1
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Bousbaine D, Bauman KD, Chen YE, Lalgudi PV, Nguyen TTD, Swenson JM, Yu VK, Tsang E, Conlan S, Li DB, Jbara A, Zhao A, Naziripour A, Veinbachs A, Lee YE, Phung JL, Dimas A, Jain S, Meng X, Pham TPT, McLaughlin MI, Barkal LJ, Gribonika I, Van Rompay KKA, Kong HH, Segre JA, Belkaid Y, Barnes CO, Fischbach MA. Discovery and engineering of the antibody response to a prominent skin commensal. Nature 2025; 638:1054-1064. [PMID: 39662508 PMCID: PMC12045117 DOI: 10.1038/s41586-024-08489-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Accepted: 12/04/2024] [Indexed: 12/13/2024]
Abstract
The ubiquitous skin colonist Staphylococcus epidermidis elicits a CD8+ T cell response pre-emptively, in the absence of an infection1. However, the scope and purpose of this anticommensal immune programme are not well defined, limiting our ability to harness it therapeutically. Here, we show that this colonist also induces a potent, durable and specific antibody response that is conserved in humans and non-human primates. A series of S. epidermidis cell-wall mutants revealed that the cell surface protein Aap is a predominant target. By colonizing mice with a strain of S. epidermidis in which the parallel β-helix domain of Aap is replaced by tetanus toxin fragment C, we elicit a potent neutralizing antibody response that protects mice against a lethal challenge. A similar strain of S. epidermidis expressing an Aap-SpyCatcher chimera can be conjugated with recombinant immunogens; the resulting labelled commensal elicits high antibody titres under conditions of physiologic colonization, including a robust IgA response in the nasal and pulmonary mucosa. Thus, immunity to a common skin colonist involves a coordinated T and B cell response, the latter of which can be redirected against pathogens as a new form of topical vaccination.
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Affiliation(s)
- Djenet Bousbaine
- Department of Bioengineering, Stanford University, Stanford, CA, USA
- ChEM-H Institute, Stanford University, Stanford, CA, USA
| | - Katherine D Bauman
- Department of Bioengineering, Stanford University, Stanford, CA, USA
- ChEM-H Institute, Stanford University, Stanford, CA, USA
| | - Y Erin Chen
- Department of Bioengineering, Stanford University, Stanford, CA, USA
- ChEM-H Institute, Stanford University, Stanford, CA, USA
| | - Pranav V Lalgudi
- ChEM-H Institute, Stanford University, Stanford, CA, USA
- Department of Genetics, Stanford University School of Medicine, Stanford, CA, USA
| | - Tam T D Nguyen
- Department of Bioengineering, Stanford University, Stanford, CA, USA
- ChEM-H Institute, Stanford University, Stanford, CA, USA
| | - Joyce M Swenson
- Department of Bioengineering, Stanford University, Stanford, CA, USA
- ChEM-H Institute, Stanford University, Stanford, CA, USA
| | - Victor K Yu
- Department of Bioengineering, Stanford University, Stanford, CA, USA
- ChEM-H Institute, Stanford University, Stanford, CA, USA
| | - Eunice Tsang
- Department of Bioengineering, Stanford University, Stanford, CA, USA
- ChEM-H Institute, Stanford University, Stanford, CA, USA
| | - Sean Conlan
- Microbial Genomics Section, Translational and Functional Genomics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA
| | - David B Li
- Department of Bioengineering, Stanford University, Stanford, CA, USA
- ChEM-H Institute, Stanford University, Stanford, CA, USA
| | - Amina Jbara
- Department of Bioengineering, Stanford University, Stanford, CA, USA
- ChEM-H Institute, Stanford University, Stanford, CA, USA
| | - Aishan Zhao
- Department of Bioengineering, Stanford University, Stanford, CA, USA
- ChEM-H Institute, Stanford University, Stanford, CA, USA
| | - Arash Naziripour
- Department of Bioengineering, Stanford University, Stanford, CA, USA
- ChEM-H Institute, Stanford University, Stanford, CA, USA
| | - Alessandra Veinbachs
- Department of Bioengineering, Stanford University, Stanford, CA, USA
- ChEM-H Institute, Stanford University, Stanford, CA, USA
| | - Yu E Lee
- ChEM-H Institute, Stanford University, Stanford, CA, USA
- Department of Biology, Stanford University, Stanford, CA, USA
| | - Jennie L Phung
- ChEM-H Institute, Stanford University, Stanford, CA, USA
- Department of Biology, Stanford University, Stanford, CA, USA
| | - Alex Dimas
- Department of Bioengineering, Stanford University, Stanford, CA, USA
- ChEM-H Institute, Stanford University, Stanford, CA, USA
| | - Sunit Jain
- Chan Zuckerberg Biohub, Stanford, CA, USA
| | - Xiandong Meng
- ChEM-H Institute, Stanford University, Stanford, CA, USA
| | - Thi Phuong Thao Pham
- Department of Bioengineering, Stanford University, Stanford, CA, USA
- ChEM-H Institute, Stanford University, Stanford, CA, USA
| | - Martin I McLaughlin
- Department of Bioengineering, Stanford University, Stanford, CA, USA
- ChEM-H Institute, Stanford University, Stanford, CA, USA
| | - Layla J Barkal
- Department of Bioengineering, Stanford University, Stanford, CA, USA
- ChEM-H Institute, Stanford University, Stanford, CA, USA
- Division of Pulmonary, Allergy, and Critical Care Medicine, Stanford University School of Medicine, Stanford, CA, USA
| | - Inta Gribonika
- Metaorganism Immunity Section, Laboratory of Host Immunity and Microbiome, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
- NIAID Microbiome Program, National Institute of Allergy and Infectious Diseases, Bethesda, MD, USA
| | - Koen K A Van Rompay
- California National Primate Research Center, University of California, Davis, CA, USA
- Department of Pathology, Microbiology, and Immunology, University of California, Davis, CA, USA
| | - Heidi H Kong
- Dermatology Branch, National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Julia A Segre
- Microbial Genomics Section, Translational and Functional Genomics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA
| | - Yasmine Belkaid
- Metaorganism Immunity Section, Laboratory of Host Immunity and Microbiome, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
- NIAID Microbiome Program, National Institute of Allergy and Infectious Diseases, Bethesda, MD, USA
| | - Christopher O Barnes
- ChEM-H Institute, Stanford University, Stanford, CA, USA
- Department of Biology, Stanford University, Stanford, CA, USA
- Chan Zuckerberg Biohub, Stanford, CA, USA
| | - Michael A Fischbach
- Department of Bioengineering, Stanford University, Stanford, CA, USA.
- ChEM-H Institute, Stanford University, Stanford, CA, USA.
- Chan Zuckerberg Biohub, Stanford, CA, USA.
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2
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Yarawsky AE, Herr AB. Assembly landscape of the complete B-repeat superdomain from Staphylococcus epidermidis strain 1457. Biophys J 2025; 124:363-378. [PMID: 39668565 PMCID: PMC11788477 DOI: 10.1016/j.bpj.2024.12.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2024] [Revised: 11/15/2024] [Accepted: 12/09/2024] [Indexed: 12/14/2024] Open
Abstract
The accumulation-associated protein (Aap) is the primary determinant of Staphylococcus epidermidis device-related infections. The B-repeat superdomain is responsible for intercellular adhesion that leads to the development of biofilms occurring in such infections. It was recently demonstrated that Zn-induced B-repeat assembly leads to formation of functional amyloid fibrils, which offer strength and stability to the biofilm. Rigorous biophysical studies of Aap B-repeats from S. epidermidis strain RP62A revealed Zn-induced assembly into stable, reversible dimers and tetramers, prior to aggregation into amyloid fibrils. Genetic manipulation is not tractable for many S. epidermidis strains, including RP62A; instead, many genetic studies have used strain 1457. Therefore, to better connect findings from biophysical and structural studies of B-repeats to in vivo studies, the B-repeat superdomain from strain 1457 was examined. Differences between the B-repeats from strains RP62A and 1457 include the number of B-repeats, which has been shown to play a critical role in assembly into amyloid fibrils, as well as the distribution of consensus and variant B-repeat subtypes, which differ in assembly competency and thermal stability. Detailed investigation of the Zn-induced assembly of the full B-repeat superdomain from strain 1457 was conducted using analytical ultracentrifugation. Whereas the previous construct from RP62A (Brpt5.5) formed a stable tetramer prior to aggregation, Brpt6.5 from 1457 forms extremely large stable species on the order of ≈28-mers, prior to aggregation into similar amyloid fibrils. Our data suggest that both assembly pathways may proceed through the same mechanism of dimerization and tetramerization, and both conclude with the formation of amyloid-like fibrils. Discussion of assembly behavior of B-repeats from different strains and of different length is provided with considerations of biological implications.
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Affiliation(s)
- Alexander E Yarawsky
- Division of Immunobiology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - Andrew B Herr
- Division of Immunobiology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio; Division of Infectious Diseases, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio; Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio.
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3
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Burke Ó, Zeden MS, O’Gara JP. The pathogenicity and virulence of the opportunistic pathogen Staphylococcus epidermidis. Virulence 2024; 15:2359483. [PMID: 38868991 PMCID: PMC11178275 DOI: 10.1080/21505594.2024.2359483] [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] [Received: 02/02/2024] [Accepted: 05/19/2024] [Indexed: 06/14/2024] Open
Abstract
The pervasive presence of Staphylococcus epidermidis and other coagulase-negative staphylococci on the skin and mucous membranes has long underpinned a casual disregard for the infection risk that these organisms pose to vulnerable patients in healthcare settings. Prior to the recognition of biofilm as an important virulence determinant in S. epidermidis, isolation of this microorganism in diagnostic specimens was often overlooked as clinically insignificant with potential delays in diagnosis and onset of appropriate treatment, contributing to the establishment of chronic infection and increased morbidity or mortality. While impressive progress has been made in our understanding of biofilm mechanisms in this important opportunistic pathogen, research into other virulence determinants has lagged S. aureus. In this review, the broader virulence potential of S. epidermidis including biofilm, toxins, proteases, immune evasion strategies and antibiotic resistance mechanisms is surveyed, together with current and future approaches for improved therapeutic interventions.
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Affiliation(s)
- Órla Burke
- Microbiology, School of Biological and Chemical Sciences, University of Galway, Galway, Ireland
| | | | - James P. O’Gara
- Microbiology, School of Biological and Chemical Sciences, University of Galway, Galway, Ireland
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Crosby HA, Keim K, Kwiecinski JM, Langouët-Astrié CJ, Oshima K, LaRivière WB, Schmidt EP, Horswill AR. Host-derived protease promotes aggregation of Staphylococcus aureus by cleaving the surface protein SasG. mBio 2024; 15:e0348323. [PMID: 38511930 PMCID: PMC11005337 DOI: 10.1128/mbio.03483-23] [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: 01/11/2024] [Accepted: 02/21/2024] [Indexed: 03/22/2024] Open
Abstract
Staphylococcus aureus is one of the leading causes of hospital-acquired infections, many of which begin following attachment and accumulation on indwelling medical devices or diseased tissue. These infections are often linked to the establishment of biofilms, but another often overlooked key characteristic allowing S. aureus to establish persistent infection is the formation of planktonic aggregates. Such aggregates are physiologically similar to biofilms and protect pathogens from innate immune clearance and increase antibiotic tolerance. The cell-wall-associated protein SasG has been implicated in biofilm formation via mechanisms of intercellular aggregation but the mechanism in the context of disease is largely unknown. We have previously shown that the expression of cell-wall-anchored proteins involved in biofilm formation is controlled by the ArlRS-MgrA regulatory cascade. In this work, we demonstrate that the ArlRS two-component system controls aggregation, by repressing the expression of sasG by activation of the global regulator MgrA. We also demonstrate that SasG must be proteolytically processed by a non-staphylococcal protease to induce aggregation and that strains expressing functional full-length sasG aggregate significantly upon proteolysis by a mucosal-derived host protease found in human saliva. We used fractionation and N-terminal sequencing to demonstrate that human trypsin within saliva cleaves within the A domain of SasG to expose the B domain and induce aggregation. Finally, we demonstrated that SasG is involved in virulence during mouse lung infection. Together, our data point to SasG, its processing by host proteases, and SasG-driven aggregation as important elements of S. aureus adaptation to the host environment.IMPORTANCEHere, we demonstrate that the Staphylococcus aureus surface protein SasG is important for cell-cell aggregation in the presence of host proteases. We show that the ArlRS two-component regulatory system controls SasG levels through the cytoplasmic regulator MgrA. We identified human trypsin as the dominant protease triggering SasG-dependent aggregation and demonstrated that SasG is important for S. aureus lung infection. The discovery that host proteases can induce S. aureus aggregation contributes to our understanding of how this pathogen establishes persistent infections. The observations in this study demonstrate the need to strengthen our knowledge of S. aureus surface adhesin function and processing, regulation of adhesin expression, and the mechanisms that promote biofilm formation to develop strategies for preventing chronic infections.
