1
|
O'Hara MT, Shimozono TM, Dye KJ, Harris D, Yang Z. Surface hydrophilicity promotes bacterial twitching motility. mSphere 2024:e0039024. [PMID: 39194233 DOI: 10.1128/msphere.00390-24] [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: 05/14/2024] [Accepted: 06/24/2024] [Indexed: 08/29/2024] Open
Abstract
Twitching motility is a form of bacterial surface translocation powered by the type IV pilus (T4P). It is frequently analyzed by interstitial colony expansion between agar and the polystyrene surfaces of petri dishes. In such assays, the twitching motility of Acinetobacter nosocomialis was observed with MacConkey but not Luria-Bertani (LB) agar media. One difference between these two media is the presence of bile salts as a selective agent in MacConkey but not in LB. Here, we demonstrate that the addition of bile salts to LB allowed A. nosocomialis to display twitching. Similarly, bile salts enhanced the twitching of Acinetobacter baumannii and Pseudomonas aeruginosa in LB. These observations suggest that there is a common mechanism, whereby bile salts enhance bacterial twitching and promote interstitial colony expansion. Bile salts disrupt lipid membranes and apply envelope stress as detergents. Surprisingly, their stimulatory effect on twitching appears not to be related to a bacterial physiological response to stressors. Rather, it is due to their ability to alter the physicochemical properties of a twitching surface. We observed that while other detergents promoted twitching like bile salts, stresses applied by antibiotics, including the outer membrane-targeting polymyxin B, did not enhance twitching motility. More importantly, bacteria displayed increased twitching on hydrophilic surfaces such as those of glass and tissue culture-treated polystyrene plastics, and bile salts no longer stimulated twitching on these surfaces. Together, our results show that altering the hydrophilicity of a twitching surface significantly impacts T4P functionality. IMPORTANCE The bacterial type IV pilus (T4P) is a critical virulence factor for many medically important pathogens, some of which are prioritized by the World Health Organization for their high levels of antibiotic resistance. The T4P is known to propel bacterial twitching motility, the analysis of which provides a convenient assay for T4P functionality. Here, we show that bile salts and other detergents augment the twitching of multiple bacterial pathogens. We identified the underlying mechanism as the alteration of surface hydrophilicity by detergents. Consequently, hydrophilic surfaces like those of glass or plasma-treated polystyrene promote bacterial twitching, bypassing the requirement for detergents. The implication is that surface properties, such as those of tissues and medical implants, significantly impact the functionality of bacterial T4P as a virulence determinant. This offers valuable insights for developing countermeasures against the colonization and infection by bacterial pathogens of critical importance to human health on a global scale.
Collapse
Affiliation(s)
- Megan T O'Hara
- Department of Biological Sciences, Virginia Tech, Blacksburg, Virginia, USA
| | - Tori M Shimozono
- Department of Biological Sciences, Virginia Tech, Blacksburg, Virginia, USA
| | - Keane J Dye
- Department of Biological Sciences, Virginia Tech, Blacksburg, Virginia, USA
| | - David Harris
- Department of Biological Sciences, Virginia Tech, Blacksburg, Virginia, USA
| | - Zhaomin Yang
- Department of Biological Sciences, Virginia Tech, Blacksburg, Virginia, USA
| |
Collapse
|
2
|
Xu Q, Ali S, Afzal M, Nizami AS, Han S, Dar MA, Zhu D. Advancements in bacterial chemotaxis: Utilizing the navigational intelligence of bacteria and its practical applications. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 931:172967. [PMID: 38705297 DOI: 10.1016/j.scitotenv.2024.172967] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2024] [Revised: 04/06/2024] [Accepted: 05/01/2024] [Indexed: 05/07/2024]
Abstract
The fascinating world of microscopic life unveils a captivating spectacle as bacteria effortlessly maneuver through their surroundings with astonishing accuracy, guided by the intricate mechanism of chemotaxis. This review explores the complex mechanisms behind this behavior, analyzing the flagellum as the driving force and unraveling the intricate signaling pathways that govern its movement. We delve into the hidden costs and benefits of this intricate skill, analyzing its potential to propagate antibiotic resistance gene while shedding light on its vital role in plant colonization and beneficial symbiosis. We explore the realm of human intervention, considering strategies to manipulate bacterial chemotaxis for various applications, including nutrient cycling, algal bloom and biofilm formation. This review explores the wide range of applications for bacterial capabilities, from targeted drug delivery in medicine to bioremediation and disease control in the environment. Ultimately, through unraveling the intricacies of bacterial movement, we can enhance our comprehension of the intricate web of life on our planet. This knowledge opens up avenues for progress in fields such as medicine, agriculture, and environmental conservation.
Collapse
Affiliation(s)
- Qi Xu
- International Joint Laboratory on Synthetic Biology and Biomass Biorefinery, Biofuels Institute, School of Emergency Management, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang 212013, PR China
| | - Shehbaz Ali
- International Joint Laboratory on Synthetic Biology and Biomass Biorefinery, Biofuels Institute, School of Emergency Management, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang 212013, PR China; Jiangsu Collaborative Innovation Center of Technology and Material of Water Treatment, Suzhou University of Science and Technology, Suzhou 215009, PR China
| | - Muhammad Afzal
- Soil & Environmental Biotechnology Division, National Institute for Biotechnology and Genetic Engineering, Faisalabad, Pakistan
| | - Abdul-Sattar Nizami
- Sustainable Development Study Centre, Government College University, Lahore 54000, Pakistan
| | - Song Han
- Jiangsu Collaborative Innovation Center of Technology and Material of Water Treatment, Suzhou University of Science and Technology, Suzhou 215009, PR China
| | - Mudasir A Dar
- International Joint Laboratory on Synthetic Biology and Biomass Biorefinery, Biofuels Institute, School of Emergency Management, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang 212013, PR China
| | - Daochen Zhu
- International Joint Laboratory on Synthetic Biology and Biomass Biorefinery, Biofuels Institute, School of Emergency Management, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang 212013, PR China; Jiangsu Collaborative Innovation Center of Technology and Material of Water Treatment, Suzhou University of Science and Technology, Suzhou 215009, PR China.
| |
Collapse
|
3
|
Warrell DL, Zarrella TM, Machalek C, Khare A. Interspecies surfactants serve as public goods enabling surface motility in Pseudomonas aeruginosa. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.03.573969. [PMID: 38260674 PMCID: PMC10802355 DOI: 10.1101/2024.01.03.573969] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
In most natural environments, bacteria live in polymicrobial communities where secreted molecules from neighboring species alter bacterial behaviors including motility, but such interactions are understudied. Pseudomonas aeruginosa is a motile opportunistic pathogen that exists in diverse multispecies environments such as the soil and is frequently found in human wound and respiratory tract co-infections with other bacteria including Staphylococcus aureus. Here we show that P. aeruginosa can co-opt secreted surfactants from other species for flagellar-based surface motility. We found that exogenous surfactants from S. aureus, other bacteria, and interkingdom species enabled P. aeruginosa to switch from swarming to an alternative surface spreading motility on semi-solid surfaces and allowed for the emergence of surface motility on hard agar where P. aeruginosa was otherwise unable to move. This motility was distinct from the response of other motile bacteria in the presence of exogenous surfactants. Mutant analysis indicated that this P. aeruginosa motility was similar to a previously described mucin-based motility, 'surfing', albeit with divergent regulation. Thus, our study demonstrates that secreted surfactants from the host as well as neighboring bacterial and interkingdom species act as public goods facilitating P. aeruginosa flagella-mediated surfing-like surface motility, thereby allowing it to access different environmental niches.
Collapse
Affiliation(s)
- Delayna L Warrell
- Laboratory of Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - Tiffany M Zarrella
- Laboratory of Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
- Postdoctoral Research Associate Training Program, National Institute of General Medical Sciences, National Institutes of Health, Bethesda, MD, USA
- Current address: Department of Biology, Georgetown University, Washington, DC, USA
| | - Christopher Machalek
- Laboratory of Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - Anupama Khare
- Laboratory of Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| |
Collapse
|
4
|
Carvia-Hermoso C, Cuéllar V, Bernabéu-Roda LM, van Dillewijn P, Soto MJ. Sinorhizobium meliloti GR4 Produces Chromosomal- and pSymA-Encoded Type IVc Pili That Influence the Interaction with Alfalfa Plants. PLANTS (BASEL, SWITZERLAND) 2024; 13:628. [PMID: 38475474 DOI: 10.3390/plants13050628] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2024] [Revised: 02/09/2024] [Accepted: 02/23/2024] [Indexed: 03/14/2024]
Abstract
Type IVc Pili (T4cP), also known as Tad or Flp pili, are long thin microbial filaments that are made up of small-sized pilins. These appendages serve different functions in bacteria, including attachment, biofilm formation, surface sensing, motility, and host colonization. Despite their relevant role in diverse microbial lifestyles, knowledge about T4cP in bacteria that establish symbiosis with legumes, collectively referred to as rhizobia, is still limited. Sinorhizobium meliloti contains two clusters of T4cP-related genes: flp-1 and flp-2, which are located on the chromosome and the pSymA megaplasmid, respectively. Bundle-forming pili associated with flp-1 are involved in the competitive nodulation of alfalfa plants, but the role of flp-2 remains elusive. In this work, we have performed a comprehensive bioinformatic analysis of T4cP genes in the highly competitive S. meliloti GR4 strain and investigated the role of its flp clusters in pilus biogenesis, motility, and in the interaction with alfalfa. Single and double flp-cluster mutants were constructed on the wild-type genetic background as well as in a flagellaless derivative strain. Our data demonstrate that both chromosomal and pSymA flp clusters are functional in pili biogenesis and contribute to surface translocation and nodule formation efficiency in GR4. In this strain, the presence of flp-1 in the absence of flp-2 reduces the competitiveness for nodule occupation.
