1
|
David A, Tahrioui A, Tareau AS, Forge A, Gonzalez M, Bouffartigues E, Lesouhaitier O, Chevalier S. Pseudomonas aeruginosa Biofilm Lifecycle: Involvement of Mechanical Constraints and Timeline of Matrix Production. Antibiotics (Basel) 2024; 13:688. [PMID: 39199987 PMCID: PMC11350761 DOI: 10.3390/antibiotics13080688] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2024] [Revised: 07/22/2024] [Accepted: 07/23/2024] [Indexed: 09/01/2024] Open
Abstract
Pseudomonas aeruginosa is an opportunistic pathogen causing acute and chronic infections, especially in immunocompromised patients. Its remarkable adaptability and resistance to various antimicrobial treatments make it difficult to eradicate. Its persistence is enabled by its ability to form a biofilm. Biofilm is a community of sessile micro-organisms in a self-produced extracellular matrix, which forms a scaffold facilitating cohesion, cell attachment, and micro- and macro-colony formation. This lifestyle provides protection against environmental stresses, the immune system, and antimicrobial treatments, and confers the capacity for colonization and long-term persistence, often characterizing chronic infections. In this review, we retrace the events of the life cycle of P. aeruginosa biofilm, from surface perception/contact to cell spreading. We focus on the importance of extracellular appendages, mechanical constraints, and the kinetics of matrix component production in each step of the biofilm life cycle.
Collapse
Affiliation(s)
| | | | | | | | | | | | | | - Sylvie Chevalier
- Univ Rouen Normandie, Univ Caen Normandie, Normandie Univ, CBSA UR 4312, F-76000 Rouen, France
| |
Collapse
|
2
|
Barajas B, Kurtz IS, Waldman AJ, Schiffman JD. Stiffness and Oligomer Content Affect the Initial Adhesion of Staphylococcus aureus to Polydimethylsiloxane Gels. ACS APPLIED MATERIALS & INTERFACES 2023. [PMID: 37922414 DOI: 10.1021/acsami.3c11349] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/05/2023]
Abstract
The growing prevalence of methicillin-resistant Staphylococcus aureus (S. aureus) infections necessitates a greater understanding of their initial adhesion to medically relevant surfaces. In this study, the influence of the mechanical properties and oligomer content of polydimethylsiloxane (PDMS) gels on the initial attachment of Gram-positive S. aureus was explored. Small-amplitude oscillatory shear rheological measurements were conducted to verify that by altering the base to curing (B:C) ratio of the commonly used Sylgard 184 silicone elastomer kit (B:C ratios of 60:1, 40:1, 10:1, and 5:1), PDMS gels could be synthesized with Young's moduli across four distinct regimes: ultrasoft (15 kPa), soft (30 kPa), standard (400 kPa), and stiff (1500 kPa). These as-prepared gels (unextracted) were compared to gels prepared from the same B/C ratios that underwent Soxhlet extraction to remove any unreacted oligomers. While the Young's moduli of unextracted and extracted PDMS gels prepared from the same B:C ratio were statistically equivalent, the associated adhesion failure energy statistically decreased for the ultrasoft gels after extraction (from 25 to 8 J/mm2). The interactions of these eight well-characterized gels with bacteria were tested by using S. aureus SH1000, a commonly studied laboratory strain, as well as S. aureus ATCC 12600, which was isolated from a human lung infection. Increased S. aureus inactivation occurred only when the bacteria were incubated directly on top of the unextracted gels prepared at high B:C ratios (40:1 and 60:1), whereas none of the extracted gels (no unreacted oligomers) had significant levels of inactivated bacteria. S. aureus adhered the least to the stiffest extracted PDMS gels (no unreacted oligomers) and the most to soft, unextracted PDMS gels (with ∼17% unreacted oligomers). These findings suggest that both unreacted oligomers and Young's moduli are important material factors to consider when exploring the attachment behavior of Gram-positive S. aureus to hydrophobic elastomer gels.
Collapse
Affiliation(s)
- Brandon Barajas
- Department of Chemical Engineering, University of Massachusetts Amherst, Amherst, Massachusetts 01003-9303, United States
| | - Irene S Kurtz
- Department of Chemical Engineering, University of Massachusetts Amherst, Amherst, Massachusetts 01003-9303, United States
| | - Abraham J Waldman
- Department of Chemical Engineering, University of Massachusetts Amherst, Amherst, Massachusetts 01003-9303, United States
| | - Jessica D Schiffman
- Department of Chemical Engineering, University of Massachusetts Amherst, Amherst, Massachusetts 01003-9303, United States
| |
Collapse
|
3
|
Sun J, Wang K, Hao R, Zhang Z, Feng Z, Shi Z, Yuan W, Jing Z, Zhang L. Disregarded Free Chains Affect Bacterial Adhesion on Cross-Linked Polydimethylsiloxane Surfaces. ACS APPLIED MATERIALS & INTERFACES 2023. [PMID: 37466242 DOI: 10.1021/acsami.3c05477] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/20/2023]
Abstract
The surface properties exhibited by chemically cross-linked polydimethylsiloxanes (CPDMS) such as morphology, stiffness, and wettability have garnered great interest in the study of bacteria-material interactions. Nevertheless, the hidden factor of uncross-linked free PDMS chains that dissociate in CPDMS has often been overlooked when studying the biofilm formation on these polymeric elastomer surfaces. Here, we undertake a comparative characterization of the effects of free chains in CPDMS on bacterial adhesion to both flat and textured Sharklet CPDMS surfaces. Surprisingly, compared to unextracted surfaces, removing free chains from flat and textured CPDMS through solvent extraction results in a tremendous increase in bacterial colony-forming units for both Gram-negative and Gram-positive bacteria up to 2-3 orders in the initial adhesion stage of 2 h. These findings demonstrate that the solvent extraction of free chains from CPDMS is essential in studying the interactions between bacteria and silicone elastomer materials when focusing on a single variable.
Collapse
Affiliation(s)
- Jining Sun
- School of Mechanical Engineering, Dalian University of Technology, Dalian 116024, China
- State Key Laboratory of High-Performance Precision Manufacturing, Dalian University of Technology, Dalian 116024, China
| | - Kunwen Wang
- School of Mechanical Engineering, Dalian University of Technology, Dalian 116024, China
| | - Ruonan Hao
- School of Mechanical Engineering, Dalian University of Technology, Dalian 116024, China
| | - Zhiyuan Zhang
- School of Mechanical Engineering, Dalian University of Technology, Dalian 116024, China
| | - Zhongyu Feng
- School of Mechanical Engineering, Dalian University of Technology, Dalian 116024, China
| | - Zhenqiang Shi
- CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
| | - Wenjie Yuan
- School of Bioengineering, Dalian University of Technology, Dalian 116024, China
| | - Zhanyu Jing
- School of Bioengineering, Dalian University of Technology, Dalian 116024, China
| | - Lei Zhang
- School of Mechanical Engineering, Dalian University of Technology, Dalian 116024, China
- State Key Laboratory of High-Performance Precision Manufacturing, Dalian University of Technology, Dalian 116024, China
| |
Collapse
|
4
|
Asp ME, Thanh MTH, Dutta S, Comstock JA, Welch RD, Patteson AE. Mechanobiology as a tool for addressing the genotype-to-phenotype problem in microbiology. BIOPHYSICS REVIEWS 2023; 4:021304. [PMID: 38504926 PMCID: PMC10903382 DOI: 10.1063/5.0142121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Accepted: 04/03/2023] [Indexed: 03/21/2024]
Abstract
The central hypothesis of the genotype-phenotype relationship is that the phenotype of a developing organism (i.e., its set of observable attributes) depends on its genome and the environment. However, as we learn more about the genetics and biochemistry of living systems, our understanding does not fully extend to the complex multiscale nature of how cells move, interact, and organize; this gap in understanding is referred to as the genotype-to-phenotype problem. The physics of soft matter sets the background on which living organisms evolved, and the cell environment is a strong determinant of cell phenotype. This inevitably leads to challenges as the full function of many genes, and the diversity of cellular behaviors cannot be assessed without wide screens of environmental conditions. Cellular mechanobiology is an emerging field that provides methodologies to understand how cells integrate chemical and physical environmental stress and signals, and how they are transduced to control cell function. Biofilm forming bacteria represent an attractive model because they are fast growing, genetically malleable and can display sophisticated self-organizing developmental behaviors similar to those found in higher organisms. Here, we propose mechanobiology as a new area of study in prokaryotic systems and describe its potential for unveiling new links between an organism's genome and phenome.
Collapse
|
5
|
Alwine S, Chen C, Shen L, Allcock HR, Siedlecki CA, Xu LC. Crosslinkable fluorophenoxy-substituted poly[bis(octafluoropentoxy) phosphazene] biomaterials with improved antimicrobial effect and hemocompatibility. J Biomed Mater Res B Appl Biomater 2023. [PMID: 36965183 PMCID: PMC10247504 DOI: 10.1002/jbm.b.35252] [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: 08/09/2022] [Revised: 12/23/2022] [Accepted: 03/12/2023] [Indexed: 03/27/2023]
Abstract
Biomaterial-associated microbial infection is one of the most frequent and severe complications associated with the use of biomaterials in medical devices. In previous studies, we developed new fluorinated polyphosphazenes, poly[bis(octafluoropentoxy) phosphazene] (OFP) and crosslinkable OFP (X-OFP), and demonstrated the inhibition of bacterial adhesion and biofilm formation, thereby controlling microbial infection. In this study, two additional fluorinated polyphosphazenes (PPs, defined as LS02 and LS03) with fluorophenoxy-substituted side groups, 4-fluorophenoxy and 4-(trifluoromethyl)phenoxy, respectively, based on X-OFP general structure, were synthesized and applied as coatings on stainless steel. The linkage of fluorophenoxy groups to the P-N backbone of PPs was found to increase the surface stiffness and significantly reduced Staphylococcus bacterial adhesion and inhibited biofilm formation. It also significantly reduced microbial infection compared to OFP, our prior X-OFPs or poly[bis(trifluoroethoxy) phosphazene] (TFE). The biofilm experiments show that the newly synthesized PPs LS02 and LS03 are biofilm free up to 28 days. Plasma coagulation and platelet adhesion/activation experiments also demonstrated that new PPs containing fluorophenoxy side groups are hemocompatible. The development of new crosslinkable fluorinated PPs containing fluorophenoxy-substituted side groups provides a new generation of polyphosphazene materials for medical devices with improved resistance to microbial infections and thrombosis formation.
