1
|
Azad MA, Patel R. Practical Guidance for Clinical Microbiology Laboratories: Microbiologic diagnosis of implant-associated infections. Clin Microbiol Rev 2024; 37:e0010423. [PMID: 38506553 DOI: 10.1128/cmr.00104-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/21/2024] Open
Abstract
SUMMARYImplant-associated infections (IAIs) pose serious threats to patients and can be associated with significant morbidity and mortality. These infections may be difficult to diagnose due, in part, to biofilm formation on device surfaces, and because even when microbes are found, their clinical significance may be unclear. Despite recent advances in laboratory testing, IAIs remain a diagnostic challenge. From a therapeutic standpoint, many IAIs currently require device removal and prolonged courses of antimicrobial therapy to effect a cure. Therefore, making an accurate diagnosis, defining both the presence of infection and the involved microorganisms, is paramount. The sensitivity of standard microbial culture for IAI diagnosis varies depending on the type of IAI, the specimen analyzed, and the culture technique(s) used. Although IAI-specific culture-based diagnostics have been described, the challenge of culture-negative IAIs remains. Given this, molecular assays, including both nucleic acid amplification tests and next-generation sequencing-based assays, have been used. In this review, an overview of these challenging infections is presented, as well as an approach to their diagnosis from a microbiologic perspective.
Collapse
Affiliation(s)
- Marisa Ann Azad
- Division of Infectious Diseases, Department of Medicine, The Ottawa Hospital, Ottawa, Canada
- Ottawa Hospital Research Institute, Ottawa, Canada
| | - Robin Patel
- Division of Public Health, Infectious Diseases, and Occupational Medicine, Department of Medicine, Mayo Clinic, Rochester, Minnesota, USA
- Division of Clinical Microbiology, Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota, USA
| |
Collapse
|
2
|
Flemming HC, van Hullebusch ED, Neu TR, Nielsen PH, Seviour T, Stoodley P, Wingender J, Wuertz S. The biofilm matrix: multitasking in a shared space. Nat Rev Microbiol 2023; 21:70-86. [PMID: 36127518 DOI: 10.1038/s41579-022-00791-0] [Citation(s) in RCA: 135] [Impact Index Per Article: 135.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/04/2022] [Indexed: 01/20/2023]
Abstract
The biofilm matrix can be considered to be a shared space for the encased microbial cells, comprising a wide variety of extracellular polymeric substances (EPS), such as polysaccharides, proteins, amyloids, lipids and extracellular DNA (eDNA), as well as membrane vesicles and humic-like microbially derived refractory substances. EPS are dynamic in space and time and their components interact in complex ways, fulfilling various functions: to stabilize the matrix, acquire nutrients, retain and protect eDNA or exoenzymes, or offer sorption sites for ions and hydrophobic substances. The retention of exoenzymes effectively renders the biofilm matrix an external digestion system influencing the global turnover of biopolymers, considering the ubiquitous relevance of biofilms. Physico-chemical and biological interactions and environmental conditions enable biofilm systems to morph into films, microcolonies and macrocolonies, films, ridges, ripples, columns, pellicles, bubbles, mushrooms and suspended aggregates - in response to the very diverse conditions confronting a particular biofilm community. Assembly and dynamics of the matrix are mostly coordinated by secondary messengers, signalling molecules or small RNAs, in both medically relevant and environmental biofilms. Fully deciphering how bacteria provide structure to the matrix, and thus facilitate and benefit from extracellular reactions, remains the challenge for future biofilm research.
Collapse
Affiliation(s)
- Hans-Curt Flemming
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, Singapore, Singapore.
| | | | - Thomas R Neu
- Department of River Ecology, Helmholtz Centre for Environmental Research - UFZ, Magdeburg, Germany
| | - Per H Nielsen
- Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg University, Aalborg, Denmark
| | - Thomas Seviour
- Aarhus University Centre for Water Technology, Department of Biological and Chemical Engineering, Aarhus University, Aarhus, Denmark
| | - Paul Stoodley
- Department of Microbial Infection and Immunity, The Ohio State University, Columbus, OH, USA.,Department of Orthopaedics, The Ohio State University, Columbus, OH, USA
| | - Jost Wingender
- University of Duisburg-Essen, Biofilm Centre, Department of Aquatic Microbiology, Essen, Germany
| | - Stefan Wuertz
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, Singapore, Singapore
| |
Collapse
|
3
|
Caldara M, Belgiovine C, Secchi E, Rusconi R. Environmental, Microbiological, and Immunological Features of Bacterial Biofilms Associated with Implanted Medical Devices. Clin Microbiol Rev 2022; 35:e0022120. [PMID: 35044203 PMCID: PMC8768833 DOI: 10.1128/cmr.00221-20] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
The spread of biofilms on medical implants represents one of the principal triggers of persistent and chronic infections in clinical settings, and it has been the subject of many studies in the past few years, with most of them focused on prosthetic joint infections. We review here recent works on biofilm formation and microbial colonization on a large variety of indwelling devices, ranging from heart valves and pacemakers to urological and breast implants and from biliary stents and endoscopic tubes to contact lenses and neurosurgical implants. We focus on bacterial abundance and distribution across different devices and body sites and on the role of environmental features, such as the presence of fluid flow and properties of the implant surface, as well as on the interplay between bacterial colonization and the response of the human immune system.