Collapse
Affiliation(s)
- Cristina Carvia-Hermoso
- Department of Biotechnology and Environmental Protection, Estación Experimental del Zaidín, CSIC, 18008 Granada, Spain
| | - Virginia Cuéllar
- Department of Biotechnology and Environmental Protection, Estación Experimental del Zaidín, CSIC, 18008 Granada, Spain
| | - Lydia M Bernabéu-Roda
- Department of Biotechnology and Environmental Protection, Estación Experimental del Zaidín, CSIC, 18008 Granada, Spain
| | - Pieter van Dillewijn
- Department of Biotechnology and Environmental Protection, Estación Experimental del Zaidín, CSIC, 18008 Granada, Spain
| | - María J Soto
- Department of Biotechnology and Environmental Protection, Estación Experimental del Zaidín, CSIC, 18008 Granada, Spain
| |
Collapse
|
5
|
Weaver AA, Parmar D, Junker EA, Sweedler JV, Shrout JD. Differential Spreading of Rhamnolipid Congeners from Pseudomonas aeruginosa. ACS APPLIED BIO MATERIALS 2023; 6:4914-4921. [PMID: 37878954 PMCID: PMC11107424 DOI: 10.1021/acsabm.3c00641] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2023]
Abstract
Rhamnolipids are surfactants produced by many Pseudomonad bacteria, including the species Pseudomonas aeruginosa. These rhamnolipids are known to aid and enable numerous phenotypic traits that improve the survival of the bacteria that make them. These surfactants are also important for industrial products ranging from pharmaceuticals to cleaning supplies to cosmetics, to name a few. Rhamnolipids have structural diversity that leads to an array of congeners; however, little is known about the localization and distribution of these congeners in two-dimensional space. Differential distribution of congeners can reduce the uniformity of applications in industrial settings and create heterogeneity within biological communities. We examined the distribution patterns of combinations of rhamnolipids in commercially available mixtures, cell-free spent media, and colony biofilms using mass spectrometry. We found that even in the absence of cells, congeners exhibit different distribution patterns, leading to different rhamnolipid congener distributions on a surface. Congeners with shorter fatty acid chains were more centrally located, while longer chains were more heterogeneous and distally located. We found that congeners with similar structures can distribute differently. Within developing colony biofilms, we found rhamnolipid distribution patterns differed from cell-free environments, lacking simple trends noted in cell-free environments. Most strikingly, we found the distribution patterns of individual congeners in the colony biofilms to be diverse. We note that the congener distribution is far from homogeneous but composed of numerous local microenvironments of varied rhamnolipid congener composition.
Collapse
Affiliation(s)
- Abigail A. Weaver
- Department of Civil and Environmental Engineering and Earth Sciences, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Dharmeshkumar Parmar
- Department of Chemistry and Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Ella A. Junker
- Department of Civil and Environmental Engineering and Earth Sciences, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Jonathan V. Sweedler
- Department of Chemistry and Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Joshua D. Shrout
- Department of Civil and Environmental Engineering and Earth Sciences, University of Notre Dame, Notre Dame, Indiana 46556, United States
- Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana 46556, United States
| |
Collapse
|
6
|
Blanco-Romero E, Durán D, Garrido-Sanz D, Redondo-Nieto M, Martín M, Rivilla R. Adaption of Pseudomonas ogarae F113 to the Rhizosphere Environment-The AmrZ-FleQ Hub. Microorganisms 2023; 11:microorganisms11041037. [PMID: 37110460 PMCID: PMC10146422 DOI: 10.3390/microorganisms11041037] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Revised: 04/10/2023] [Accepted: 04/13/2023] [Indexed: 04/29/2023] Open
Abstract
Motility and biofilm formation are two crucial traits in the process of rhizosphere colonization by pseudomonads. The regulation of both traits requires a complex signaling network that is coordinated by the AmrZ-FleQ hub. In this review, we describe the role of this hub in the adaption to the rhizosphere. The study of the direct regulon of AmrZ and the phenotypic analyses of an amrZ mutant in Pseudomonas ogarae F113 has shown that this protein plays a crucial role in the regulation of several cellular functions, including motility, biofilm formation, iron homeostasis, and bis-(3'-5')-cyclic dimeric guanosine monophosphate (c-di-GMP) turnover, controlling the synthesis of extracellular matrix components. On the other hand, FleQ is the master regulator of flagellar synthesis in P. ogarae F113 and other pseudomonads, but its implication in the regulation of multiple traits related with environmental adaption has been shown. Genomic scale studies (ChIP-Seq and RNA-Seq) have shown that in P. ogarae F113, AmrZ and FleQ are general transcription factors that regulate multiple traits. It has also been shown that there is a common regulon shared by the two transcription factors. Moreover, these studies have shown that AmrZ and FleQ form a regulatory hub that inversely regulate traits such as motility, extracellular matrix component production, and iron homeostasis. The messenger molecule c-di-GMP plays an essential role in this hub since its production is regulated by AmrZ and it is sensed by FleQ and required for its regulatory role. This regulatory hub is functional both in culture and in the rhizosphere, indicating that the AmrZ-FleQ hub is a main player of P. ogarae F113 adaption to the rhizosphere environment.
Collapse
Affiliation(s)
- Esther Blanco-Romero
- Departamento de Biología, Facultad de Ciencias, Universidad Autónoma de Madrid, Darwin 2, 28049 Madrid, Spain
| | - David Durán
- Departamento de Biología, Facultad de Ciencias, Universidad Autónoma de Madrid, Darwin 2, 28049 Madrid, Spain
| | - Daniel Garrido-Sanz
- Departamento de Biología, Facultad de Ciencias, Universidad Autónoma de Madrid, Darwin 2, 28049 Madrid, Spain
- Department of Fundamental Microbiology, University of Lausanne, 1015 Lausanne, Switzerland
| | - Miguel Redondo-Nieto
- Departamento de Biología, Facultad de Ciencias, Universidad Autónoma de Madrid, Darwin 2, 28049 Madrid, Spain
| | - Marta Martín
- Departamento de Biología, Facultad de Ciencias, Universidad Autónoma de Madrid, Darwin 2, 28049 Madrid, Spain
| | - Rafael Rivilla
- Departamento de Biología, Facultad de Ciencias, Universidad Autónoma de Madrid, Darwin 2, 28049 Madrid, Spain
| |
Collapse
|
7
|
Deforet M. Long-range alteration of the physical environment mediates cooperation between Pseudomonas aeruginosa swarming colonies. Environ Microbiol 2023. [PMID: 36964975 DOI: 10.1111/1462-2920.16373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Accepted: 03/15/2023] [Indexed: 03/27/2023]
Abstract
Pseudomonas aeruginosa makes and secretes massive amounts of rhamnolipid surfactants that enable swarming motility over biogel surfaces. But how these rhamnolipids interact with biogels to assist swarming remains unclear. Here, I use a combination of optical techniques across scales and genetically engineered strains to demonstrate that rhamnolipids can induce agar gel swelling over distances >10,000× the body size of an individual cell. The swelling front is on the micrometric scale and is easily visible using shadowgraphy. Rhamnolipid transport is not restricted to the surface of the gel but occurs through the whole thickness of the plate and, consequently, the spreading dynamics depend on the local thickness. Surprisingly, rhamnolipids can cross the whole gel and induce swelling on the opposite side of a two-face Petri dish. The swelling front delimits an area where the mechanical properties of the surface properties are modified: water wets the surface more easily, which increases the motility of individual bacteria and enables collective motility. A genetically engineered mutant unable to secrete rhamnolipids (ΔrhlA), and therefore unable to swarm, is rescued from afar with rhamnolipids produced by a remote colony. These results exemplify the remarkable capacity of bacteria to change the physical environment around them and its ecological consequences.
Collapse
Affiliation(s)
- Maxime Deforet
- Sorbonne Université, Centre National de la Recherche Scientifique, Laboratoire Jean Perrin, LJP, Paris, 75005, France
| |
Collapse
|
8
|
Brito-Santana P, Duque-Pedraza JJ, Bernabéu-Roda LM, Carvia-Hermoso C, Cuéllar V, Fuentes-Romero F, Acosta-Jurado S, Vinardell JM, Soto MJ. Sinorhizobium meliloti DnaJ Is Required for Surface Motility, Stress Tolerance, and for Efficient Nodulation and Symbiotic Nitrogen Fixation. Int J Mol Sci 2023; 24:ijms24065848. [PMID: 36982921 PMCID: PMC10055731 DOI: 10.3390/ijms24065848] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Revised: 03/14/2023] [Accepted: 03/17/2023] [Indexed: 03/30/2023] Open
Abstract
Bacterial surface motility is a complex microbial trait that contributes to host colonization. However, the knowledge about regulatory mechanisms that control surface translocation in rhizobia and their role in the establishment of symbiosis with legumes is still limited. Recently, 2-tridecanone (2-TDC) was identified as an infochemical in bacteria that hampers microbial colonization of plants. In the alfalfa symbiont Sinorhizobium meliloti, 2-TDC promotes a mode of surface motility that is mostly independent of flagella. To understand the mechanism of action of 2-TDC in S. meliloti and unveil genes putatively involved in plant colonization, Tn5 transposants derived from a flagellaless strain that were impaired in 2-TDC-induced surface spreading were isolated and genetically characterized. In one of the mutants, the gene coding for the chaperone DnaJ was inactivated. Characterization of this transposant and newly obtained flagella-minus and flagella-plus dnaJ deletion mutants revealed that DnaJ is essential for surface translocation, while it plays a minor role in swimming motility. DnaJ loss-of-function reduces salt and oxidative stress tolerance in S. meliloti and hinders the establishment of efficient symbiosis by affecting nodule formation efficiency, cellular infection, and nitrogen fixation. Intriguingly, the lack of DnaJ causes more severe defects in a flagellaless background. This work highlights the role of DnaJ in the free-living and symbiotic lifestyles of S. meliloti.
