1
|
Gilbert RJC. Peptide-based pore formation and cell membrane deformation: European Biophysics Journal Prizes at EBSA 2023. EUROPEAN BIOPHYSICS JOURNAL : EBJ 2023; 52:619-623. [PMID: 37994943 DOI: 10.1007/s00249-023-01691-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2023]
Abstract
The European Biophysics Journal Prizes awarded at the European Biophysical Societies Association (EBSA) Congress in Stockholm in the Summer of 2023 recognised papers published in 2020 and 2021 which made use of multiple complementing experimental, theoretical and computational approaches. One of the winning papers addressed the specific role of arginine residues within antimicrobial and cell-penetrating peptides, in promoting membrane defect stabilisation and pore formation. The other winning paper described the influence of atomic force microscopy probe geometry on the measurement of surface deformability, assessed for investigation of the differing viscoelastic properties of non-malignant and cancerous cells. These papers showcase biophysical science; the importance of combining different experimental, modelling and molecular dynamics methods; and how researchers need to understand the theoretical basis and the limitations of the techniques they use. EBSA warmly congratulates the authors on their work and its subsequent recognition. Publication of these papers also demonstrates the ongoing commitment of the European Biophysics Journal to molecular scale and to systems biophysics, and to support of the international biophysical community.
Collapse
Affiliation(s)
- Robert J C Gilbert
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford, OX3 7BN, UK.
| |
Collapse
|
2
|
Zhang T, Guo Y, Fan X, Liu M, Xu J, Zeng X, Sun Y, Wu Z, Pan D. Protection Mechanism of Metal Ion Pre-Stress on Lactobacillus acidophilus CICC 6074 under Acid Tolerance. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2023; 71:13304-13315. [PMID: 37639527 DOI: 10.1021/acs.jafc.3c01970] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/31/2023]
Abstract
The prerequisite for the probiotic effect of lactic acid bacteria is that they could survive the acid stress environment of production and application. In this experiment, the mechanism for the effect of different metal ion pre-stress on the acid-tolerant survival of Lactobacillus was investigated. Scanning electron microscopy, Fourier infrared spectroscopy, and flow cytometry were used to analyze the condition of bacteria after acid treatment, which revealed that different metal ion pre-stress could improve the survival ability of Lactobacillus acidophilus CICC 6074 under low acid conditions by improving cell morphology, mitigating cell membrane damage, and regulating surface protein expression. Furthermore, Tandem Mass Tags (TMT) proteomic analysis revealed that Mn2+ pre-stress showed relatively more superior protective effects on acid tolerance in L. acidophilus CICC 6074 through activation of DNA replication, RNA synthesis, S-layer protein secretion, H+-ATPase enzyme activity, etc. This study will provide new ideas and a theoretical basis for the development and application of lactic acid bacteria.
