Department of Bioproducts and Biosystems , Aalto University , P.O. Box 16100, FI-00076 Aalto , Finland
| | | | - Päivi Laaksonen
- Department of Bioproducts and Biosystems , Aalto University , P.O. Box 16100, FI-00076 Aalto , Finland
- HAMK Tech, Häme University of Applied Sciences , P.O. Box 230, Hämeenlinna 13101 , Finland
| | | |
Collapse
|
6
|
Yang J, Wang B, Ge L, Yang X, Wang X, Dai Y, Niu B, Xu H, Qiao M. The enhancement of surface activity and nanoparticle stability through the alteration of charged amino acids of HGFI. Colloids Surf B Biointerfaces 2019; 175:703-712. [DOI: 10.1016/j.colsurfb.2018.12.044] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Revised: 12/15/2018] [Accepted: 12/17/2018] [Indexed: 11/24/2022]
|
7
|
Berger BW, Sallada ND. Hydrophobins: multifunctional biosurfactants for interface engineering. J Biol Eng 2019; 13:10. [PMID: 30679947 PMCID: PMC6343262 DOI: 10.1186/s13036-018-0136-1] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Accepted: 12/19/2018] [Indexed: 11/10/2022] Open
Abstract
Hydrophobins are highly surface-active proteins that have versatile potential as agents for interface engineering. Due to the large and growing number of unique hydrophobin sequences identified, there is growing potential to engineer variants for particular applications using protein engineering and other approaches. Recent applications and advancements in hydrophobin technologies and production strategies are reviewed. The application space of hydrophobins is large and growing, including hydrophobic drug solubilization and delivery, protein purification tags, tools for protein and cell immobilization, antimicrobial coatings, biosensors, biomineralization templates and emulsifying agents. While there is significant promise for their use in a wide range of applications, developing new production strategies is a key need to improve on low recombinant yields to enable their use in broader applications; further optimization of expression systems and yields remains a challenge in order to use designed hydrophobin in commercial applications.
Collapse
Affiliation(s)
- Bryan W. Berger
- Department of Biomedical Engineering, University of Virginia, Thornton Hall, P.O. Box 400259, Charlottesville, VA 22904 USA
- Department of Chemical Engineering, University of Virginia, 214 Chem. Eng., 102 Engineers’ Way, Charlottesville, VA 22904 USA
| | - Nathanael D. Sallada
- Department of Biomedical Engineering, University of Virginia, Thornton Hall, P.O. Box 400259, Charlottesville, VA 22904 USA
| |
Collapse
|
8
|
Hähl H, Vargas JN, Jung M, Griffo A, Laaksonen P, Lienemann M, Jacobs K, Seemann R, Fleury JB. Adhesion Properties of Freestanding Hydrophobin Bilayers. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:8542-8549. [PMID: 29886739 DOI: 10.1021/acs.langmuir.8b00575] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Hydrophobins are a family of small-sized proteins featuring a distinct hydrophobic patch on the protein's surface, rendering them amphiphilic. This particularity allows hydrophobins to self-assemble into monolayers at any hydrophilic/hydrophobic interface. Moreover, stable pure protein bilayers can be created from two interfacial hydrophobin monolayers by contacting either their hydrophobic or their hydrophilic sides. In this study, this is achieved via a microfluidic approach, in which also the bilayers' adhesion energy can be determined. This enables us to study the origin of the adhesion of hydrophobic and hydrophilic core bilayers made from the class II hydrophobins HFBI and HFBII. Using different fluid media in this setup and introducing genetically modified variants of the HFBI molecule, the different force contributions to the adhesion of the bilayer sheets are studied. It was found that in the hydrophilic contact situation, the adhesive interaction was higher than that in the hydrophobic contact situation and could be even enhanced by reducing the contributions of electrostatic interactions. This effect indicates that the van der Waals interaction is the dominant contribution that explains the stability of the observed bilayers.