Collapse
Affiliation(s)
- Paula Brito-Santana
- Estación Experimental del Zaidín, CSIC, Department of Biotechnology and Environmental Protection, 18008 Granada, Spain
| | - Julián J Duque-Pedraza
- Estación Experimental del Zaidín, CSIC, Department of Biotechnology and Environmental Protection, 18008 Granada, Spain
| | - Lydia M Bernabéu-Roda
- Estación Experimental del Zaidín, CSIC, Department of Biotechnology and Environmental Protection, 18008 Granada, Spain
| | - Cristina Carvia-Hermoso
- Estación Experimental del Zaidín, CSIC, Department of Biotechnology and Environmental Protection, 18008 Granada, Spain
| | - Virginia Cuéllar
- Estación Experimental del Zaidín, CSIC, Department of Biotechnology and Environmental Protection, 18008 Granada, Spain
| | - Francisco Fuentes-Romero
- Facultad de Biología, Departamento de Microbiología, Universidad de Sevilla, 41012 Sevilla, Spain
| | - Sebastián Acosta-Jurado
- Centro Andaluz de Biología del Desarrollo, CSIC, Junta de Andalucía, Departamento de Biología Molecular e Ingeniería Bioquímica, Universidad Pablo de Olavide, 41013 Seville, Spain
| | - José-María Vinardell
- Facultad de Biología, Departamento de Microbiología, Universidad de Sevilla, 41012 Sevilla, Spain
| | - María J Soto
- Estación Experimental del Zaidín, CSIC, Department of Biotechnology and Environmental Protection, 18008 Granada, Spain
| |
Collapse
|
9
|
Partridge JD, Harshey RM. Swarming Motility Assays in Salmonella. Methods Mol Biol 2023; 2646:147-158. [PMID: 36842113 PMCID: PMC10942719 DOI: 10.1007/978-1-0716-3060-0_13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/27/2023]
Abstract
Salmonella enterica has six subspecies, of which the subspecies enterica is the most important for human health. The dispersal and infectivity of this species are dependent upon flagella-driven motility. Two kinds of flagella-mediated movements have been described-swimming individually in bulk liquid and swarming collectively over a surface substrate. During swarming, the bacteria acquire a distinct physiology, the most significant consequence of which is acquisition of adaptive resistance to antibiotics. Described here are protocols to cultivate, verify, and study swimming and swarming motility in S. enterica, and an additional "border-crossing" assay, where cells "primed" to swarm are presented with an environmental challenge such as antibiotics to assess their propensity to handle the challenge.
Collapse
Affiliation(s)
- Jonathan D Partridge
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX, USA.
| | - Rasika M Harshey
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX, USA.
| |
Collapse
|
10
|
Surface characterisation reveals substrate suitability for cyanobacterial phototaxis. Acta Biomater 2023; 155:386-399. [PMID: 36280031 DOI: 10.1016/j.actbio.2022.10.035] [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: 05/18/2022] [Revised: 09/24/2022] [Accepted: 10/17/2022] [Indexed: 02/02/2023]
Abstract
Cyanobacteria respond to light stimulation, activating localised assembly of type IV pili for motility. The resulting phototactic response is highly dependent on the nature of the incoming light stimulus, and the final motility parameters depend on the surface properties. Conventionally, phototaxis studies are carried out on hydrogel surfaces, such as agarose, with surface properties that vary in time due to experimental conditions. This study considers five substrates, widely utilized in microfluidic technology, to identify the most suitable alternative for performing reliable and repeatable phototaxis assays. The surfaces are characterised via a contact angle goniometer to determine the surface energy, white light interferometry for roughness, zeta-potentials and AFM force distance curves for charge patterns, and XPS for surface composition. Cell motility assays showed 1.25 times increment on surfaces with a water contact angle of 80° compared to a reference glass surface. To prove that motility can be enhanced, polydimethylsiloxane (PDMS) surfaces were plasma treated to alter their surface wettability. The motility on the plasma-treated PDMS showed similar performance as for glass surfaces. In contrast, untreated PDMS surfaces displayed close to zero motility. We also describe the force interactions of cells with the test surfaces using DLVO (Derjaguin-Landau-Verwey-Overbeek) and XDLVO (extended DLVO) theories. The computed DLVO/XDLVO force-distance curves are compared with those obtained using atomic force microscopy. Our findings show that twitching motility on tested surfaces can be described mainly from adhesive forces and hydrophobicity/hydrophilicity surface properties. STATEMENT OF SIGNIFICANCE: The current article focuses on unravelling the potential Micro-Electro-Mechanical System (MEMS) compatible surfaces for studying phototactic twitching motility of cyanobacteria. This is the first exhaustive surface characterization study coupled with phototaxis experiments, to understand the forces contributing to twitching motility. The methods shown in this paper can be further extended to study other surfaces and also to other bacteria exhibiting twitching motility.
Collapse
|
11
|
Wu L, Fan J, Chen J, Fang F. Chemotaxis of Clostridium Strains Isolated from Pit Mud and Its Application in Baijiu Fermentation. Foods 2022; 11:foods11223639. [PMID: 36429231 PMCID: PMC9689628 DOI: 10.3390/foods11223639] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 11/08/2022] [Accepted: 11/11/2022] [Indexed: 11/16/2022] Open
Abstract
Clostridium is the key bacteria that inhabits the pit mud in a fermentation cell, for the production of strong-flavor Baijiu. Its activities in the process of Baijiu fermentation is closely related to the niches of pit mud and cells. After multiple rounds of underground fermentation, Clostridium has been domesticated and adapted to the environment. The mechanisms of clostridia succession in the pit mud and how they metabolize nutrients present in grains are not clear. In this study, 15 Clostridium species including three firstly reported ones (Clostridium tertium, Clostridium pabulibutyricum and Clostridium intestinale) in strong-flavor Baijiu pit mud, were isolated from the pit mud. Eighty one percent of these Clostridium strains are motile, and most of them show chemotaxis to organic acids, glutathione, saccharides and lactic acid bacteria. In a simulated Baijiu fermentation system, Clostridium migrated from pit mud to fermented grains with the addition of chemokine lactic acid, resulting in the production of acetic acid and butyric acid. The results help to understand the succession mechanism of Clostridium in pit mud, and provide a reference for regulation of lactic acid level in fermented grains during Baijiu fermentation.
Collapse
Affiliation(s)
- Langtao Wu
- Science Center for Future Foods, Jiangnan University, Wuxi 214122, China
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
- Engineering Research Center of Ministry of Education on Food Synthetic Biotechnology, Jiangnan University, Wuxi 214122, China
- Jiangsu Province Engineering Research Center of Food Synthetic Biotechnology, Jiangnan University, Wuxi 214122, China
| | - Jingya Fan
- Science Center for Future Foods, Jiangnan University, Wuxi 214122, China
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
- Engineering Research Center of Ministry of Education on Food Synthetic Biotechnology, Jiangnan University, Wuxi 214122, China
- Jiangsu Province Engineering Research Center of Food Synthetic Biotechnology, Jiangnan University, Wuxi 214122, China
| | - Jian Chen
- Science Center for Future Foods, Jiangnan University, Wuxi 214122, China
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
- Engineering Research Center of Ministry of Education on Food Synthetic Biotechnology, Jiangnan University, Wuxi 214122, China
- Jiangsu Province Engineering Research Center of Food Synthetic Biotechnology, Jiangnan University, Wuxi 214122, China
| | - Fang Fang
- Science Center for Future Foods, Jiangnan University, Wuxi 214122, China
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
- Engineering Research Center of Ministry of Education on Food Synthetic Biotechnology, Jiangnan University, Wuxi 214122, China
- Jiangsu Province Engineering Research Center of Food Synthetic Biotechnology, Jiangnan University, Wuxi 214122, China
- Correspondence: ; Tel.: +86-510-85918310
| |
Collapse
|
12
|
Al-Omari AW, Ramadan Matter I, Hussein Almola A. Molecular study of Enterobacteriaceae bacterium isolated from dishwashers. BIONATURA 2022. [DOI: 10.21931/rb/2022.07.03.28] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
The Enterobacteriaceae family is considered one of the medically essential families in which there is a continuous change in classification, and new species are added to it. In this study, we obtained a novel strain registered in the NCBI under Enterobacteriaceae bacterium strain PRL 4-2, with the accession number MW540823, and the isolate considered unclassified Enterobacteriaceae. The isolate was obtained from dishwashers, which is a mine for many new species and strains due to the unique environmental conditions of this habitat, fluctuation in temperature, use of high temperatures, utilization of cleaning materials as well as humidity and the presence of organic materials, especially in case of neglect of cleaning. The isolate was characterized by its slow growth on culture media and its ability to form biofilms and possess some virulence factors. Its resistance to antibiotics was also studied, as it showed resistance to the antibiotics used in this study. The oddness for this strain is that it showed a different diagnosis when using VITEK (The VITEK 2 system has everything healthcare laboratories need for fast, accurate microbial identification and antibiotic susceptibility testing.) compared to diagnosis using 16S rRNA. As for the taxonomic tree, the closest species was Enterobacter sp. Strain 188. This study supplements a few other studies of this novel species, isolated from different environments. These researches can be integrated to give an itinerary for other studies on the new species and their different capabilities.
Keywords. Enterobacteriaceae bacterium, dishwasher, Enterobacteriaceae bacterium PRL-2, Enterobacter sp., biofilm.