Collapse
Affiliation(s)
- Tao Zhang
- Key Laboratory of Animal Protein Food Processing Technology of Zhejiang Province, College of Food and Pharmaceutical Sciences, Ningbo University, Ningbo 315211, China
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products, Ningbo University, Ningbo 315211, China
| | - Yuxing Guo
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing 210023, China
| | - Xiankang Fan
- Key Laboratory of Animal Protein Food Processing Technology of Zhejiang Province, College of Food and Pharmaceutical Sciences, Ningbo University, Ningbo 315211, China
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products, Ningbo University, Ningbo 315211, China
| | - Mingzhen Liu
- Key Laboratory of Animal Protein Food Processing Technology of Zhejiang Province, College of Food and Pharmaceutical Sciences, Ningbo University, Ningbo 315211, China
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products, Ningbo University, Ningbo 315211, China
| | - Jue Xu
- Key Laboratory of Animal Protein Food Processing Technology of Zhejiang Province, College of Food and Pharmaceutical Sciences, Ningbo University, Ningbo 315211, China
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products, Ningbo University, Ningbo 315211, China
| | - Xiaoqun Zeng
- Key Laboratory of Animal Protein Food Processing Technology of Zhejiang Province, College of Food and Pharmaceutical Sciences, Ningbo University, Ningbo 315211, China
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products, Ningbo University, Ningbo 315211, China
| | - Yangying Sun
- Key Laboratory of Animal Protein Food Processing Technology of Zhejiang Province, College of Food and Pharmaceutical Sciences, Ningbo University, Ningbo 315211, China
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products, Ningbo University, Ningbo 315211, China
| | - Zhen Wu
- Key Laboratory of Animal Protein Food Processing Technology of Zhejiang Province, College of Food and Pharmaceutical Sciences, Ningbo University, Ningbo 315211, China
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products, Ningbo University, Ningbo 315211, China
| | - Daodong Pan
- Key Laboratory of Animal Protein Food Processing Technology of Zhejiang Province, College of Food and Pharmaceutical Sciences, Ningbo University, Ningbo 315211, China
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products, Ningbo University, Ningbo 315211, China
| |
Collapse
|
3
|
Assandri MH, Malamud M, Trejo FM, Serradell MDLA. S-layer proteins as immune players: tales from pathogenic and non-pathogenic bacteria. CURRENT RESEARCH IN MICROBIAL SCIENCES 2023; 4:100187. [PMID: 37064268 PMCID: PMC10102220 DOI: 10.1016/j.crmicr.2023.100187] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/29/2023] Open
Abstract
In bacteria, as in other microorganisms, surface compounds interact with different pattern recognition receptors expressed by host cells, which usually triggers a variety of cellular responses that result in immunomodulation. The S-layer is a two-dimensional macromolecular crystalline structure formed by (glyco)-protein subunits that covers the surface of many species of Bacteria and almost all Archaea. In Bacteria, the presence of S-layer has been described in both pathogenic and non-pathogenic strains. As surface components, special attention deserves the role that S-layer proteins (SLPs) play in the interaction of bacterial cells with humoral and cellular components of the immune system. In this sense, some differences can be predicted between pathogenic and non-pathogenic bacteria. In the first group, the S-layer constitutes an important virulence factor, which in turn makes it a potential therapeutic target. For the other group, the growing interest to understand the mechanisms of action of commensal microbiota and probiotic strains has prompted the studies of the role of the S-layer in the interaction between the host immune cells and bacteria bearing this surface structure. In this review, we aim to summarize the main latest reports and the perspectives of bacterial SLPs as immune players, focusing on those from pathogenic and commensal/probiotic most studied species.
Collapse
|
4
|
Lactobacillus buchneri S-layer protein-coated liposomes loaded with β-cyclodextrin–carvacrol inclusion complexes for the enhancement of antibacterial effect. Food Res Int 2022; 160:111623. [DOI: 10.1016/j.foodres.2022.111623] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Revised: 06/17/2022] [Accepted: 07/04/2022] [Indexed: 11/21/2022]
|
5
|
Simon P, Pompe W, Gruner D, Sturm E, Ostermann K, Matys S, Vogel M, Rödel G. Nested Formation of Calcium Carbonate Polymorphs in a Bacterial Surface Membrane with a Graded Nanoconfinement: An Evolutionary Strategy to Ensure Bacterial Survival. ACS Biomater Sci Eng 2022; 8:526-539. [PMID: 34995442 PMCID: PMC8848282 DOI: 10.1021/acsbiomaterials.1c01280] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
![]()
It is the intention
of this study to elucidate the nested formation
of calcium carbonate polymorphs or polyamorphs in the different nanosized
compartments. With these observations, it can be concluded how the
bacteria can survive in a harsh environment with high calcium carbonate
supersaturation. The mechanisms of calcium carbonate precipitation
at the surface membrane and at the underlying cell wall membrane of
the thermophilic soil bacterium Geobacillus stearothermophilus DSM 13240 have been revealed by high-resolution transmission electron
microscopy and atomic force microscopy. In this Gram-positive bacterium,
nanopores in the surface layer (S-layer) and in the supporting cell
wall polymers are nucleation sites for metastable calcium carbonate
polymorphs and polyamorphs. In order to observe the different metastable
forms, various reaction times and a low reaction temperature (4 °C)
have been chosen. Calcium carbonate polymorphs nucleate in the confinement
of nanosized pores (⌀ 3–5 nm) of the S-layer. The hydrous
crystalline calcium carbonate (ikaite) is formed initially with [110]
as the favored growth direction. It transforms into the anhydrous
metastable vaterite by a solid-state transition. In a following reaction
step, calcite is precipitated, caused by dissolution of vaterite in
the aqueous solution. In the larger pores of the cell wall (⌀
20–50 nm), hydrated amorphous calcium carbonate is grown, which
transforms into metastable monohydrocalcite, aragonite, or calcite.