Collapse
Affiliation(s)
- Marina Caldara
- Interdepartmental Center on Safety, Technologies, and Agri-food Innovation (SITEIA.PARMA), University of Parma, Parma, Italy
| | - Cristina Belgiovine
- IRCCS Humanitas Research Hospital, Rozzano–Milan, Italy
- Scuola di Specializzazione in Microbiologia e Virologia, Università degli Studi di Pavia, Pavia, Italy
| | - Eleonora Secchi
- Institute of Environmental Engineering, ETH Zürich, Zürich, Switzerland
| | - Roberto Rusconi
- IRCCS Humanitas Research Hospital, Rozzano–Milan, Italy
- Department of Biomedical Sciences, Humanitas University, Pieve Emanuele–Milan, Italy
| |
Collapse
|
4
|
Biofilm through the Looking Glass: A Microbial Food Safety Perspective. Pathogens 2022; 11:pathogens11030346. [PMID: 35335670 PMCID: PMC8954374 DOI: 10.3390/pathogens11030346] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Revised: 03/08/2022] [Accepted: 03/10/2022] [Indexed: 02/06/2023] Open
Abstract
Food-processing facilities harbor a wide diversity of microorganisms that persist and interact in multispecies biofilms, which could provide an ecological niche for pathogens to better colonize and gain tolerance against sanitization. Biofilm formation by foodborne pathogens is a serious threat to food safety and public health. Biofilms are formed in an environment through synergistic interactions within the microbial community through mutual adaptive response to their long-term coexistence. Mixed-species biofilms are more tolerant to sanitizers than single-species biofilms or their planktonic equivalents. Hence, there is a need to explore how multispecies biofilms help in protecting the foodborne pathogen from common sanitizers and disseminate biofilm cells from hotspots and contaminate food products. This knowledge will help in designing microbial interventions to mitigate foodborne pathogens in the processing environment. As the global need for safe, high-quality, and nutritious food increases, it is vital to study foodborne pathogen behavior and engineer new interventions that safeguard food from contamination with pathogens. This review focuses on the potential food safety issues associated with biofilms in the food-processing environment.
Collapse
|
5
|
Barraud N, Létoffé S, Beloin C, Vinh J, Chiappetta G, Ghigo JM. Lifestyle-specific S-nitrosylation of protein cysteine thiols regulates Escherichia coli biofilm formation and resistance to oxidative stress. NPJ Biofilms Microbiomes 2021; 7:34. [PMID: 33850153 PMCID: PMC8044216 DOI: 10.1038/s41522-021-00203-w] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Accepted: 02/18/2021] [Indexed: 02/03/2023] Open
Abstract
Communities of bacteria called biofilms are characterized by reduced diffusion, steep oxygen, and redox gradients and specific properties compared to individualized planktonic bacteria. In this study, we investigated whether signaling via nitrosylation of protein cysteine thiols (S-nitrosylation), regulating a wide range of functions in eukaryotes, could also specifically occur in biofilms and contribute to bacterial adaptation to this widespread lifestyle. We used a redox proteomic approach to compare cysteine S-nitrosylation in aerobic and anaerobic biofilm and planktonic Escherichia coli cultures and we identified proteins with biofilm-specific S-nitrosylation status. Using bacterial genetics and various phenotypic screens, we showed that impairing S-nitrosylation in proteins involved in redox homeostasis and amino acid synthesis such as OxyR, KatG, and GltD altered important biofilm properties, including motility, biofilm maturation, or resistance to oxidative stress. Our study therefore revealed that S-nitrosylation constitutes a physiological basis underlying functions critical for E. coli adaptation to the biofilm environment.