Collapse
Affiliation(s)
- Shelby Alwine
- Department of Chemistry and Biomolecular Science, Clarkson University, Potsdam, New York, 13699, USA
| | - Chen Chen
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania, 16802, USA
| | - Lihui Shen
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania, 16802, USA
| | - Harry R Allcock
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania, 16802, USA
| | - Christopher A Siedlecki
- Department of Surgery, The Pennsylvania State University, College of Medicine, Hershey, Pennsylvania, 17033, USA
- Department of Biomedical Engineering, The Pennsylvania State University, Hershey, Pennsylvania, 17033, USA
| | - Li-Chong Xu
- Department of Surgery, The Pennsylvania State University, College of Medicine, Hershey, Pennsylvania, 17033, USA
| |
Collapse
|
6
|
Cassin EK, Araujo-Hernandez SA, Baughn DS, Londono MC, Rodriguez DQ, Tseng BS. OprF impacts Pseudomonas aeruginosa biofilm matrix eDNA levels in a nutrient-dependent manner. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.01.530729. [PMID: 36909500 PMCID: PMC10002741 DOI: 10.1101/2023.03.01.530729] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/06/2023]
Abstract
The biofilm matrix is composed of exopolysaccharides, eDNA, membrane vesicles, and proteins. While proteomic analyses have identified numerous matrix proteins, their functions in the biofilm remain understudied compared to the other biofilm components. In the Pseudomonas aeruginosa biofilm, several studies have identified OprF as an abundant matrix protein and, more specifically, as a component of biofilm membrane vesicles. OprF is a major outer membrane porin of P. aeruginosa cells. However, current data describing the effects of OprF in the P. aeruginosa biofilm is limited. Here we identify a nutrient-dependent effect of OprF in static biofilms, whereby Δ oprF cells form significantly less biofilm than wild type when grown in media containing glucose or low sodium chloride concentrations. Interestingly, this biofilm defect occurs during late static biofilm formation and is not dependent on the production of PQS, which is responsible for outer membrane vesicle production. Furthermore, while biofilms lacking OprF contain approximately 60% less total biomass than those of wild type, the number of cells in these two biofilms is equivalent. We demonstrate that P. aeruginosa Δ oprF biofilms with reduced biofilm biomass contain less eDNA than wild-type biofilms. These results suggest that the nutrient-dependent effect of OprF is involved in the maintenance of mature P. aeruginosa biofilms by retaining eDNA in the matrix. IMPORTANCE Many pathogens form biofilms, which are bacterial communities encased in an extracellular matrix that protects them against antibacterial treatments. The roles of several matrix components of the opportunistic pathogen Pseudomonas aeruginosa have been characterized. However, the effects of P. aeruginosa matrix proteins remain understudied and are untapped potential targets for antibiofilm treatments. Here we describe a conditional effect of the abundant matrix protein OprF on late-stage P. aeruginosa biofilms. A Δ oprF strain formed significantly less biofilm in low sodium chloride or with glucose. Interestingly, the defective Δ oprF biofilms did not exhibit fewer resident cells but contained significantly less extracellular DNA (eDNA) than wild type. These results suggest that OprF is involved in matrix eDNA retention in mature biofilms.
Collapse
Affiliation(s)
- Erin K. Cassin
- School of Life Sciences, University of Nevada Las Vegas, Las Vegas, NV, USA
| | | | - Dena S. Baughn
- School of Life Sciences, University of Nevada Las Vegas, Las Vegas, NV, USA
| | - Melissa C. Londono
- School of Life Sciences, University of Nevada Las Vegas, Las Vegas, NV, USA
| | | | - Boo Shan Tseng
- School of Life Sciences, University of Nevada Las Vegas, Las Vegas, NV, USA
- Corresponding author: Boo Shan Tseng ()
| |
Collapse
|
7
|
Material Substrate Physical Properties Control Pseudomonas aeruginosa Biofilm Architecture. mBio 2023; 14:e0351822. [PMID: 36786569 PMCID: PMC10127718 DOI: 10.1128/mbio.03518-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023] Open
Abstract
In the wild, bacteria are most frequently found in the form of multicellular structures called biofilms. Biofilms grow at the surface of abiotic and living materials with wide-ranging mechanical properties. The opportunistic pathogen Pseudomonas aeruginosa forms biofilms on indwelling medical devices and on soft tissues, including burn wounds and the airway mucosa. Despite the critical role of substrates in the foundation of biofilms, we still lack a clear understanding of how material mechanics regulate their architecture and the physiology of resident bacteria. Here, we demonstrate that physical properties of hydrogel material substrates define P. aeruginosa biofilm architecture. We show that hydrogel mesh size regulates twitching motility, a surface exploration mechanism priming biofilms, ultimately controlling the organization of single cells in the multicellular community. The resulting architectural transitions increase P. aeruginosa's tolerance to colistin, a last-resort antibiotic. In addition, mechanical regulation of twitching motility affects P. aeruginosa clonal lineages, so that biofilms are more mixed on relatively denser materials. Our results thereby establish material properties as a factor that dramatically affects biofilm architecture, antibiotic efficacy, and evolution of the resident population. IMPORTANCE The biofilm lifestyle is the most widespread survival strategy in the bacterial world. Pseudomonas aeruginosa biofilms cause chronic infections and are highly recalcitrant to antimicrobials. The genetic requirements allowing P. aeruginosa to grow into biofilms are known, but not the physical stimuli that regulate their formation. Despite colonizing biological tissues, investigations of biofilms on soft materials are limited. In this work, we show that biofilms take unexpected forms when growing on soft substrates. The physical properties of the material shape P. aeruginosa biofilms by regulating surface-specific twitching motility. Physical control of biofilm morphogenesis ultimately influences the resilience of biofilms to antimicrobials, linking physical environment with tolerance to treatment. Altogether, our work established that the physical properties of a surface are a critical environmental regulator of biofilm biogenesis and evolution.
Collapse
|
8
|
Straub H, Zuber F, Eberl L, Maniura-Weber K, Ren Q. In Situ Investigation of Pseudomonas aeruginosa Biofilm Development: Interplay between Flow, Growth Medium, and Mechanical Properties of Substrate. ACS APPLIED MATERIALS & INTERFACES 2023; 15:2781-2791. [PMID: 36601891 DOI: 10.1021/acsami.2c20693] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
To better understand the impact of biomaterial mechanical properties and growth medium on bacterial adhesion and biofilm formation under flow, we investigated the biofilm formation ability of Pseudomonas aeruginosa in different media on polydimethylsiloxane (PDMS) of different stiffness in real time using a microfluidic platform. P. aeruginosa colonization was recorded with optical microscopy and automated image analysis. The bacterial intracellular level of cyclic diguanylate (c-di-GMP), which regulates biofilm formation, was monitored using the transcription of the putative adhesin gene (cdrA) as a proxy. Contrary to the previous supposition, we revealed that PDMS material stiffness within the tested range has negligible impact on biofilm development and biofilm structures, whereas culture media not only influence the kinetics of biofilm development but also affect the biofilm morphology and structure dramatically. Interestingly, magnesium rather than previously reported calcium was identified here to play a decisive role in the formation of dense P. aeruginosa aggregates and high levels of c-di-GMP. These results demonstrate that although short-term adhesion assays bring valuable insight into bacterial and material interactions, long-term evaluations are essential to better predict overall biofilm outcome. The microfluidic system developed here presents a valuable application potential for studying biofilm development in situ. .
Collapse
Affiliation(s)
- Hervé Straub
- Laboratory for Biointerfaces, Empa, Swiss Federal Laboratories for Materials Science and Technology, St. Gallen CH-9014, Switzerland
- Department of Plant and Microbial Biology, University of Zürich, Zürich CH-8008, Switzerland
| | - Flavia Zuber
- Laboratory for Biointerfaces, Empa, Swiss Federal Laboratories for Materials Science and Technology, St. Gallen CH-9014, Switzerland
| | - Leo Eberl
- Department of Plant and Microbial Biology, University of Zürich, Zürich CH-8008, Switzerland
| | - Katharina Maniura-Weber
- Laboratory for Biointerfaces, Empa, Swiss Federal Laboratories for Materials Science and Technology, St. Gallen CH-9014, Switzerland
| | - Qun Ren
- Laboratory for Biointerfaces, Empa, Swiss Federal Laboratories for Materials Science and Technology, St. Gallen CH-9014, Switzerland
| |
Collapse
|
9
|
Wang J, Li P, Wang N, Wang J, Xing D. Antibacterial features of material surface: strong enough to serve as antibiotics? J Mater Chem B 2023; 11:280-302. [PMID: 36533438 DOI: 10.1039/d2tb02139k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Bacteria are small but need big efforts to control. The use of antibiotics not only produces superbugs that are increasingly difficult to inactivate, but also raises environmental concerns with the growing consumption. It is now believed that the antibacterial task can count on some physiochemical features of material surfaces, which can be anti-adhesive or bactericidal without releasing toxicants. It is necessary to evaluate to what extent can we rely on the surface design since the actual application scenarios will need the antibacterial performance to be sharp, robust, environmentally friendly, and long-lasting. Herein, we review the recent laboratory advances that have been classified based on the specific surface features, including hydrophobicity, charge potential, micromorphology, stiffness and viscosity, and photoactivity, and the antibacterial mechanisms of each feature are included to provide a basic rationale for future design. The significance of anti-biofilms is also introduced, given the big role of biofilms in bacteria-caused damage. A perspective on the potential wide application of antibacterial surface features as a substitute or supplement to antibiotics is then discussed. Surface design is no doubt a solution worthy to explore, and future success will be a result of further progress in multiple directions, including mechanism study and material preparation.
Collapse
Affiliation(s)
- Jie Wang
- The Affiliated Hospital of Qingdao University, Qingdao University, Qingdao 266071, China. .,CAS Key Laboratory of Marine Environmental Corrosion and Bio-Fouling, Institute of Oceanology, China Academy of Sciences, Qingdao 266071, China.
| | - Ping Li
- School of Rehabilitation Sciences and Engineering, University of Health and Rehabilitation Sciences, Qingdao 266071, China
| | - Ning Wang
- CAS Key Laboratory of Marine Environmental Corrosion and Bio-Fouling, Institute of Oceanology, China Academy of Sciences, Qingdao 266071, China.
| | - Jing Wang
- CAS Key Laboratory of Marine Environmental Corrosion and Bio-Fouling, Institute of Oceanology, China Academy of Sciences, Qingdao 266071, China.
| | - Dongming Xing
- The Affiliated Hospital of Qingdao University, Qingdao University, Qingdao 266071, China.
| |
Collapse
|
10
|
Bawazir M, Dhall A, Lee J, Kim B, Hwang G. Effect of surface stiffness in initial adhesion of oral microorganisms under various environmental conditions. Colloids Surf B Biointerfaces 2023; 221:112952. [PMID: 36334517 PMCID: PMC11289856 DOI: 10.1016/j.colsurfb.2022.112952] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Revised: 10/11/2022] [Accepted: 10/18/2022] [Indexed: 11/06/2022]
Abstract
Biofilms are three-dimensional structures formed as a result of microorganism's adhesion on a biotic or abiotic surface. Once a biofilm is established, it is onerous to eradicate it or kill the pathogens therein. Thus, targeting the microbial adhesion process, the initial stage of biofilm formation, is a reasonable approach to avoid challenges associated with subsequently formed biofilms. While many properties of interacting material that play significant roles in initial bacterial adhesion have been widely studied, the effect of surface stiffness on bacterial adhesion was relatively underexplored. In this study, we aimed to investigate the effect of surface stiffness on the adhesion of microbial species found in the oral cavity by employing representative oral bacteria, Streptococcus mutans and Streptococcus oralis, and the fungus, Candida albicans. We compared the adhesion behavior of these species alone or in combination toward various surface stiffness (0.06 - 3.01 MPa) by assessing the adhered and planktonic cell numbers at an early (4 h) adhesion stage under various carbon sources and the presence of conditioning film. Our data revealed that in general, a higher amount of microbial cells adhered to softer PDMS surfaces than stiffer ones, which indicates that surface stiffness plays a role in the adhesion of tested species (either single or co-cultured). This pattern was more obvious under sucrose conditions than glucose + fructose conditions. Interestingly, in monospecies, saliva coating did not alter the effect of surface stiffness on S. mutans adhesion while it diminished S. oralis and C. albicans adhesion. However, in the multispecies model, saliva coating rendered the percentage of all adhered microbes to varied PDMS not distinct. The data provide new insights into the role of surface stiffness on microbial mechanosensing and their initial adhesion behavior which may set a scientific foundation for future anti-adhesion strategies.