Due to the sequence of reaction steps via various metastable phases,
the bacteria gain time for chipping the partially mineralized S-layer,
and forming a fresh S-layer (characteristic growth time about 20 min).
Thus, the bacteria can survive in solutions with high calcium carbonate
supersaturation under the conditions of forced biomineralization.
Collapse
Affiliation(s)
- Paul Simon
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187 Dresden, Germany
| | - Wolfgang Pompe
- Institute of Materials Science, Technische Universität Dresden, Helmholtzstraße 7, 01069 Dresden, Germany
| | - Denise Gruner
- Institute of Genetics, Technische Universität Dresden, Zellescher Weg 20b, 01217 Dresden, Germany.,Polymeric Microsystems, Technische Universität Dresden, Helmholtzstraße 100, 01069 Dresden, Germany
| | - Elena Sturm
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187 Dresden, Germany.,Physical Chemistry, University of Konstanz, POB 714, D-78457 Konstanz, Germany
| | - Kai Ostermann
- Institute of Genetics, Technische Universität Dresden, Zellescher Weg 20b, 01217 Dresden, Germany
| | - Sabine Matys
- Helmholtz Institute Freiberg for Resource Technology, Helmholtz-Zentrum Dresden-Rossendorf, Bautzener Landstraße 400, 01328 Dresden, Germany
| | - Manja Vogel
- Helmholtz Institute Freiberg for Resource Technology, Helmholtz-Zentrum Dresden-Rossendorf, Bautzener Landstraße 400, 01328 Dresden, Germany
| | - Gerhard Rödel
- Institute of Genetics, Technische Universität Dresden, Zellescher Weg 20b, 01217 Dresden, Germany
| |
Collapse
|
6
|
Abstract
Bacterial surface layers (S-layers) have been observed as the outermost cell envelope component in a wide range of bacteria and most archaea. S-layers are monomolecular lattices composed of a single protein or glycoprotein species and have either oblique, square or hexagonal lattice symmetry with unit cell dimensions ranging from 3 to 30 nm. They are generally 5 to 10 nm thick (up to 70 nm in archaea) and represent highly porous protein lattices (30–70% porosity) with pores of uniform size and morphology in the range of 2 to 8 nm. Since S-layers can be considered as one of the simplest protein lattices found in nature and the constituent units are probably the most abundantly expressed proteins on earth, it seems justified to briefly review the different S-layer lattice types, the need for lattice imperfections and the discussion of S-layers from the perspective of an isoporous protein network in the ultrafiltration region. Finally, basic research on S-layers laid the foundation for applications in biotechnology, synthetic biology, and biomimetics.