Collapse
Affiliation(s)
- Aisha W. Al-Omari
- Department of Biology, College of Sciences, University of Mosul, Mosul, Iraq
| | | | - Alaa Hussein Almola
- Department of Biology, College of Sciences, University of Mosul, Mosul, Iraq
| |
Collapse
|
13
|
Alías-Villegas C, Fuentes-Romero F, Cuéllar V, Navarro-Gómez P, Soto MJ, Vinardell JM, Acosta-Jurado S. Surface Motility Regulation of Sinorhizobium fredii HH103 by Plant Flavonoids and the NodD1, TtsI, NolR, and MucR1 Symbiotic Bacterial Regulators. Int J Mol Sci 2022; 23:7698. [PMID: 35887044 PMCID: PMC9316994 DOI: 10.3390/ijms23147698] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Revised: 07/08/2022] [Accepted: 07/11/2022] [Indexed: 02/04/2023] Open
Abstract
Bacteria can spread on surfaces to colonize new environments and access more resources. Rhizobia, a group of α- and β-Proteobacteria, establish nitrogen-fixing symbioses with legumes that rely on a complex signal interchange between the partners. Flavonoids exuded by plant roots and the bacterial transcriptional activator NodD control the transcription of different rhizobial genes (the so-called nod regulon) and, together with additional bacterial regulatory proteins (such as TtsI, MucR or NolR), influence the production of different rhizobial molecular signals. In Sinorhizobium fredii HH103, flavonoids and NodD have a negative effect on exopolysaccharide production and biofilm production. Since biofilm formation and motility are often inversely regulated, we have analysed whether flavonoids may influence the translocation of S. fredii HH103 on surfaces. We show that the presence of nod gene-inducing flavonoids does not affect swimming but promotes a mode of surface translocation, which involves both flagella-dependent and -independent mechanisms. This surface motility is regulated in a flavonoid-NodD1-TtsI-dependent manner, relies on the assembly of the symbiotic type 3 secretion system (T3SS), and involves the participation of additional modulators of the nod regulon (NolR and MucR1). To our knowledge, this is the first evidence indicating the participation of T3SS in surface motility in a plant-interacting bacterium. Interestingly, flavonoids acting as nod-gene inducers also participate in the inverse regulation of surface motility and biofilm formation, which could contribute to a more efficient plant colonisation.
Collapse
Affiliation(s)
- Cynthia Alías-Villegas
- Centro Andaluz de Biología del Desarrollo, CSIC/Junta de Andalucía, Departamento de Biología Molecular e Ingeniería Bioquímica, Universidad Pablo de Olavide, 41013 Seville, Spain;
| | - Francisco Fuentes-Romero
- Facultad de Biología, Departamento de Microbiología, Universidad de Sevilla, 41012 Sevilla, Spain; (F.F.-R.); (P.N.-G.)
| | - Virginia Cuéllar
- Estación Experimental del Zaidín, CSIC, Departamento de Biotecnología y Protección Ambiental, 18008 Granada, Spain; (V.C.); (M.J.S.)
| | - Pilar Navarro-Gómez
- Facultad de Biología, Departamento de Microbiología, Universidad de Sevilla, 41012 Sevilla, Spain; (F.F.-R.); (P.N.-G.)
| | - María J. Soto
- Estación Experimental del Zaidín, CSIC, Departamento de Biotecnología y Protección Ambiental, 18008 Granada, Spain; (V.C.); (M.J.S.)
| | - José-María Vinardell
- Facultad de Biología, Departamento de Microbiología, Universidad de Sevilla, 41012 Sevilla, Spain; (F.F.-R.); (P.N.-G.)
| | - Sebastián Acosta-Jurado
- Centro Andaluz de Biología del Desarrollo, CSIC/Junta de Andalucía, Departamento de Biología Molecular e Ingeniería Bioquímica, Universidad Pablo de Olavide, 41013 Seville, Spain;
| |
Collapse
|
14
|
Okaro U, Mou S, Lenkoue G, Williams JA, Bonagofski A, Larson P, Kumar R, DeShazer D. A type IVB pilin influences twitching motility and in vitro adhesion to epithelial cells in Burkholderia pseudomallei. MICROBIOLOGY (READING, ENGLAND) 2022; 168. [PMID: 35293855 PMCID: PMC9558350 DOI: 10.1099/mic.0.001150] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Type IV pili are involved in adhesion, twitching motility, aggregation, biofilm formation and virulence in a variety of Gram-negative bacteria. Burkholderia pseudomallei, the causative agent of melioidosis and a Tier 1 biological select agent, is a Gram-negative bacterium with eight type IV pili-associated loci (TFP1 to TFP8). Most have not been fully characterized. In this study, we investigated BPSS2185, an uncharacterized TFP8 gene that encodes a type IVB pilus protein subunit. Using genetic deletion and complementation analysis in B. pseudomallei JW270, we demonstrate that BPSS2185 plays an important role in twitching motility and adhesion to A549 human alveolar epithelial cells. Compared to JW270, the JW270 ΔBPSS2185 mutant failed to display twitching motility and did not adhere to the epithelial cells. These phenotypes were partially reversed by the complementation of BPSS2185 in the mutant strain. The study also shows that BPSS2185 is expressed only during the onset of mature biofilm formation and at the dispersal of a biofilm, suggesting that the motility characteristic is required to form a biofilm. Our study is the first to suggest that the BPSS2185 gene in TFP8 contributes to twitching motility, adhesion and biofilm formation, indicating that the gene may contribute to B. pseudomallei virulence.
Collapse
Affiliation(s)
- Udoka Okaro
- Bacteriology Division, United States Army Medical Research Institute of Infectious Diseases, Frederick, Maryland, USA
| | - Sherry Mou
- Bacteriology Division, United States Army Medical Research Institute of Infectious Diseases, Frederick, Maryland, USA
| | - Geraldin Lenkoue
- Bacteriology Division, United States Army Medical Research Institute of Infectious Diseases, Frederick, Maryland, USA
| | - Janice A Williams
- Pathology Division, United States Army Medical Research Institute of Infectious Diseases, Frederick, Maryland, USA
| | - Ari Bonagofski
- Pathology Division, United States Army Medical Research Institute of Infectious Diseases, Frederick, Maryland, USA
| | - Peter Larson
- Molecular Biology Division, United States Army Medical Research Institute of Infectious Diseases, Frederick, Maryland, USA
| | - Raina Kumar
- Molecular Biology Division, United States Army Medical Research Institute of Infectious Diseases, Frederick, Maryland, USA
| | - David DeShazer
- Bacteriology Division, United States Army Medical Research Institute of Infectious Diseases, Frederick, Maryland, USA
| |
Collapse
|
15
|
Palma V, Gutiérrez MS, Vargas O, Parthasarathy R, Navarrete P. Methods to Evaluate Bacterial Motility and Its Role in Bacterial–Host Interactions. Microorganisms 2022; 10:microorganisms10030563. [PMID: 35336138 PMCID: PMC8953368 DOI: 10.3390/microorganisms10030563] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Revised: 02/02/2022] [Accepted: 02/06/2022] [Indexed: 11/16/2022] Open
Abstract
Bacterial motility is a widespread characteristic that can provide several advantages for the cell, allowing it to move towards more favorable conditions and enabling host-associated processes such as colonization. There are different bacterial motility types, and their expression is highly regulated by the environmental conditions. Because of this, methods for studying motility under realistic experimental conditions are required. A wide variety of approaches have been developed to study bacterial motility. Here, we present the most common techniques and recent advances and discuss their strengths as well as their limitations. We classify them as macroscopic or microscopic and highlight the advantages of three-dimensional imaging in microscopic approaches. Lastly, we discuss methods suited for studying motility in bacterial–host interactions, including the use of the zebrafish model.
Collapse
Affiliation(s)
- Victoria Palma
- Laboratory of Microbiology and Probiotics, Institute of Nutrition and Food Technology (INTA), University of Chile, El Líbano 5524, Santiago 7830490, Chile; (V.P.); (M.S.G.); (O.V.)
| | - María Soledad Gutiérrez
- Laboratory of Microbiology and Probiotics, Institute of Nutrition and Food Technology (INTA), University of Chile, El Líbano 5524, Santiago 7830490, Chile; (V.P.); (M.S.G.); (O.V.)
- Millennium Science Initiative Program, Milenium Nucleus in the Biology of the Intestinal Microbiota, National Agency for Research and Development (ANID), Moneda 1375, Santiago 8200000, Chile
| | - Orlando Vargas
- Laboratory of Microbiology and Probiotics, Institute of Nutrition and Food Technology (INTA), University of Chile, El Líbano 5524, Santiago 7830490, Chile; (V.P.); (M.S.G.); (O.V.)
| | - Raghuveer Parthasarathy
- Institute of Molecular Biology, University of Oregon, Eugene, OR 97403, USA;
- Department of Physics and Materials Science Institute, University of Oregon, Eugene, OR 97403, USA
| | - Paola Navarrete
- Laboratory of Microbiology and Probiotics, Institute of Nutrition and Food Technology (INTA), University of Chile, El Líbano 5524, Santiago 7830490, Chile; (V.P.); (M.S.G.); (O.V.)
- Millennium Science Initiative Program, Milenium Nucleus in the Biology of the Intestinal Microbiota, National Agency for Research and Development (ANID), Moneda 1375, Santiago 8200000, Chile
- Correspondence:
| |
Collapse
|
16
|
Surveying a Swarm: Experimental Techniques to Establish and Examine Bacterial Collective Motion. Appl Environ Microbiol 2021; 88:e0185321. [PMID: 34878816 DOI: 10.1128/aem.01853-21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The survival and successful spread of many bacterial species hinges on their mode of motility. One of the most distinct of these is swarming, a collective form of motility where a dense consortium of bacteria employ flagella to propel themselves across a solid surface. Surface environments pose unique challenges, derived from higher surface friction/tension and insufficient hydration. Bacteria have adapted by deploying an array of mechanisms to overcome these challenges. Beyond allowing bacteria to colonize new terrain in the absence of bulk liquid, swarming also bestows faster speeds and enhanced antibiotic resistance to the collective. These crucial attributes contribute to the dissemination, and in some cases pathogenicity, of an array of bacteria. This mini-review highlights; 1) aspects of swarming motility that differentiates it from other methods of bacterial locomotion. 2) Facilitatory mechanisms deployed by diverse bacteria to overcome different surface challenges. 3) The (often difficult) approaches required to cultivate genuine swarmers. 4) The methods available to observe and assess the various facets of this collective motion, as well as the features exhibited by the population as a whole.