Collapse
Affiliation(s)
- Marwa Bawazir
- Department of Preventive and Restorative Sciences, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, USA; Restorative Dentistry Department, Faculty of Dentistry, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Atul Dhall
- Department of Preventive and Restorative Sciences, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Jeewoo Lee
- Department of Preventive and Restorative Sciences, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Brett Kim
- Department of Preventive and Restorative Sciences, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Geelsu Hwang
- Department of Preventive and Restorative Sciences, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, USA; Center for Innovation & Precision Dentistry, School of Dental Medicine, School of Engineering and Applied Sciences, University of Pennsylvania, Philadelphia, PA, USA.
| |
Collapse
|
11
|
Campolo A, Pifer R, Shannon P, Crary M. Microbial Adherence to Contact Lenses and Pseudomonas aeruginosa as a Model Organism for Microbial Keratitis. Pathogens 2022; 11:1383. [PMID: 36422634 PMCID: PMC9695309 DOI: 10.3390/pathogens11111383] [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: 10/11/2022] [Revised: 11/11/2022] [Accepted: 11/17/2022] [Indexed: 08/27/2023] Open
Abstract
Microbial keratitis (MK), the infection of the cornea, is a devastating disease and the fifth leading cause of blindness and visual impairment around the world. The overwhelming majority of MK cases are linked to contact lens wear combined with factors which promote infection such as corneal abrasion, an immunocompromised state, improper contact lens use, or failing to routinely disinfect lenses after wear. Contact lens-related MK involves the adherence of microorganisms to the contact lens. Therefore, this review discusses the information currently available regarding the disease pathophysiology, the common types of microorganisms causing MK, physical and organic mechanisms of adhesion, material properties which are involved in adhesion, and current antimicrobial strategies. This review also concludes that Pseudomonas aeruginosa is a model organism for the investigation of contact lens microbial adherence due to its prevalence in MK cases, its extremely robust adhesion, antimicrobial-resistant properties, and the severity of the disease it causes.
Collapse
|
12
|
Xu LC, Siedlecki CA. Surface Texturing and Combinatorial Approaches to Improve Biocompatibility of Implanted Biomaterials. FRONTIERS IN PHYSICS 2022; 10:994438. [PMID: 38250242 PMCID: PMC10798815 DOI: 10.3389/fphy.2022.994438] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2024]
Abstract
Biomaterial associated microbial infection and blood thrombosis are two of the barriers that inhibit the successful use of implantable medical devices in modern healthcare. Modification of surface topography is a promising approach to combat microbial infection and thrombosis without altering bulk material properties necessary for device function and without contributing to bacterial antibiotic resistance. Similarly, the use of other antimicrobial techniques such as grafting poly(ethylene glycol) (PEG) and nitric oxide (NO) release also improve the biocompatibility of biomaterials. In this review, we discuss the development of surface texturing techniques utilizing ordered submicron-size pillars for controlling bacterial adhesion and biofilm formation, and we present combinatorial approaches utilizing surface texturing in combination with poly(ethylene glycol) (PEG) grafting and NO release to improve the biocompatibility of biomaterials. The manuscript also discusses efforts towards understanding the molecular mechanisms of bacterial adhesion responses to the surface texturing and NO releasing biomaterials, focusing on experimental aspects of the approach.
Collapse
Affiliation(s)
- Li-Chong Xu
- Department of Surgery, The Pennsylvania State University, College of Medicine, Hershey, PA 17033
| | - Christopher A. Siedlecki
- Department of Surgery, The Pennsylvania State University, College of Medicine, Hershey, PA 17033
- Department of Biomedical Engineering, The Pennsylvania State University, College of Medicine, Hershey, PA 17033
| |
Collapse
|
13
|
Drebezghova V, Hakil F, Grimaud R, Gojzewski H, Vancso GJ, Nardin C. Initial bacterial retention on polydimethylsiloxane of various stiffnesses: The relevance of modulus (mis)match. Colloids Surf B Biointerfaces 2022. [DOI: 10.1016/j.colsurfb.2022.112709] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
|
14
|
Qin S, Xiao W, Zhou C, Pu Q, Deng X, Lan L, Liang H, Song X, Wu M. Pseudomonas aeruginosa: pathogenesis, virulence factors, antibiotic resistance, interaction with host, technology advances and emerging therapeutics. Signal Transduct Target Ther 2022; 7:199. [PMID: 35752612 PMCID: PMC9233671 DOI: 10.1038/s41392-022-01056-1] [Citation(s) in RCA: 281] [Impact Index Per Article: 140.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 06/04/2022] [Accepted: 06/08/2022] [Indexed: 02/05/2023] Open
Abstract
Pseudomonas aeruginosa (P. aeruginosa) is a Gram-negative opportunistic pathogen that infects patients with cystic fibrosis, burn wounds, immunodeficiency, chronic obstructive pulmonary disorder (COPD), cancer, and severe infection requiring ventilation, such as COVID-19. P. aeruginosa is also a widely-used model bacterium for all biological areas. In addition to continued, intense efforts in understanding bacterial pathogenesis of P. aeruginosa including virulence factors (LPS, quorum sensing, two-component systems, 6 type secretion systems, outer membrane vesicles (OMVs), CRISPR-Cas and their regulation), rapid progress has been made in further studying host-pathogen interaction, particularly host immune networks involving autophagy, inflammasome, non-coding RNAs, cGAS, etc. Furthermore, numerous technologic advances, such as bioinformatics, metabolomics, scRNA-seq, nanoparticles, drug screening, and phage therapy, have been used to improve our understanding of P. aeruginosa pathogenesis and host defense. Nevertheless, much remains to be uncovered about interactions between P. aeruginosa and host immune responses, including mechanisms of drug resistance by known or unannotated bacterial virulence factors as well as mammalian cell signaling pathways. The widespread use of antibiotics and the slow development of effective antimicrobials present daunting challenges and necessitate new theoretical and practical platforms to screen and develop mechanism-tested novel drugs to treat intractable infections, especially those caused by multi-drug resistance strains. Benefited from has advancing in research tools and technology, dissecting this pathogen's feature has entered into molecular and mechanistic details as well as dynamic and holistic views. Herein, we comprehensively review the progress and discuss the current status of P. aeruginosa biophysical traits, behaviors, virulence factors, invasive regulators, and host defense patterns against its infection, which point out new directions for future investigation and add to the design of novel and/or alternative therapeutics to combat this clinically significant pathogen.
Collapse
Affiliation(s)
- Shugang Qin
- Department of Critical Care Medicine, Frontiers Science Center for Disease-related Molecular Network, State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu, China
| | - Wen Xiao
- Department of Critical Care Medicine, Frontiers Science Center for Disease-related Molecular Network, State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu, China
| | - Chuanmin Zhou
- State Key Laboratory of Virology, School of Public Health, Wuhan University, Wuhan, 430071, P.R. China
- Department of Biomedical Sciences, School of Medicine and Health Sciences, University of North Dakota, Grand Forks, ND, 58203, USA
| | - Qinqin Pu
- Department of Biomedical Sciences, School of Medicine and Health Sciences, University of North Dakota, Grand Forks, ND, 58203, USA
| | - Xin Deng
- Department of Biomedical Sciences, City University of Hong Kong, Hong Kong, People's Republic of China
| | - Lefu Lan
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, 201203, China
| | - Haihua Liang
- College of Life Sciences, Northwest University, Xi'an, ShaanXi, 710069, China
| | - Xiangrong Song
- Department of Critical Care Medicine, Frontiers Science Center for Disease-related Molecular Network, State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu, China.
| | - Min Wu
- Department of Critical Care Medicine, Frontiers Science Center for Disease-related Molecular Network, State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu, China.
- Department of Biomedical Sciences, School of Medicine and Health Sciences, University of North Dakota, Grand Forks, ND, 58203, USA.
| |
Collapse
|
15
|
Santore MM. Interplay of physico-chemical and mechanical bacteria-surface interactions with transport processes controls early biofilm growth: A review. Adv Colloid Interface Sci 2022; 304:102665. [PMID: 35468355 DOI: 10.1016/j.cis.2022.102665] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Revised: 04/03/2022] [Accepted: 04/04/2022] [Indexed: 11/01/2022]
Abstract
Biofilms initiate when bacteria encounter and are retained on surfaces. The surface orchestrates biofilm growth through direct physico-chemical and mechanical interactions with different structures on bacterial cells and, in turn, through its influence on cell-cell interactions. Individual cells respond directly to a surface through mechanical or chemical means, initiating "surface sensing" pathways that regulate gene expression, for instance producing extra cellular matrix or altering phenotypes. The surface can also physically direct the evolving colony morphology as cells divide and grow. In either case, the physico-chemistry of the surface influences cells and cell communities through mechanisms that involve additional factors. For instance the numbers of cells arriving on a surface from solution relative to the generation of new cells by division depends on adhesion and transport kinetics, affecting early colony density and composition. Separately, the forces experienced by adhering cells depend on hydrodynamics, gravity, and the relative stiffnesses and viscoelasticity of the cells and substrate materials, affecting mechanosensing pathways. Physical chemistry and surface functionality, along with interfacial mechanics also influence cell-surface friction and control colony morphology, in particular 2D and 3D shape. This review focuses on the current understanding of the mechanisms in which physico-chemical interactions, deriving from surface functionality, impact individual cells and cell community behavior through their coupling with other interfacial processes.
Collapse
|
16
|
Pseudomonas aeruginosa Initiates a Rapid and Specific Transcriptional Response during Surface Attachment. J Bacteriol 2022; 204:e0008622. [PMID: 35467391 PMCID: PMC9112911 DOI: 10.1128/jb.00086-22] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Chronic biofilm infections by Pseudomonas aeruginosa are a major contributor to the morbidity and mortality of patients. The formation of multicellular bacterial aggregates, called biofilms, is associated with increased resistance to antimicrobials and immune clearance and the persistence of infections. Biofilm formation is dependent on bacterial cell attachment to surfaces, and therefore, attachment plays a key role in chronic infections. We hypothesized that bacteria sense various surfaces and initiate a rapid, specific response to increase adhesion and establish biofilms. RNA sequencing (RNA-Seq) analysis identified transcriptional changes of adherent cells during initial attachment, identifying the bacterial response to an abiotic surface over a 1-h period. Subsequent screens investigating the most highly regulated genes in surface attachment identified 4 genes, pfpI, phnA, leuD, and moaE, all of which have roles in both metabolism and biofilm formation. In addition, the transcriptional responses to several different medically relevant abiotic surfaces were compared after initial attachment. Surprisingly, there was a specific transcriptional response to each surface, with very few genes being regulated in response to surfaces in general. We identified a set of 20 genes that were differentially expressed across all three surfaces, many of which have metabolic functions, including molybdopterin cofactor biosynthesis and nitrogen metabolism. This study has advanced the understanding of the kinetics and specificity of bacterial transcriptional responses to surfaces and suggests that metabolic cues are important signals during the transition from a planktonic to a biofilm lifestyle. IMPORTANCE Bacterial biofilms are a significant concern in many aspects of life, including chronic infections of airways, wounds, and indwelling medical devices; biofouling of industrial surfaces relevant for food production and marine surfaces; and nosocomial infections. The effects of understanding surface adhesion could impact many areas of life. This study utilized emerging technology in a novel approach to address a key step in bacterial biofilm development. These findings have elucidated both conserved and surface-specific responses to several disease-relevant abiotic surfaces. Future work will expand on this report to identify mechanisms of biofilm initiation with the aim of identifying bacterial factors that could be targeted to prevent biofilms.