Collapse
|
7
|
Moll H, Lehmann F, Raff J. Interaction of curium(III) with surface-layer proteins from Lysinibacillus sphaericus JG-A12. Colloids Surf B Biointerfaces 2020; 190:110950. [PMID: 32172166 DOI: 10.1016/j.colsurfb.2020.110950] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Revised: 02/28/2020] [Accepted: 03/05/2020] [Indexed: 11/18/2022]
Abstract
Trivalent actinides such as Cm(III) are able to occupy natural Ca(II) binding sites in biological systems. For this investigation, we studied the formation of aqueous Cm(III) complexes with S-layer proteins by time-resolved laser-induced fluorescence spectroscopy (TRLFS). S-layer proteins serve as protective biointerfaces in bacteria and archaea against the surrounding solution. Experimental assays were performed at a fixed total concentration of Cm(III) (0.88 μM) using an S-layer protein (5 g/L / 39.6 μM) at varying pH levels (2.0-9.0), as well as several types of S-layer proteins of L. sphaericus JG-A12. Based on resulting luminescence spectra and lifetime data, specific and unspecific binding sites could be distinguished. Notably, specific Cm(III) binding to S-layer proteins was confirmed by the appearance of a sharp emission band at 602.5 nm, combined with a long lifetime of 310 μs. The high affinity of these specific binding sites was also verified using competing EDTA, wherein only a high EDTA concentration (40 μM) could efficiently remove Cm(III) from S-layer proteins.
Collapse
Affiliation(s)
- Henry Moll
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Resource Ecology, Bautzner Landstraße 400, 01328 Dresden, Germany.
| | - Falk Lehmann
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Resource Ecology, Bautzner Landstraße 400, 01328 Dresden, Germany
| | - Johannes Raff
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Resource Ecology, Bautzner Landstraße 400, 01328 Dresden, Germany
| |
Collapse
|
8
|
Abstract
Focus a laser on dissolved particles and analyze the scattered light to reveal their size. This well established principle is used in dynamic light scattering (DLS), or also called photon-correlation spectroscopy, which is a widely popular and highly adaptable analytical method applied in different fields of life and material sciences, as well as in industrial quality control processes.
Collapse
Affiliation(s)
- Alice S. Pereira
- grid.10772.330000000121511713Molecular Biophysics Lab., UCIBIO/Requimte, Department of Chemistry, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, Caparica, Portugal
| | - Pedro Tavares
- grid.10772.330000000121511713Molecular Biophysics Lab., UCIBIO/Requimte, Department of Chemistry, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, Caparica, Portugal
| | - Paulo Limão-Vieira
- grid.10772.330000000121511713Atomic and Molecular Collisions Laboratory, CEFITEC, Department of Physics, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, Caparica, Portugal
| |
Collapse
|
9
|
Enhanced Gold Biosorption of Lysinibacillus sphaericus CBAM5 by Encapsulation of Bacteria in an Alginate Matrix. METALS 2019. [DOI: 10.3390/met9080818] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Given its variety of properties, including conductivity and slow corrosion, the industrial uses for gold are increasing dramatically. This means that greater amounts of gold are being released into the environment and that a biological approach to recycling gold is of great interest. Lysinibacillus sphaericus, a bacterium capable of metal accumulation inside the cell and adsorption in the external surface, was encapsulated in an alginate matrix to improve the capture of gold from aqueous media. In this study, L. sphaericus CBAM5 proved to have the greatest potential compared to other strains and, following its encapsulation, the efficiency for the removal of the precious metal, at a concentration of 60 ppm, was 100% after three hours of exposure. It was identified that the alginate spheres with bacteria could also be reused. In fact, an efficiency of 60% was retained after three cycles of utilization. Thus, alginate acts as an adequate immobilization matrix for bacteria as a highly effective gold capture mechanism, which also shows great potential as an alternative for biotechnological applications.