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Affiliation(s)
- Heidi A. Crosby
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, Colorado, USA
| | - Klara Keim
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, Colorado, USA
| | - Jakub M. Kwiecinski
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, Colorado, USA
- Department of Microbiology, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland
| | - Christophe J. Langouët-Astrié
- Division of Pulmonary Sciences and Critical Care Medicine, Department of Medicine, University of Colorado School of Medicine, Aurora, Colorado, USA
| | - Kaori Oshima
- Division of Pulmonary Sciences and Critical Care, Department of Medicine, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Wells B. LaRivière
- Division of Pulmonary Sciences and Critical Care Medicine, Department of Medicine, University of Colorado School of Medicine, Aurora, Colorado, USA
| | - Eric P. Schmidt
- Division of Pulmonary Sciences and Critical Care, Department of Medicine, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Alexander R. Horswill
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, Colorado, USA
- Department of Veterans Affairs Eastern Colorado Health Care System, Denver, Colorado, USA
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Song M, Tang Q, Ding Y, Tan P, Zhang Y, Wang T, Zhou C, Xu S, Lyu M, Bai Y, Ma X. Staphylococcus aureus and biofilms: transmission, threats, and promising strategies in animal husbandry. J Anim Sci Biotechnol 2024; 15:44. [PMID: 38475886 PMCID: PMC10936095 DOI: 10.1186/s40104-024-01007-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2023] [Accepted: 02/03/2024] [Indexed: 03/14/2024] Open
Abstract
Staphylococcus aureus (S. aureus) is a common pathogenic bacterium in animal husbandry that can cause diseases such as mastitis, skin infections, arthritis, and other ailments. The formation of biofilms threatens and exacerbates S. aureus infection by allowing the bacteria to adhere to pathological areas and livestock product surfaces, thus triggering animal health crises and safety issues with livestock products. To solve this problem, in this review, we provide a brief overview of the harm caused by S. aureus and its biofilms on livestock and animal byproducts (meat and dairy products). We also describe the ways in which S. aureus spreads in animals and the threats it poses to the livestock industry. The processes and molecular mechanisms involved in biofilm formation are then explained. Finally, we discuss strategies for the removal and eradication of S. aureus and biofilms in animal husbandry, including the use of antimicrobial peptides, plant extracts, nanoparticles, phages, and antibodies. These strategies to reduce the spread of S. aureus in animal husbandry help maintain livestock health and improve productivity to ensure the ecologically sustainable development of animal husbandry and the safety of livestock products.
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Affiliation(s)
- Mengda Song
- State Key Laboratory of Animal Nutrition and Feeding, College of Animal Science and Technology, China Agricultural University, Beijing, 100193, China
- Key Laboratory of Innovative Utilization of Local Cattle and Sheep Germplasm Resources (Co-Construction by Ministry and Province), Ministry of Agriculture and Rural Affairs, School of Agricultural Sciences, Zhengzhou University, Zhengzhou, 450001, China
| | - Qi Tang
- State Key Laboratory of Animal Nutrition and Feeding, College of Animal Science and Technology, China Agricultural University, Beijing, 100193, China
| | - Yakun Ding
- State Key Laboratory of Animal Nutrition and Feeding, College of Animal Science and Technology, China Agricultural University, Beijing, 100193, China
| | - Peng Tan
- State Key Laboratory of Animal Nutrition and Feeding, College of Animal Science and Technology, China Agricultural University, Beijing, 100193, China
| | - Yucheng Zhang
- State Key Laboratory of Animal Nutrition and Feeding, College of Animal Science and Technology, China Agricultural University, Beijing, 100193, China
| | - Tao Wang
- State Key Laboratory of Animal Nutrition and Feeding, College of Animal Science and Technology, China Agricultural University, Beijing, 100193, China
| | - Chenlong Zhou
- State Key Laboratory of Animal Nutrition and Feeding, College of Animal Science and Technology, China Agricultural University, Beijing, 100193, China
| | - Shenrui Xu
- State Key Laboratory of Animal Nutrition and Feeding, College of Animal Science and Technology, China Agricultural University, Beijing, 100193, China
| | - Mengwei Lyu
- State Key Laboratory of Animal Nutrition and Feeding, College of Animal Science and Technology, China Agricultural University, Beijing, 100193, China
| | - Yueyu Bai
- Key Laboratory of Innovative Utilization of Local Cattle and Sheep Germplasm Resources (Co-Construction by Ministry and Province), Ministry of Agriculture and Rural Affairs, School of Agricultural Sciences, Zhengzhou University, Zhengzhou, 450001, China.
| | - Xi Ma
- State Key Laboratory of Animal Nutrition and Feeding, College of Animal Science and Technology, China Agricultural University, Beijing, 100193, China.
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Bousbaine D, Bauman KD, Chen YE, Yu VK, Lalgudi PV, Naziripour A, Veinbachs A, Phung JL, Nguyen TTD, Swenson JM, Lee YE, Dimas A, Jain S, Meng X, Pham TPT, Zhao A, Barkal L, Gribonika I, Van Rompay KKA, Belkaid Y, Barnes CO, Fischbach MA. Discovery and engineering of the antibody response against a prominent skin commensal. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.23.576900. [PMID: 38328052 PMCID: PMC10849572 DOI: 10.1101/2024.01.23.576900] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/09/2024]
Abstract
The ubiquitous skin colonist Staphylococcus epidermidis elicits a CD8 + T cell response pre-emptively, in the absence of an infection 1 . However, the scope and purpose of this anti-commensal immune program are not well defined, limiting our ability to harness it therapeutically. Here, we show that this colonist also induces a potent, durable, and specific antibody response that is conserved in humans and non-human primates. A series of S. epidermidis cell-wall mutants revealed that the cell surface protein Aap is a predominant target. By colonizing mice with a strain of S. epidermidis in which the parallel β-helix domain of Aap is replaced by tetanus toxin fragment C, we elicit a potent neutralizing antibody response that protects mice against a lethal challenge. A similar strain of S. epidermidis expressing an Aap-SpyCatcher chimera can be conjugated with recombinant immunogens; the resulting labeled commensal elicits high titers of antibody under conditions of physiologic colonization, including a robust IgA response in the nasal mucosa. Thus, immunity to a common skin colonist involves a coordinated T and B cell response, the latter of which can be redirected against pathogens as a novel form of topical vaccination.
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7
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Campoccia D, Ravaioli S, Mirzaei R, Bua G, Daglia M, Arciola CR. Interactions of Neutrophils with the Polymeric Molecular Components of the Biofilm Matrix in the Context of Implant-Associated Bone and Joint Infections. Int J Mol Sci 2023; 24:17042. [PMID: 38069365 PMCID: PMC10707472 DOI: 10.3390/ijms242317042] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Revised: 11/29/2023] [Accepted: 11/29/2023] [Indexed: 12/18/2023] Open
Abstract
In the presence of orthopedic implants, opportunistic pathogens can easily colonize the biomaterial surfaces, forming protective biofilms. Life in biofilm is a central pathogenetic mechanism enabling bacteria to elude the host immune response and survive conventional medical treatments. The formation of mature biofilms is universally recognized as the main cause of septic prosthetic failures. Neutrophils are the first leukocytes to be recruited at the site of infection. They are highly efficient in detecting and killing planktonic bacteria. However, the interactions of these fundamental effector cells of the immune system with the biofilm matrix, which is the true interface of a biofilm with the host cells, have only recently started to be unveiled and are still to be fully understood. Biofilm matrix macromolecules consist of exopolysaccharides, proteins, lipids, teichoic acids, and the most recently described extracellular DNA. The latter can also be stolen from neutrophil extracellular traps (NETs) by bacteria, who use it to strengthen their biofilms. This paper aims to review the specific interactions that neutrophils develop when they physically encounter the matrix of a biofilm and come to interact with its polymeric molecular components.
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Affiliation(s)
- Davide Campoccia
- Laboratorio di Patologia Delle Infezioni Associate all’Impianto, IRCCS Istituto Ortopedico Rizzoli, Via di Barbiano 1/10, 40136 Bologna, Italy; (D.C.); (S.R.); (G.B.)
| | - Stefano Ravaioli
- Laboratorio di Patologia Delle Infezioni Associate all’Impianto, IRCCS Istituto Ortopedico Rizzoli, Via di Barbiano 1/10, 40136 Bologna, Italy; (D.C.); (S.R.); (G.B.)
| | - Rasoul Mirzaei
- Venom and Biotherapeutics Molecules Laboratory, Medical Biotechnology Department, Biotechnology Research Center, Pasteur Institute of Iran, Tehran 1316943551, Iran;
| | - Gloria Bua
- Laboratorio di Patologia Delle Infezioni Associate all’Impianto, IRCCS Istituto Ortopedico Rizzoli, Via di Barbiano 1/10, 40136 Bologna, Italy; (D.C.); (S.R.); (G.B.)
| | - Maria Daglia
- Department of Pharmacy, University of Napoli Federico II, Via D. Montesano 49, 80131 Naples, Italy;
- International Research Center for Food Nutrition and Safety, Jiangsu University, Zhenjiang 212013, China
| | - Carla Renata Arciola
- Laboratory of Immunorheumatology and Tissue Regeneration, Laboratory of Pathology of Implant Infections, IRCCS Istituto Ortopedico Rizzoli, Via di Barbiano 1/10, 40136 Bologna, Italy
- Department of Medical and Surgical Sciences (DIMEC), University of Bologna, Via San Giacomo 14, 40126 Bologna, Italy
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Yadav R, Shaikh T, Tikole S, Herr AB, Fitzkee NC. 1H, 15N, and 13C chemical shift backbone resonance NMR assignment of the accumulation-associated protein (Aap) lectin domain from Staphylococcus epidermidis. BIOMOLECULAR NMR ASSIGNMENTS 2023; 17:95-99. [PMID: 37022616 PMCID: PMC10247473 DOI: 10.1007/s12104-023-10126-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2023] [Accepted: 03/30/2023] [Indexed: 06/02/2023]
Abstract
Staphylococcus epidermidis is the leading causative agent for hospital-acquired infections, especially device-related infections, due to its ability to form biofilms. The accumulation-associated protein (Aap) of S. epidermidis is primarily responsible for biofilm formation and consists of two domains, A and B. It was found that the A domain is responsible for the attachment to the abiotic/biotic surface, whereas the B domain is responsible for the accumulation of bacteria during biofilm formation. One of the parts of the A domain is the Aap lectin, which is a carbohydrate-binding domain having 222 amino acids in its structure. Here we report the near complete backbone chemical shift assignments for the lectin domain, as well as its predicted secondary structure. This data will provide a platform for future NMR studies to explore the role of lectin in biofilm formation.
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Affiliation(s)
- Rahul Yadav
- Department of Chemistry, Mississippi State University, Starkville, MS, 39762, USA
- Physical Sciences Department, University of Arkansas, Ft. Smith, AR, 72913, USA
| | - Tanveer Shaikh
- Department of Chemistry, Mississippi State University, Starkville, MS, 39762, USA
| | - Suhas Tikole
- Department of Chemistry, Mississippi State University, Starkville, MS, 39762, USA
| | - Andrew B Herr
- Department of Pediatrics, Division of Immunobiology, Cincinnati Children's Hospital Medical Center, University of Cincinnati School of Medicine, Cincinnati, OH, 45229, USA
| | - Nicholas C Fitzkee
- Department of Chemistry, Mississippi State University, Starkville, MS, 39762, USA.