Collapse
|
17
|
Asp ME, Ho Thanh MT, Germann DA, Carroll RJ, Franceski A, Welch RD, Gopinath A, Patteson AE. Spreading rates of bacterial colonies depend on substrate stiffness and permeability. PNAS NEXUS 2022; 1:pgac025. [PMID: 36712798 PMCID: PMC9802340 DOI: 10.1093/pnasnexus/pgac025] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 01/25/2022] [Accepted: 03/09/2022] [Indexed: 02/01/2023]
Abstract
The ability of bacteria to colonize and grow on different surfaces is an essential process for biofilm development. Here, we report the use of synthetic hydrogels with tunable stiffness and porosity to assess physical effects of the substrate on biofilm development. Using time-lapse microscopy to track the growth of expanding Serratia marcescens colonies, we find that biofilm colony growth can increase with increasing substrate stiffness, unlike what is found on traditional agar substrates. Using traction force microscopy-based techniques, we find that biofilms exert transient stresses correlated over length scales much larger than a single bacterium, and that the magnitude of these forces also increases with increasing substrate stiffness. Our results are consistent with a model of biofilm development in which the interplay between osmotic pressure arising from the biofilm and the poroelastic response of the underlying substrate controls biofilm growth and morphology.
Collapse
Affiliation(s)
- Merrill E Asp
- Physics Department, Syracuse University, Syracuse, NY 13244, USA,BioInspired Institute, Syracuse University, Syracuse, NY 13244, USA
| | - Minh-Tri Ho Thanh
- Physics Department, Syracuse University, Syracuse, NY 13244, USA,BioInspired Institute, Syracuse University, Syracuse, NY 13244, USA
| | - Danielle A Germann
- Physics Department, Syracuse University, Syracuse, NY 13244, USA,BioInspired Institute, Syracuse University, Syracuse, NY 13244, USA
| | - Robert J Carroll
- Physics Department, Syracuse University, Syracuse, NY 13244, USA,BioInspired Institute, Syracuse University, Syracuse, NY 13244, USA
| | - Alana Franceski
- BioInspired Institute, Syracuse University, Syracuse, NY 13244, USA,Biology Department, Syracuse University, Syracuse, NY 13244, USA
| | - Roy D Welch
- BioInspired Institute, Syracuse University, Syracuse, NY 13244, USA,Biology Department, Syracuse University, Syracuse, NY 13244, USA
| | - Arvind Gopinath
- Department of Bioengineering, University of California, Merced, Merced, CA 95343, USA,Health Sciences Research Institute, University of California, Merced, Merced, CA 95343, USA
| | | |
Collapse
|
18
|
Patteson AE, Asp ME, Janmey PA. Materials science and mechanosensitivity of living matter. APPLIED PHYSICS REVIEWS 2022; 9:011320. [PMID: 35392267 PMCID: PMC8969880 DOI: 10.1063/5.0071648] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Accepted: 02/08/2022] [Indexed: 06/14/2023]
Abstract
Living systems are composed of molecules that are synthesized by cells that use energy sources within their surroundings to create fascinating materials that have mechanical properties optimized for their biological function. Their functionality is a ubiquitous aspect of our lives. We use wood to construct furniture, bacterial colonies to modify the texture of dairy products and other foods, intestines as violin strings, bladders in bagpipes, and so on. The mechanical properties of these biological materials differ from those of other simpler synthetic elastomers, glasses, and crystals. Reproducing their mechanical properties synthetically or from first principles is still often unattainable. The challenge is that biomaterials often exist far from equilibrium, either in a kinetically arrested state or in an energy consuming active state that is not yet possible to reproduce de novo. Also, the design principles that form biological materials often result in nonlinear responses of stress to strain, or force to displacement, and theoretical models to explain these nonlinear effects are in relatively early stages of development compared to the predictive models for rubberlike elastomers or metals. In this Review, we summarize some of the most common and striking mechanical features of biological materials and make comparisons among animal, plant, fungal, and bacterial systems. We also summarize some of the mechanisms by which living systems develop forces that shape biological matter and examine newly discovered mechanisms by which cells sense and respond to the forces they generate themselves, which are resisted by their environment, or that are exerted upon them by their environment. Within this framework, we discuss examples of how physical methods are being applied to cell biology and bioengineering.
Collapse
Affiliation(s)
- Alison E. Patteson
- Physics Department and BioInspired Institute, Syracuse University, Syracuse NY, 13244, USA
| | - Merrill E. Asp
- Physics Department and BioInspired Institute, Syracuse University, Syracuse NY, 13244, USA
| | - Paul A. Janmey
- Institute for Medicine and Engineering and Departments of Physiology and Physics & Astronomy, University of Pennsylvania, Philadelphia PA, 19104, USA
| |
Collapse
|
19
|
Igler C, Huisman JS, Siedentop B, Bonhoeffer S, Lehtinen S. Plasmid co-infection: linking biological mechanisms to ecological and evolutionary dynamics. Philos Trans R Soc Lond B Biol Sci 2022; 377:20200478. [PMID: 34839701 PMCID: PMC8628072 DOI: 10.1098/rstb.2020.0478] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Accepted: 07/09/2021] [Indexed: 12/27/2022] Open
Abstract
As infectious agents of bacteria and vehicles of horizontal gene transfer, plasmids play a key role in bacterial ecology and evolution. Plasmid dynamics are shaped not only by plasmid-host interactions but also by ecological interactions between plasmid variants. These interactions are complex: plasmids can co-infect the same cell and the consequences for the co-resident plasmid can be either beneficial or detrimental. Many of the biological processes that govern plasmid co-infection-from systems that exclude infection by other plasmids to interactions in the regulation of plasmid copy number-are well characterized at a mechanistic level. Modelling plays a central role in translating such mechanistic insights into predictions about plasmid dynamics and the impact of these dynamics on bacterial evolution. Theoretical work in evolutionary epidemiology has shown that formulating models of co-infection is not trivial, as some modelling choices can introduce unintended ecological assumptions. Here, we review how the biological processes that govern co-infection can be represented in a mathematical model, discuss potential modelling pitfalls, and analyse this model to provide general insights into how co-infection impacts ecological and evolutionary outcomes. In particular, we demonstrate how beneficial and detrimental effects of co-infection give rise to frequency-dependent selection on plasmid variants. This article is part of the theme issue 'The secret lives of microbial mobile genetic elements'.
Collapse
Affiliation(s)
- Claudia Igler
- Institute of Integrative Biology, Department of Environmental Systems Science, ETH Zürich, Zurich, Switzerland
| | - Jana S. Huisman
- Institute of Integrative Biology, Department of Environmental Systems Science, ETH Zürich, Zurich, Switzerland
- Swiss Institute of Bioinformatics, Lausanne, Switzerland
| | - Berit Siedentop
- Institute of Integrative Biology, Department of Environmental Systems Science, ETH Zürich, Zurich, Switzerland
| | - Sebastian Bonhoeffer
- Institute of Integrative Biology, Department of Environmental Systems Science, ETH Zürich, Zurich, Switzerland
| | - Sonja Lehtinen
- Institute of Integrative Biology, Department of Environmental Systems Science, ETH Zürich, Zurich, Switzerland
| |
Collapse
|
20
|
Nasri N, Rusli A, Teramoto N, Jaafar M, Ku Ishak KM, Shafiq MD, Abdul Hamid ZA. Past and Current Progress in the Development of Antiviral/Antimicrobial Polymer Coating towards COVID-19 Prevention: A Review. Polymers (Basel) 2021; 13:4234. [PMID: 34883737 PMCID: PMC8659939 DOI: 10.3390/polym13234234] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Revised: 11/04/2021] [Accepted: 11/08/2021] [Indexed: 01/10/2023] Open
Abstract
The astonishing outbreak of SARS-CoV-2 coronavirus, known as COVID-19, has attracted numerous research interests, particularly regarding fabricating antimicrobial surface coatings. This initiative is aimed at overcoming and minimizing viral and bacterial transmission to the human. When contaminated droplets from an infected individual land onto common surfaces, SARS-CoV-2 coronavirus is able to survive on various surfaces for up to 9 days. Thus, the possibility of virus transmission increases after touching or being in contact with contaminated surfaces. Herein, we aim to provide overviews of various types of antiviral and antimicrobial coating agents, such as antimicrobial polymer-based coating, metal-based coating, functional nanomaterial, and nanocomposite-based coating. The action mode for each type of antimicrobial agent against pathogens is elaborated. In addition, surface properties of the designed antiviral and antimicrobial polymer coating with their influencing factors are discussed in this review. This paper also exhibits several techniques on surface modification to improve surface properties. Various developed research on the development of antiviral/antimicrobial polymer coating to curb the COVID-19 pandemic are also presented in this review.
Collapse
Affiliation(s)
- Nazihah Nasri
- School of Materials & Mineral Resources Engineering, Universiti Sains Malaysia, Engineering Campus, Nibong Tebal 14300, Pulau Pinang, Malaysia; (N.N.); (A.R.); (M.J.); (K.M.K.I.); (M.D.S.)
| | - Arjulizan Rusli
- School of Materials & Mineral Resources Engineering, Universiti Sains Malaysia, Engineering Campus, Nibong Tebal 14300, Pulau Pinang, Malaysia; (N.N.); (A.R.); (M.J.); (K.M.K.I.); (M.D.S.)
| | - Naozumi Teramoto
- Department of Applied Chemistry, Faculty of Engineering, Chiba Institute of Technology, 2-17-1 Tsudanuma, Narashino 275-0016, Chiba, Japan;
| | - Mariatti Jaafar
- School of Materials & Mineral Resources Engineering, Universiti Sains Malaysia, Engineering Campus, Nibong Tebal 14300, Pulau Pinang, Malaysia; (N.N.); (A.R.); (M.J.); (K.M.K.I.); (M.D.S.)
| | - Ku Marsilla Ku Ishak
- School of Materials & Mineral Resources Engineering, Universiti Sains Malaysia, Engineering Campus, Nibong Tebal 14300, Pulau Pinang, Malaysia; (N.N.); (A.R.); (M.J.); (K.M.K.I.); (M.D.S.)
| | - Mohamad Danial Shafiq
- School of Materials & Mineral Resources Engineering, Universiti Sains Malaysia, Engineering Campus, Nibong Tebal 14300, Pulau Pinang, Malaysia; (N.N.); (A.R.); (M.J.); (K.M.K.I.); (M.D.S.)
| | - Zuratul Ain Abdul Hamid
- School of Materials & Mineral Resources Engineering, Universiti Sains Malaysia, Engineering Campus, Nibong Tebal 14300, Pulau Pinang, Malaysia; (N.N.); (A.R.); (M.J.); (K.M.K.I.); (M.D.S.)
| |
Collapse
|
21
|
Sindeldecker D, Stoodley P. The many antibiotic resistance and tolerance strategies of Pseudomonas aeruginosa. Biofilm 2021; 3:100056. [PMID: 34471871 PMCID: PMC8387898 DOI: 10.1016/j.bioflm.2021.100056] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Revised: 08/17/2021] [Accepted: 08/18/2021] [Indexed: 12/15/2022] Open
Abstract
Pseudomonas aeruginosa is a bacterial pathogen associated with a wide range of infections and utilizes several strategies to establish and maintain infection including biofilm production, multidrug resistance, and antibiotic tolerance. Multidrug resistance in P. aeruginosa, as well as in all other bacterial pathogens, is a growing concern. Aminoglycoside resistance, in particular, is a major concern in P. aeruginosa infections and must be better understood in order to maintain effective clinical treatment. In this review, the various antibiotic resistance and tolerance mechanisms of Pseudomonas are explored including: classic mutation driven resistance, adaptive resistance, persister cells, small colony variants, phoenix colonies, and biofilms. It is important to further characterize each of these phenotypes and continue to evaluate antibiotic surviving isolates for novel driving mechanisms, so that we are better prepared to combat the rising number of recurrent and recalcitrant infections.