Collapse
|
10
|
Rodrigues-Oliveira T, Souza AA, Kruger R, Schuster B, Maria de Freitas S, Kyaw CM. Environmental factors influence the Haloferax volcanii S-layer protein structure. PLoS One 2019; 14:e0216863. [PMID: 31075115 PMCID: PMC6607943 DOI: 10.1371/journal.pone.0216863] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Accepted: 04/30/2019] [Indexed: 11/18/2022] Open
Abstract
S-layers commonly cover archaeal cell envelopes and are composed of proteins that self-assemble into a paracrystalline surface structure. Despite their detection in almost all archaea, there are few reports investigating the structural properties of these proteins, with no reports exploring this topic for halophilic S-layers. The objective of the present study was to investigate the secondary and tertiary organization of the Haloferax volcanii S-layer protein. Such investigations were performed using circular dichroism, fluorescence spectroscopy, dynamic light scattering and transmission electron microscopy. The protein secondary structure is centered on β-sheets and is affected by environmental pH, with higher disorder in more alkaline conditions. The pH can also affect the protein's tertiary structure, with higher tryptophan side-chain exposure to the medium under the same conditions. The concentrations of Na, Mg and Ca ions in the environment also affect the protein structures, with small changes in α-helix and β-sheet content, as well as changes in tryptophan side chain exposure. These changes in turn influence the protein's functional properties, with cell envelope preparations revealing striking differences when in different salt conditions. Thermal denaturation assays revealed that the protein is stable. It has been reported that the S-layer protein N-glycosylation process is affected by external factors and the present study indicates for the first time changes in the protein structure.
Collapse
Affiliation(s)
- Thiago Rodrigues-Oliveira
- Department of Cell Biology, Institute of Biological Sciences, University
of Brasília, Brasília, Brazil
| | - Amanda Araújo Souza
- Department of Cell Biology, Institute of Biological Sciences, University
of Brasília, Brasília, Brazil
| | - Ricardo Kruger
- Department of Cell Biology, Institute of Biological Sciences, University
of Brasília, Brasília, Brazil
| | - Bernhard Schuster
- Department of NanoBiotechnology, Institute for Synthetic
Bioarchitectures, University of Natural Resources and Life Sciences, Vienna,
Austria
| | - Sonia Maria de Freitas
- Department of Cell Biology, Institute of Biological Sciences, University
of Brasília, Brasília, Brazil
| | - Cynthia Maria Kyaw
- Department of Cell Biology, Institute of Biological Sciences, University
of Brasília, Brasília, Brazil
| |
Collapse
|
11
|
Luo G, Yang Q, Yao B, Tian Y, Hou R, Shao A, Li M, Feng Z, Wang W. Slp-coated liposomes for drug delivery and biomedical applications: potential and challenges. Int J Nanomedicine 2019; 14:1359-1383. [PMID: 30863066 PMCID: PMC6388732 DOI: 10.2147/ijn.s189935] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Slp forms a crystalline array of proteins on the outermost envelope of bacteria and archaea with a molecular weight of 40-200 kDa. Slp can self-assemble on the surface of liposomes in a proper environment via electrostatic interactions, which could be employed to functionalize liposomes by forming Slp-coated liposomes for various applications. Among the molecular characteristics, the stability, adhesion, and immobilization of biomacromolecules are regarded as the most meaningful. Compared to plain liposomes, Slp-coated liposomes show excellent physicochemical and biological stabilities. Recently, Slp-coated liposomes were shown to specifically adhere to the gastrointestinal tract, which was attributed to the "ligand-receptor interaction" effect. Furthermore, Slp as a "bridge" can immobilize functional biomacromol-ecules on the surface of liposomes via protein fusion technology or intermolecular forces, endowing liposomes with beneficial functions. In view of these favorable features, Slp-coated liposomes are highly likely to be an ideal platform for drug delivery and biomedical uses. This review aims to provide a general framework for the structure and characteristics of Slp and the interactions between Slp and liposomes, to highlight the unique properties and drug delivery as well as the biomedical applications of the Slp-coated liposomes, and to discuss the ongoing challenges and perspectives.