Collapse
Affiliation(s)
- Nicolas Barraud
- Genetics of Biofilms Laboratory, Institut Pasteur, UMR CNRS2001, Paris, France
| | - Sylvie Létoffé
- Genetics of Biofilms Laboratory, Institut Pasteur, UMR CNRS2001, Paris, France
| | - Christophe Beloin
- Genetics of Biofilms Laboratory, Institut Pasteur, UMR CNRS2001, Paris, France
| | - Joelle Vinh
- Biological Mass Spectrometry and Proteomics (SMBP), ESPCI Paris, Université PSL, CNRS FRE2032, 75005, Paris, France
| | - Giovanni Chiappetta
- Biological Mass Spectrometry and Proteomics (SMBP), ESPCI Paris, Université PSL, CNRS FRE2032, 75005, Paris, France.
| | - Jean-Marc Ghigo
- Genetics of Biofilms Laboratory, Institut Pasteur, UMR CNRS2001, Paris, France.
| |
Collapse
|
6
|
Hallinen KM, Guardiola-Flores KA, Wood KB. Fluorescent reporter plasmids for single-cell and bulk-level composition assays in E. faecalis. PLoS One 2020; 15:e0232539. [PMID: 32369497 PMCID: PMC7199960 DOI: 10.1371/journal.pone.0232539] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Accepted: 04/16/2020] [Indexed: 01/04/2023] Open
Abstract
Fluorescent reporters are an important tool for monitoring dynamics of bacterial populations at the single cell and community level. While there are a large range of reporter constructs available–particularly for common model organisms like E. coli–fewer options exist for other species, including E. faecalis, a gram-positive opportunistic pathogen. To expand the potential toolkit available for E. faecalis, we exchanged the original fluorescent reporter in a previously developed plasmid (pBSU101) with one of eight fluorescent reporters and confirmed that all constructs exhibited detectable fluorescence in single E. faecalis cells and mixed biofilm communities. To identify promising constructs for bulk-level experiments, we then measured the fluorescence spectra from E. faecalis populations in microwell plate (liquid) cultures during different phases of aerobic growth. Cultures showed density- and reporter-specific variations in fluorescent signal, though spectral signatures of all reporters become clear in late-exponential and stationary-phase populations. Based on these results, we identified six pairs of reporters that can be combined with simple spectral unmixing to accurately estimate population composition in 2-strain mixtures at or near stationary phase. This approach offers a simple and scalable method for selection and competition experiments in simple two-species populations under aerobic growth conditions. Finally, we incorporated codon-optimized variants of blue (BFP) and red (RFP) reporters and show that they lead to increased fluorescence in exponentially growing cells. As a whole, the results inform the scope of application of different reporters and identify both single reporters and reporter pairs that are promising for fluorescence-based assays at bulk and single-cell levels in E. faecalis.
Collapse
Affiliation(s)
- Kelsey M. Hallinen
- Department of Biophysics, University of Michigan, Ann Arbor, Michigan, United States of America
| | | | - Kevin B. Wood
- Department of Biophysics, University of Michigan, Ann Arbor, Michigan, United States of America
- Department of Physics, University of Michigan, Ann Arbor, Michigan, United States of America
- * E-mail:
| |
Collapse
|
7
|
Bueno E, Pinedo V, Cava F. Adaptation of Vibrio cholerae to Hypoxic Environments. Front Microbiol 2020; 11:739. [PMID: 32425907 PMCID: PMC7212424 DOI: 10.3389/fmicb.2020.00739] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Accepted: 03/30/2020] [Indexed: 01/02/2023] Open
Abstract
Bacteria can colonize virtually any environment on Earth due to their remarkable capacity to detect and respond quickly and adequately to environmental stressors. Vibrio cholerae is a cosmopolitan bacterium that inhabits a vast range of environments. The V. cholerae life cycle comprises diverse environmental and infective stages. The bacterium is found in aquatic ecosystems both under free-living conditions or associated with a wide range of aquatic organisms, and some strains are also capable of causing epidemics in humans. In order to adapt between environments, V. cholerae possesses a versatile metabolism characterized by the rapid cross-regulation of energy-producing pathways. Low oxygen concentration is a key environmental factor that governs V. cholerae physiology. This article reviews the metabolic plasticity that enables V. cholerae to thrive on low oxygen concentrations and its role in environmental and host adaptation.