Collapse
Affiliation(s)
- Devin Sindeldecker
- Department of Microbial Infection and Immunity, The Ohio State University, Columbus, OH, USA
- Biomedical Sciences Graduate Program, The Ohio State University, Columbus, OH, USA
| | - Paul Stoodley
- Department of Microbial Infection and Immunity, The Ohio State University, Columbus, OH, USA
- Department of Orthopaedics, The Ohio State University, Columbus, OH, USA
- National Center for Advanced Tribology at Southampton (nCATS), Mechanical Engineering, University of Southampton, Southampton, UK
| |
Collapse
|
22
|
Surface Modification to Modulate Microbial Biofilms-Applications in Dental Medicine. MATERIALS 2021; 14:ma14226994. [PMID: 34832390 PMCID: PMC8625127 DOI: 10.3390/ma14226994] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Revised: 11/12/2021] [Accepted: 11/12/2021] [Indexed: 12/21/2022]
Abstract
Recent progress in materials science and nanotechnology has led to the development of advanced materials with multifunctional properties. Dental medicine has benefited from the design of such materials and coatings in providing patients with tailored implants and improved materials for restorative and functional use. Such materials and coatings allow for better acceptance by the host body, promote successful implantation and determine a reduced inflammatory response after contact with the materials. Since numerous dental pathologies are influenced by the presence and activity of some pathogenic microorganisms, novel materials are needed to overcome this challenge as well. This paper aimed to reveal and discuss the most recent and innovative progress made in the field of materials surface modification in terms of microbial attachment inhibition and biofilm formation, with a direct impact on dental medicine.
Collapse
|
23
|
Exploration of the Pharmacodynamics for Pseudomonas aeruginosa Biofilm Eradication by Tobramycin. Antimicrob Agents Chemother 2021; 66:e0137121. [PMID: 34694882 DOI: 10.1128/aac.01371-21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Pseudomonas aeruginosa is a Gram-negative, opportunistic pathogen which is involved in numerous infections. It is of growing concern within the field of antibiotic resistant and tolerance and often exhibits multi-drug resistance. Previous studies have shown the emergence of antibiotic resistant and tolerant variants within the zone of clearance of a biofilm lawn after exposure to aminoglycosides. As concerning as the tolerant variant emergence is, there was also a zone of killing (ZOK) immediately surrounding the antibiotic source from which no detectable bacteria emerged or were cultured. In this study, the ZOK was analyzed using both in vitro and in silico methods to determine if there was a consistent antibiotic concentration versus time constraint (area under the curve, (AUC)) which is able to completely kill all bacteria in the lawn biofilms in our in vitro model. Our studies revealed that by achieving an average AUC of 4,372.5 μg*hr/mL, complete eradication of biofilms grown on both agar and hydroxyapatite was possible. These findings show that appropriate antibiotic concentrations and treatment duration may be able to treat antibiotic resistant and tolerant biofilm infections.
Collapse
|
24
|
Lee SW, Carnicelli J, Getya D, Gitsov I, Phillips KS, Ren D. Biofilm Removal by Reversible Shape Recovery of the Substrate. ACS APPLIED MATERIALS & INTERFACES 2021; 13:17174-17182. [PMID: 33822590 PMCID: PMC8153534 DOI: 10.1021/acsami.0c20697] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Accepted: 03/23/2021] [Indexed: 05/21/2023]
Abstract
Bacteria can colonize essentially any surface and form antibiotic resistant biofilms, which are multicellular structures embedded in an extracellular matrix secreted by the attached cells. To develop better biofilm control technologies, we recently demonstrated that mature biofilms can be effectively removed through on-demand shape recovery of a shape memory polymer (SMP) composed of tert-butyl acrylate (tBA). It was further demonstrated that such a dynamic substratum can sensitize the detached biofilm cells to antibiotics. However, this SMP can undergo shape change only once, limiting its application in long-term biofilm control. This motivated the present study, which aimed to prove the concept that biofilm can be effectively removed by repeated on-demand shape recovery. Reversible shape memory polymers (rSMPs) containing poly(ε-caprolactone) diisocyanatoethyl dimethacrylate (PCLDIMA) of varying molecular masses and butyl acrylate (BA) as a linker were synthesized by using benzoyl peroxide (BPO) as a thermal initiator. By comparison of several combinations of PCLDIMA of different molecular masses, a 2:1 weight ratio mixture of 2000 and 15000 g/mol PCLDIMA was the most promising because it had a shape transition (at 36.7 °C) close to body temperature. The synthesized rSMP demonstrated good reversible shape recovery and up to 94.3 ± 1.0% removal of 48 h Pseudomonas aeruginosa PAO1 biofilm cells after three consecutive shape recovery cycles. Additionally, the detached biofilm cells were found to be 5.0 ± 1.2 times more susceptible to 50 μg/mL tobramycin than the static control.
Collapse
Affiliation(s)
- Sang Won Lee
- Department
of Biomedical and Chemical Engineering, Syracuse University, Syracuse, New York 13244, United States
| | - Joseph Carnicelli
- Department
of Biomedical and Chemical Engineering, Syracuse University, Syracuse, New York 13244, United States
| | - Dariya Getya
- Department
of Chemistry, State University of New York
- College of Environmental Science and Forestry, Syracuse, New York 13210, United States
- The
Michael M. Szwarc Polymer Research Institute, Syracuse, New York 13210, United States
| | - Ivan Gitsov
- Department
of Chemistry, State University of New York
- College of Environmental Science and Forestry, Syracuse, New York 13210, United States
- The
Michael M. Szwarc Polymer Research Institute, Syracuse, New York 13210, United States
| | - K. Scott Phillips
- Center
for Devices and Radiological Health, Office of Science and Engineering
Laboratories, Division of Biology, Chemistry, and Materials Science, United States Food and Drug Administration, Silver Spring, Maryland 20993, United States
| | - Dacheng Ren
- Department
of Biomedical and Chemical Engineering, Syracuse University, Syracuse, New York 13244, United States
- Department
of Civil and Environmental Engineering, Syracuse University, Syracuse, New York 13244, United States
- Department
of Biology, Syracuse University, Syracuse, New York 13244, United States
- (D.R.) Phone +1-315-443-4409. Fax +1-315-443-9175. Email
| |
Collapse
|
25
|
Jurado-Martín I, Sainz-Mejías M, McClean S. Pseudomonas aeruginosa: An Audacious Pathogen with an Adaptable Arsenal of Virulence Factors. Int J Mol Sci 2021; 22:3128. [PMID: 33803907 PMCID: PMC8003266 DOI: 10.3390/ijms22063128] [Citation(s) in RCA: 236] [Impact Index Per Article: 78.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Revised: 03/16/2021] [Accepted: 03/16/2021] [Indexed: 12/13/2022] Open
Abstract
Pseudomonas aeruginosa is a dominant pathogen in people with cystic fibrosis (CF) contributing to morbidity and mortality. Its tremendous ability to adapt greatly facilitates its capacity to cause chronic infections. The adaptability and flexibility of the pathogen are afforded by the extensive number of virulence factors it has at its disposal, providing P. aeruginosa with the facility to tailor its response against the different stressors in the environment. A deep understanding of these virulence mechanisms is crucial for the design of therapeutic strategies and vaccines against this multi-resistant pathogen. Therefore, this review describes the main virulence factors of P. aeruginosa and the adaptations it undergoes to persist in hostile environments such as the CF respiratory tract. The very large P. aeruginosa genome (5 to 7 MB) contributes considerably to its adaptive capacity; consequently, genomic studies have provided significant insights into elucidating P. aeruginosa evolution and its interactions with the host throughout the course of infection.
Collapse
Affiliation(s)
| | | | - Siobhán McClean
- School of Biomolecular and Biomedical Sciences, University College Dublin, Belfield, Dublin 4 D04 V1W8, Ireland; (I.J.-M.); (M.S.-M.)
| |
Collapse
|
26
|
Zheng S, Bawazir M, Dhall A, Kim HE, He L, Heo J, Hwang G. Implication of Surface Properties, Bacterial Motility, and Hydrodynamic Conditions on Bacterial Surface Sensing and Their Initial Adhesion. Front Bioeng Biotechnol 2021; 9:643722. [PMID: 33644027 PMCID: PMC7907602 DOI: 10.3389/fbioe.2021.643722] [Citation(s) in RCA: 213] [Impact Index Per Article: 71.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Accepted: 01/25/2021] [Indexed: 12/29/2022] Open
Abstract
Biofilms are structured microbial communities attached to surfaces, which play a significant role in the persistence of biofoulings in both medical and industrial settings. Bacteria in biofilms are mostly embedded in a complex matrix comprised of extracellular polymeric substances that provide mechanical stability and protection against environmental adversities. Once the biofilm is matured, it becomes extremely difficult to kill bacteria or mechanically remove biofilms from solid surfaces. Therefore, interrupting the bacterial surface sensing mechanism and subsequent initial binding process of bacteria to surfaces is essential to effectively prevent biofilm-associated problems. Noting that the process of bacterial adhesion is influenced by many factors, including material surface properties, this review summarizes recent works dedicated to understanding the influences of surface charge, surface wettability, roughness, topography, stiffness, and combination of properties on bacterial adhesion. This review also highlights other factors that are often neglected in bacterial adhesion studies such as bacterial motility and the effect of hydrodynamic flow. Lastly, the present review features recent innovations in nanotechnology-based antifouling systems to engineer new concepts of antibiofilm surfaces.
Collapse
Affiliation(s)
- Sherry Zheng
- Department of Preventive & Restorative Sciences, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Marwa Bawazir
- Department of Preventive & Restorative Sciences, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Atul Dhall
- Department of Preventive & Restorative Sciences, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Hye-Eun Kim
- Department of Preventive & Restorative Sciences, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Le He
- Department of Preventive & Restorative Sciences, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Joseph Heo
- Department of Preventive & Restorative Sciences, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Geelsu Hwang
- Department of Preventive & Restorative Sciences, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, United States
- Center for Innovation & Precision Dentistry, School of Dental Medicine, School of Engineering and Applied Sciences, University of Pennsylvania, Philadelphia, PA, United States
| |
Collapse
|
27
|
Behzadi P, Baráth Z, Gajdács M. It's Not Easy Being Green: A Narrative Review on the Microbiology, Virulence and Therapeutic Prospects of Multidrug-Resistant Pseudomonas aeruginosa. Antibiotics (Basel) 2021; 10:42. [PMID: 33406652 PMCID: PMC7823828 DOI: 10.3390/antibiotics10010042] [Citation(s) in RCA: 109] [Impact Index Per Article: 36.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Revised: 12/29/2020] [Accepted: 12/31/2020] [Indexed: 12/11/2022] Open
Abstract
Pseudomonas aeruginosa is the most frequent cause of infection among non-fermenting Gram-negative bacteria, predominantly affecting immunocompromised patients, but its pathogenic role should not be disregarded in immunocompetent patients. These pathogens present a concerning therapeutic challenge to clinicians, both in community and in hospital settings, due to their increasing prevalence of resistance, and this may lead to prolonged therapy, sequelae, and excess mortality in the affected patient population. The resistance mechanisms of P. aeruginosa may be classified into intrinsic and acquired resistance mechanisms. These mechanisms lead to occurrence of resistant strains against important antibiotics-relevant in the treatment of P. aeruginosa infections-such as β-lactams, quinolones, aminoglycosides, and colistin. The occurrence of a specific resistotype of P. aeruginosa, namely the emergence of carbapenem-resistant but cephalosporin-susceptible (Car-R/Ceph-S) strains, has received substantial attention from clinical microbiologists and infection control specialists; nevertheless, the available literature on this topic is still scarce. The aim of this present review paper is to provide a concise summary on the adaptability, virulence, and antibiotic resistance of P. aeruginosa to a readership of basic scientists and clinicians.