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Snoussi M, Noumi E, Bouali N, Bazaid AS, Alreshidi MM, Altayb HN, Chaieb K. Antibiotic Susceptibility Profiling of Human Pathogenic Staphylococcus aureus Strains Using Whole Genome Sequencing and Genome-Scale Annotation Approaches. Microorganisms 2023; 11:1124. [PMID: 37317098 DOI: 10.3390/microorganisms11051124] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2023] [Revised: 04/22/2023] [Accepted: 04/24/2023] [Indexed: 06/16/2023] Open
Abstract
Staphylococcus species are major pathogens with increasing importance due to the rise in antibiotic resistance. Whole genome sequencing and genome-scale annotation are promising approaches to study the pathogenicity and dissemination of virulence factors in nosocomial methicillin-resistant and multidrug-resistant bacteria in intensive care units. Draft genome sequences of eight clinical S. aureus strains were assembled and annotated for the prediction of antimicrobial resistance genes, virulence factors, and phylogenetic analysis. Most of the studied S. aureus strains displayed multi-resistance toward the tested drugs, reaching more than seven drugs up to 12 in isolate S22. The mecA gene was detected in three isolates (S14, S21, and S23), mecC was identified in S8 and S9, and blaZ was commonly identified in all isolates except strain S23. Additionally, two complete mobile genomic islands coding for methicillin resistance SCCmec Iva (2B) were identified in strains S21 and S23. Numerous antimicrobial resistance genes (norA, norC, MgrA, tet(45), APH(3')-IIIa, and AAC(6')-APH(2″)) were identified in chromosomes of different strains. Plasmid analysis revealed the presence of blaZ, tetK, and ermC in different plasmid types, located in gene cassettes containing plasmid replicons (rep) and insertion sequences (IS). Additionally, the aminoglycoside-resistant determinants were identified in S1 (APH(3')-IIIa), while AAC(6)-APH(2″) was detected in strains S8 and S14. The trimethoprim (dfrC) resistance gene was detected in S. aureus S21, and the fosfomycin (fosB) resistance gene was detected only in S. aureus S14. We also noted that S. aureus S1 belongs to ST1-t127, which has been reported as one of the most frequent human pathogen types. Additionally, we noted the presence of rare plasmid-mediated mecC-MRSA in some of our isolates.
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Affiliation(s)
- Mejdi Snoussi
- Department of Biology, College of Science, University of Ha'il, Ha'il P.O. Box 2440, Saudi Arabia
- Medical and Diagnostic Research Centre, University of Ha'il, Ha'il 55473, Saudi Arabia
| | - Emira Noumi
- Department of Biology, College of Science, University of Ha'il, Ha'il P.O. Box 2440, Saudi Arabia
- Medical and Diagnostic Research Centre, University of Ha'il, Ha'il 55473, Saudi Arabia
| | - Nouha Bouali
- Department of Biology, College of Science, University of Ha'il, Ha'il P.O. Box 2440, Saudi Arabia
- Medical and Diagnostic Research Centre, University of Ha'il, Ha'il 55473, Saudi Arabia
| | - Abdulrahman S Bazaid
- Department of Medical, Laboratory Science, College of Applied Medical Sciences, University of Ha'il, Ha'il 55476, Saudi Arabia
| | - Mousa M Alreshidi
- Department of Biology, College of Science, University of Ha'il, Ha'il P.O. Box 2440, Saudi Arabia
- Medical and Diagnostic Research Centre, University of Ha'il, Ha'il 55473, Saudi Arabia
| | - Hisham N Altayb
- Department of Biochemistry, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia
- Center of Artificial Intelligence in Precision Medicines, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Kamel Chaieb
- Department of Biochemistry, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia
- Laboratory of Analysis, Treatment and Valorization of Pollutants of the Environmental and Products, Faculty of Pharmacy, University of Monastir, Monastir 5000, Tunisia
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10
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França A. The Role of Coagulase-Negative Staphylococci Biofilms on Late-Onset Sepsis: Current Challenges and Emerging Diagnostics and Therapies. Antibiotics (Basel) 2023; 12:antibiotics12030554. [PMID: 36978421 PMCID: PMC10044083 DOI: 10.3390/antibiotics12030554] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Revised: 02/24/2023] [Accepted: 03/06/2023] [Indexed: 03/12/2023] Open
Abstract
Infections are one of the most significant complications of neonates, especially those born preterm, with sepsis as one of the principal causes of mortality. Coagulase-negative staphylococci (CoNS), a group of staphylococcal species that naturally inhabit healthy human skin and mucosa, are the most common cause of late-onset sepsis, especially in preterms. One of the risk factors for the development of CoNS infections is the presence of implanted biomedical devices, which are frequently used for medications and/or nutrient delivery, as they serve as a scaffold for biofilm formation. The major concerns related to CoNS infections have to do with the increasing resistance to multiple antibiotics observed among this bacterial group and biofilm cells’ increased tolerance to antibiotics. As such, the treatment of CoNS biofilm-associated infections with antibiotics is increasingly challenging and considering that antibiotics remain the primary form of treatment, this issue will likely persist in upcoming years. For that reason, the development of innovative and efficient therapeutic measures is of utmost importance. This narrative review assesses the current challenges and emerging diagnostic tools and therapies for the treatment of CoNS biofilm-associated infections, with a special focus on late-onset sepsis.
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Affiliation(s)
- Angela França
- Centre of Biological Engineering, LIBRO—Laboratório de Investigação em Biofilmes Rosário Oliveira, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal;
- LABBELS—Associate Laboratory in Biotechnology and Bioengineering and Microelectromechanical Systems, Braga and Guimarães, Portugal
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11
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Clark LC, Atkin KE, Whelan F, Brentnall AS, Harris G, Towell AM, Turkenburg JP, Liu Y, Feizi T, Griffiths SC, Geoghegan JA, Potts JR. Staphylococcal Periscope proteins Aap, SasG, and Pls project noncanonical legume-like lectin adhesin domains from the bacterial surface. J Biol Chem 2023; 299:102936. [PMID: 36702253 PMCID: PMC9999234 DOI: 10.1016/j.jbc.2023.102936] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2022] [Revised: 01/08/2023] [Accepted: 01/18/2023] [Indexed: 01/25/2023] Open
Abstract
Staphylococcus aureus and Staphylococcus epidermidis are frequently associated with medical device infections that involve establishment of a bacterial biofilm on the device surface. Staphylococcal surface proteins Aap, SasG, and Pls are members of the Periscope Protein class and have been implicated in biofilm formation and host colonization; they comprise a repetitive region ("B region") and an N-terminal host colonization domain within the "A region," predicted to be a lectin domain. Repetitive E-G5 domains (as found in Aap, SasG, and Pls) form elongated "stalks" that would vary in length with repeat number, resulting in projection of the N-terminal A domain variable distances from the bacterial cell surface. Here, we present the structures of the lectin domains within A regions of SasG, Aap, and Pls and a structure of the Aap lectin domain attached to contiguous E-G5 repeats, suggesting the lectin domains will sit at the tip of the variable length rod. We demonstrate that these isolated domains (Aap, SasG) are sufficient to bind to human host desquamated nasal epithelial cells. Previously, proteolytic cleavage or a deletion within the A domain had been reported to induce biofilm formation; the structures suggest a potential link between these observations. Intriguingly, while the Aap, SasG, and Pls lectin domains bind a metal ion, they lack the nonproline cis peptide bond thought to be key for carbohydrate binding by the lectin fold. This suggestion of noncanonical ligand binding should be a key consideration when investigating the host cell interactions of these bacterial surface proteins.
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Affiliation(s)
- Laura C Clark
- Department of Biology, University of York, York, United Kingdom
| | - Kate E Atkin
- Department of Biology, University of York, York, United Kingdom
| | - Fiona Whelan
- Department of Biology, University of York, York, United Kingdom; Department of Molecular and Biomedical Science, School of Biological Sciences, University of Adelaide, South Australia, Australia.
| | | | - Gemma Harris
- Department of Biology, University of York, York, United Kingdom
| | - Aisling M Towell
- Department of Microbiology, Moyne Institute of Preventive Medicine, School of Genetics and Microbiology, Trinity College Dublin, Dublin, Ireland
| | | | - Yan Liu
- Glycosciences Laboratory, Department of Metabolism, Digestion and Reproduction, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Ten Feizi
- Glycosciences Laboratory, Department of Metabolism, Digestion and Reproduction, Faculty of Medicine, Imperial College London, London, United Kingdom
| | | | - Joan A Geoghegan
- Department of Microbiology, Moyne Institute of Preventive Medicine, School of Genetics and Microbiology, Trinity College Dublin, Dublin, Ireland; Institute of Microbiology and Infection, University of Birmingham, Birmingham, United Kingdom
| | - Jennifer R Potts
- Department of Biology, University of York, York, United Kingdom; School of Life and Environmental Sciences, University of Sydney, New South Wales, Australia.
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12
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Staphylococcus epidermidis and its dual lifestyle in skin health and infection. Nat Rev Microbiol 2023; 21:97-111. [PMID: 36042296 PMCID: PMC9903335 DOI: 10.1038/s41579-022-00780-3] [Citation(s) in RCA: 112] [Impact Index Per Article: 56.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/19/2022] [Indexed: 01/20/2023]
Abstract
The coagulase-negative bacterium Staphylococcus epidermidis is a member of the human skin microbiota. S. epidermidis is not merely a passive resident on skin but actively primes the cutaneous immune response, maintains skin homeostasis and prevents opportunistic pathogens from causing disease via colonization resistance. However, it is now appreciated that S. epidermidis and its interactions with the host exist on a spectrum of potential pathogenicity derived from its high strain-level heterogeneity. S. epidermidis is the most common cause of implant-associated infections and is a canonical opportunistic biofilm former. Additional emerging evidence suggests that some strains of S. epidermidis may contribute to the pathogenesis of common skin diseases. Here, we highlight new developments in our understanding of S. epidermidis strain diversity, skin colonization dynamics and its multifaceted interactions with the host and other members of the skin microbiota.
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13
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Maciag JJ, Chantraine C, Mills KB, Yadav R, Yarawsky AE, Chaton CT, Vinod D, Fitzkee NC, Mathelié-Guinlet M, Dufrêne YF, Fey PD, Horswill AR, Herr AB. Mechanistic basis of staphylococcal interspecies competition for skin colonization. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.26.525635. [PMID: 36747832 PMCID: PMC9900903 DOI: 10.1101/2023.01.26.525635] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Staphylococci, whether beneficial commensals or pathogens, often colonize human skin, potentially leading to competition for the same niche. In this multidisciplinary study we investigate the structure, binding specificity, and mechanism of adhesion of the Aap lectin domain required for Staphylococcus epidermidis skin colonization and compare its characteristics to the lectin domain from the orthologous Staphylococcus aureus adhesin SasG. The Aap structure reveals a legume lectin-like fold with atypical architecture, showing specificity for N-acetyllactosamine and sialyllactosamine. Bacterial adhesion assays using human corneocytes confirmed the biological relevance of these Aap-glycan interactions. Single-cell force spectroscopy experiments measured individual binding events between Aap and corneocytes, revealing an extraordinarily tight adhesion force of nearly 900 nN and a high density of receptors at the corneocyte surface. The SasG lectin domain shares similar structural features, glycan specificity, and corneocyte adhesion behavior. We observe cross-inhibition of Aap-and SasG-mediated staphylococcal adhesion to corneocytes. Together, these data provide insights into staphylococcal interspecies competition for skin colonization and suggest potential avenues for inhibition of S. aureus colonization.