Collapse
Affiliation(s)
- Emilio Bueno
- Laboratory for Molecular Infection Medicine Sweden, Department of Molecular Biology, Umeå Centre for Microbial Research, Umeå University, Umeå, Sweden
| | | | - Felipe Cava
- Laboratory for Molecular Infection Medicine Sweden, Department of Molecular Biology, Umeå Centre for Microbial Research, Umeå University, Umeå, Sweden
| |
Collapse
|
8
|
Sankaran J, Tan NJHJ, But KP, Cohen Y, Rice SA, Wohland T. Single microcolony diffusion analysis in Pseudomonas aeruginosa biofilms. NPJ Biofilms Microbiomes 2019; 5:35. [PMID: 31728202 PMCID: PMC6841743 DOI: 10.1038/s41522-019-0107-4] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Accepted: 10/04/2019] [Indexed: 01/25/2023] Open
Abstract
The influence of the biofilm matrix on molecular diffusion is commonly hypothesized to be responsible for emergent characteristics of biofilms such as nutrient trapping, signal accumulation and antibiotic tolerance. Hence quantifying the molecular diffusion coefficient is important to determine whether there is an influence of biofilm microenvironment on the mobility of molecules. Here, we use single plane illumination microscopy fluorescence correlation spectroscopy (SPIM-FCS) to obtain 3D diffusion coefficient maps with micrometre spatial and millisecond temporal resolution of entire Pseudomonas aeruginosa microcolonies. We probed how molecular properties such as size and charge as well as biofilm properties such as microcolony size and depth influence diffusion of fluorescently labelled dextrans inside biofilms. The 2 MDa dextran showed uneven penetration and a reduction in diffusion coefficient suggesting that the biofilm acts as a molecular sieve. Its diffusion coefficient was negatively correlated with the size of the microcolony. Positively charged dextran molecules and positively charged antibiotic tobramycin preferentially partitioned into the biofilm and remained mobile inside the microcolony, albeit with a reduced diffusion coefficient. Lastly, we measured changes of diffusion upon induction of dispersal and detected an increase in diffusion coefficient inside the biofilm before any loss of biomass. Thus, the change in diffusion is a proxy to detect early stages of dispersal. Our work shows that 3D diffusion maps are very sensitive to physiological changes in biofilms, viz. dispersal. However, this study also shows that diffusion, as mediated by the biofilm matrix, does not account for the high level of antibiotic tolerance associated with biofilms.
Collapse
Affiliation(s)
- Jagadish Sankaran
- 1Department of Biological Sciences, National University of Singapore, 117558 Singapore, Singapore.,2Centre for BioImaging Sciences, National University of Singapore, 117557 Singapore, Singapore
| | - Nicholas J H J Tan
- 3Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, 637551 Singapore, Singapore.,4School of Biological Sciences, Nanyang Technological University, 637551 Singapore, Singapore
| | - Ka Pui But
- 2Centre for BioImaging Sciences, National University of Singapore, 117557 Singapore, Singapore.,5Department of Chemistry, National University of Singapore, 117543 Singapore, Singapore
| | - Yehuda Cohen
- 3Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, 637551 Singapore, Singapore.,4School of Biological Sciences, Nanyang Technological University, 637551 Singapore, Singapore
| | - Scott A Rice
- 3Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, 637551 Singapore, Singapore.,4School of Biological Sciences, Nanyang Technological University, 637551 Singapore, Singapore.,6ithree Institute, University of Technology Sydney, Sydney, Australia
| | - Thorsten Wohland
- 1Department of Biological Sciences, National University of Singapore, 117558 Singapore, Singapore.,2Centre for BioImaging Sciences, National University of Singapore, 117557 Singapore, Singapore.,5Department of Chemistry, National University of Singapore, 117543 Singapore, Singapore
| |
Collapse
|
9
|
Sankaran J, Karampatzakis A, Rice SA, Wohland T. Quantitative imaging and spectroscopic technologies for microbiology. FEMS Microbiol Lett 2019; 365:4953418. [PMID: 29718275 DOI: 10.1093/femsle/fny075] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Accepted: 03/23/2018] [Indexed: 12/17/2022] Open
Abstract
Light microscopy has enabled the observation of the structure and organisation of biofilms. Typically, the contrast in an image obtained from light microscopy is given by the time-averaged intensity that is effective in visualising the overall structure. Technological advancements in light microscopy have led to the creation of techniques that not only provide a static intensity image of the biofilm, but also enable one to quantify various dynamic physicochemical properties of biomolecules in microbial biofilms. Such light microscopy-based techniques can be grouped into two main classes, those that are based on luminescence and those that are based on scattering. Here, we review the fundamentals and applications of luminescence and scattering-based techniques, specifically, fluorescence lifetime imaging, Förster resonance energy transfer, fluorescence correlation spectroscopy, fluorescence recovery after photobleaching, single-particle tracking, transient state imaging, and Brillouin and Raman microscopy. These techniques provide information about the abundance, interactions and mobility of various molecules in the biofilms and also properties of the local microenvironment at optical resolution. Further, one could use any of these techniques to probe the real-time changes in these physical parameters upon the addition of external agents or at different stages during the growth of biofilms.