Collapse
Affiliation(s)
- Payam Behzadi
- Department of Microbiology, College of Basic Sciences, Shahr-e-Qods Branch, Islamic Azad University, Tehran 37541-374, Iran;
| | - Zoltán Baráth
- Department of Prosthodontics, Faculty of Dentistry, University of Szeged, Tisza Lajos körút 62-64, 6720 Szeged, Hungary;
| | - Márió Gajdács
- Institute of Medical Microbiology, Faculty of Medicine, Semmelweis University, 1089 Budapest, Hungary
- Department of Pharmacodynamics and Biopharmacy, Faculty of Pharmacy, University of Szeged, 6720 Szeged, Hungary
| |
Collapse
|
28
|
Blacutt J, Lan Z, Cosgriff-Hernandez EM, Gordon VD. Quantitative confocal microscopy and calibration for measuring differences in cyclic-di-GMP signalling by bacteria on biomedical hydrogels. ROYAL SOCIETY OPEN SCIENCE 2021; 8:201453. [PMID: 33614081 PMCID: PMC7890475 DOI: 10.1098/rsos.201453] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Accepted: 11/30/2020] [Indexed: 06/12/2023]
Abstract
The growth of bacterial biofilms on implanted medical devices causes harmful infections and device failure. Biofilm development initiates when bacteria attach to and sense a surface. For the common nosocomial pathogen Pseudomonas aeruginosa and many others, the transition to the biofilm phenotype is controlled by the intracellular signal and second messenger cyclic-di-GMP (c-di-GMP). It is not known how biomedical materials might be adjusted to impede c-di-GMP signalling, and there are few extant methods for conducting such studies. Here, we develop such a method. We allowed P. aeruginosa to attach to the surfaces of poly(ethylene glycol) diacrylate (PEGDA) hydrogels. These bacteria contained a plasmid for a green fluorescent protein (GFP) reporter for c-di-GMP. We used laser-scanning confocal microscopy to measure the dynamics of the GFP reporter for 3 h, beginning 1 h after introducing bacteria to the hydrogel. We controlled for the effects of changes in bacterial metabolism using a promoterless plasmid for GFP, and for the effects of light passing through different hydrogels being differently attenuated by using fluorescent plastic beads as 'standard candles' for calibration. We demonstrate that this method can measure statistically significant differences in c-di-GMP signalling associated with different PEGDA gel types and with the surface-exposed protein PilY1.
Collapse
Affiliation(s)
- Jacob Blacutt
- Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, TX, USA
- Center for Nonlinear Dynamics, The University of Texas at Austin, Austin, TX, USA
| | - Ziyang Lan
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX, USA
| | | | - Vernita D. Gordon
- Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, TX, USA
- Center for Nonlinear Dynamics, The University of Texas at Austin, Austin, TX, USA
- Department of Physics, The University of Texas at Austin, Austin, TX, USA
- LaMontagne Center for Infectious Disease, The University of Texas at Austin, Austin, TX, USA
| |
Collapse
|
29
|
Carabelli A, Isgró M, Sanni O, Figueredo GP, Winkler DA, Burroughs L, Blok AJ, Dubern JF, Pappalardo F, Hook AL, Williams P, Alexander MR. Single-Cell Tracking on Polymer Microarrays Reveals the Impact of Surface Chemistry on Pseudomonas aeruginosa Twitching Speed and Biofilm Development. ACS APPLIED BIO MATERIALS 2020; 3:8471-8480. [PMID: 34308271 PMCID: PMC8291582 DOI: 10.1021/acsabm.0c00849] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Accepted: 10/22/2020] [Indexed: 12/02/2022]
Abstract
Bacterial biofilms exhibit up to 1000 times greater resistance to antibiotic or host immune clearance than planktonic cells. Pseudomonas aeruginosa produces retractable type IV pili (T4P) that facilitate twitching motility on surfaces. The deployment of pili is one of the first responses of bacteria to surface interactions and because of their ability to contribute to cell surface adhesion and biofilm formation, this has relevance to medical device-associated infections. While polymer chemistry is known to influence biofilm development, its impact on twitching motility is not understood. Here, we combine a polymer microarray format with time-lapse automated microscopy to simultaneously assess P. aeruginosa twitching motility on 30 different methacrylate/acrylate polymers over 60 min post inoculation using a high-throughput system. During this critical initial period where the decision to form a biofilm is thought to occur, similar numbers of bacterial cells accumulate on each polymer. Twitching motility is observed on all polymers irrespective of their chemistry and physical surface properties, in contrast to the differential biofilm formation noted after 24 h of incubation. However, on the microarray polymers, P. aeruginosa cells twitch at significantly different speeds, ranging from 5 to ∼13 nm/s, associated with crawling or walking and are distinguishable from the different cell surface tilt angles observed. Chemometric analysis using partial least-squares (PLS) regression identifies correlations between surface chemistry, as measured by time-of-flight secondary ion mass spectrometry (ToF-SIMS), and both biofilm formation and single-cell twitching speed. The relationships between surface chemistry and these two responses are different for each process. There is no correlation between polymer surface stiffness and roughness as determined by atomic force measurement (AFM), or water contact angle (WCA), and twitching speed or biofilm formation. This reinforces the dominant and distinct contributions of material surface chemistry to twitching speed and biofilm formation.
Collapse
Affiliation(s)
- Alessandro
M. Carabelli
- Advanced
Materials and Healthcare Technologies, School of Pharmacy, University of Nottingham, Nottingham NG7 2RD, U.K.
| | - Marco Isgró
- Advanced
Materials and Healthcare Technologies, School of Pharmacy, University of Nottingham, Nottingham NG7 2RD, U.K.
| | - Olutoba Sanni
- Advanced
Materials and Healthcare Technologies, School of Pharmacy, University of Nottingham, Nottingham NG7 2RD, U.K.
| | | | - David A. Winkler
- Advanced
Materials and Healthcare Technologies, School of Pharmacy, University of Nottingham, Nottingham NG7 2RD, U.K.
- Monash
Institute of Pharmaceutical Sciences, Monash
University, Parkville 3052, Australia
- La Trobe
Institute for Molecular Science, la Trobe
University, Bundoora 3083, Australia
- CSIRO
Data61, Pullenvale 4069, Australia
| | - Laurence Burroughs
- Advanced
Materials and Healthcare Technologies, School of Pharmacy, University of Nottingham, Nottingham NG7 2RD, U.K.
| | - Andrew J. Blok
- Division
of Molecular Therapeutics and Formulation, School of Pharmacy, University of Nottingham, Nottingham, NG7 2RD, U.K.
| | - Jean-Frédéric Dubern
- Biodiscovery
Institute and School of Life Sciences, University
of Nottingham, Nottingham NG7 2RD, U.K.
| | - Francesco Pappalardo
- Advanced
Materials and Healthcare Technologies, School of Pharmacy, University of Nottingham, Nottingham NG7 2RD, U.K.
| | - Andrew L. Hook
- Advanced
Materials and Healthcare Technologies, School of Pharmacy, University of Nottingham, Nottingham NG7 2RD, U.K.
| | - Paul Williams
- Biodiscovery
Institute and School of Life Sciences, University
of Nottingham, Nottingham NG7 2RD, U.K.
| | - Morgan R. Alexander
- Advanced
Materials and Healthcare Technologies, School of Pharmacy, University of Nottingham, Nottingham NG7 2RD, U.K.
| |
Collapse
|
30
|
Lee SW, Phillips KS, Gu H, Kazemzadeh-Narbat M, Ren D. How microbes read the map: Effects of implant topography on bacterial adhesion and biofilm formation. Biomaterials 2020; 268:120595. [PMID: 33360301 DOI: 10.1016/j.biomaterials.2020.120595] [Citation(s) in RCA: 70] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Revised: 11/24/2020] [Accepted: 12/06/2020] [Indexed: 12/19/2022]
Abstract
Microbes have remarkable capabilities to attach to the surface of implanted medical devices and form biofilms that adversely impact device function and increase the risk of multidrug-resistant infections. The physicochemical properties of biomaterials have long been known to play an important role in biofilm formation. More recently, a series of discoveries in the natural world have stimulated great interest in the use of 3D surface topography to engineer antifouling materials that resist bacterial colonization. There is also increasing evidence that some medical device surface topographies, such as those designed for tissue integration, may unintentionally promote microbial attachment. Despite a number of reviews on surface topography and biofilm control, there is a missing link between how bacteria sense and respond to 3D surface topographies and the rational design of antifouling materials. Motivated by this gap, we present a review of how bacteria interact with surface topographies, and what can be learned from current laboratory studies of microbial adhesion and biofilm formation on specific topographic features and medical devices. We also address specific biocompatibility considerations and discuss how to improve the assessment of the anti-biofilm performance of topographic surfaces. We conclude that 3D surface topography, whether intended or unintended, is an important consideration in the rational design of safe medical devices. Future research on next-generation smart antifouling materials could benefit from a greater focus on translation to real-world applications.
Collapse
Affiliation(s)
- Sang Won Lee
- Department of Biomedical and Chemical Engineering, Syracuse University, Syracuse, NY, 13244, United States; Syracuse Biomaterials Institute, Syracuse University, Syracuse, NY, 13244, United States
| | - K Scott Phillips
- United States Food and Drug Administration, Office of Medical Products and Tobacco, Center for Devices and Radiological Health, Office of Science and Engineering Laboratories, Division of Biology, Chemistry, and Materials Science, Silver Spring, MD, 20993, United States.
| | - Huan Gu
- Department of Biomedical and Chemical Engineering, Syracuse University, Syracuse, NY, 13244, United States; Syracuse Biomaterials Institute, Syracuse University, Syracuse, NY, 13244, United States
| | - Mehdi Kazemzadeh-Narbat
- United States Food and Drug Administration, Office of Medical Products and Tobacco, Center for Devices and Radiological Health, Office of Product Evaluation and Quality, Office of Health Technology 6, Silver Spring, MD, 20993, United States; Musculoskeletal Clinical Regulatory Advisers (MCRA), Washington DC, 20001, United States
| | - Dacheng Ren
- Department of Biomedical and Chemical Engineering, Syracuse University, Syracuse, NY, 13244, United States; Syracuse Biomaterials Institute, Syracuse University, Syracuse, NY, 13244, United States; Department of Civil and Environmental Engineering, Syracuse University, Syracuse, NY, 13244, United States; Department of Biology, Syracuse University, Syracuse, NY, 13244, United States.
| |
Collapse
|
31
|
Xu LC, Chen C, Zhu J, Tang M, Chen A, Allcock HR, Siedlecki CA. New cross-linkable poly[bis(octafluoropentoxy) phosphazene] biomaterials: Synthesis, surface characterization, bacterial adhesion, and plasma coagulation responses. J Biomed Mater Res B Appl Biomater 2020; 108:3250-3260. [PMID: 32558200 PMCID: PMC9427203 DOI: 10.1002/jbm.b.34662] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2020] [Revised: 04/13/2020] [Accepted: 05/19/2020] [Indexed: 12/20/2022]
Abstract
Biomaterial-associated microbial infection and thrombosis represent major issues to the success of long-term use of implantable blood-contacting medical devices. The development of new poly[bis(octafluoropentoxy) phosphazene (OFP) biomaterials provides new routes for combatting microbial infection and thrombosis. However, the limited mechanical properties of OFP to date render them unsuitable for application in medical devices and inhibit any attempts at subsequent surface topography modification. In this study, we synthesized cross-linkable OFPs (X-OFPs) with the different degrees of cross-linking in an effort to improve the mechanical properties. The results showed that the surface chemistry and surface topography of X-OFPs do not change significantly, but the surface mechanical stiffness increased after cross-linking. Atomic force microscopic phase images showed that the polymer phase separation structures changed due to cross-linking. Experiments with three bacterial strains: Staphylococcal epidermidis, Staphylococcal aureus, and Pseudomonas aeruginosa showed that bacterial adhesion was significantly decreased on the OFP and X-OFPs for both the pre-cross-linked and cross-linked as compared to polyurethane biomaterials. Furthermore, bacterial adhesions were lower on X-OFP surfaces than on pre-cross-linked materials, suggesting that mechanical stiffness is an important parameter influencing bacterial adhesion. Blood plasma coagulation responses revealed longer coagulation times for OFP and X-OFP materials than on polyurethanes, indicating that the new cross-linked OFPs are resistant to plasma coagulation compared to currently used polyurethane biomaterials.