Collapse
|
17
|
Ióca LP, Dai Y, Kunakom S, Diaz‐Espinosa J, Krunic A, Crnkovic CM, Orjala J, Sanchez LM, Ferreira AG, Berlinck RGS, Eustáquio AS. A Family of Nonribosomal Peptides Modulate Collective Behavior in
Pseudovibrio
Bacteria Isolated from Marine Sponges**. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202017320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Laura P. Ióca
- Department of Pharmaceutical Sciences College of Pharmacy University of Illinois at Chicago Chicago IL 60607 USA
- Center for Biomolecular Sciences College of Pharmacy University of Illinois at Chicago Chicago IL 60607 USA
- Instituto de Química de São Carlos Universidade de São Paulo São Carlos SP 13560-970 Brazil
| | - Yitao Dai
- Department of Pharmaceutical Sciences College of Pharmacy University of Illinois at Chicago Chicago IL 60607 USA
- Center for Biomolecular Sciences College of Pharmacy University of Illinois at Chicago Chicago IL 60607 USA
| | - Sylvia Kunakom
- Department of Pharmaceutical Sciences College of Pharmacy University of Illinois at Chicago Chicago IL 60607 USA
- Center for Biomolecular Sciences College of Pharmacy University of Illinois at Chicago Chicago IL 60607 USA
| | - Jennifer Diaz‐Espinosa
- Department of Pharmaceutical Sciences College of Pharmacy University of Illinois at Chicago Chicago IL 60607 USA
- Center for Biomolecular Sciences College of Pharmacy University of Illinois at Chicago Chicago IL 60607 USA
| | - Aleksej Krunic
- Department of Pharmaceutical Sciences College of Pharmacy University of Illinois at Chicago Chicago IL 60607 USA
| | - Camila M. Crnkovic
- Department of Pharmaceutical Sciences College of Pharmacy University of Illinois at Chicago Chicago IL 60607 USA
- Center for Biomolecular Sciences College of Pharmacy University of Illinois at Chicago Chicago IL 60607 USA
| | - Jimmy Orjala
- Department of Pharmaceutical Sciences College of Pharmacy University of Illinois at Chicago Chicago IL 60607 USA
- Center for Biomolecular Sciences College of Pharmacy University of Illinois at Chicago Chicago IL 60607 USA
| | - Laura M. Sanchez
- Department of Pharmaceutical Sciences College of Pharmacy University of Illinois at Chicago Chicago IL 60607 USA
| | - Antonio G. Ferreira
- Departamento de Química Universidade Federal de São Carlos São Carlos SP 13565-905 Brazil
| | - Roberto G. S. Berlinck
- Instituto de Química de São Carlos Universidade de São Paulo São Carlos SP 13560-970 Brazil
| | - Alessandra S. Eustáquio
- Department of Pharmaceutical Sciences College of Pharmacy University of Illinois at Chicago Chicago IL 60607 USA
- Center for Biomolecular Sciences College of Pharmacy University of Illinois at Chicago Chicago IL 60607 USA
| |
Collapse
|
18
|
Ióca LP, Dai Y, Kunakom S, Diaz-Espinosa J, Krunic A, Crnkovic CM, Orjala J, Sanchez LM, Ferreira AG, Berlinck RGS, Eustáquio AS. A Family of Nonribosomal Peptides Modulate Collective Behavior in Pseudovibrio Bacteria Isolated from Marine Sponges*. Angew Chem Int Ed Engl 2021; 60:15891-15898. [PMID: 33961724 PMCID: PMC8269750 DOI: 10.1002/anie.202017320] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 04/01/2021] [Indexed: 11/08/2022]
Abstract
Although swarming motility and biofilms are opposed collective behaviors, both contribute to bacterial survival and host colonization. Pseudovibrio bacteria have attracted attention because they are part of the microbiome of healthy marine sponges. Two-thirds of Pseudovibrio genomes contain a member of a nonribosomal peptide synthetase-polyketide synthase gene cluster family, which is also found sporadically in Pseudomonas pathogens of insects and plants. After developing reverse genetics for Pseudovibrio, we isolated heptapeptides with an ureido linkage and related nonadepsipeptides we termed pseudovibriamides A and B, respectively. A combination of genetics and imaging mass spectrometry experiments showed heptapetides were excreted, promoting motility and reducing biofilm formation. In contrast to lipopeptides widely known to affect motility/biofilms, pseudovibriamides are not surfactants. Our results expand current knowledge on metabolites mediating bacterial collective behavior.
Collapse
Affiliation(s)
- Laura P. Ióca
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Illinois at Chicago, Chicago, IL 60607, USA
- Center for Biomolecular Sciences, College of Pharmacy, University of Illinois at Chicago, Chicago, IL 60607, USA
- Instituto de Química de São Carlos, Universidade de São Paulo, São Carlos, SP 13560-970, Brazil
| | - Yitao Dai
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Illinois at Chicago, Chicago, IL 60607, USA
- Center for Biomolecular Sciences, College of Pharmacy, University of Illinois at Chicago, Chicago, IL 60607, USA
| | - Sylvia Kunakom
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Illinois at Chicago, Chicago, IL 60607, USA
- Center for Biomolecular Sciences, College of Pharmacy, University of Illinois at Chicago, Chicago, IL 60607, USA
| | - Jennifer Diaz-Espinosa
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Illinois at Chicago, Chicago, IL 60607, USA
- Center for Biomolecular Sciences, College of Pharmacy, University of Illinois at Chicago, Chicago, IL 60607, USA
| | - Aleksej Krunic
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Illinois at Chicago, Chicago, IL 60607, USA
| | - Camila M. Crnkovic
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Illinois at Chicago, Chicago, IL 60607, USA
- Center for Biomolecular Sciences, College of Pharmacy, University of Illinois at Chicago, Chicago, IL 60607, USA
| | - Jimmy Orjala
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Illinois at Chicago, Chicago, IL 60607, USA
- Center for Biomolecular Sciences, College of Pharmacy, University of Illinois at Chicago, Chicago, IL 60607, USA
| | - Laura M. Sanchez
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Illinois at Chicago, Chicago, IL 60607, USA
| | - Antonio G. Ferreira
- Departamento de Química, Universidade Federal de São Carlos, São Carlos, SP 13565-905, Brazil
| | - Roberto G. S. Berlinck
- Instituto de Química de São Carlos, Universidade de São Paulo, São Carlos, SP 13560-970, Brazil
| | - Alessandra S. Eustáquio
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Illinois at Chicago, Chicago, IL 60607, USA
- Center for Biomolecular Sciences, College of Pharmacy, University of Illinois at Chicago, Chicago, IL 60607, USA
| |
Collapse
|
19
|
Analyzing the Effect of Strigolactones on the Motility Behavior of Rhizobia. Methods Mol Biol 2021. [PMID: 34028681 DOI: 10.1007/978-1-0716-1429-7_8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
Abstract
In the Rhizobium-legume symbiosis, strigolactones (SLs) promote root nodule formation; however, the exact mechanism underlying this positive effect remains unknown. The recent finding that an SL receptor legume mutant shows a wild-type nodulation phenotype suggests that SLs influence the symbiosis by acting on the bacterial partner. In agreement with this, the application of the synthetic SL analog GR24 on the alfalfa symbiont Sinorhizobium (Ensifer) meliloti has been shown to stimulate swarming, a specialized bacterial surface motility, which could influence infection of legumes by Rhizobia. Surface motility assays for many bacteria, and particularly for Rhizobia, are challenging. The establishment of protocols to study bacterial surface motility is key to decipher the role of SLs as rhizosphere cues for rhizobacteria. In this chapter, we describe a set of protocols implemented to study the different types of motility exhibited by S. meliloti.
Collapse
|
20
|
Lau TTV, Puah SM, Tan JAMA, Puthucheary SD, Chua KH. Characterization of the relationship between polar and lateral flagellar genes in clinical Aeromonas dhakensis: phenotypic, genetic and biochemical analyses. Braz J Microbiol 2021; 52:517-529. [PMID: 33768508 DOI: 10.1007/s42770-021-00457-8] [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: 04/20/2020] [Accepted: 02/23/2021] [Indexed: 11/25/2022] Open
Abstract
Flagellar-mediated motility is a crucial virulence factor in many bacterial species. A dual flagellar system has been described in aeromonads; however, there is no flagella-related study in the emergent human pathogen Aeromonas dhakensis. Using 46 clinical A. dhakensis, phenotypic motility, genotypic characteristics (flagellar genes and sequence types), biochemical properties and their relationship were investigated in this study. All 46 strains showed swimming motility at 30 °C in 0.3% Bacto agar and carried the most prevalent 6 polar flagellar genes cheA, flgE, flgG, flgH, flgL, and flgN. On the contrary, only 18 strains (39%) demonstrated swarming motility on 0.5% Eiken agar at 30 °C and they harbored 11 lateral flagellar genes lafB, lafK, lafS, lafT, lafU, flgCL, flgGL, flgNL, fliEL, fliFL, and fliGL. No association was found between biochemical properties and motility phenotypes. Interestingly, a significant association between swarming and strains isolated from pus was observed (p = 0.0171). Three strains 187, 277, and 289 isolated from pus belonged to novel sequence types (ST522 and ST524) exhibited fast swimming and swarming profiles, and they harbored > 90% of the flagellar genes tested. Our findings provide a fundamental understanding of flagellar-mediated motility in A. dhakensis.