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Affiliation(s)
- Joseph J. Maciag
- Division of Immunobiology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH
| | - Constance Chantraine
- Louvain Institute of Biomolecular Science and Technology, UCLouvain, Louvain-la-Neuve, Belgium
| | - Krista B. Mills
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO
| | - Rahul Yadav
- Department of Chemistry, Mississippi State University, Mississippi State, MS
| | - Alexander E. Yarawsky
- Division of Immunobiology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH
| | - Catherine T. Chaton
- Division of Immunobiology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH
| | - Divya Vinod
- Division of Immunobiology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH
- Medical Sciences Undergraduate Program, University of Cincinnati, Cincinnati, OH
| | - Nicholas C. Fitzkee
- Department of Chemistry, Mississippi State University, Mississippi State, MS
| | - Marion Mathelié-Guinlet
- Institut de Chimie et Biologie des Membranes et des Nano-Objets, CNRS UMR 5248, University of Bordeaux, Pessac, France
| | - Yves F. Dufrêne
- Louvain Institute of Biomolecular Science and Technology, UCLouvain, Louvain-la-Neuve, Belgium
| | - Paul D. Fey
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE
| | - Alexander R. Horswill
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO
| | - Andrew B. Herr
- Division of Immunobiology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH
- Division of Infectious Diseases, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH
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14
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Yarawsky AE, Ori AL, English LR, Whitten ST, Herr AB. Convergent behavior of extended stalk regions from staphylococcal surface proteins with widely divergent sequence patterns. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.06.523059. [PMID: 36711672 PMCID: PMC9881980 DOI: 10.1101/2023.01.06.523059] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Staphylococcus epidermidis and S. aureus are highly problematic bacteria in hospital settings. This stems, at least in part, from strong abilities to form biofilms on abiotic or biotic surfaces. Biofilms are well-organized multicellular aggregates of bacteria, which, when formed on indwelling medical devices, lead to infections that are difficult to treat. Cell wall-anchored (CWA) proteins are known to be important players in biofilm formation and infection. Many of these proteins have putative stalk-like regions or regions of low complexity near the cell wall-anchoring motif. Recent work demonstrated the strong propensity of the stalk region of the S. epidermidis accumulation-associated protein (Aap) to remain highly extended under solution conditions that typically induce compaction or other significant conformational changes. This behavior is consistent with the expected function of a stalk-like region that is covalently attached to the cell wall peptidoglycan and projects the adhesive domains of Aap away from the cell surface. In this study, we evaluate whether the ability to resist compaction is a common theme among stalk regions from various staphylococcal CWA proteins. Circular dichroism spectroscopy was used to examine secondary structure changes as a function of temperature and cosolvents along with sedimentation velocity analytical ultracentrifugation and SAXS to characterize structural characteristics in solution. All stalk regions tested are intrinsically disordered, lacking secondary structure beyond random coil and polyproline type II helix, and they all sample highly extended conformations. Remarkably, the Ser-Asp dipeptide repeat region of SdrC exhibited nearly identical behavior in solution when compared to the Aap Pro/Gly-rich region, despite highly divergent sequence patterns, indicating conservation of function by various distinct staphylococcal CWA protein stalk regions.
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Affiliation(s)
- Alexander E. Yarawsky
- Division of Immunobiology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH 45229, USA
| | - Andrea L. Ori
- Division of Immunobiology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH 45229, USA
- Medical Sciences Baccalaureate Program, University of Cincinnati, Cincinnati, OH 45267, USA
| | - Lance R. English
- Department of Chemistry and Biochemistry, Texas State University, San Marcos, TX 78666, USA
| | - Steven T. Whitten
- Department of Chemistry and Biochemistry, Texas State University, San Marcos, TX 78666, USA
| | - Andrew B. Herr
- Division of Immunobiology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH 45229, USA
- Division of Infectious Diseases, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH 45229, USA
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH 45229, USA
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15
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Wang C, Chantraine C, Viljoen A, Herr AB, Fey PD, Horswill AR, Mathelié-Guinlet M, Dufrêne YF. The staphylococcal biofilm protein Aap mediates cell-cell adhesion through mechanically distinct homophilic and lectin interactions. PNAS NEXUS 2022; 1:pgac278. [PMID: 36712378 PMCID: PMC9802226 DOI: 10.1093/pnasnexus/pgac278] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/10/2022] [Accepted: 12/01/2022] [Indexed: 12/04/2022]
Abstract
The accumulation phase of staphylococcal biofilms relies on both the production of an extracellular polysaccharide matrix and the expression of bacterial surface proteins. A prototypical example of such adhesive proteins is the long multidomain protein Aap (accumulation-associated protein) from Staphylococcus epidermidis, which mediates zinc-dependent homophilic interactions between Aap B-repeat regions through molecular forces that have not been investigated yet. Here, we unravel the remarkable mechanical strength of single Aap-Aap homophilic bonds between living bacteria and we demonstrate that intercellular adhesion also involves sugar binding through the lectin domain of the Aap A region. We find that the mechanical force needed to unfold individual β-sheet-rich G5-E domains from the Aap B-repeat regions is very high, ranging from 300 up to 1,000 pN at high loading rates, indicating these are extremely stable. This high mechanostability provides a means to the cells to form highly adhesive and cohesive biofilms capable of sustaining high physiological shear stress. Importantly, we identify a previously undescribed role of Aap in bacterial-bacterial adhesion, that is, heterophilic sugar binding by a specific lectin domain located in the N-terminal A region, which might be important to establish initial contacts between cells before strong homophilic bonds come into play. This study emphasizes the remarkable mechanical and binding properties of Aap as well as its wide diversity of adhesive functions.
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Affiliation(s)
| | | | - Albertus Viljoen
- Louvain Institute of Biomolecular Science and Technology, UCLouvain, Croix du Sud, 4-5, bte L7.07.07, B-1348 Louvain-la-Neuve, Belgium
| | - Andrew B Herr
- Divisions of Immunobiology and Infectious Diseases, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH 45229, USA
| | - Paul D Fey
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - Alexander R Horswill
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO 80045, USA
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16
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Yarawsky AE, Hopkins JB, Chatzimagas L, Hub JS, Herr AB. Solution Structural Studies of Pre-amyloid Oligomer States of the Biofilm Protein Aap. J Mol Biol 2022; 434:167708. [PMID: 35777467 PMCID: PMC9615840 DOI: 10.1016/j.jmb.2022.167708] [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: 05/11/2022] [Revised: 06/20/2022] [Accepted: 06/25/2022] [Indexed: 11/16/2022]
Abstract
Staphylococcus epidermidis is a commensal bacterium on human skin that is also the leading cause of medical device-related infections. The accumulation-associated protein (Aap) from S. epidermidis is a critical factor for infection via its ability to mediate biofilm formation. The B-repeat superdomain of Aap is composed of 5 to 17 Zn2+-binding B-repeats, which undergo rapid, reversible assembly to form dimer and tetramer species. The tetramer can then undergo a conformational change and nucleate highly stable functional amyloid fibrils. In this study, multiple techniques including analytical ultracentrifugation (AUC) and small-angle X-ray scattering (SAXS) are used to probe a panel of B-repeat mutant constructs that assemble to distinct oligomeric states to define the structural characteristics of B-repeat dimer and tetramer species. The B-repeat region from Aap forms an extremely elongated conformation that presents several challenges for standard SAXS analyses. Specialized approaches, such as cross-sectional analyses, allowed for in-depth interpretation of data, while explicit-solvent calculations via WAXSiS allowed for accurate evaluation of atomistic models. The resulting models suggest mechanisms by which Aap functional amyloid fibrils form, illuminating an important contributing factor to recurrent staphylococcal infections.
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Affiliation(s)
- Alexander E Yarawsky
- Division of Immunobiology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - Jesse B Hopkins
- The Biophysics Collaborative Access Team (BioCAT), Department of Biological Sciences, Illinois Institute of Technology, Chicago, IL, USA
| | - Leonie Chatzimagas
- Theoretical Physics and Center for Biophysics, Saarland University, Saarbrücken, Germany
| | - Jochen S Hub
- Theoretical Physics and Center for Biophysics, Saarland University, Saarbrücken, Germany
| | - Andrew B Herr
- Division of Immunobiology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA; Division of Infectious Diseases, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA; Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, USA.
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17
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Low Concentration of the Neutrophil Proteases Cathepsin G, Cathepsin B, Proteinase-3 and Metalloproteinase-9 Induce Biofilm Formation in Non-Biofilm-Forming Staphylococcus epidermidis Isolates. Int J Mol Sci 2022; 23:ijms23094992. [PMID: 35563384 PMCID: PMC9102557 DOI: 10.3390/ijms23094992] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Revised: 04/26/2022] [Accepted: 04/28/2022] [Indexed: 12/04/2022] Open
Abstract
Neutrophils play a crucial role in eliminating bacteria that invade the human body; however, cathepsin G can induce biofilm formation in a non-biofilm-forming Staphylococcus epidermidis 1457 strain, suggesting that neutrophil proteases may be involved in biofilm formation. Cathepsin G, cathepsin B, proteinase-3, and metalloproteinase-9 (MMP-9) from neutrophils were tested on the biofilm induction in commensal (skin isolated) and clinical non-biofilm-forming S. epidermidis isolates. From 81 isolates, 53 (74%) were aap+, icaA−, icaD− genotype, and without the capacity of biofilm formation under conditions of 1% glucose, 4% ethanol or 4% NaCl, but these 53 non-biofilm-forming isolates induced biofilm by the use of different neutrophil proteases. Of these, 62.3% induced biofilm with proteinase-3, 15% with cathepsin G, 10% with cathepsin B and 5% with MMP -9, where most of the protease-induced biofilm isolates were commensal strains (skin). In the biofilm formation kinetics analysis, the addition of phenylmethylsulfonyl fluoride (PMSF; a proteinase-3 inhibitor) showed that proteinase-3 participates in the cell aggregation stage of biofilm formation. A biofilm induced with proteinase-3 and DNAse-treated significantly reduced biofilm formation at an early time (initial adhesion stage of biofilm formation) compared to untreated proteinase-3-induced biofilm (p < 0.05). A catheter inoculated with a commensal (skin) non-biofilm-forming S. epidermidis isolate treated with proteinase-3 and another one without the enzyme were inserted into the back of a mouse. After 7 days of incubation period, the catheters were recovered and the number of grown bacteria was quantified, finding a higher amount of adhered proteinase-3-treated bacteria in the catheter than non-proteinase-3-treated bacteria (p < 0.05). Commensal non-biofilm-forming S. epidermidis in the presence of neutrophil cells significantly induced the biofilm formation when multiplicity of infection (MOI) 1:0.01 (neutrophil:bacteria) was used, but the addition of a cocktail of protease inhibitors impeded biofilm formation. A neutrophil:bacteria assay did not induce neutrophil extracellular traps (NETs). Our results suggest that neutrophils, in the presence of commensal non-biofilm-forming S. epidermidis, do not generate NETs formation. The effect of neutrophils is the production of proteases, and proteinase-3 releases bacterial DNA at the initial adhesion, favoring cell aggregation and subsequently leading to biofilm formation.
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18
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Rademacher F, Bartels J, Gläser R, Rodewald M, Schubert S, Drücke D, Rohde H, Harder J. Staphylococcus epidermidis-derived protease Esp mediates proteolytic activation of pro-IL-1beta in human keratinocytes. J Invest Dermatol 2022; 142:2756-2765.e8. [PMID: 35490742 DOI: 10.1016/j.jid.2022.04.010] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Revised: 04/03/2022] [Accepted: 04/07/2022] [Indexed: 11/16/2022]
Abstract
The gram-positive bacterium Staphylococcus epidermidis (SE) is an abundant skin commensal. It plays an important role in cutaneous defense by activation of IL-1 signaling. In keratinocytes, SE induces the release of mature IL-1beta. IL-1beta serves as an important cytokine of host defense. It contains an N-terminal prodomain that has to be cleaved off to generate active mature IL-1beta. Typically, processing and release of IL-1beta are associated with inflammasome assembly and activation of the protease caspase-1. Here we report that bacterial challenge of keratinocytes with SE induced the release of mature IL-1beta in a caspase-1-independent manner. Instead, the SE -derived serine protease Esp was identified as a pro-IL-1beta processing factor leading to a proteolytic maturation of active IL-1beta. Esp production and secretion by various SE strains correlated with their capacity to induce release of mature IL-1beta in human primary keratinocytes. Reconstitution of Esp-lacking SE strains with Esp enhanced their capacity to induce IL-1beta release in keratinocytes and skin. Intracellular abundance of pro-IL-1beta and cytotoxic effects of SE suggest release of pro-IL-1beta during injury followed by extracellular Esp-mediated processing to mature IL-1beta. These findings provide further insights into how a skin commensal interacts with keratinocytes to activate cutaneous host innate defense.