Collapse
Affiliation(s)
- Hendrik Hähl
- Department of Experimental Physics and Center for Biophysics , Saarland University , D-66123 Saarbrücken , Germany
| | - Jose Nabor Vargas
- Department of Experimental Physics and Center for Biophysics , Saarland University , D-66123 Saarbrücken , Germany
| | - Michael Jung
- Department of Experimental Physics and Center for Biophysics , Saarland University , D-66123 Saarbrücken , Germany
| | - Alessandra Griffo
- Department of Bioproducts and Biosystems BIO2 , Aalto University , P.O. Box 16100, 00076 Aalto , Finland
| | - Päivi Laaksonen
- Department of Bioproducts and Biosystems BIO2 , Aalto University , P.O. Box 16100, 00076 Aalto , Finland
| | - Michael Lienemann
- VTT Technical Research Centre of Finland Ltd. , Tietotie 2 , 02150 Espoo , Finland
| | - Karin Jacobs
- Department of Experimental Physics and Center for Biophysics , Saarland University , D-66123 Saarbrücken , Germany
| | - Ralf Seemann
- Department of Experimental Physics and Center for Biophysics , Saarland University , D-66123 Saarbrücken , Germany
| | - Jean-Baptiste Fleury
- Department of Experimental Physics and Center for Biophysics , Saarland University , D-66123 Saarbrücken , Germany
| |
Collapse
|
9
|
Li B, Wang X, Li Y, Paananen A, Szilvay GR, Qin M, Wang W, Cao Y. Single-Molecule Force Spectroscopy Reveals Self-Assembly Enhanced Surface Binding of Hydrophobins. Chemistry 2018; 24:9224-9228. [PMID: 29687928 DOI: 10.1002/chem.201801730] [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: 04/08/2018] [Indexed: 01/26/2023]
Abstract
Hydrophobins have raised lots of interest as powerful surface adhesives. However, it remains largely unexplored how their strong and versatile surface adhesion is linked to their unique amphiphilic structural features. Here, we develop an AFM-based single-molecule force spectroscopy assay to quantitatively measure the binding strength of hydrophobin to various types of surfaces both in isolation and in preformed protein films. We find that individual class II hydrophobins (HFBI) bind strongly to hydrophobic surfaces but weakly to hydrophilic ones. After self-assembly into protein films, they show much stronger binding strength to both surfaces due to the cooperativity of different interactions at nanoscale. Such self-assembly enhanced surface binding may serve as a general design principle for synthetic bioactive adhesives.
Collapse
Affiliation(s)
- Bing Li
- Collaborative Innovation Center of Advanced Microstructures, National Laboratory of Solid State Microstructure, Department of Physics, Nanjing University, Nanjing, 210093, P. R. China
| | - Xin Wang
- Collaborative Innovation Center of Advanced Microstructures, National Laboratory of Solid State Microstructure, Department of Physics, Nanjing University, Nanjing, 210093, P. R. China
| | - Ying Li
- Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, School of Environmental Science and Engineering, Nanjing University of Information Science & Technology, Nanjing, Jiangsu, 210044, P. R. China
| | - Arja Paananen
- Industrial Biotechnology, VTT Technical Research Centre of Finland Ltd, 02044 VTT, Espoo, Finland
| | - Géza R Szilvay
- Industrial Biotechnology, VTT Technical Research Centre of Finland Ltd, 02044 VTT, Espoo, Finland
| | - Meng Qin
- Collaborative Innovation Center of Advanced Microstructures, National Laboratory of Solid State Microstructure, Department of Physics, Nanjing University, Nanjing, 210093, P. R. China
| | - Wei Wang
- Collaborative Innovation Center of Advanced Microstructures, National Laboratory of Solid State Microstructure, Department of Physics, Nanjing University, Nanjing, 210093, P. R. China
| | - Yi Cao
- Collaborative Innovation Center of Advanced Microstructures, National Laboratory of Solid State Microstructure, Department of Physics, Nanjing University, Nanjing, 210093, P. R. China