Collapse
Affiliation(s)
- Gan Luo
- Department of Pharmaceutics, College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou, Zhejiang, China,
- Department of Anesthesiology and Intensive Care, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Qingliang Yang
- Department of Pharmaceutics, College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou, Zhejiang, China,
| | - Bingpeng Yao
- Department of Pharmaceutics, College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou, Zhejiang, China,
- Department of Green Pharmaceutics, Jianxing Honors College, Zhejiang University of Technology, Hangzhou, Zhejiang, China
| | - Yangfan Tian
- Department of Pediatric Surgery, The Children's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Ruixia Hou
- Department of Pharmaceutics, College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou, Zhejiang, China,
| | - Anna Shao
- Department of Pharmaceutics, College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou, Zhejiang, China,
| | - Mengting Li
- Department of Pharmaceutics, College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou, Zhejiang, China,
| | - Zilin Feng
- Department of Pharmaceutics, College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou, Zhejiang, China,
| | - Wenxi Wang
- Department of Pharmaceutics, College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou, Zhejiang, China,
| |
Collapse
|
12
|
Falke S, Dierks K, Blanchet C, Graewert M, Cipriani F, Meijers R, Svergun D, Betzel C. Multi-channel in situ dynamic light scattering instrumentation enhancing biological small-angle X-ray scattering experiments at the PETRA III beamline P12. JOURNAL OF SYNCHROTRON RADIATION 2018; 25:361-372. [PMID: 29488914 DOI: 10.1107/s1600577517017568] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2017] [Accepted: 12/07/2017] [Indexed: 06/08/2023]
Abstract
Small-angle X-ray scattering (SAXS) analysis of biomolecules is increasingly common with a constantly high demand for comprehensive and efficient sample quality control prior to SAXS experiments. As monodisperse sample suspensions are desirable for SAXS experiments, latest dynamic light scattering (DLS) techniques are most suited to obtain non-invasive and rapid information about the particle size distribution of molecules in solution. A multi-receiver four-channel DLS system was designed and adapted at the BioSAXS endstation of the EMBL beamline P12 at PETRA III (DESY, Hamburg, Germany). The system allows the collection of DLS data within round-shaped sample capillaries used at beamline P12. Data obtained provide information about the hydrodynamic radius of biological particles in solution and dispersity of the solution. DLS data can be collected directly prior to and during an X-ray exposure. To match the short X-ray exposure times of around 1 s for 20 exposures at P12, the DLS data collection periods that have been used up to now of 20 s or commonly more were substantially reduced, using a novel multi-channel approach collecting DLS data sets in the SAXS sample capillary at four different neighbouring sample volume positions in parallel. The setup allows online scoring of sample solutions applied for SAXS experiments, supports SAXS data evaluation and for example indicates local inhomogeneities in a sample solution in a time-efficient manner. Biological macromolecules with different molecular weights were applied to test the system and obtain information about the performance. All measured hydrodynamic radii are in good agreement with DLS results obtained by employing a standard cuvette instrument. Moreover, applying the new multi-channel DLS setup, a reliable radius determination of sample solutions in flow, at flow rates normally used for size-exclusion chromatography-SAXS experiments, and at higher flow rates, was verified as well. This study also shows and confirms that the newly designed sample compartment with attached DLS instrumentation does not disturb SAXS measurements.