Collapse
Affiliation(s)
- Tien-Tien Vicky Lau
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Suat-Moi Puah
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | | | - S D Puthucheary
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Kek-Heng Chua
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia.
| |
Collapse
|
21
|
Transient surface hydration impacts biogeography and intercellular interactions of non-motile bacteria. Appl Environ Microbiol 2021; 87:AEM.03067-20. [PMID: 33579687 PMCID: PMC8091113 DOI: 10.1128/aem.03067-20] [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: 11/20/2022] Open
Abstract
There are many hydrated surface niches that are neither static nor continuously flowing that are colonized by microbes such as bacteria. Such periodic hydrodynamic regimes are distinct from aquatic systems where microbial dissemination is reasonably predicted by assuming continuous flow or static systems where motile microbes largely control their own fate. Here we show how non-motile bacteria exhibit rapid, dispersive bursts of movement over surfaces using transient confluent hydration from the environment, which we term "surface hydrodispersion" where cells traverse thousands of cell lengths within minutes. The fraction of the population disseminated by surface hydrodispersion is small-on order of 1 cell per million. Thus, surface hydrodispersion can promote isolated distribution of single cells, which is unlike other characterized active and passive surface motilities. We describe this translocation using a continuous time random walk modeling approach and find in computational simulations that transient fluid accumulation, dilution, and gravitational pull are the contributing factors. Surface hydrodispersion, consistent with advection, is unlike simple colony expansion as it dramatically alters spatial relationships, shown here with Staphylococcus aureus, which becomes increasingly virulent when isolated from Corynebacterium striatum Surface hydrodispersion of non-motile bacteria exploiting transient fluid availability and gravity is a mechanism that can result in sporadic and sudden shifts in microbial community behavior. To better understand how this movement can impact biogeography on the millimeter scale, this work describes a system for study of primary factors behind this movement as well as a stochastic model describing this dispersal.Importance: Understanding the dynamics within microbiome communities is a challenge. Knowledge of phylogeny and spatial arrangement has led to increased understanding of numerous polymicrobial communities yet, these snapshots do not convey the dynamics of populations over time. The actual biogeography of any microbiome controls the potential interactions, governing any possible antagonistic or synergistic behavior. Accordingly, a shift in biogeography can enable new behavior. Little is known about the movement mechanisms of "non-motile" microbes. Here we characterize a universal means of movement we term hydrodispersion where non-motile bacteria are transported thousands of cell lengths in minutes. We show that only a small fraction of the population is translocated by hydrodispersion and describe this movement further using a random-walk mathematical model approach in silico We demonstrate the importance of hydrodispersion by showing that Staphylococcus aureus can separate from a coculture inoculation with Corynebacterium striatum thus permitting transition to a more virulent state.
Collapse
|
22
|
Ma H, Bell J, Chen W, Mani S, Tang JX. An expanding bacterial colony forms a depletion zone with growing droplets. SOFT MATTER 2021; 17:2315-2326. [PMID: 33480951 PMCID: PMC8608367 DOI: 10.1039/d0sm01348j] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Many species of bacteria have developed effective means to spread on solid surfaces. This study focuses on the expansion of Pseudomonas aeruginosa on an agar gel surface under conditions of minimal evaporation. We report the occurrence and spread of a depletion zone within an expanded colony, where the bacteria laden film becomes thinner. The depletion zone is colocalized with a higher concentration of rhamnolipids, the biosurfactants that are produced by the bacteria and accumulate in the older region of the colony. With continued growth in population, dense bacterial droplets occur and coalesce in the depletion zone, displaying remarkable fluid dynamic behavior. Whereas expansion of a central depletion zone requires activities of live bacteria, new zones can be seeded elsewhere by adding rhamnolipids. These depletion zones due to the added surfactants expand quickly, even on plates covered by bacteria that have been killed by ultraviolet light. We explain the observed properties based on considerations of bacterial growth and secretion, osmotic swelling, fluid volume expansion, interfacial fluid dynamics involving Marangoni and capillary flows, and cell-cell cohesion.
Collapse
Affiliation(s)
- Hui Ma
- Physics Department, Brown University, Providence, RI, USA.
| | - Jordan Bell
- Physics Department, Brown University, Providence, RI, USA.
| | - Weijie Chen
- Physics Department, Brown University, Providence, RI, USA. and Department of Medicine, Genetics and Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Sridhar Mani
- Department of Medicine, Genetics and Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Jay X Tang
- Physics Department, Brown University, Providence, RI, USA.
| |
Collapse
|
23
|
He Y, Wang S, Wang K, Zhou J, Han Z, Sun F. Analysis of Secreted Proteins and Potential Virulence via the ICEs-Mediated Pathway of the Foodborne Pathogen Vibrio parahaemolyticus. Front Microbiol 2021; 12:612166. [PMID: 33763038 PMCID: PMC7982893 DOI: 10.3389/fmicb.2021.612166] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Accepted: 01/25/2021] [Indexed: 11/13/2022] Open
Abstract
Vibrio parahaemolyticus uses bacterial secretion systems and integrative and conjugative elements (ICEs) to induce various diseases and to adapt to harsh environments, respectively. Information pertaining to the identity of secreted proteins and functional characterization of ICEs has been previously reported, but the relationship between these elements remains unclear. Herein we investigated secreted proteins of V. parahaemolyticus strains JHY20 and JHY20△ICE using two-dimensional gel electrophoresis and LC-MS/MS, which led to the identification of an ICE-associated secreted protein – dihydrolipoamide dehydrogenase (DLDH). Considering the data related to its physical and biochemical characterization, we predicted that DLDH is a novel immunogenic protein and associated with virulence in JHY20. Our findings indicate a potential relationship between ICE-associated transport and secreted proteins and shed light on the function of such transport mechanisms. We believe that our data should enhance our understanding of mobile genetic elements.
Collapse
Affiliation(s)
- Yu He
- College of Food (Biotechnology) Engineering, Xuzhou University of Technology, Xuzhou, China.,Key Construction Laboratory of Food Resources Development and the Quality Safety in Jiangsu, Xuzhou University of Technology, Xuzhou, China
| | - Shuai Wang
- College of Food (Biotechnology) Engineering, Xuzhou University of Technology, Xuzhou, China.,Key Construction Laboratory of Food Resources Development and the Quality Safety in Jiangsu, Xuzhou University of Technology, Xuzhou, China
| | - Kaiwen Wang
- College of Food (Biotechnology) Engineering, Xuzhou University of Technology, Xuzhou, China
| | - Jinwei Zhou
- College of Food (Biotechnology) Engineering, Xuzhou University of Technology, Xuzhou, China.,Key Construction Laboratory of Food Resources Development and the Quality Safety in Jiangsu, Xuzhou University of Technology, Xuzhou, China
| | - Zhi Han
- School of Energy and Power Engineering, Jiangsu University, Zhenjiang, China
| | - Fengjiao Sun
- Logistics & Security Department, Shanghai Civil Aviation College, Shanghai, China
| |
Collapse
|
24
|
A Framework for the Selection of Plant Growth-Promoting Rhizobacteria Based on Bacterial Competence Mechanisms. Appl Environ Microbiol 2020; 86:AEM.00760-20. [PMID: 32358015 PMCID: PMC7357491 DOI: 10.1128/aem.00760-20] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Accepted: 04/28/2020] [Indexed: 01/28/2023] Open
Abstract
Numerous plant growth-promoting rhizobacteria (PGPR) have been inoculated into the soil with the aim of improving the supply of nutrients to crop plants and decreasing the requirement of chemical fertilizers. However, sometimes these microbes fail to competitively colonize the plant roots and rhizosphere. Hence, the plant growth promotion effect is not observed. Here, we describe a new screening strategy aiming at the selection of more competent PGPR. We evaluated bacterial phenotypes related to plant growth promotion, colonization, and persistence. Our results demonstrated that despite the fact that our Rhizobium sp. strains successfully solubilized phosphorus and produced siderophores, their abilities to spread over surfaces, resist hydrogen peroxide, and form biofilms varied. Additionally, a multicriteria decision analysis was used to analyze the data that originated from bacterial physiological characterizations. This analysis allowed us to innovatively evaluate each strain as a whole and compare the performances of the strains under hypothetical scenarios of bacterial-trait requirements. The use of plant growth-promoting rhizobacteria (PGPR) is increasingly meaningful for the development of more environmentally friendly agricultural practices. However, often the PGPR strains selected in the laboratory fail to confer the expected beneficial effects when evaluated in plant experiments. Insufficient rhizosphere colonization is pointed out as one of the causes. With the aim of minimizing this inconsistency, we propose that besides studying plant growth promotion traits (PGP), the screening strategy should include evaluation of the microbial phenotypes required for colonization and persistence. As a model, we carried out this strategy in three Rhizobium sp. strains that showed phosphorus solubilization ability and production of siderophores. All strains displayed colonization phenotypes like surface spreading, resistance to hydrogen peroxide, and formed biofilms. Regarding their ability to persist, biofilm formation was observed to be influenced by pH and the phosphorus nutrient provided in the growth media. Differences in the competence of the strains to use several carbon substrates were also detected. As part of our framework, we compared the phenotypic characteristics of the strains in a quantitative manner. The data analysis was integrated using a multicriteria decision analysis (MCDA). All our results were scored, weighted, and grouped as relevant for PGP, colonization, or persistence. MCDA demonstrated that, when the phenotypes related to PGP and colonization are weighted over those for persistence, strain B02 performs better than the other two Rhizobium sp. strains. The use of our framework could assist the selection of more competent strains to be tested in greenhouse and field trials. IMPORTANCE Numerous plant growth-promoting rhizobacteria (PGPR) have been inoculated into the soil with the aim of improving the supply of nutrients to crop plants and decreasing the requirement of chemical fertilizers. However, sometimes these microbes fail to competitively colonize the plant roots and rhizosphere. Hence, the plant growth promotion effect is not observed. Here, we describe a new screening strategy aiming at the selection of more competent PGPR. We evaluated bacterial phenotypes related to plant growth promotion, colonization, and persistence. Our results demonstrated that despite the fact that our Rhizobium sp. strains successfully solubilized phosphorus and produced siderophores, their abilities to spread over surfaces, resist hydrogen peroxide, and form biofilms varied. Additionally, a multicriteria decision analysis was used to analyze the data that originated from bacterial physiological characterizations. This analysis allowed us to innovatively evaluate each strain as a whole and compare the performances of the strains under hypothetical scenarios of bacterial-trait requirements.