| |
Collapse
|
10
|
Zhang X, Kirby SM, Chen Y, Anna SL, Walker LM, Hung FR, Russo PS. Formation and elasticity of membranes of the class II hydrophobin Cerato-ulmin at oil-water interfaces. Colloids Surf B Biointerfaces 2018; 164:98-106. [DOI: 10.1016/j.colsurfb.2018.01.017] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Revised: 12/29/2017] [Accepted: 01/15/2018] [Indexed: 01/10/2023]
|
11
|
Sallada ND, Dunn KJ, Berger BW. A Structural and Functional Role for Disulfide Bonds in a Class II Hydrophobin. Biochemistry 2018; 57:645-653. [DOI: 10.1021/acs.biochem.7b01166] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Nathanael D. Sallada
- Department
of Bioengineering, Lehigh University, 111 Research Drive, Bethlehem, Pennsylvania 18015, United States
| | - Kerri J. Dunn
- Department
of Chemical and Biomolecular Engineering, Lehigh University, 111
Research Drive, Bethlehem, Pennsylvania 18015, United States
| | - Bryan W. Berger
- Department
of Chemical and Biomolecular Engineering, Lehigh University, 111
Research Drive, Bethlehem, Pennsylvania 18015, United States
- Department
of Bioengineering, Lehigh University, 111 Research Drive, Bethlehem, Pennsylvania 18015, United States
| |
Collapse
|
12
|
Griffo A, Hähl H, Grandthyll S, Müller F, Paananen A, Ilmén M, Szilvay GR, Landowski CP, Penttilä M, Jacobs K, Laaksonen P. Single-Molecule Force Spectroscopy Study on Modular Resilin Fusion Protein. ACS OMEGA 2017; 2:6906-6915. [PMID: 31457277 PMCID: PMC6644949 DOI: 10.1021/acsomega.7b01133] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Accepted: 09/26/2017] [Indexed: 05/05/2023]
Abstract
The adhesive and mechanical properties of a modular fusion protein consisting of two different types of binding units linked together via a flexible resilin-like-polypeptide domain are quantified. The adhesive domains have been constructed from fungal cellulose-binding modules (CBMs) and an amphiphilic hydrophobin HFBI. This study is carried out by single-molecule force spectroscopy, which enables stretching of single molecules. The fusion proteins are designed to self-assemble on the cellulose surface, leading into the submonolayer of proteins having the HFBI pointing away from the surface. A hydrophobic atomic force microscopy (AFM) tip can be employed for contacting and lifting the single fusion protein from the HFBI-functionalized terminus by the hydrophobic interaction between the tip surface and the hydrophobic patch of the HFBI. The work of rupture, contour length at rupture and the adhesion forces of the amphiphilic end domains are evaluated under aqueous environment at different pHs.
Collapse
Affiliation(s)
- Alessandra Griffo
- Department
of Bioproducts and Biosystems BIO, Aalto University, P.O. Box 16100, FI-00076 Aalto, Finland
| | - Hendrik Hähl
- Department
of Experimental Physics, Saarland University, 66123 Saarbrücken, Germany
| | - Samuel Grandthyll
- Department
of Experimental Physics, Saarland University, 66123 Saarbrücken, Germany
| | - Frank Müller
- Department
of Experimental Physics, Saarland University, 66123 Saarbrücken, Germany
| | - Arja Paananen
- VTT
Technical Research Centre of Finland, Tietotie 2, P.O. Box 1000, FI-02044 Espoo, Finland
| | - Marja Ilmén
- VTT
Technical Research Centre of Finland, Tietotie 2, P.O. Box 1000, FI-02044 Espoo, Finland
| | - Géza R. Szilvay
- VTT
Technical Research Centre of Finland, Tietotie 2, P.O. Box 1000, FI-02044 Espoo, Finland
| | | | - Merja Penttilä
- Department
of Bioproducts and Biosystems BIO, Aalto University, P.O. Box 16100, FI-00076 Aalto, Finland
- VTT
Technical Research Centre of Finland, Tietotie 2, P.O. Box 1000, FI-02044 Espoo, Finland
| | - Karin Jacobs
- Department
of Experimental Physics, Saarland University, 66123 Saarbrücken, Germany
| | - Päivi Laaksonen
- Department