Collapse
Affiliation(s)
- Sven Falke
- Laboratory for Structural Biology of Infection and Inflammation, University Hamburg, c/o DESY, Building 22a, Notkestrasse 85, Hamburg 22603, Germany
| | - Karsten Dierks
- Xtal Concepts GmbH, Marlowring 19, Hamburg 22525, Germany
| | - Clement Blanchet
- European Molecular Biology Laboratory (EMBL), Hamburg Outstation, c/o Notkestrasse 85, Hamburg 22607, Germany
| | - Melissa Graewert
- European Molecular Biology Laboratory (EMBL), Hamburg Outstation, c/o Notkestrasse 85, Hamburg 22607, Germany
| | - Florent Cipriani
- European Molecular Biology Laboratory (EMBL), 71 Avenue des Martyrs, Grenoble 38042, France
| | - Rob Meijers
- European Molecular Biology Laboratory (EMBL), Hamburg Outstation, c/o Notkestrasse 85, Hamburg 22607, Germany
| | - Dmitri Svergun
- European Molecular Biology Laboratory (EMBL), Hamburg Outstation, c/o Notkestrasse 85, Hamburg 22607, Germany
| | - Christian Betzel
- Laboratory for Structural Biology of Infection and Inflammation, University Hamburg, c/o DESY, Building 22a, Notkestrasse 85, Hamburg 22603, Germany
| |
Collapse
|
13
|
In Vitro Characterization of the Two-Stage Non-Classical Reassembly Pathway of S-Layers. Int J Mol Sci 2017; 18:ijms18020400. [PMID: 28216572 PMCID: PMC5343934 DOI: 10.3390/ijms18020400] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2016] [Revised: 01/17/2017] [Accepted: 01/31/2017] [Indexed: 01/07/2023] Open
Abstract
The recombinant bacterial surface layer (S-layer) protein rSbpA of Lysinibacillus sphaericus CCM 2177 is an ideal model system to study non-classical nucleation and growth of protein crystals at surfaces since the recrystallization process may be separated into two distinct steps: (i) adsorption of S-layer protein monomers on silicon surfaces is completed within 5 min and the amount of bound S-layer protein sufficient for the subsequent formation of a closed crystalline monolayer; (ii) the recrystallization process is triggered—after washing away the unbound S-layer protein—by the addition of a CaCl2 containing buffer solution, and completed after approximately 2 h. The entire self-assembly process including the formation of amorphous clusters, the subsequent transformation into crystalline monomolecular arrays, and finally crystal growth into extended lattices was investigated by quartz crystal microbalance with dissipation (QCM-D) and atomic force microscopy (AFM). Moreover, contact angle measurements showed that the surface properties of S-layers change from hydrophilic to hydrophobic as the crystallization proceeds. This two-step approach is new in basic and application driven S-layer research and, most likely, will have advantages for functionalizing surfaces (e.g., by spray-coating) with tailor-made biological sensing layers.
Collapse
|
14
|
Characteristics of surface layer proteins from two new and native strains of Lactobacillus brevis. Int J Biol Macromol 2016; 95:1004-1010. [PMID: 27984145 DOI: 10.1016/j.ijbiomac.2016.10.089] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2016] [Revised: 09/06/2016] [Accepted: 10/26/2016] [Indexed: 11/22/2022]
Abstract
In this work, some important characteristics of surface layer (S-layer) proteins extracted from two new and native Lactobacillus strains, L.brevis KM3 and L.brevis KM7, were investigated. The presence of S-layer on the external surface of L.brevis KM3 was displayed by thin sectioning and negative staining. SDS-PAGE analysis were shown same dominant protein bands approximately around 48kDa for both S-layer proteins. Moreover, the S-layer reappeared when LiCl treated cells were allowed to grow again. Protein secondary structure and thermal behavior were evaluated by using circular dichroism (CD) and differential scanning calorimetry (DSC), respectively. Both S-layer proteins had high content of β-sheet and low amount of α-helix. The thermograms of lyophilized S-layer proteins of L.brevis KM3 and L.brevis KM7 showed one transition peak at 67.9°C and 59.14°C, respectively. To determine monodispersity of extracted S-layer proteins, dynamic light scattering (DLS) was used. The results indicated that the main population of S-layer molecules in two tested lactobacillus strains were composed of monomer with an expected diameter close to 10nm. Furthermore, Zeta potential measurements were showed positive potential for both S-layer proteins, as expected. Our results could be used as the basis for biotechnological applications of these two new S-layer proteins.
Collapse
|