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Affiliation(s)
| | | | - Regine Gläser
- Department of Dermatology, Kiel University, Kiel, Germany
| | - Meno Rodewald
- Department of Dermatology, Kiel University, Kiel, Germany
| | - Sabine Schubert
- Institute of Infection Medicine, Kiel University, Kiel, Germany
| | - Daniel Drücke
- Department of Reconstructive Surgery, University Hospital Schleswig-Holstein, Campus Kiel, Kiel, Germany
| | - Holger Rohde
- Institute for Medical Microbiology, Virology and Hygiene, University Medical Center Hamburg-Eppendorf (UKE), Hamburg, Germany
| | - Jürgen Harder
- Department of Dermatology, Kiel University, Kiel, Germany.
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19
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Chen Y, Moran JC, Campbell-Lee S, Horsburgh MJ. Transcriptomic Responses and Survival Mechanisms of Staphylococci to the Antimicrobial Skin Lipid Sphingosine. Antimicrob Agents Chemother 2022; 66:e0056921. [PMID: 34902269 PMCID: PMC8846397 DOI: 10.1128/aac.00569-21] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Accepted: 11/17/2021] [Indexed: 11/20/2022] Open
Abstract
Sphingosines are antimicrobial lipids that form part of the innate barrier to skin colonization by microbes. Sphingosine deficiencies can result in increased epithelial infections by bacteria including Staphylococcus aureus. Recent studies have focused on the potential use of sphingosine resistance or its potential mechanisms. We used RNA-Seq to identify the common d-sphingosine transcriptomic response of the transient skin colonizer S. aureus and the dominant skin coloniser S. epidermidis. A common d-sphingosine stimulon was identified that included downregulation of the SaeSR two-component system (TCS) regulon and upregulation of both the VraSR TCS and CtsR stress regulons. We show that the PstSCAB phosphate transporter, and VraSR offer intrinsic resistance to d-sphingosine. Further, we demonstrate increased sphingosine resistance in these staphylococci evolves readily through mutations in genes encoding the FarE-FarR efflux/regulator proteins. The ease of selecting mutants with resistance to sphingosine may impact upon staphylococcal colonization of skin where the lipid is present and have implications with topical therapeutic applications.
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Affiliation(s)
- Yiyun Chen
- Staphylococcus Research Group, Institute of Infection Biology, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, UK
| | - Josephine C. Moran
- Staphylococcus Research Group, Institute of Infection Biology, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, UK
| | - Stuart Campbell-Lee
- Staphylococcus Research Group, Institute of Infection Biology, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, UK
| | - Malcolm J. Horsburgh
- Staphylococcus Research Group, Institute of Infection Biology, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, UK
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20
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Gutierrez-Gongora D, Geddes-McAlister J. Peptidases: promising antifungal targets of the human fungal pathogen, Cryptococcus neoformans. Facets (Ott) 2022. [DOI: 10.1139/facets-2021-0157] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Cryptococcus neoformans is a globally important fungal pathogen, primarily inflicting disease on immunocompromised individuals. The widespread use of antifungal agents in medicine and agriculture supports the development of antifungal resistance through evolution, and the emergence of new strains with intrinsic resistance drives the need for new therapeutics. For C. neoformans, the production of virulence factors, including extracellular peptidases (e.g., CnMpr-1 and May1) with mechanistic roles in tissue invasion and fungal survival, constitute approximately 2% of the fungal proteome and cover five classes of enzymes. Given their role in fungal virulence, peptidases represent promising targets for anti-virulence discovery in the development of new approaches against C. neoformans. Additionally, intracellular peptidases, which are involved in resistance mechanisms against current treatment options (e.g., azole drugs), as well as capsule biosynthesis and elaboration of virulence factors, present additional opportunities to combat the pathogen. In this review, we highlight key cryptococcal peptidases with defined or predicted roles in fungal virulence and assess sequence alignments against their human homologs. With this information, we define the feasibility of the select peptidases as “druggable” targets for inhibition, representing prospective therapeutic options against the deadly fungus.
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Affiliation(s)
- Davier Gutierrez-Gongora
- The Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario N1G 2W1, Canada
- Centro de Estudio de Proteínas, Facultad de Biología, Universidad de La Habana, La Habana, Cuba
| | - Jennifer Geddes-McAlister
- The Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario N1G 2W1, Canada
- Canadian Proteomics and Artificial Intelligence Research and Training Consortium
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21
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Abstract
The stratum corneum is the outermost layer of the epidermis and is thus directly exposed to the environment. It consists mainly of corneocytes, which are keratinocytes in the last stage of differentiation, having neither nuclei nor organelles. However, they retain keratin filaments embedded in filaggrin matrix and possess a lipid envelope which protects the body from desiccation. Despite the desiccated, nutrient-poor, and acidic nature of the skin making it a hostile environment for most microorganisms, this organ is colonized by commensal microbes. Among the classic skin commensals are Propionibacterium acnes and coagulase-negative staphylococci (CoNS) with Staphylococcus epidermidis as a leading species. An as-yet-unanswered question is what enables S. epidermis to colonize skin so successfully. In their recent article, P. D. Fey and his colleagues (P. Roy, A. R. Horswill, and P. D. Fey, mBio 12:e02908-20, 2021, https://doi.org/10.1128/mBio.02908-20) have brought us one step closer to answering this question.
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22
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Abstract
The human skin is our outermost layer and serves as a protective barrier against external insults. Advances in next generation sequencing have enabled the discoveries of a rich and diverse community of microbes - bacteria, fungi and viruses that are residents of this surface. The genomes of these microbes also revealed the presence of many secretory enzymes. In particular, proteases which are hydrolytic enzymes capable of protein cleavage and degradation are of special interest in the skin environment which is enriched in proteins and lipids. In this minireview, we will focus on the roles of these skin-relevant microbial secreted proteases, both in terms of their widely studied roles as pathogenic agents in tissue invasion and host immune inactivation, and their recently discovered roles in inter-microbial interactions and modulation of virulence factors. From these studies, it has become apparent that while microbial proteases are capable of a wide range of functions, their expression is tightly regulated and highly responsive to the environments the microbes are in. With the introduction of new biochemical and bioinformatics tools to study protease functions, it will be important to understand the roles played by skin microbial secretory proteases in cutaneous health, especially the less studied commensal microbes with an emphasis on contextual relevance.
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Glycan-Dependent Corneocyte Adherence of Staphylococcus epidermidis Mediated by the Lectin Subdomain of Aap. mBio 2021; 12:e0290820. [PMID: 34253065 PMCID: PMC8406310 DOI: 10.1128/mbio.02908-20] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Staphylococcus epidermidis and other coagulase-negative staphylococci (CoNS) that colonize skin are known to promote skin immunity and inhibit colonization of pathogens that cause skin and soft tissue infections, including Staphylococcus aureus. However, S. epidermidis adherence to corneocytes, the cells that constitute the uppermost layer of the skin epidermis, remains poorly understood. Our study documents that S. epidermidis corneocyte adherence is dependent upon the accumulation-associated protein (Aap). Aap is composed of two distinct A and B domains. The A domain is comprised of a repeat region and a conserved L-type lectin domain, whereas the fibrillar B domain, which is comprised of G5 and E repeats, is linked to the cell wall in a sortase-dependent manner. Our studies revealed that adherence to corneocytes is dependent upon the lectin subdomain within the A domain. However, significant adherence was only observed when the lectin domain was expressed with both the A repeat and the B domain, suggesting further interactions between these three domains. Our data also suggest that the A repeat domain is important for stability or expression of Aap. Deglycosylation treatment suggested that glycans expressed in the host stratum corneum serve as potential binding partners for Aap-mediated corneocyte adherence. Last, bioinformatic analyses of the predominant commensal species of CoNS identified open reading frames (ORFs) homologous to aap, thus suggesting that Aap orthologues containing lectin-like domains may provide the basis for staphylococcal colonization of skin. Corroborating these observations, adherence to corneocytes in an S. aureus mgrA mutant was dependent upon SasG, the Aap orthologue in S. aureus. IMPORTANCE Staphylococcus aureus is the most significant cause of skin and soft tissue infections yet it rarely colonizes the skin of healthy individuals. This is believed to be due, in part, to inhibition of colonization via toxic substances produced by normal skin flora, including by S. epidermidis. Furthermore, we surmise that S. aureus colonization inhibition may also be due to competition for binding sites on host corneocytes. To understand these potential interactions between S. aureus and S. epidermidis and, potentially, other coagulase-negative staphylococci, we must first understand how staphylococci adhere to corneocytes. This work documents that S. epidermidis adherence to corneocytes is dependent upon the fibrillar cell wall-associated protein Aap. Our work further documents that Aap binds to glycans exposed on the corneocyte surface, which are commonly exploited by bacteria to facilitate adherence to host cells. Furthermore, we find that Aap orthologues may be responsible for corneocyte adherence in other staphylococci, including in S. aureus.
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24
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Loza-Correa M, Yousuf B, Ramirez-Arcos S. Staphylococcus epidermidis undergoes global changes in gene expression during biofilm maturation in platelet concentrates. Transfusion 2021; 61:2146-2158. [PMID: 33904608 DOI: 10.1111/trf.16418] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Revised: 03/31/2021] [Accepted: 03/31/2021] [Indexed: 12/24/2022]
Abstract
BACKGROUND Staphylococcus epidermidis forms surface-attached aggregates (biofilms) when grown in platelet concentrates (PCs). Comparative transcriptome analyses were undertaken to investigate differential gene expression of S. epidermidis biofilms grown in PCs. STUDY DESIGN AND METHODS Two S. epidermidis strains isolated from human skin (AZ22 and AZ39) and one strain isolated from contaminated PCs (ST02) were grown in glucose-supplemented Trypticase Soy Broth (TSBg) and PCs. RNA was extracted and sequenced using Illumina HiSeq. Differential expression analysis was done using DESeq, and significantly differentially expressed genes (DEGs) were selected. DEGs were subjected to Kyoto encyclopedia of genes and genomes and Gene Ontology analyses. Differential gene expression was validated with quantitative reverse transcription-PCR. RESULTS A total of 436, 442, and 384 genes were expressed in AZ22, AZ39, and ST02, respectively. DEG analysis showed that 170, 172, and 117 genes were upregulated in PCs in comparison to TSBg, whereas 120, 135, and 89 genes were downregulated (p < .05) in mature biofilms of AZ22, AZ39, and ST02, respectively. Twenty-seven DEGs were shared by all three strains. While 76 DEGs were shared by AZ22 and AZ39, only 34 and 21 DEGs were common between ST02, and AZ22 and AZ39, respectively. Significant transcriptional expression changes were observed in genes involved in platelet-bacteria interaction, biofilm formation, production of virulence factors, and resistance to antimicrobial peptides and antibiotics. CONCLUSION Differential gene expression in S. epidermidis is triggered by the stressful PC storage environment. Upregulation of virulence and antimicrobial resistance genes could have clinical implications for transfusion patients.
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Affiliation(s)
- Maria Loza-Correa
- Centre for Innovation, Canadian Blood Services, Ottawa, Ontario, Canada
| | - Basit Yousuf
- Centre for Innovation, Canadian Blood Services, Ottawa, Ontario, Canada.,Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Ontario, Canada
| | - Sandra Ramirez-Arcos
- Centre for Innovation, Canadian Blood Services, Ottawa, Ontario, Canada.,Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Ontario, Canada
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25
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Monoclonal Antibodies Targeting Surface-Exposed and Secreted Proteins from Staphylococci. Vaccines (Basel) 2021; 9:vaccines9050459. [PMID: 34064471 PMCID: PMC8147999 DOI: 10.3390/vaccines9050459] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Revised: 04/14/2021] [Accepted: 04/30/2021] [Indexed: 02/01/2023] Open
Abstract
Staphylococci (specifically Staphylococcus aureus and Staphylococcus epidermidis) are the causative agents of diseases ranging from superficial skin and soft tissue infections to severe conditions such as fatal pneumonia, bacteremia, sepsis and endocarditis. The widespread and indiscriminate use of antibiotics has led to serious problems of resistance to staphylococcal disease and has generated a renewed interest in alternative therapeutic agents such as vaccines and antibodies. Staphylococci express a large repertoire of surface and secreted virulence factors, which provide mechanisms (adhesion, invasion and biofilm development among others) for both bacterial survival in the host and evasion from innate and adaptive immunity. Consequently, the development of antibodies that target specific antigens would provide an effective protective strategy against staphylococcal infections. In this review, we report an update on efforts to develop anti-staphylococci monoclonal antibodies (and their derivatives: minibodies, antibody–antibiotic conjugates) and the mechanism by which such antibodies can help fight infections. We also provide an overview of mAbs used in clinical trials and highlight their therapeutic potential in various infectious contexts.