of Bioproducts and Biosystems BIO, Aalto University, P.O. Box 16100, FI-00076 Aalto, Finland
| |
Collapse
|
13
|
Linke C, Drusch S. Pickering emulsions in foods - opportunities and limitations. Crit Rev Food Sci Nutr 2017; 58:1971-1985. [DOI: 10.1080/10408398.2017.1290578] [Citation(s) in RCA: 115] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- Christina Linke
- Department of Food Technology and Food Material Science, Technische Universität Berlin, Germany
| | - Stephan Drusch
- Department of Food Technology and Food Material Science, Technische Universität Berlin, Germany
| |
Collapse
|
14
|
A mutant of hydrophobin HGFI tuning the self-assembly behaviour and biosurfactant activity. Appl Microbiol Biotechnol 2017; 101:8419-8430. [DOI: 10.1007/s00253-017-8577-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Revised: 09/29/2017] [Accepted: 10/04/2017] [Indexed: 10/18/2022]
|
15
|
Meister K, Paananen A, Speet B, Lienemann M, Bakker HJ. Molecular Structure of Hydrophobins Studied with Site-Directed Mutagenesis and Vibrational Sum-Frequency Generation Spectroscopy. J Phys Chem B 2017; 121:9398-9402. [PMID: 28967753 PMCID: PMC5647563 DOI: 10.1021/acs.jpcb.7b08865] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Revised: 09/14/2017] [Indexed: 01/31/2023]
Abstract
Hydrophobins are surface-active fungal proteins that adsorb to the water-air interface and self-assemble into amphiphilic, water-repelling films that have a surface elasticity that is an order of magnitude higher than other molecular films. Here we use surface-specific sum-frequency generation spectroscopy (VSFG) and site-directed mutagenesis to study the properties of class I hydrophobin (HFBI) films from Trichoderma reesei at the molecular level. We identify protein specific HFBI signals in the frequency region 1200-1700 cm-1 that have not been observed in previous VSFG studies on proteins. We find evidence that the aspartic acid residue (D30) next to the hydrophobic patch is involved in lateral intermolecular protein interactions, while the two aspartic acid residues (D40, D43) opposite to the hydrophobic patch are primarily interacting with the water solvent.
Collapse
Affiliation(s)
- K. Meister
- AMOLF, Science Park 104, 1098 XG Amsterdam, The Netherlands
| | - A. Paananen
- VTT Technical Research Centre of Finland Ltd, Tietotie, FI-02150 Espoo, Finland
| | - B. Speet
- AMOLF, Science Park 104, 1098 XG Amsterdam, The Netherlands
| | - M. Lienemann
- VTT Technical Research Centre of Finland Ltd, Tietotie, FI-02150 Espoo, Finland
| | - H. J. Bakker
- AMOLF, Science Park 104, 1098 XG Amsterdam, The Netherlands
| |
Collapse
|
16
|
Meister K, Roeters SJ, Paananen A, Woutersen S, Versluis J, Szilvay GR, Bakker HJ. Observation of pH-Induced Protein Reorientation at the Water Surface. J Phys Chem Lett 2017; 8:1772-1776. [PMID: 28345915 PMCID: PMC5451149 DOI: 10.1021/acs.jpclett.7b00394] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Accepted: 03/27/2017] [Indexed: 05/23/2023]
Abstract
Hydrophobins are surface-active proteins that form a hydrophobic, water-repelling film around aerial fungal structures. They have a compact, particle-like structure, in which hydrophilic and hydrophobic regions are spatially separated. This surface property renders them amphiphilic and is reminiscent of synthetic Janus particles. Here we report surface-specific chiral and nonchiral vibrational sum-frequency generation spectroscopy (VSFG) measurements of hydrophobins adsorbed to their natural place of action, the air-water interface. We observe that hydrophobin molecules undergo a reversible change in orientation (tilt) at the interface when the pH is varied. We explain this local orientation toggle from the modification of the interprotein interactions and the interaction of hydrophobin with the water solvent, following the pH-induced change of the charge state of particular amino acids.