Collapse
|
25
|
Collective Dynamics of Model Pili-Based Twitcher-Mode Bacilliforms. Sci Rep 2020; 10:10747. [PMID: 32612117 PMCID: PMC7330051 DOI: 10.1038/s41598-020-67212-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2020] [Accepted: 05/27/2020] [Indexed: 11/29/2022] Open
Abstract
Pseudomonas aeruginosa, like many bacilliforms, are not limited only to swimming motility but rather possess many motility strategies. In particular, twitching-mode motility employs hair-like pili to transverse moist surfaces with a jittery irregular crawl. Twitching motility plays a critical role in redistributing cells on surfaces prior to and during colony formation. We combine molecular dynamics and rule-based simulations to study twitching-mode motility of model bacilliforms and show that there is a critical surface coverage fraction at which collective effects arise. Our simulations demonstrate dynamic clustering of twitcher-type bacteria with polydomains of local alignment that exhibit spontaneous correlated motions, similar to rafts in many bacterial communities.
Collapse
|
26
|
Morabe ML, McCarter LL. Vibrio parahaemolyticus FcrX, a Fur-controlled regulator that inhibits repression by Fur. Mol Microbiol 2020; 114:77-92. [PMID: 32096286 DOI: 10.1111/mmi.14497] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Revised: 02/20/2020] [Accepted: 02/23/2020] [Indexed: 12/15/2022]
Abstract
Iron is an essential nutrient for most organisms, but its limited availability and inherent toxicity necessitate the strict regulation of iron homeostasis. In bacteria, iron starvation affects a broad range of phenotypes including virulence, motility and biofilm formation. For Vibrio parahaemolyticus, a marine bacterium and pathogen, iron limitation is a signal modulating swarmer cell differentiation. In this work, we show the iron regulation of swarming works through the ferric uptake regulator protein Fur. We identified a new Fur-controlled regulator that is upregulated upon iron starvation. FcrX is a 144-amino acid protein containing a domain of unknown function (DUF2753) with three tetratricopeptide repeats. We found that overexpressing fcrX+ was sufficient to induce swarming, luminescence and iron uptake gene expression in multiple Vibrio species; furthermore, ectopic expression increased the transcription of a Fur-controlled gene in Escherichia coli. FcrX production increased intracellular iron. Thus, the overexpression of fcrX+ phenocopied a fur mutant and may prove a generally useful tool to ectopically derepress the Fur regulon. Both V. parahaemolyticus and E. coli Fur interacted with FcrX, and this interaction was altered by iron availability. These data support a model in which this new regulator of iron homeostasis limits the repressive action of Fur.
Collapse
Affiliation(s)
- Maria L Morabe
- Department of Microbiology and Immunology, University of Iowa, Iowa City, IA, USA
| | - Linda L McCarter
- Department of Microbiology and Immunology, University of Iowa, Iowa City, IA, USA
| |
Collapse
|
27
|
Brescia F, Marchetti-Deschmann M, Musetti R, Perazzolli M, Pertot I, Puopolo G. The rhizosphere signature on the cell motility, biofilm formation and secondary metabolite production of a plant-associated Lysobacter strain. Microbiol Res 2020; 234:126424. [PMID: 32036275 DOI: 10.1016/j.micres.2020.126424] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Revised: 01/10/2020] [Accepted: 01/26/2020] [Indexed: 12/15/2022]
Abstract
Lysobacter spp. are common bacterial inhabitants of the rhizosphere of diverse plant species. However, the impact of the rhizosphere conditions on their physiology is still relatively understudied. To provide clues on the behaviour of Lysobacter spp. in this ecological niche, we investigated the physiology of L. capsici AZ78 (AZ78), a biocontrol strain isolated from tobacco rhizosphere, on a common synthetic growth medium (LBA) and on a growth medium containing components of the plant rhizosphere (RMA). The presence of a halo surrounding the AZ78 colony on RMA was a first visible effect related to differences in growth medium composition and it corresponded to the formation of a large outer ring. The lower quantity of nutrients available in RMA as compared with LBA was associated to a higher expression of a gene encoding cAMP-receptor-like protein (Clp), responsible for cell motility and biofilm formation regulation. AZ78 cells on RMA were motile, equipped with cell surface appendages and organised in small groups embedded in a dense layer of fibrils. Metabolic profiling by mass spectrometry imaging revealed increased diversity of analytes produced by AZ78 on RMA as compared with LBA. In particular, putative cyclic lipodepsipeptides, polycyclic tetramate macrolactams, cyclic macrolactams and other putative secondary metabolites with antibiotic activity were identified. Overall, the results obtained in this study shed a light on AZ78 potential to thrive in the rhizosphere by its ability to move, form biofilm and release secondary metabolites.
Collapse
Affiliation(s)
- Francesca Brescia
- Department of Sustainable Agro-ecosystems and Bioresources, Research and Innovation Centre, Fondazione Edmund Mach, Via E. Mach 1, 38010, San Michele all'Adige, Italy; PhD school in Agricultural Science and Biotechnology, Department of Agricultural, Food, Environmental and Animal Sciences, University of Udine, Udine, Italy
| | - Martina Marchetti-Deschmann
- Institute of Chemical Technologies and Analytics, TU Wien (Vienna University of Technology), Vienna, 1060, Austria
| | - Rita Musetti
- Department of Agricultural, Food, Environmental and Animal Sciences, University of Udine, Udine, 33100, Italy
| | - Michele Perazzolli
- Department of Sustainable Agro-ecosystems and Bioresources, Research and Innovation Centre, Fondazione Edmund Mach, Via E. Mach 1, 38010, San Michele all'Adige, Italy; Center Agriculture Food Environment (C3A), University of Trento, Via E. Mach 1, 38010, San Michele all'Adige, Italy
| | - Ilaria Pertot
- Department of Sustainable Agro-ecosystems and Bioresources, Research and Innovation Centre, Fondazione Edmund Mach, Via E. Mach 1, 38010, San Michele all'Adige, Italy; Center Agriculture Food Environment (C3A), University of Trento, Via E. Mach 1, 38010, San Michele all'Adige, Italy
| | - Gerardo Puopolo
- Department of Sustainable Agro-ecosystems and Bioresources, Research and Innovation Centre, Fondazione Edmund Mach, Via E. Mach 1, 38010, San Michele all'Adige, Italy; Center Agriculture Food Environment (C3A), University of Trento, Via E. Mach 1, 38010, San Michele all'Adige, Italy.
| |
Collapse
|
28
|
Abstract
Bacteria can migrate in groups of flagella-driven cells over semisolid surfaces. This coordinated form of motility is called swarming behavior. Swarming is associated with enhanced virulence and antibiotic resistance of various human pathogens and may be considered as favorable adaptation to the diverse challenges that microbes face in rapidly changing environments. Consequently, the differentiation of motile swarmer cells is tightly regulated and involves multi-layered signaling networks. Controlling swarming behavior is of major interest for the development of novel anti-infective strategies. In addition, compounds that block swarming represent important tools for more detailed insights into the molecular mechanisms of the coordination of bacterial population behavior. Over the past decades, there has been major progress in the discovery of small-molecule modulators and mechanisms that allow selective inhibition of swarming behavior. Herein, an overview of the achievements in the field and future directions and challenges will be presented.
Collapse
Affiliation(s)
- Sina Rütschlin
- Department of ChemistryKonstanz Research, School Chemical Biology, ZukunftskollegUniversity of Konstanz78457KonstanzGermany
| | - Thomas Böttcher
- Department of ChemistryKonstanz Research, School Chemical Biology, ZukunftskollegUniversity of Konstanz78457KonstanzGermany
| |
Collapse
|
29
|
Chawla R, Gupta R, Lele TP, Lele PP. A Skeptic's Guide to Bacterial Mechanosensing. J Mol Biol 2020; 432:523-533. [PMID: 31629771 PMCID: PMC7002054 DOI: 10.1016/j.jmb.2019.09.004] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Revised: 09/03/2019] [Accepted: 09/11/2019] [Indexed: 12/28/2022]
Abstract
Surface sensing in bacteria is a precursor to the colonization of biotic and abiotic surfaces, and an important cause of drug resistance and virulence. As a motile bacterium approaches and adheres to a surface from the bulk fluid, the mechanical forces that act on it change. Bacteria are able to sense these changes in the mechanical load through a process termed mechanosensing. Bacterial mechanosensing has featured prominently in recent literature as playing a key role in surface sensing. However, the changes in mechanical loads on different parts of the cell at a surface vary in magnitudes as well as in signs. This confounds the determination of a causal relationship between the activation of specific mechanosensors and surface sensing. Here, we explain how contrasting mechanical stimuli arise on a surface-adherent cell and how known mechanosensors respond to these stimuli. The evidence for mechanosensing in select bacterial species is reinterpreted, with a focus on mechanosensitive molecular motors. We conclude with proposed criteria that bacterial mechanosensors must satisfy to successfully mediate surface sensing.