Collapse
Affiliation(s)
- Li-Chong Xu
- Department of Surgery, The Pennsylvania State University, College of Medicine, Hershey, PA 17033, United States
| | - Chen Chen
- Department of Chemistry, The Pennsylvania State University, University Park, PA 16802, United States
| | - Jieru Zhu
- Department of Chemistry, The Pennsylvania State University, University Park, PA 16802, United States
| | - Meixian Tang
- Department of Biomedical Engineering, The Pennsylvania State University, College of Medicine, Hershey, PA 17033, United States
| | - Andy Chen
- Hershey High School, Hershey, PA 17033, United States
| | - Harry R. Allcock
- Department of Chemistry, The Pennsylvania State University, University Park, PA 16802, United States
| | - Christopher A. Siedlecki
- Department of Surgery, The Pennsylvania State University, College of Medicine, Hershey, PA 17033, United States
- Department of Biomedical Engineering, The Pennsylvania State University, College of Medicine, Hershey, PA 17033, United States
| |
Collapse
|
32
|
Al-Qatatsheh A, Morsi Y, Zavabeti A, Zolfagharian A, Salim N, Z. Kouzani A, Mosadegh B, Gharaie S. Blood Pressure Sensors: Materials, Fabrication Methods, Performance Evaluations and Future Perspectives. SENSORS (BASEL, SWITZERLAND) 2020; 20:E4484. [PMID: 32796604 PMCID: PMC7474433 DOI: 10.3390/s20164484] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 07/31/2020] [Accepted: 08/04/2020] [Indexed: 12/14/2022]
Abstract
Advancements in materials science and fabrication techniques have contributed to the significant growing attention to a wide variety of sensors for digital healthcare. While the progress in this area is tremendously impressive, few wearable sensors with the capability of real-time blood pressure monitoring are approved for clinical use. One of the key obstacles in the further development of wearable sensors for medical applications is the lack of comprehensive technical evaluation of sensor materials against the expected clinical performance. Here, we present an extensive review and critical analysis of various materials applied in the design and fabrication of wearable sensors. In our unique transdisciplinary approach, we studied the fundamentals of blood pressure and examined its measuring modalities while focusing on their clinical use and sensing principles to identify material functionalities. Then, we carefully reviewed various categories of functional materials utilized in sensor building blocks allowing for comparative analysis of the performance of a wide range of materials throughout the sensor operational-life cycle. Not only this provides essential data to enhance the materials' properties and optimize their performance, but also, it highlights new perspectives and provides suggestions to develop the next generation pressure sensors for clinical use.
Collapse
Affiliation(s)
- Ahmed Al-Qatatsheh
- Faculty of Science, Engineering, and Technology (FSET), Swinburne University of Technology, Melbourne VIC 3122, Australia; (Y.M.); (N.S.)
| | - Yosry Morsi
- Faculty of Science, Engineering, and Technology (FSET), Swinburne University of Technology, Melbourne VIC 3122, Australia; (Y.M.); (N.S.)
| | - Ali Zavabeti
- Department of Chemical Engineering, The University of Melbourne, Parkville VIC 3010, Australia;
| | - Ali Zolfagharian
- Faculty of Science, Engineering and Built Environment, School of Engineering, Deakin University, Waurn Ponds VIC 3216, Australia; (A.Z.); (A.Z.K.)
| | - Nisa Salim
- Faculty of Science, Engineering, and Technology (FSET), Swinburne University of Technology, Melbourne VIC 3122, Australia; (Y.M.); (N.S.)
| | - Abbas Z. Kouzani
- Faculty of Science, Engineering and Built Environment, School of Engineering, Deakin University, Waurn Ponds VIC 3216, Australia; (A.Z.); (A.Z.K.)
| | - Bobak Mosadegh
- Dalio Institute of Cardiovascular Imaging, Weill Cornell Medicine, New York, NY 10065, USA;
| | - Saleh Gharaie
- Faculty of Science, Engineering and Built Environment, School of Engineering, Deakin University, Waurn Ponds VIC 3216, Australia; (A.Z.); (A.Z.K.)
| |
Collapse
|
33
|
Gdaniec BG, Allard PM, Queiroz EF, Wolfender JL, van Delden C, Köhler T. Surface sensing triggers a broad-spectrum antimicrobial response in Pseudomonas aeruginosa. Environ Microbiol 2020; 22:3572-3587. [PMID: 32573899 PMCID: PMC7496599 DOI: 10.1111/1462-2920.15139] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Revised: 06/15/2020] [Accepted: 06/21/2020] [Indexed: 12/14/2022]
Abstract
Interspecies bacterial competition may occur via cell‐associated or secreted determinants and is key to successful niche colonization. We previously evolved Pseudomonas aeruginosa in the presence of Staphylococcus aureus and identified mutations in the Wsp surface‐sensing signalling system. Surprisingly, a ΔwspF mutant, characterized by increased c‐di‐GMP levels and biofilm formation capacity, showed potent killing activity towards S. aureus in its culture supernatant. Here, we used an unbiased metabolomic analysis of culture supernatants to identify rhamnolipids, alkyl quinoline N‐oxides and two siderophores as members of four chemical clusters, which were more abundant in the ΔwspF mutant supernatants. Killing activities were quorum‐sensing controlled but independent of c‐di‐GMP levels. Based on the metabolomic analysis, we formulated a synthetic cocktail of four compounds, showing broad‐spectrum anti‐bacterial killing, including both Gram‐positive and Gram‐negative bacteria. The combination of quorum‐sensing‐controlled killing and Wsp‐system mediated biofilm formation endows P. aeruginosa with capacities essential for niche establishment and host colonization.
Collapse
Affiliation(s)
- Bartosz Gerard Gdaniec
- Transplant Infectious Diseases Unit, University Hospital Geneva, Geneva, Switzerland.,Department of Microbiology and Molecular Medicine, University of Geneva, Geneva, Switzerland
| | - Pierre-Marie Allard
- School of Pharmaceutical Sciences, EPGL, University of Geneva, University of Lausanne, Geneva, Switzerland
| | - Emerson Ferreira Queiroz
- School of Pharmaceutical Sciences, EPGL, University of Geneva, University of Lausanne, Geneva, Switzerland
| | - Jean-Luc Wolfender
- School of Pharmaceutical Sciences, EPGL, University of Geneva, University of Lausanne, Geneva, Switzerland
| | - Christian van Delden
- Transplant Infectious Diseases Unit, University Hospital Geneva, Geneva, Switzerland.,Department of Microbiology and Molecular Medicine, University of Geneva, Geneva, Switzerland
| | - Thilo Köhler
- Transplant Infectious Diseases Unit, University Hospital Geneva, Geneva, Switzerland.,Department of Microbiology and Molecular Medicine, University of Geneva, Geneva, Switzerland
| |
Collapse
|
34
|
McGivney E, Cederholm L, Barth A, Hakkarainen M, Hamacher-Barth E, Ogonowski M, Gorokhova E. Rapid Physicochemical Changes in Microplastic Induced by Biofilm Formation. Front Bioeng Biotechnol 2020; 8:205. [PMID: 32266235 PMCID: PMC7103643 DOI: 10.3389/fbioe.2020.00205] [Citation(s) in RCA: 70] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Accepted: 03/02/2020] [Indexed: 11/23/2022] Open
Abstract
Risk assessment of microplastic (MP) pollution requires understanding biodegradation processes and related changes in polymer properties. In the environment, there are two-way interactions between the MP properties and biofilm communities: (i) microorganisms may prefer some surfaces, and (ii) MP surface properties change during the colonization and weathering. In a 2-week experiment, we studied these interactions using three model plastic beads (polyethylene [PE], polypropylene [PP], and polystyrene [PS]) exposed to ambient bacterioplankton assemblage from the Baltic Sea; the control beads were exposed to bacteria-free water. For each polymer, the physicochemical properties (compression, crystallinity, surface chemistry, hydrophobicity, and surface topography) were compared before and after exposure under controlled laboratory conditions. Furthermore, we characterized the bacterial communities on the MP surfaces using 16S rRNA gene sequencing and correlated community diversity to the physicochemical properties of the MP. Significant changes in PE crystallinity, PP stiffness, and PS maximum compression were observed as a result of exposure to bacteria. Moreover, there were significant correlations between bacterial diversity and some physicochemical characteristics (crystallinity, stiffness, and surface roughness). These changes coincided with variation in the relative abundance of unique OTUs, mostly related to the PE samples having significantly higher contribution of Sphingobium, Novosphingobium, and uncultured Planctomycetaceae compared to the other test materials, whereas PP and PS samples had significantly higher abundance of Sphingobacteriales and Alphaproteobacteria, indicating possible involvement of these taxa in the initial biodegradation steps. Our findings demonstrate measurable signs of MP weathering under short-term exposure to environmentally relevant microbial communities at conditions resembling those in the water column. A systematic approach for the characterization of the biodegrading capacity in different systems will improve the risk assessment of plastic litter in aquatic environments.
Collapse
Affiliation(s)
- Eric McGivney
- Department of Environmental Science, Stockholm University, Stockholm, Sweden
| | - Linnea Cederholm
- Department of Fibre and Polymer Technology, KTH Royal Institute of Technology, Stockholm, Sweden
| | - Andreas Barth
- Department of Biochemistry and Biophysics, Stockholm University, Stockholm, Sweden
| | - Minna Hakkarainen
- Department of Fibre and Polymer Technology, KTH Royal Institute of Technology, Stockholm, Sweden
| | | | - Martin Ogonowski
- Department of Environmental Science, Stockholm University, Stockholm, Sweden
| | - Elena Gorokhova
- Department of Environmental Science, Stockholm University, Stockholm, Sweden
| |
Collapse
|
35
|
Peng Q, Zhou X, Wang Z, Xie Q, Ma C, Zhang G, Gong X. Three-Dimensional Bacterial Motions near a Surface Investigated by Digital Holographic Microscopy: Effect of Surface Stiffness. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:12257-12263. [PMID: 31423792 DOI: 10.1021/acs.langmuir.9b02103] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Surface stiffness plays a critical role in bacterial adhesion, but the mechanism is unclear since the bacterial motion before adhesion is overlooked. Herein, the three-dimensional (3D) motions of Escherichia coli and Pseudonomas sp. nov 776 onto poly(dimethylsiloxane) (PDMS) surfaces with varying stiffness before adhering were monitored by digital holographic microscopy (DHM). As Young's modulus (E) of the PDMS surface decreases from 278.1 to 3.4 MPa, the adhered E. coli and Pseudonomas sp. decrease in number by 40.4 and 34.9%, respectively. Atomic force microscopy (AFM) measurements show that the adhesion force of bacteria to the surface declines with the decreased surface stiffness. In contrast, a nontumbling mutant of adhered E. coli (HCB1414 with the adaptive function being partially deficient) decreases much less (by 18.4%). On the other hand, the tumble frequency (Ft) of E. coli HCB1 and flick frequency (Ff) of Pseudomonas sp. increase as the surface stiffness decreases, and the motion bias (Bθ) of Pseudomonas sp. also increases. These facts clearly indicate that the bacteria have adapted responses to the surface stiffness. RNA sequencing (RNA-seq) reveals that the downregulated Cph2 and CsrA as well as the upregulated GcvA of swimming E. coli HCB1 in bulk near the softer surface promote the bacterial motility.