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26
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França A, Gaio V, Lopes N, Melo LDR. Virulence Factors in Coagulase-Negative Staphylococci. Pathogens 2021; 10:170. [PMID: 33557202 PMCID: PMC7913919 DOI: 10.3390/pathogens10020170] [Citation(s) in RCA: 79] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 01/29/2021] [Accepted: 01/29/2021] [Indexed: 12/13/2022] Open
Abstract
Coagulase-negative staphylococci (CoNS) have emerged as major pathogens in healthcare-associated facilities, being S. epidermidis, S. haemolyticus and, more recently, S. lugdunensis, the most clinically relevant species. Despite being less virulent than the well-studied pathogen S. aureus, the number of CoNS strains sequenced is constantly increasing and, with that, the number of virulence factors identified in those strains. In this regard, biofilm formation is considered the most important. Besides virulence factors, the presence of several antibiotic-resistance genes identified in CoNS is worrisome and makes treatment very challenging. In this review, we analyzed the different aspects involved in CoNS virulence and their impact on health and food.
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Affiliation(s)
- Angela França
- Laboratory of Research in Biofilms Rosário Oliveira, Centre of Biological Engineering, University of Minho, 4710-057 Braga, Portugal; (V.G.); (N.L.)
| | | | | | - Luís D. R. Melo
- Laboratory of Research in Biofilms Rosário Oliveira, Centre of Biological Engineering, University of Minho, 4710-057 Braga, Portugal; (V.G.); (N.L.)
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27
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Kranjec C, Morales Angeles D, Torrissen Mårli M, Fernández L, García P, Kjos M, Diep DB. Staphylococcal Biofilms: Challenges and Novel Therapeutic Perspectives. Antibiotics (Basel) 2021; 10:131. [PMID: 33573022 PMCID: PMC7911828 DOI: 10.3390/antibiotics10020131] [Citation(s) in RCA: 74] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Revised: 01/21/2021] [Accepted: 01/27/2021] [Indexed: 12/14/2022] Open
Abstract
Staphylococci, like Staphylococcus aureus and S. epidermidis, are common colonizers of the human microbiota. While being harmless in many cases, many virulence factors result in them being opportunistic pathogens and one of the major causes of hospital-acquired infections worldwide. One of these virulence factors is the ability to form biofilms-three-dimensional communities of microorganisms embedded in an extracellular polymeric matrix (EPS). The EPS is composed of polysaccharides, proteins and extracellular DNA, and is finely regulated in response to environmental conditions. This structured environment protects the embedded bacteria from the human immune system and decreases their susceptibility to antimicrobials, making infections caused by staphylococci particularly difficult to treat. With the rise of antibiotic-resistant staphylococci, together with difficulty in removing biofilms, there is a great need for new treatment strategies. The purpose of this review is to provide an overview of our current knowledge of the stages of biofilm development and what difficulties may arise when trying to eradicate staphylococcal biofilms. Furthermore, we look into promising targets and therapeutic methods, including bacteriocins and phage-derived antibiofilm approaches.
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Affiliation(s)
- Christian Kranjec
- Faculty of Chemistry, Biotechnology and Food Science, The Norwegian University of Life Sciences, 1432 Ås, Norway; (C.K.); (D.M.A.); (M.T.M.)
| | - Danae Morales Angeles
- Faculty of Chemistry, Biotechnology and Food Science, The Norwegian University of Life Sciences, 1432 Ås, Norway; (C.K.); (D.M.A.); (M.T.M.)
| | - Marita Torrissen Mårli
- Faculty of Chemistry, Biotechnology and Food Science, The Norwegian University of Life Sciences, 1432 Ås, Norway; (C.K.); (D.M.A.); (M.T.M.)
| | - Lucía Fernández
- Department of Technology and Biotechnology of Dairy Products, Dairy Research Institute of Asturias (IPLA-CSIC), 33300 Villaviciosa, Spain; (L.F.); (P.G.)
- DairySafe Group, Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), 33011 Oviedo, Spain
| | - Pilar García
- Department of Technology and Biotechnology of Dairy Products, Dairy Research Institute of Asturias (IPLA-CSIC), 33300 Villaviciosa, Spain; (L.F.); (P.G.)
- DairySafe Group, Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), 33011 Oviedo, Spain
| | - Morten Kjos
- Faculty of Chemistry, Biotechnology and Food Science, The Norwegian University of Life Sciences, 1432 Ås, Norway; (C.K.); (D.M.A.); (M.T.M.)
| | - Dzung B. Diep
- Faculty of Chemistry, Biotechnology and Food Science, The Norwegian University of Life Sciences, 1432 Ås, Norway; (C.K.); (D.M.A.); (M.T.M.)
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28
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Kosolapova AO, Antonets KS, Belousov MV, Nizhnikov AA. Biological Functions of Prokaryotic Amyloids in Interspecies Interactions: Facts and Assumptions. Int J Mol Sci 2020; 21:E7240. [PMID: 33008049 PMCID: PMC7582709 DOI: 10.3390/ijms21197240] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Revised: 09/25/2020] [Accepted: 09/28/2020] [Indexed: 02/07/2023] Open
Abstract
Amyloids are fibrillar protein aggregates with an ordered spatial structure called "cross-β". While some amyloids are associated with development of approximately 50 incurable diseases of humans and animals, the others perform various crucial physiological functions. The greatest diversity of amyloids functions is identified within prokaryotic species where they, being the components of the biofilm matrix, function as adhesins, regulate the activity of toxins and virulence factors, and compose extracellular protein layers. Amyloid state is widely used by different pathogenic bacterial species in their interactions with eukaryotic organisms. These amyloids, being functional for bacteria that produce them, are associated with various bacterial infections in humans and animals. Thus, the repertoire of the disease-associated amyloids includes not only dozens of pathological amyloids of mammalian origin but also numerous microbial amyloids. Although the ability of symbiotic microorganisms to produce amyloids has recently been demonstrated, functional roles of prokaryotic amyloids in host-symbiont interactions as well as in the interspecies interactions within the prokaryotic communities remain poorly studied. Here, we summarize the current findings in the field of prokaryotic amyloids, classify different interspecies interactions where these amyloids are involved, and hypothesize about their real occurrence in nature as well as their roles in pathogenesis and symbiosis.
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Affiliation(s)
- Anastasiia O. Kosolapova
- Laboratory for Proteomics of Supra-Organismal Systems, All-Russia Research Institute for Agricultural Microbiology (ARRIAM), 196608 St. Petersburg, Russia (K.S.A.); (M.V.B.)
- Faculty of Biology, St. Petersburg State University (SPbSU), 199034 St. Petersburg, Russia
| | - Kirill S. Antonets
- Laboratory for Proteomics of Supra-Organismal Systems, All-Russia Research Institute for Agricultural Microbiology (ARRIAM), 196608 St. Petersburg, Russia (K.S.A.); (M.V.B.)
- Faculty of Biology, St. Petersburg State University (SPbSU), 199034 St. Petersburg, Russia
| | - Mikhail V. Belousov
- Laboratory for Proteomics of Supra-Organismal Systems, All-Russia Research Institute for Agricultural Microbiology (ARRIAM), 196608 St. Petersburg, Russia (K.S.A.); (M.V.B.)
- Faculty of Biology, St. Petersburg State University (SPbSU), 199034 St. Petersburg, Russia
| | - Anton A. Nizhnikov
- Laboratory for Proteomics of Supra-Organismal Systems, All-Russia Research Institute for Agricultural Microbiology (ARRIAM), 196608 St. Petersburg, Russia (K.S.A.); (M.V.B.)
- Faculty of Biology, St. Petersburg State University (SPbSU), 199034 St. Petersburg, Russia
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29
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Schilcher K, Horswill AR. Staphylococcal Biofilm Development: Structure, Regulation, and Treatment Strategies. Microbiol Mol Biol Rev 2020; 84:e00026-19. [PMID: 32792334 PMCID: PMC7430342 DOI: 10.1128/mmbr.00026-19] [Citation(s) in RCA: 380] [Impact Index Per Article: 76.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
In many natural and clinical settings, bacteria are associated with some type of biotic or abiotic surface that enables them to form biofilms, a multicellular lifestyle with bacteria embedded in an extracellular matrix. Staphylococcus aureus and Staphylococcus epidermidis, the most frequent causes of biofilm-associated infections on indwelling medical devices, can switch between an existence as single free-floating cells and multicellular biofilms. During biofilm formation, cells first attach to a surface and then multiply to form microcolonies. They subsequently produce the extracellular matrix, a hallmark of biofilm formation, which consists of polysaccharides, proteins, and extracellular DNA. After biofilm maturation into three-dimensional structures, the biofilm community undergoes a disassembly process that leads to the dissemination of staphylococcal cells. As biofilms are dynamic and complex biological systems, staphylococci have evolved a vast network of regulatory mechanisms to modify and fine-tune biofilm development upon changes in environmental conditions. Thus, biofilm formation is used as a strategy for survival and persistence in the human host and can serve as a reservoir for spreading to new infection sites. Moreover, staphylococcal biofilms provide enhanced resilience toward antibiotics and the immune response and impose remarkable therapeutic challenges in clinics worldwide. This review provides an overview and an updated perspective on staphylococcal biofilms, describing the characteristic features of biofilm formation, the structural and functional properties of the biofilm matrix, and the most important mechanisms involved in the regulation of staphylococcal biofilm formation. Finally, we highlight promising strategies and technologies, including multitargeted or combinational therapies, to eradicate staphylococcal biofilms.
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Affiliation(s)
- Katrin Schilcher
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, Colorado, USA
| | - Alexander R Horswill
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, Colorado, USA
- Department of Veterans Affairs Eastern Colorado Health Care System, Denver, Colorado, USA
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30
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Schilcher K, Horswill AR. Staphylococcal Biofilm Development: Structure, Regulation, and Treatment Strategies. Microbiol Mol Biol Rev 2020. [PMID: 32792334 DOI: 10.1128/mmbr.00026-19/asset/e] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/15/2023] Open
Abstract
In many natural and clinical settings, bacteria are associated with some type of biotic or abiotic surface that enables them to form biofilms, a multicellular lifestyle with bacteria embedded in an extracellular matrix. Staphylococcus aureus and Staphylococcus epidermidis, the most frequent causes of biofilm-associated infections on indwelling medical devices, can switch between an existence as single free-floating cells and multicellular biofilms. During biofilm formation, cells first attach to a surface and then multiply to form microcolonies. They subsequently produce the extracellular matrix, a hallmark of biofilm formation, which consists of polysaccharides, proteins, and extracellular DNA. After biofilm maturation into three-dimensional structures, the biofilm community undergoes a disassembly process that leads to the dissemination of staphylococcal cells. As biofilms are dynamic and complex biological systems, staphylococci have evolved a vast network of regulatory mechanisms to modify and fine-tune biofilm development upon changes in environmental conditions. Thus, biofilm formation is used as a strategy for survival and persistence in the human host and can serve as a reservoir for spreading to new infection sites. Moreover, staphylococcal biofilms provide enhanced resilience toward antibiotics and the immune response and impose remarkable therapeutic challenges in clinics worldwide. This review provides an overview and an updated perspective on staphylococcal biofilms, describing the characteristic features of biofilm formation, the structural and functional properties of the biofilm matrix, and the most important mechanisms involved in the regulation of staphylococcal biofilm formation. Finally, we highlight promising strategies and technologies, including multitargeted or combinational therapies, to eradicate staphylococcal biofilms.