Collapse
Affiliation(s)
- Jagadish Sankaran
- Departments of Biological Sciences and Chemistry, National University of Singapore, Singapore 117558, Singapore.,Centre for BioImaging Sciences, National University of Singapore, Singapore 117557, Singapore
| | - Andreas Karampatzakis
- Centre for BioImaging Sciences, National University of Singapore, Singapore 117557, Singapore.,NUS Graduate School for Integrative Sciences and Engineering, National University of Singapore, Singapore 117456, Singapore
| | - Scott A Rice
- Singapore Centre for Environmental Life Sciences Engineering and School of Biological Sciences, Nanyang Technological University, Singapore 637551, Singapore.,ithree Institute, University of Technology, Sydney 2007, Australia
| | - Thorsten Wohland
- Departments of Biological Sciences and Chemistry, National University of Singapore, Singapore 117558, Singapore.,Centre for BioImaging Sciences, National University of Singapore, Singapore 117557, Singapore.,NUS Graduate School for Integrative Sciences and Engineering, National University of Singapore, Singapore 117456, Singapore
| |
Collapse
|
10
|
Parthasarathy R. Monitoring microbial communities using light sheet fluorescence microscopy. Curr Opin Microbiol 2018; 43:31-37. [PMID: 29175679 PMCID: PMC5963963 DOI: 10.1016/j.mib.2017.11.008] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2017] [Revised: 10/10/2017] [Accepted: 11/06/2017] [Indexed: 01/20/2023]
Abstract
Microbes often live in dense, dynamic, multi-species communities whose architecture and function are intimately intertwined. Imaging these complex, three-dimensional ensembles presents considerable technical challenges, however. In this review, I describe light sheet fluorescence microscopy, a technique that enables rapid acquisition of three-dimensional images over large fields of view and over long durations, and I highlight recent applications of this method to microbial systems that include artificial closed ecosystems, bacterial biofilms, and gut microbiota. I comment also on the history of light sheet imaging and the many variants of the method. Light sheet techniques have tremendous potential for illuminating the workings of microbial communities, a potential that is just beginning to be realized.
Collapse
|
11
|
Tornmalm J, Widengren J. Label-free monitoring of ambient oxygenation and redox conditions using the photodynamics of flavin compounds and transient state (TRAST) spectroscopy. Methods 2017; 140-141:178-187. [PMID: 29179988 DOI: 10.1016/j.ymeth.2017.11.013] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2017] [Accepted: 11/21/2017] [Indexed: 10/18/2022] Open
Abstract
Transient state (TRAST) monitoring can determine population dynamics of long-lived, dark transient states of fluorescent molecules, detecting only the average fluorescence intensity from a sample, when subject to different excitation pulse trains. Like Fluorescence Correlation Spectroscopy (FCS), TRAST unites the detection sensitivity of fluorescence with the environmental sensitivity of long-lived non-fluorescent states, but does not rely on detection of stochastic fluorescence fluctuations from individual molecules. Relaxed requirements on noise suppression, detection quantum yield and time-resolution of the instrument, as well as on fluorescence brightness of the molecules studied, make TRAST broadly applicable, opening also for investigations based on less bright, auto-fluorescent molecules. In this work, we applied TRAST to study the transient state population dynamics within the auto-fluorescent coenzymes flavin adenine dinucleotide (FAD) and flavin-mononucleotide (FMN). From the experimental TRAST data, we defined state models, and determined rate parameters for triplet state and redox transitions within FMN and FAD, stacking and un-stacking rates of external redox active quenching agents and by the adenine moiety of FAD itself. TRAST experiments were found to be well capable to resolve these transitions in FMN and FAD, and to track how the transitions are influenced by ambient oxygenation and redox conditions. This work demonstrates that TRAST provides a useful tool to follow local oxygenation and redox conditions via FMN and FAD fluorescence, and forms the basis for measurements on flavo-proteins and of redox and metabolic conditions in more complex environments, such as in live cells.
Collapse
Affiliation(s)
- Johan Tornmalm
- Experimental Biomolecular Physics, Department of Applied Physics, Royal Institute of Technology (KTH), Albanova University Center, 106 91 Stockholm, Sweden.
| | - Jerker Widengren
- Experimental Biomolecular Physics, Department of Applied Physics, Royal Institute of Technology (KTH), Albanova University Center, 106 91 Stockholm, Sweden.
| |
Collapse
|