Collapse
Affiliation(s)
- Konrad Meister
- AMOLF, Science Park 104, 1098XG Amsterdam, The Netherlands
| | - Steven J. Roeters
- Van
’t Hoff Institute for Molecular Sciences, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
| | - Arja Paananen
- VTT
Technical Research Centre of Finland Ltd., PO. Box 1000, FI-02044 VTT Espoo, Finland
| | - Sander Woutersen
- Van
’t Hoff Institute for Molecular Sciences, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
| | - Jan Versluis
- AMOLF, Science Park 104, 1098XG Amsterdam, The Netherlands
| | - Géza R. Szilvay
- VTT
Technical Research Centre of Finland Ltd., PO. Box 1000, FI-02044 VTT Espoo, Finland
| | - Huib J. Bakker
- AMOLF, Science Park 104, 1098XG Amsterdam, The Netherlands
| |
Collapse
|
17
|
Grunér MS, Paananen A, Szilvay GR, Linder MB. The dynamics of multimer formation of the amphiphilic hydrophobin protein HFBII. Colloids Surf B Biointerfaces 2017; 155:111-117. [PMID: 28415028 DOI: 10.1016/j.colsurfb.2017.03.057] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Revised: 12/30/2016] [Accepted: 03/27/2017] [Indexed: 10/19/2022]
Abstract
Hydrophobins are surface-active proteins produced by filamentous fungi. They have amphiphilic structures and form multimers in aqueous solution to shield their hydrophobic regions. The proteins rearrange at interfaces and self-assemble into films that can show a very high degree of structural order. Little is known on dynamics of multimer interactions in solution and how this is affected by other components. In this work we examine the multimer dynamics by stopped-flow fluorescence measurements and Förster Resonance Energy Transfer (FRET) using the class II hydrophobin HFBII. The half-life of exchange in the multimer state was 0.9s at 22°C with an activation energy of 92kJ/mol. The multimer exchange process of HFBII was shown to be significantly affected by the closely related HFBI hydrophobin, lowering both activation energy and half-life for exchange. Lower molecular weight surfactants interacted in very selective ways, but other surface active proteins did not influence the rates of exchange. The results indicate that the multimer formation is driven by specific molecular interactions that distinguish different hydrophobins from each other.
Collapse
Affiliation(s)
- M S Grunér
- Department of Bioproducts and Biosystems, Aalto University, Kemistintie 1, 02150 Espoo, Finland; VTT Technical Research Centre of Finland Ltd, Tietotie 2, 02150 Espoo, Finland
| | - A Paananen
- VTT Technical Research Centre of Finland Ltd, Tietotie 2, 02150 Espoo, Finland
| | - G R Szilvay
- VTT Technical Research Centre of Finland Ltd, Tietotie 2, 02150 Espoo, Finland
| | - M B Linder
- Department of Bioproducts and Biosystems, Aalto University, Kemistintie 1, 02150 Espoo, Finland.
| |
Collapse
|
18
|
Hähl H, Vargas JN, Griffo A, Laaksonen P, Szilvay G, Lienemann M, Jacobs K, Seemann R, Fleury JB. Pure Protein Bilayers and Vesicles from Native Fungal Hydrophobins. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2017; 29:1602888. [PMID: 27740699 DOI: 10.1002/adma.201602888] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Revised: 08/16/2016] [Indexed: 05/21/2023]
Abstract
Pure protein bilayers and vesicles are formed using the native, fungal hydrophobin HFBI. Bilayers with hydrophobic (red) and hydrophilic (blue) core are produced and, depending on the type of core, vesicles in water, oily media, and even in air can be created using microfluidic jetting. Vesicles in water are even able to incorporate functional gramicidin A pores.