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Affiliation(s)
- Katrin Schilcher
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, Colorado, USA
| | - Alexander R Horswill
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, Colorado, USA
- Department of Veterans Affairs Eastern Colorado Health Care System, Denver, Colorado, USA
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31
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Foster TJ. Surface Proteins of Staphylococcus epidermidis. Front Microbiol 2020; 11:1829. [PMID: 32849430 PMCID: PMC7403478 DOI: 10.3389/fmicb.2020.01829] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Accepted: 07/13/2020] [Indexed: 01/06/2023] Open
Abstract
Staphylococcus epidermidis is a ubiquitous commensal of human skin. The widespread use of indwelling medical devices in modern medicine provides an opportunity for it to cause infections. Disease causing isolates can come from many different genetic backgrounds. Multiply antibiotic resistant strains have spread globally. S. epidermidis has a smaller repertoire of cell wall anchored (CWA) surface proteins than Staphylococcus aureus. Nevertheless, these CWA proteins promote adhesion to components of the extracellular matrix including collagen, fibrinogen, and fibronectin and contribute to the formation of biofilm. The A domain of the accumulation associated protein Aap can promote adhesion to unconditioned biomaterial but must be removed proteolytically to allow accumulation to proceed by homophilic Zn2+-dependent interactions. Mature biofilm contains amyloid structures formed by Aap and the small basic protein (Sbp). The latter contributes to the integrity of both protein and polysaccharide biofilm matrices. Several other CWA proteins can also promote S. epidermidis biofilm formation.
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Affiliation(s)
- Timothy J Foster
- Department of Microbiology, Trinity College Dublin, Dublin, Ireland
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32
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Yarawsky AE, Herr AB. The staphylococcal biofilm protein Aap forms a tetrameric species as a necessary intermediate before amyloidogenesis. J Biol Chem 2020; 295:12840-12850. [PMID: 32665400 DOI: 10.1074/jbc.ra120.013936] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 06/29/2020] [Indexed: 11/06/2022] Open
Abstract
The accumulation-associated protein (Aap) from Staphylococcus epidermidis is a biofilm-related protein that was found to be a critical factor for infection using a rat catheter model. The B-repeat superdomain of Aap, composed of 5-17 B-repeats, each containing a Zn2+-binding G5 and a spacer subdomain, is responsible for Zn2+-dependent assembly leading to accumulation of bacteria during biofilm formation. We previously demonstrated that a minimal B-repeat construct (Brpt1.5) forms an antiparallel dimer in the presence of 2-3 Zn2+ ions. More recently, we have reported the presence of functional amyloid-like fibrils composed of Aap within S. epidermidis biofilms and demonstrated that a biologically relevant construct containing five and a half B-repeats (Brpt5.5) forms amyloid-like fibrils similar to those observed in the biofilm. In this study, we analyze the initial assembly events of the Brpt5.5 construct. Analytical ultracentrifugation was utilized to determine hydrodynamic parameters of reversibly associating species and to perform linked equilibrium studies. Linkage studies indicated a mechanism of Zn2+-induced dimerization similar to smaller constructs; however, Brpt5.5 dimers could then undergo further Zn2+-induced assembly into a previously uncharacterized tetramer. This led us to search for potential Zn2+-binding sites outside of the dimer interface. We developed a Brpt5.5 mutant that was unable to form the tetramer and was concordantly incapable of amyloidogenesis. CD and dynamic light scattering indicate that a conformational transition in the tetramer species is a critical step preceding amyloidogenesis. This mechanistic model for B-repeat assembly and amyloidogenesis provides new avenues for potential therapeutic targeting of staphylococcal biofilms.
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Affiliation(s)
- Alexander E Yarawsky
- Graduate Program in Molecular Genetics, Biochemistry, and Microbiology, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA; Division of Immunobiology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
| | - Andrew B Herr
- Division of Immunobiology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA; Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA; Division of Infectious Diseases, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA.
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33
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Lohse MB, Gulati M, Craik CS, Johnson AD, Nobile CJ. Combination of Antifungal Drugs and Protease Inhibitors Prevent Candida albicans Biofilm Formation and Disrupt Mature Biofilms. Front Microbiol 2020; 11:1027. [PMID: 32523574 PMCID: PMC7261846 DOI: 10.3389/fmicb.2020.01027] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Accepted: 04/27/2020] [Indexed: 02/04/2023] Open
Abstract
Biofilms formed by the fungal pathogen Candida albicans are resistant to many of the antifungal agents commonly used in the clinic. Previous reports suggest that protease inhibitors, specifically inhibitors of aspartyl proteases, could be effective antibiofilm agents. We screened three protease inhibitor libraries, containing a total of 80 compounds for the abilities to prevent C. albicans biofilm formation and to disrupt mature biofilms. The compounds were screened individually and in the presence of subinhibitory concentrations of the most commonly prescribed antifungal agents for Candida infections: fluconazole, amphotericin B, or caspofungin. Although few of the compounds affected biofilms on their own, seven aspartyl protease inhibitors inhibited biofilm formation when combined with amphotericin B or caspofungin. Furthermore, nine aspartyl protease inhibitors disrupted mature biofilms when combined with caspofungin. These results suggest that the combination of standard antifungal agents together with specific protease inhibitors may be useful in the prevention and treatment of C. albicans biofilm infections.
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Affiliation(s)
- Matthew B Lohse
- Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, CA, United States.,Department of Biology, BioSynesis, Inc., San Francisco, CA, United States
| | - Megha Gulati
- Department of Molecular and Cell Biology, University of California, Merced, Merced, CA, United States
| | - Charles S Craik
- Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, CA, United States
| | - Alexander D Johnson
- Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, CA, United States
| | - Clarissa J Nobile
- Department of Molecular and Cell Biology, University of California, Merced, Merced, CA, United States
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34
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Yarawsky AE, Johns SL, Schuck P, Herr AB. The biofilm adhesion protein Aap from Staphylococcus epidermidis forms zinc-dependent amyloid fibers. J Biol Chem 2020; 295:4411-4427. [PMID: 32102851 DOI: 10.1074/jbc.ra119.010874] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Revised: 02/23/2020] [Indexed: 12/17/2022] Open
Abstract
The skin-colonizing commensal bacterium Staphylococcus epidermidis is a leading cause of hospital-acquired and device-related infections. Its pathogenicity in humans is largely due to its propensity to form biofilms, surface-adherent bacterial accumulations that are remarkably resistant to chemical and physical stresses. Accumulation-associated protein (Aap) from S. epidermidis has been shown to be necessary and sufficient for mature biofilm formation and catheter infection. Aap contains up to 17 tandem B-repeat domains, capable of zinc-dependent assembly into twisted, rope-like intercellular filaments in the biofilm. Using microscopic and biophysical techniques, we show here that Aap B-repeat constructs assemble further into zinc-dependent functional amyloid fibers. We observed such amyloid fibers by confocal microscopy during both early and late stages of S. epidermidis biofilm formation, and we confirmed that extracellular fibrils from these biofilms contain Aap. Unlike what has been observed for amyloidogenic biofilm proteins from other bacteria, which typically use chaperones or initiator proteins to initiate amyloid assembly, our findings indicate that Aap from S. epidermidis requires Zn2+ as a catalyst that drives amyloid fiber formation, similar to many mammalian amyloid-forming proteins that require metals for assembly. This work provides detailed insights into S. epidermidis biofilm formation and architecture that improve our understanding of persistent staphylococcal infections.
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Affiliation(s)
- Alexander E Yarawsky
- Graduate Program in Molecular Genetics, Biochemistry and Microbiology, University of Cincinnati College of Medicine, Cincinnati, Ohio 45267.,Division of Immunobiology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio 45229
| | - Stefanie L Johns
- Graduate Program in Molecular Genetics, Biochemistry and Microbiology, University of Cincinnati College of Medicine, Cincinnati, Ohio 45267
| | - Peter Schuck
- Dynamics of Macromolecular Assembly Section, Laboratory of Cellular Imaging and Bioengineering, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, Maryland 20814
| | - Andrew B Herr
- Division of Immunobiology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio 45229 .,Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio 45229.,Division of Infectious Diseases, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio 45229
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35
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Walker JN, Pinkner CL, Lynch AJL, Ortbal S, Pinkner JS, Hultgren SJ, Myckatyn TM. Deposition of Host Matrix Proteins on Breast Implant Surfaces Facilitates Staphylococcus Epidermidis Biofilm Formation: In Vitro Analysis. Aesthet Surg J 2020; 40:281-295. [PMID: 30953053 DOI: 10.1093/asj/sjz099] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Staphylococcus epidermidis is a primary cause of breast implant-associated infection. S epidermidis possesses several virulence factors that enable it to bind both abiotic surfaces and host factors to form a biofilm. In addition S epidermidis colocalizes with matrix proteins coating explanted human breast implants. OBJECTIVES The authors sought to identify matrix proteins that S epidermidis may exploit to infect various breast implant surfaces in vitro. METHODS A combination of in vitro assays was used to characterize S epidermidis strains isolated from human breast implants to gain a better understanding of how these bacteria colonize breast implant surfaces. These included determining the (1) minimum inhibitory and bactericidal concentrations for irrigation solutions commonly used to prevent breast implant contamination; (2) expression and carriage of polysaccharide intercellular adhesin and serine-aspartate repeat proteins, which bind fibrinogen (SdrG) and collagen (SdrF), respectively; and (3) biofilm formation on varying implant surface characteristics, in different growth media, and supplemented with fibrinogen and Types I and III collagen. Scanning electron microscopy and immunofluorescence staining analyses were performed to corroborate findings from these assays. RESULTS Textured breast implant surfaces support greater bacterial biofilm formation at baseline, and the addition of collagen significantly increases biomass on all surfaces tested. We found that S epidermidis isolated from breast implants all encoded SdrF. Consistent with this finding, these strains had a clear affinity for Type I collagen, forming dense, highly structured biofilms in its presence. CONCLUSIONS The authors found that S epidermidis may utilize SdrF to interact with Type I collagen to form biofilm on breast implant surfaces. LEVEL OF EVIDENCE: 5
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Affiliation(s)
| | | | | | - Sarah Ortbal
- Washington University School of Medicine, St. Louis, MO
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Martínez-García S, Ortega-Peña S, De Haro-Cruz MDJ, Aguilera-Arreola MG, Alcántar-Curiel MD, Betanzos-Cabrera G, Jan-Roblero J, Pérez-Tapia SM, Rodríguez-Martínez S, Cancino-Diaz ME, Cancino-Diaz JC. Non-biofilm-forming commensal Staphylococcus epidermidis isolates produce biofilm in the presence of trypsin. Microbiologyopen 2019; 8:e906. [PMID: 31389671 PMCID: PMC6813491 DOI: 10.1002/mbo3.906] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Revised: 06/11/2019] [Accepted: 06/28/2019] [Indexed: 01/13/2023] Open
Abstract
Epidemiological studies comparing clinical and commensal Staphylococcus epidermidis isolates suggest that biofilm formation is a discriminant biomarker. A study showed that four non-biofilm-forming clinical S. epidermidis isolates could form an induced biofilm by trypsin treatment, suggesting that S. epidermidis can form biofilms in a protease-independent way and in a trypsin-induced way. In this study, the trypsin capacity to induce biofilm formation was evaluated in non-biofilm-forming S. epidermidis isolates (n = 133) in order to support this mechanism and to establish the importance of total biofilms (meaning the sum of protease-independent biofilm and trypsin-induced biofilm). Staphylococcus epidermidis isolates from ocular infections (OI; n = 24), prosthetic joint infections (PJI; n = 64), and healthy skin (HS-1; n = 100) were screened for protease-independent biofilm formation according to Christensen's method. The result was that there are significant differences (p < .0001) between clinical (43.2%) and commensal (17%) protease-independent biofilm producers. Meanwhile, non-biofilm-forming isolates were treated with trypsin, and biofilm formation was evaluated by the same method. The number of commensal trypsin-induced biofilm producers significantly increased from 17% to 79%. In contrast, clinical isolates increased from 43.2% to 72.7%. The comparison between clinical and commensal total biofilm yielded no significant differences (p = .392). A similar result was found when different isolation sources were compared (OI vs. HS-1 and PJI vs. HS-1). The genotype icaA- /aap+ was associated with the trypsin-induced biofilm phenotype; however, no correlation was observed between aap mRNA expression and the level of trypsin-induced biofilm phenotype. Studying another group of commensal S. epidermidis non-biofilm-forming isolates (HS-2; n = 139) from different body sites, it was found that 70 isolates (60.3%) formed trypsin-induced biofilms. In conclusion, trypsin is capable of inducing biofilm production in non-biofilm-forming commensal S. epidermidis isolates with the icaA- /aap+ genotype, and there is no significant difference in total biofilms when comparing clinical and commensal isolates, suggesting that total biofilms are not a discriminant biomarker.