Collapse
Affiliation(s)
- Qingmei Peng
- Faculty of Materials Science and Engineering , South China University of Technology , Guangzhou 510640 , P. R. China
| | - Xin Zhou
- Faculty of Materials Science and Engineering , South China University of Technology , Guangzhou 510640 , P. R. China
| | - Zhi Wang
- Faculty of Materials Science and Engineering , South China University of Technology , Guangzhou 510640 , P. R. China
| | - Qingyi Xie
- Faculty of Materials Science and Engineering , South China University of Technology , Guangzhou 510640 , P. R. China
| | - Chunfeng Ma
- Faculty of Materials Science and Engineering , South China University of Technology , Guangzhou 510640 , P. R. China
| | - Guangzhao Zhang
- Faculty of Materials Science and Engineering , South China University of Technology , Guangzhou 510640 , P. R. China
| | - Xiangjun Gong
- Faculty of Materials Science and Engineering , South China University of Technology , Guangzhou 510640 , P. R. China
| |
Collapse
|
36
|
Valentin JD, Qin XH, Fessele C, Straub H, van der Mei HC, Buhmann MT, Maniura-Weber K, Ren Q. Substrate viscosity plays an important role in bacterial adhesion under fluid flow. J Colloid Interface Sci 2019; 552:247-257. [DOI: 10.1016/j.jcis.2019.05.043] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2019] [Revised: 05/08/2019] [Accepted: 05/13/2019] [Indexed: 01/08/2023]
|
37
|
Pushing beyond the Envelope: the Potential Roles of OprF in Pseudomonas aeruginosa Biofilm Formation and Pathogenicity. J Bacteriol 2019; 201:JB.00050-19. [PMID: 31010902 DOI: 10.1128/jb.00050-19] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The ability of Pseudomonas aeruginosa to form biofilms, which are communities of cells encased in a self-produced extracellular matrix, protects the cells from antibiotics and the host immune response. While some biofilm matrix components, such as exopolysaccharides and extracellular DNA, are relatively well characterized, the extracellular matrix proteins remain understudied. Multiple proteomic analyses of the P. aeruginosa soluble biofilm matrix and outer membrane vesicles, which are a component of the matrix, have identified OprF as an abundant matrix protein. To date, the few reports on the effects of oprF mutations on biofilm formation are conflicting, and little is known about the potential role of OprF in the biofilm matrix. The majority of OprF studies focus on the protein as a cell-associated porin. As a component of the outer membrane, OprF assumes dual conformations and is involved in solute transport, as well as cell envelope integrity. Here, we review the current literature on OprF in P. aeruginosa, discussing how the structure and function of the cell-associated and matrix-associated protein may affect biofilm formation and pathogenesis in order to inform future research on this understudied matrix protein.
Collapse
|
38
|
Gordon VD, Wang L. Bacterial mechanosensing: the force will be with you, always. J Cell Sci 2019; 132:132/7/jcs227694. [PMID: 30944157 DOI: 10.1242/jcs.227694] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Whether bacteria are in the planktonic state, free-swimming or free-floating in liquid, or in the biofilm state, sessile on surfaces, they are always subject to mechanical forces. The long, successful evolutionary history of bacteria implies that they are capable of adapting to varied mechanical forces, and probably even actively respond to mechanical cues in their changing environments. However, the sensing of mechanical cues by bacteria, or bacterial mechanosensing, has been under-investigated. This leaves the mechanisms underlying how bacteria perceive and respond to mechanical cues largely unknown. In this Review, we first examine the surface-associated behavior of bacteria, outline the clear evidence for bacterial mechanosensing and summarize the role of flagella, type-IV pili, and envelope proteins as potential mechanosensors, before presenting indirect evidence for mechanosensing in bacteria. The general themes underlying bacterial mechanosensing that we highlight here may provide a framework for future research.
Collapse
Affiliation(s)
- Vernita D Gordon
- Department of Physics and Center for Nonlinear Dynamics, The University of Texas at Austin, Austin, TX 78712, USA .,Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, TX 78712, USA
| | - Liyun Wang
- Department of Physics and Center for Nonlinear Dynamics, The University of Texas at Austin, Austin, TX 78712, USA
| |
Collapse
|
39
|
Cheng Y, Feng G, Moraru CI. Micro- and Nanotopography Sensitive Bacterial Attachment Mechanisms: A Review. Front Microbiol 2019; 10:191. [PMID: 30846973 PMCID: PMC6393346 DOI: 10.3389/fmicb.2019.00191] [Citation(s) in RCA: 149] [Impact Index Per Article: 29.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Accepted: 01/23/2019] [Indexed: 12/16/2022] Open
Abstract
Bacterial attachment to material surfaces can lead to the development of biofilms that cause severe economic and health problems. The outcome of bacterial attachment is determined by a combination of bacterial sensing of material surfaces by the cell and the physicochemical factors in the near-surface environment. This paper offers a systematic review of the effects of surface topography on a range of antifouling mechanisms, with a focus on how topographical scale, from micro- to nanoscale, may influence bacterial sensing of and attachment to material surfaces. A good understanding of these mechanisms can facilitate the development of antifouling surfaces based on surface topography, with applications in various sectors of human life and activity including healthcare, food, and water treatment.
Collapse
Affiliation(s)
- Yifan Cheng
- Department of Food Science, Cornell University, Ithaca, NY, United States
| | | | - Carmen I. Moraru
- Department of Food Science, Cornell University, Ithaca, NY, United States
| |
Collapse
|
40
|
Kolewe KW, Kalasin S, Shave M, Schiffman JD, Santore MM. Mechanical Properties and Concentrations of Poly(ethylene glycol) in Hydrogels and Brushes Direct the Surface Transport of Staphylococcus aureus. ACS APPLIED MATERIALS & INTERFACES 2019; 11:320-330. [PMID: 30595023 PMCID: PMC6771038 DOI: 10.1021/acsami.8b18302] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Surface-associated transport of flowing bacteria, including cell rolling, is a mechanism for otherwise immobile bacteria to migrate on surfaces and could be associated with biofilm formation or the spread of infection. This work demonstrates how the moduli and/or local polymer concentration play critical roles in sustaining contact, dynamic adhesion, and transport of bacterial cells along a hydrogel or hydrated brush surface. In particular, stiffer more concentrated hydrogels and brushes maintained the greatest dynamic contact, still allowing cells to travel along the surface in flow. This study addressed how the mechanical properties, molecular architectures, and thicknesses of minimally adhesive poly(ethylene glycol) (PEG)-based coatings influence the flow-driven surface motion of Staphylococcus aureus MS2 cells. Three protein-repellant PEG-dimethylacrylate hydrogel films (∼100 μm thick) and two protein-repellant PEG brushes (8-16 nm thick) were sufficiently fouling-resistant to prevent the accumulation of flowing bacteria. However, the rolling or hopping-like motions of gently flowing S. aureus cells along the surfaces were specific to the particular hydrogel or brush, distinguishing these coatings in terms of their mechanical properties (with moduli from 2 to 1300 kPa) or local PEG concentrations (in the range 10-50% PEG). On the stiffer hydrogel coatings having higher PEG concentrations, S. aureus exhibited long runs of surface rolling, 20-50 μm in length, an increased tendency of cells to repeatedly return to some surfaces after rolling and escaping, and relatively long integrated contact times. By contrast, on the softer more dilute hydrogels, bacteria tended to encounter the surface for brief periods before escaping without return. The dynamic adhesion and motion signatures of the cells on the two brushes were bracketed by those on the soft and stiff hydrogels, demonstrating that PEG coating thickness was not important in these studies where the vertically oriented surfaces minimized the impact of gravitational forces. Control studies with similarly sized poly(ethylene oxide)-coated rigid spherical microparticles, that also did not arrest on the PEG coatings, established that the bacterial skipping and rolling signatures were specific to the S. aureus cells and not simply diffusive. Dynamic adhesion of the S. aureus cells on the PEG hydrogel surfaces correlated well with quiescent 24 h adhesion studies in the literature, despite the orientation of the flow studies that eliminated the influence of gravity on bacteria-coating normal forces.
Collapse
Affiliation(s)
- Kristopher W. Kolewe
- Department of Chemical Engineering, University of Massachusetts Amherst, Amherst, Massachusetts 01003-9303, United States
| | - Surachate Kalasin
- Department of Polymer Science and Engineering, University of Massachusetts Amherst, Amherst, Massachusetts 01003-9303, United States
| | - Molly Shave
- Department of Polymer Science and Engineering, University of Massachusetts Amherst, Amherst, Massachusetts 01003-9303, United States
| | - Jessica D. Schiffman
- Department of Chemical Engineering, University of Massachusetts Amherst, Amherst, Massachusetts 01003-9303, United States
| | - Maria M. Santore
- Department of Polymer Science and Engineering, University of Massachusetts Amherst, Amherst, Massachusetts 01003-9303, United States
| |
Collapse
|
41
|
Lee SW, Gu H, Kilberg JB, Ren D. Sensitizing bacterial cells to antibiotics by shape recovery triggered biofilm dispersion. Acta Biomater 2018; 81:93-102. [PMID: 30267885 DOI: 10.1016/j.actbio.2018.09.042] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Revised: 09/04/2018] [Accepted: 09/25/2018] [Indexed: 12/15/2022]
Abstract
Microbial biofilms are a leading cause of chronic infections in humans and persistent biofouling in industries due to extremely high-level tolerance of biofilm cells to antimicrobial agents. Eradicating mature biofilms is especially challenging because of the protection of the extracellular matrix and slow growth of biofilm cells. Recently, we reported that established biofilms can be effectively removed (e.g. 99.9% dispersion of 48 h Pseudomonas aeruginosa PAO1 biofilms) by shape memory polymer-based dynamic changes in surface topography. Here, we demonstrate that such biofilm dispersion also sensitizes biofilm cells to conventional antibiotics. For example, shape recovery in the presence of 50 µg/mL tobramycin reduced biofilm cell counts by more than 3 logs (2,479-fold) compared to the static flat control. The observed effects were attributed to the disruption of biofilm structure and increase in cellular activities as evidenced by an 11.8-fold increase in intracellular level of adenosine triphosphate (ATP), and 4.1-fold increase in expression of the rrnB gene in detached cells. These results can help guide the design of new control methods to better combat biofilm associated antibiotic-resistant infections. STATEMENT OF SIGNIFICANCE: Microbial infections are challenging due to high-level antibiotic resistance of biofilm cells. The protection of an extracellular matrix and slow growth of biofilm cells render conventional antibiotics ineffective. Thus, it is important to develop new technologies that can remove mature biofilms and sensitize biofilm cells to antibiotics. Recently, we demonstrated that dynamic change in surface topography can remove 48 h Pseudomonas aeruginosa PAO1 biofilms by 99.9%. In this study, we investigated how shape recovery triggered dispersion affect the physiology of biofilm cells and associated antibiotic susceptibility. These results are helpful for understanding biofilm dispersion and developing more effective control methods.
Collapse
Affiliation(s)
- Sang Won Lee
- Department of Biomedical and Chemical Engineering, Syracuse University, Syracuse, NY 13244, United States; Syracuse Biomaterials Institute, Syracuse University, Syracuse, NY 13244, United States
| | - Huan Gu
- Department of Biomedical and Chemical Engineering, Syracuse University, Syracuse, NY 13244, United States; Syracuse Biomaterials Institute, Syracuse University, Syracuse, NY 13244, United States
| | - James Bryan Kilberg
- Department of Biomedical and Chemical Engineering, Syracuse University, Syracuse, NY 13244, United States
| | - Dacheng Ren
- Department of Biomedical and Chemical Engineering, Syracuse University, Syracuse, NY 13244, United States; Syracuse Biomaterials Institute, Syracuse University, Syracuse, NY 13244, United States; Department of Civil and Environmental Engineering, Syracuse University, Syracuse, NY 13244, United States; Department of Biology, Syracuse University, Syracuse, NY 13244, United States.
| |
Collapse
|