Collapse
Affiliation(s)
- Hendrik Hähl
- Department of Experimental Physics, Saarland University, 66123, Saarbrücken, Germany
| | - Jose Nabor Vargas
- Department of Experimental Physics, Saarland University, 66123, Saarbrücken, Germany
| | - Alessandra Griffo
- Department of Experimental Physics, Saarland University, 66123, Saarbrücken, Germany
- Department of Materials Science, Aalto University, P. O. Box 16100, 00076, Aalto, Finland
| | - Päivi Laaksonen
- Department of Materials Science, Aalto University, P. O. Box 16100, 00076, Aalto, Finland
| | - Géza Szilvay
- VTT Technical Research Centre of Finland Ltd, Tietotie 2, 02150, Espoo, Finland
| | - Michael Lienemann
- VTT Technical Research Centre of Finland Ltd, Tietotie 2, 02150, Espoo, Finland
| | - Karin Jacobs
- Department of Experimental Physics, Saarland University, 66123, Saarbrücken, Germany
| | - Ralf Seemann
- Department of Experimental Physics, Saarland University, 66123, Saarbrücken, Germany
| | - Jean-Baptiste Fleury
- Department of Experimental Physics, Saarland University, 66123, Saarbrücken, Germany
| |
Collapse
|
19
|
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.
Collapse
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:
| |
Collapse
|
20
|
Meister K, Bäumer A, Szilvay GR, Paananen A, Bakker HJ. Self-Assembly and Conformational Changes of Hydrophobin Classes at the Air-Water Interface. J Phys Chem Lett 2016; 7:4067-4071. [PMID: 27690211 DOI: 10.1021/acs.jpclett.6b01917] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We use surface-specific vibrational sum-frequency generation spectroscopy (VSFG) to study the structure and self-assembling mechanism of the class I hydrophobin SC3 from Schizophyllum commune and the class II hydrophobin HFBI from Trichoderma reesei. We find that both hydrophobins readily accumulate at the water-air interface and form rigid, highly ordered protein films that give rise to prominent VSFG signals. We identify several resonances that are associated with β-sheet structures and assign them to the central β-barrel core present in both proteins. Differences between the hydrophobin classes are observed in their interfacial self-assembly. For HFBI, we observe no changes in conformation upon adsorption to the water surface. For SC3, we observe an increase in β-sheet-specific signals that supports a surface-driven self-assembly mechanism in which the central β-barrel remains intact and stacks into a larger-scale architecture, amyloid-like rodlets.
Collapse
Affiliation(s)
- Konrad Meister
- FOM-Institute for Atomic and Molecular Physics AMOLF, Science Park 104, 1098 XG Amsterdam, The Netherlands
| | - Alexander Bäumer
- Physical Chemistry II, Ruhr University Bochum , Universitätsstr. 150, 44801 Bochum, Germany
| | - Geza R Szilvay
- VTT Technical Research Centre of Finland Ltd, Tietotie 2, FI-02150 Espoo, Finland
| | - Arja Paananen
- VTT Technical Research Centre of Finland Ltd, Tietotie 2, FI-02150 Espoo, Finland
| | - Huib J Bakker
- FOM-Institute for Atomic and Molecular Physics AMOLF, Science Park 104, 1098 XG Amsterdam, The Netherlands
| |
Collapse
|
21
|
Antony M S, Jaganathan M, Dhathathreyan A. Relevance of interfacial viscoelasticity in stability and conformation of biomolecular organizates at air/fluid interface. Adv Colloid Interface Sci 2016; 234:80-88. [PMID: 27174489 DOI: 10.1016/j.cis.2016.04.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Revised: 04/13/2016] [Accepted: 04/13/2016] [Indexed: 01/30/2023]
Abstract
Soft materials are complex macromolecular systems often exhibiting perplexing non-Newtonian viscoelastic properties, especially when the macromolecules are entangled, crowded or cross-linked. These materials are ubiquitous in the biology, food and pharma industry and have several applications in biotechnology and in the field of biosensors. Based on the length scales, topologies, flexibility and concentration, the systems behave both as liquids (viscous) and solids (elastic). Particularly, for proteins and protein-lipid systems, viscoelasticity is an important parameter because it often relates directly to stability and thermodynamic interactions of the pure biological components as well as their mixtures. Despite the large body of work that is available in solution macro-rheometry, there are still a number of issues that need to be addressed in dealing with proteins at air/fluid interfaces and with protein-polymer or protein-lipid interfaces that often exhibit very low interfacial viscosity values. Considering the important applications that they have in biopharmaceutical, biotechnological and nutraceutical industries, there is a need for developing methods that meet the following three specific issues: small volume, large dynamic range of shear rates and interfacial properties of different biomolecules. Further, the techniques that are developed should include Newtonian, shear thinning and yielding properties, which are representative of the different solution behaviors typically encountered. The review presented here is a comprehensive account of the rheological properties of different biomolecules at air/fluid and solid/fluid interfaces. It addresses the usefulness of 'viscoelasticity' of the systems at the interfaces analyzed at the molecular level that can be correlated with the microscopic material properties and touches upon some recent techniques in microrheology that are being used to measure the unusually low viscosity values sensitively.