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Affiliation(s)
- Sergio Martínez-García
- Laboratory of Immunomicrobiology, Department of Microbiology, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Mexico City, Mexico
| | - Silvestre Ortega-Peña
- Laboratory of Immunomicrobiology, Department of Microbiology, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Mexico City, Mexico.,Laboratory of Infectology, Instituto Nacional de Rehabilitación "Luis Guillermo Ibarra Ibarra", Mexico City, Mexico
| | - María De Jesús De Haro-Cruz
- Laboratory of Veterinary Microbiology, Department of Microbiology, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Mexico City, Mexico
| | - Ma Guadalupe Aguilera-Arreola
- Laboratory of Medical Bacteriology, Department of Microbiology, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Mexico City, Mexico
| | - María Dolores Alcántar-Curiel
- Unidad de Investigación en Medicina Experimental, Facultad de Medicina, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | | | - Janet Jan-Roblero
- Laboratory of Environmental Biotechnology, Department of Microbiology, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Mexico City, Mexico
| | - Sonia Mayra Pérez-Tapia
- Unidad de Desarrollo e Investigación en Bioprocesos" (UDIBI), Department of Immunology, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Mexico City, Mexico
| | - Sandra Rodríguez-Martínez
- Laboratory of Innate Immunity, Department of Immunology, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Mexico City, Mexico
| | - Mario E Cancino-Diaz
- Laboratory of Innate Immunity, Department of Immunology, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Mexico City, Mexico
| | - Juan C Cancino-Diaz
- Laboratory of Immunomicrobiology, Department of Microbiology, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Mexico City, Mexico
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Abstract
Staphylococci, with the leading species Staphylococcus aureus and Staphylococcus epidermidis, are the most frequent causes of infections on indwelling medical devices. The biofilm phenotype that those bacteria adopt during device-associated infection facilitates increased resistance to antibiotics and host immune defenses. This review presents and discusses the molecular mechanisms contributing to staphylococcal biofilm development and their in-vivo importance. Furthermore, it summarizes current strategies for the development of therapeutics against staphylococcal biofilm-associated infection.
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Alabdullatif M, Ramirez-Arcos S. Biofilm-associated accumulation-associated protein (Aap): A contributing factor to the predominant growth of Staphylococcus epidermidis
in platelet concentrates. Vox Sang 2018; 114:28-37. [DOI: 10.1111/vox.12729] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Revised: 10/26/2018] [Accepted: 10/29/2018] [Indexed: 01/13/2023]
Affiliation(s)
- Meshari Alabdullatif
- Centre for Innovation; Canadian Blood Services and Department of Biochemistry, Microbiology and Immunology; University of Ottawa; Ottawa ON Canada
| | - Sandra Ramirez-Arcos
- Centre for Innovation; Canadian Blood Services and Department of Biochemistry, Microbiology and Immunology; University of Ottawa; Ottawa ON Canada
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Heilmann C, Ziebuhr W, Becker K. Are coagulase-negative staphylococci virulent? Clin Microbiol Infect 2018; 25:1071-1080. [PMID: 30502487 DOI: 10.1016/j.cmi.2018.11.012] [Citation(s) in RCA: 176] [Impact Index Per Article: 25.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Revised: 11/06/2018] [Accepted: 11/11/2018] [Indexed: 02/06/2023]
Abstract
BACKGROUND Progress in contemporary medicine is associated with an increasing number of immunocompromised individuals. In this vulnerable group, the underlying disease together with long-term hospitalization and the use of medical devices facilitate infections by opportunistic pathogens, of which coagulase-negative staphylococci (CoNS) represent a prime example. OBJECTIVES The diversity of CoNS with species- and strain-specific differences concerning virulence and clinical impact is highlighted. A focus is on the ability of CoNS to generate biofilms on biotic and abiotic surfaces, which enables skin and mucosa colonization as well as establishment of CoNS on indwelling foreign bodies. SOURCES Literature about the virulence of CoNS listed in PubMed was reviewed. CONTENT Most catheter-related and prosthetic joint infections as well as most other device-related infections are caused by CoNS, specifically by Staphylococcus epidermidis and Staphylococcus haemolyticus. A common theme of CoNS infections is a high antibiotic resistance rate, which often limits treatment options and contributes to the significant health and economic burden imposed by CoNS. IMPLICATIONS Breaching the skin barrier along with the insertion of medical devices offers CoNS opportunities to gain access to host tissues and to sustain there by forming biofilms on foreign body surfaces. Biofilms represent the perfect niche to protect CoNS from both the host immune response and the action of antibiotics. Their particular lifestyle, combined with conditions that facilitate host colonization and infection, has led to the growing impact of CoNS as pathogens. Moreover, CoNS may serve as hidden reservoirs for antibiotic resistance and virulence traits.
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Affiliation(s)
- C Heilmann
- Institute of Medical Microbiology, University Hospital Münster, Münster, Germany
| | - W Ziebuhr
- Institute for Molecular Infection Biology, University of Würzburg, Würzburg, Germany
| | - K Becker
- Institute of Medical Microbiology, University Hospital Münster, Münster, Germany.
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Martínez-García S, Rodríguez-Martínez S, Cancino-Diaz ME, Cancino-Diaz JC. Extracellular proteases of Staphylococcus epidermidis: roles as virulence factors and their participation in biofilm. APMIS 2018; 126:177-185. [PMID: 29399876 DOI: 10.1111/apm.12805] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Accepted: 11/15/2017] [Indexed: 01/22/2023]
Abstract
Staphylococci produce a large number of extracellular proteases, some of which are considered as potential virulence factors. Staphylococcus epidermidis is a causative agent of nosocomial infections in medical devices by the formation of biofilms. It has been proposed that proteases contribute to the different stages of biofilm formation. S. epidermidis secretes a small number of extracellular proteases, such as serine protease Esp, cysteine protease EcpA, and metalloprotease SepA that have a relatively low substrate specificity. Recent findings indicate a significant contribution of extracellular proteases in biofilm formation through the proteolytic inactivation of adhesion molecules. The objective of this work is to provide an overview of the current knowledge of S. epidermidis' extracellular proteases during pathogenicity, especially in the different stages of biofilm formation.
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Affiliation(s)
- Sergio Martínez-García
- Departamento de Microbiología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Ciudad de México, Mexico
| | - Sandra Rodríguez-Martínez
- Departamento de Inmunología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Ciudad de México, Mexico
| | - Mario E Cancino-Diaz
- Departamento de Inmunología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Ciudad de México, Mexico
| | - Juan C Cancino-Diaz
- Departamento de Microbiología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Ciudad de México, Mexico
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Abstract
PURPOSE OF REVIEW Atopic dermatitis (AD) is a chronic, relapsing inflammatory skin disorder that is a major public health burden worldwide. AD lesions are often colonized by Staphylococcus aureus and Staphylococcus epidermidis. An important aspect of Staphylococcus spp. is their propensity to form biofilms, adhesive surface-attached colonies that become highly resistant to antibiotics and immune responses, and recent studies have found that clinical isolates colonizing AD skin are often biofilm-positive. Biofilm formation results in complex bacterial communities that have unique effects on keratinocytes and host immunity. This review will summarize recent studies exploring the role of staphyloccocal biofilms in atopic dermatitis and the implications for treatment. RECENT FINDINGS Recent studies suggest an important role for biofilms in the pathogenesis of numerous dermatologic diseases including AD. S. aureus biofilms have been found to colonize the eccrine ducts of AD skin, and these biofilms influence secretion of keratinocyte cytokines and trigger differentiation and apoptosis of keratinocytes. These activities may act to disrupt barrier function and promote disease pathogenesis as well as allergen sensitization. Formation of biofilm is a successful strategy that protects the bacteria from environmental danger, antibiotics, and phagocytosis, enabling chronic persistence in the host. An increasing number of S. aureus skin isolates are resistant to conventional antibiotics, and staphylococcal biofilm communities are prevalent on the skin of individuals with AD. Staphylococcal colonization of the skin impacts skin barrier function and plays multiple important roles in AD pathogenesis.
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Chaton CT, Herr AB. Defining the metal specificity of a multifunctional biofilm adhesion protein. Protein Sci 2017; 26:1964-1973. [PMID: 28707417 DOI: 10.1002/pro.3232] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Revised: 07/05/2017] [Accepted: 07/07/2017] [Indexed: 12/12/2022]
Abstract
The accumulation associated protein (Aap) of Staphylococcus epidermidis mediates intercellular adhesion events necessary for biofilm growth. This process depends upon Zn2+ -induced self-assembly of G5 domains within the B-repeat region of the protein, forming anti-parallel, intertwined protein "ropes" between cells. Pleomorphism in the Zn2+ -coordinating residues was observed in previously solved crystal structures, suggesting that the metal binding site might accommodate other transition metals and thereby support dimerization. By use of carefully selected buffer systems and a specialized approach to analyze sedimentation velocity analytical ultracentrifugation data, we were able to analyze low-affinity metal binding events in solution. Our data show that both Zn2+ and Cu2+ support B-repeat assembly, whereas Mn2+ , Co2+ , and Ni2+ bind to Aap but do not support self-association. As the number of G5 domains are increased in longer B-repeat constructs, the total concentration of metal required for dimerization decreases and the transition between monomer and dimer becomes more abrupt. These characteristics allow Aap to function as an environmental sensor that regulates biofilm formation in response to local concentrations of Zn2+ and Cu2+ , both of which are implicated in immune cell activity.
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Affiliation(s)
- Catherine T Chaton
- Graduate Program in Molecular Genetics, Biochemistry and Microbiology, University of Cincinnati College of Medicine, Cincinnati, Ohio.,Division of Immunobiology and Center for Systems Immunology, Division of Infectious Diseases, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, 45229
| | - Andrew B Herr
- Division of Immunobiology and Center for Systems Immunology, Division of Infectious Diseases, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, 45229
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43
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Galac MR, Stam J, Maybank R, Hinkle M, Mack D, Rohde H, Roth AL, Fey PD. Complete Genome Sequence of Staphylococcus epidermidis 1457. GENOME ANNOUNCEMENTS 2017; 5:e00450-17. [PMID: 28572323 PMCID: PMC5454206 DOI: 10.1128/genomea.00450-17] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Accepted: 04/12/2017] [Indexed: 02/07/2023]
Abstract
Staphylococcus epidermidis 1457 is a frequently utilized strain that is amenable to genetic manipulation and has been widely used for biofilm-related research. We report here the whole-genome sequence of this strain, which encodes 2,277 protein-coding genes and 81 RNAs within its 2.4-Mb genome and plasmid.
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Affiliation(s)
- Madeline R Galac
- Multidrug-Resistant Organism Repository and Surveillance Network (MRSN), Walter Reed Army Institute of Research, Silver Spring, Maryland, USA
| | - Jason Stam
- Multidrug-Resistant Organism Repository and Surveillance Network (MRSN), Walter Reed Army Institute of Research, Silver Spring, Maryland, USA
| | - Rosslyn Maybank
- Multidrug-Resistant Organism Repository and Surveillance Network (MRSN), Walter Reed Army Institute of Research, Silver Spring, Maryland, USA
| | - Mary Hinkle
- Multidrug-Resistant Organism Repository and Surveillance Network (MRSN), Walter Reed Army Institute of Research, Silver Spring, Maryland, USA
| | - Dietrich Mack
- Institut für Medizinische Diagnostik GmbH, Bioscientia Labor Ingelheim, Ingelheim, Germany
| | - Holger Rohde
- Institut für Medizinische Mikrobiologie, Virologie & Hygiene, Universitätsklinikum Hamburg-Eppendorf, Hamburg, Germany
| | - Amanda L Roth
- Multidrug-Resistant Organism Repository and Surveillance Network (MRSN), Walter Reed Army Institute of Research, Silver Spring, Maryland, USA
| | - Paul D Fey
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, Nebraska, USA
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