Collapse
Affiliation(s)
- Ravi Chawla
- Artie McFerrin Department of Chemical Engineering, Texas A&M University, College Station, TX, USA
| | - Rachit Gupta
- Artie McFerrin Department of Chemical Engineering, Texas A&M University, College Station, TX, USA
| | - Tanmay P Lele
- Department of Chemical Engineering, University of Florida, Gainesville, Fl, USA
| | - Pushkar P Lele
- Artie McFerrin Department of Chemical Engineering, Texas A&M University, College Station, TX, USA.
| |
Collapse
|
30
|
Jayathilake PG, Li B, Zuliani P, Curtis T, Chen J. Modelling bacterial twitching in fluid flows: a CFD-DEM approach. Sci Rep 2019; 9:14540. [PMID: 31601892 PMCID: PMC6787227 DOI: 10.1038/s41598-019-51101-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Accepted: 09/25/2019] [Indexed: 12/11/2022] Open
Abstract
Bacterial habitats are often associated with fluid flow environments. Bacterial twitching is important for initial bacterial colonization and biofilm formation. The existing research about bacteria twitching is largely experimental orientated. There is a lack of models of twitching motility of bacteria in shear flows, which could provide fundamental understanding about how bacterial twitching would be affected by bacteria associated properties such as number of pili and their distribution on the cell body and environmental factors such as flow and surface patterns. In this work, a three-dimensional modelling approach of Computational Fluid Dynamics (CFD) coupled with the Discrete Element Method (DEM) proposed to study bacterial twitching on flat and groove surfaces under shear flow conditions. Rod-shaped bacteria are modelled as groups of spherical particles and Type IV pili attached to bacteria are modelled as dynamic springs which can elongate, retract, attach and detach. The CFD-DEM model of rod-shape bacteria is validated against orbiting of immotile bacteria in shear flows. The effects of fluid flow rate and surface topography on twitching motility are studied. The model can successfully predict upstream twitching motility of rod-shaped bacteria in shear flows. Our model can predict that there would be an optimal range of wall shear stress in which bacterial upstream twitching is most efficient. The results also indicate that when bacteria twitch on groove surfaces, they are likely to accumulate around the downstream side of the groove walls.
Collapse
Affiliation(s)
- Pahala Gedara Jayathilake
- School of Engineering, Newcastle University, NE17RU, Newcastle upon Tyne, United Kingdom.
- Department of Oncology, University of Oxford, Oxford, UK.
| | - Bowen Li
- School of Computing, Newcastle University, NE17RU, Newcastle upon Tyne, United Kingdom
| | - Paolo Zuliani
- School of Computing, Newcastle University, NE17RU, Newcastle upon Tyne, United Kingdom
| | - Tom Curtis
- School of Engineering, Newcastle University, NE17RU, Newcastle upon Tyne, United Kingdom
| | - Jinju Chen
- School of Engineering, Newcastle University, NE17RU, Newcastle upon Tyne, United Kingdom.
| |
Collapse
|
31
|
Madukoma CS, Liang P, Dimkovikj A, Chen J, Lee SW, Chen DZ, Shrout JD. Single Cells Exhibit Differing Behavioral Phases during Early Stages of Pseudomonas aeruginosa Swarming. J Bacteriol 2019; 201:e00184-19. [PMID: 31308071 PMCID: PMC6755744 DOI: 10.1128/jb.00184-19] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Accepted: 07/09/2019] [Indexed: 12/23/2022] Open
Abstract
Pseudomonas aeruginosa is among the many bacteria that swarm, where groups of cells coordinate to move over surfaces. It has been challenging to determine the behavior of single cells within these high-cell-density swarms. To track individual cells within P. aeruginosa swarms, we imaged a fluorescently labeled subset of the larger population. Single cells at the advancing swarm edge varied in their motility dynamics as a function of time. From these data, we delineated four phases of early swarming prior to the formation of the tendril fractals characteristic of P. aeruginosa swarming by collectively considering both micro- and macroscale data. We determined that the period of greatest single-cell motility does not coincide with the period of greatest collective swarm expansion. We also noted that flagellar, rhamnolipid, and type IV pilus motility mutants exhibit substantially less single-cell motility than the wild type.IMPORTANCE Numerous bacteria exhibit coordinated swarming motion over surfaces. It is often challenging to assess the behavior of single cells within swarming communities due to the limitations of identifying, tracking, and analyzing the traits of swarming cells over time. Here, we show that the behavior of Pseudomonas aeruginosa swarming cells can vary substantially in the earliest phases of swarming. This is important to establish that dynamic behaviors should not be assumed to be constant over long periods when predicting and simulating the actions of swarming bacteria.
Collapse
Affiliation(s)
- Chinedu S Madukoma
- Department of Civil and Environmental Engineering and Earth Sciences, University of Notre Dame, Notre Dame, Indiana, USA
| | - Peixian Liang
- Department of Computer Science and Engineering, University of Notre Dame, Notre Dame, Indiana, USA
| | - Aleksandar Dimkovikj
- Department of Civil and Environmental Engineering and Earth Sciences, University of Notre Dame, Notre Dame, Indiana, USA
| | - Jianxu Chen
- Department of Computer Science and Engineering, University of Notre Dame, Notre Dame, Indiana, USA
| | - Shaun W Lee
- Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, USA
| | - Danny Z Chen
- Department of Computer Science and Engineering, University of Notre Dame, Notre Dame, Indiana, USA
| | - Joshua D Shrout
- Department of Civil and Environmental Engineering and Earth Sciences, University of Notre Dame, Notre Dame, Indiana, USA
- Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, USA
| |
Collapse
|
32
|
Melchior K, Moreira CG. Novel non-flagellated surface motility mediated by chemical signaling in Citrobacter rodentium. Braz J Microbiol 2019; 50:881-886. [PMID: 31456170 DOI: 10.1007/s42770-019-00123-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Accepted: 07/26/2019] [Indexed: 01/16/2023] Open
Abstract
Enterohemorrhagic (EHEC) and enteropathogenic Escherichia coli (EPEC) are human intestinal pathogens of clinical importance and their mechanism of pathogenicity is widely studied. However, both EHEC and EPEC poorly infect mice, whereas they do not develop important characteristics of the disease, hindering studies about mechanisms of virulence in vivo. Citrobacter rodentium exhibits high similarity of its genes with these human pathogens, including the island of pathogenicity Locus of Enterocyte Effacement (LEE). Therefore, C. rodentium becomes an alternative in vivo model for microorganisms that harbor LEE. The QseC directly regulates LEE as well as virulence mechanisms on these pathogens. Here, we report a novel surface motility in C. rodentium QseC-mediated in this non-flagellated bacterium. Moreover, we show norepinephrine and ethanolamine act as environmental signals in this movement. Hence, this study clarifies a novel role of the sensor QseC in completely unreported motility process of C. rodentium.
Collapse
Affiliation(s)
- Karine Melchior
- UNESP - São Paulo State University, Rod. Araraquara-Jaú, Km 01, Araraquara, SP, Brazil
| | | |
Collapse
|
33
|
Abstract
The fundamental motile behavior of E. coli is a random walk, where straight “runs” are punctuated by “tumbles.” This behavior, conferred by the chemotaxis signaling system, is used to track chemical gradients in liquid. Our study results show that when migrating collectively on surfaces, E. coli modifies its chemosensory physiology to decrease its tumble bias (and hence to increase run durations) by post-transcriptional changes that alter the levels of a key signaling protein. We speculate that the low tumble bias may contribute to the observed Lévy walk (LW) trajectories within the swarm, where run durations have a power law distribution. In animals, LW patterns are hypothesized to maximize searches in unpredictable environments. Swarming bacteria face several challenges while moving collectively over a surface—maintaining cohesion, overcoming constraints imposed by a physical substrate, searching for nutrients as a group, and surviving lethal levels of antimicrobials. The altered chemosensory behavior that we describe in this report may help with these challenges. Many flagellated bacteria “swarm” over a solid surface as a dense consortium. In different bacteria, swarming is facilitated by several alterations such as those corresponding to increased flagellum numbers, special stator proteins, or secreted surfactants. We report here a change in the chemosensory physiology of swarming Escherichia coli which alters its normal “run tumble” bias. E. coli bacteria taken from a swarm exhibit more highly extended runs (low tumble bias) and higher speeds than E. coli bacteria swimming individually in a liquid medium. The stability of the signaling protein CheZ is higher in swarmers, consistent with the observed elevation of CheZ levels and with the low tumble bias. We show that the tumble bias displayed by wild-type swarmers is the optimal bias for maximizing swarm expansion. In assays performed in liquid, swarm cells have reduced chemotactic performance. This behavior is specific to swarming, is not specific to growth on surfaces, and persists for a generation. Therefore, the chemotaxis signaling pathway is reprogrammed for swarming.
Collapse
|
34
|
Champion PA, Shrout JD. The 24th Annual Midwest Microbial Pathogenesis Meeting. J Bacteriol 2018; 200:e000950-18. [PMID: 29483166 PMCID: PMC5952387 DOI: 10.1128/jb.00095-18] [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] [Indexed: 11/20/2022] Open
Abstract
The 24th Annual Midwest Microbial Pathogenesis Conference (MMPC) was held at the University of Notre Dame from August 25-27, 2017. The conference provided an opportunity for scientists from the Midwest to discuss new advances in microbial pathogenesis, including how pathogens promote disease, and how they interact with each other, the microbiome and the host. This commentary highlights the MMPC history, the topics presented at the conference and the reports in this issue.
Collapse
Affiliation(s)
- Patricia A. Champion
- Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, USA
- Eck Institute for Global Health, University of Notre Dame, Notre Dame, Indiana, USA
| | - Joshua D. Shrout
- Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, USA
- Eck Institute for Global Health, University of Notre Dame, Notre Dame, Indiana, USA
- Department of Civil and Environmental Engineering and Earth Sciences, University of Notre Dame, Notre Dame, Indiana, USA
| |
Collapse
|