Collapse
|
22
|
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.
Collapse
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.
| | | |
Collapse
|
23
|
Yamasaki R, Haruyama T. Formation Mechanism of Flattened Top HFBI Domical Droplets. J Phys Chem B 2016; 120:3699-704. [DOI: 10.1021/acs.jpcb.6b01306] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Ryota Yamasaki
- Advanced
Catalytic Transformation Program for Carbon Utilization (ACT-C), Japan Science and Technology Agency (JST), Tokyo 102-0076, Japan
| | - Tetsuya Haruyama
- Advanced
Catalytic Transformation Program for Carbon Utilization (ACT-C), Japan Science and Technology Agency (JST), Tokyo 102-0076, Japan
| |
Collapse
|
24
|
Yamasaki R, Takatsuji Y, Asakawa H, Fukuma T, Haruyama T. Flattened-Top Domical Water Drops Formed through Self-Organization of Hydrophobin Membranes: A Structural and Mechanistic Study Using Atomic Force Microscopy. ACS NANO 2016; 10:81-87. [PMID: 26595357 DOI: 10.1021/acsnano.5b04049] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The Trichoderma reesei hydrophobin, HFBI, is a unique structural protein. This protein forms membranes by self-organization at air/water or water/solid interfaces. When HFBI forms a membrane at an air/water interface, the top of the water droplet is flattened. The mechanism underlying this phenomenon has not been explored. In this study, this unique phenomenon has been investigated. Self-organized HFBI membranes form a hexagonal structured membrane on the surface of water droplets; the structure was confirmed by atomic force microscopy (AFM) measurement. Assembled hexagons can form a planar sheet or a tube. Self-organized HFBI membranes on water droplets form a sheet with an array of hexagonal structures or a honeycomb structure. This membrane, with its arrayed hexagonal structures, has very high buckling strength. We hypothesized that the high buckling strength is the reason that water droplets containing HFBI form flattened domes. To test this hypothesis, the strength of the self-organized HFBI membranes was analyzed using AFM. The buckling strength of HFBI membranes was measured to be 66.9 mN/m. In contrast, the surface tension of water droplets containing dissolved HFBI is 42 mN/m. Thus, the buckling strength of a self-organized HFBI membrane is higher than the surface tension of water containing dissolved HFBI. This mechanistic study clarifies why the water droplets formed by self-organized HFBI membranes have a flattened top.
Collapse
Affiliation(s)
- Ryota Yamasaki
- Advanced Catalytic Transformation Program for Carbon Utilization (ACT-C), Japan Science and Technology Agency (JST) , Tokyo 102-0076, Japan
| | - Yoshiyuki Takatsuji
- Advanced Catalytic Transformation Program for Carbon Utilization (ACT-C), Japan Science and Technology Agency (JST) , Tokyo 102-0076, Japan
| | - Hitoshi Asakawa
- Advanced Catalytic Transformation Program for Carbon Utilization (ACT-C), Japan Science and Technology Agency (JST) , Tokyo 102-0076, Japan
| | - Takeshi Fukuma
- Advanced Catalytic Transformation Program for Carbon Utilization (ACT-C), Japan Science and Technology Agency (JST) , Tokyo 102-0076, Japan
| | - Tetsuya Haruyama
- Advanced Catalytic Transformation Program for Carbon Utilization (ACT-C), Japan Science and Technology Agency (JST) , Tokyo 102-0076, Japan
| |
Collapse
|
25
|
Gene Expression Systems in Industrial Ascomycetes: Advancements and Applications. Fungal Biol 2016. [DOI: 10.1007/978-3-319-27951-0_1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
|