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Chan CW, Yang Z, Gan Z, Zhang R. Interplay of chemotactic force, Péclet number, and dimensionality dictates the dynamics of auto-chemotactic chiral active droplets. J Chem Phys 2024; 161:014904. [PMID: 38953449 DOI: 10.1063/5.0207355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2024] [Accepted: 05/31/2024] [Indexed: 07/04/2024] Open
Abstract
In living and synthetic active matter systems, the constituents can self-propel and interact with each other and with the environment through various physicochemical mechanisms. Among these mechanisms, chemotactic and auto-chemotactic effects are widely observed. The impact of (auto-)chemotactic effects on achiral active matter has been a recent research focus. However, the influence of these effects on chiral active matter remains elusive. Here, we develop a Brownian dynamics model coupled with a diffusion equation to examine the dynamics of auto-chemotactic chiral active droplets in both quasi-two-dimensional (2D) and three-dimensional (3D) systems. By quantifying the droplet trajectory as a function of the dimensionless Péclet number and chemotactic strength, our simulations well reproduce the curling and helical trajectories of nematic droplets in a surfactant-rich solution reported by Krüger et al. [Phys. Rev. Lett. 117, 048003 (2016)]. The modeled curling trajectory in 2D exhibits an emergent chirality, also consistent with the experiment. We further show that the geometry of the chiral droplet trajectories, characterized by the pitch and diameter, can be used to infer the velocities of the droplet. Interestingly, we find that, unlike the achiral case, the velocities of chiral active droplets show dimensionality dependence: its mean instantaneous velocity is higher in 3D than in 2D, whereas its mean migration velocity is lower in 3D than in 2D. Taken together, our particle-based simulations provide new insights into the dynamics of auto-chemotactic chiral active droplets, reveal the effects of dimensionality, and pave the way toward their applications, such as drug delivery, sensors, and micro-reactors.
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Affiliation(s)
- Chung Wing Chan
- Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR
- Thrust of Advanced Materials, and Guangzhou Municipal Key Laboratory of Materials Informatics, The Hong Kong University of Science and Technology (Guangzhou), Guangdong, China
| | - Zheng Yang
- Thrust of Advanced Materials, and Guangzhou Municipal Key Laboratory of Materials Informatics, The Hong Kong University of Science and Technology (Guangzhou), Guangdong, China
- Interdisciplinary Programs Office, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR
| | - Zecheng Gan
- Thrust of Advanced Materials, and Guangzhou Municipal Key Laboratory of Materials Informatics, The Hong Kong University of Science and Technology (Guangzhou), Guangdong, China
- Department of Mathematics, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR
| | - Rui Zhang
- Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR
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2
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Wen X, Feng J, Sang Y, Ge F, Chaté H, He Y. United under stress: High-speed transport network emerging at bacterial living edge. FUNDAMENTAL RESEARCH 2024; 4:563-569. [PMID: 38933215 PMCID: PMC11197528 DOI: 10.1016/j.fmre.2022.05.003] [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: 03/09/2022] [Revised: 04/14/2022] [Accepted: 05/01/2022] [Indexed: 11/19/2022] Open
Abstract
Individuals tend to move freely when there is enough room but would act collectively for their survival under external stress. In the case of living cells, for instance, when a drop of low-density flagellated bacterial solution is transferred onto the agar surface, the initially disordered movement of individual bacteria would be replaced with coordinated cell swarming after a lag phase of a few hours. Here, we study how such cooperation is established while overcoming the disorder at the onset of the lag phase with single nanoparticle tracking. Upon the spreading of the droplet, the bacteria in the solution cluster and align near the almost immobilized contact line confining the drop, forming a narrow ring of cells. As individual cells move in and out of the ring continuously, certain flow patterns emerge in the inter-bacterial fluid. We reveal high-speed long-distance unidirectional flows with definite chirality along the outside of the ring, along the inside of the ring and across the ring. We speculate that these flows enable the fast and efficient transport, facilitating the communication and unification of the bacterial community.
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Affiliation(s)
- Xiaodong Wen
- Department of Chemistry, Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology, Tshinghua University, Beijing 100084, China
| | - Jingjing Feng
- Department of Chemistry, Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology, Tshinghua University, Beijing 100084, China
| | - Yuqian Sang
- Department of Chemistry, Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology, Tshinghua University, Beijing 100084, China
| | - Feng Ge
- Department of Chemistry, Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology, Tshinghua University, Beijing 100084, China
| | - Hugues Chaté
- Service de Physique de l'Etat Condensé, CEA, CNRS, Université Paris-Saclay, CEA-Saclay, Gif-sur-Yvette 91191, France
- Beijing Computational Science Research Center, Beijing 100094, China
| | - Yan He
- Department of Chemistry, Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology, Tshinghua University, Beijing 100084, China
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3
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Chan CW, Wu D, Qiao K, Fong KL, Yang Z, Han Y, Zhang R. Chiral active particles are sensitive reporters to environmental geometry. Nat Commun 2024; 15:1406. [PMID: 38365770 PMCID: PMC10873462 DOI: 10.1038/s41467-024-45531-5] [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: 07/24/2023] [Accepted: 01/24/2024] [Indexed: 02/18/2024] Open
Abstract
Chiral active particles (CAPs) are self-propelling particles that break time-reversal symmetry by orbiting or spinning, leading to intriguing behaviors. Here, we examined the dynamics of CAPs moving in 2D lattices of disk obstacles through active Brownian dynamics simulations and granular experiments with grass seeds. We find that the effective diffusivity of the CAPs is sensitive to the structure of the obstacle lattice, a feature absent in achiral active particles. We further studied the transport of CAPs in obstacle arrays under an external field and found a reentrant directional locking effect, which can be used to sort CAPs with different activities. Finally, we demonstrated that parallelogram lattices of obstacles without mirror symmetry can separate clockwise and counter-clockwise CAPs. The mechanisms of the above three novel phenomena are qualitatively explained. As such, our work provides a basis for designing chirality-based tools for single-cell diagnosis and separation, and active particle-based environmental sensors.
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Affiliation(s)
- Chung Wing Chan
- Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR
| | - Daihui Wu
- Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR
| | - Kaiyao Qiao
- Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR
| | - Kin Long Fong
- Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR
- Physik-Department, Technische Universität München, James-Franck-Straße 1, 85748, Garching, Germany
| | - Zhiyu Yang
- Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR
| | - Yilong Han
- Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR
| | - Rui Zhang
- Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR.
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4
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Xu H, Nejad MR, Yeomans JM, Wu Y. Geometrical control of interface patterning underlies active matter invasion. Proc Natl Acad Sci U S A 2023; 120:e2219708120. [PMID: 37459530 PMCID: PMC10372614 DOI: 10.1073/pnas.2219708120] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Accepted: 06/16/2023] [Indexed: 07/20/2023] Open
Abstract
Interaction between active materials and the boundaries of geometrical confinement is key to many emergent phenomena in active systems. For living active matter consisting of animal cells or motile bacteria, the confinement boundary is often a deformable interface, and it has been unclear how activity-induced interface dynamics might lead to morphogenesis and pattern formation. Here, we studied the evolution of bacterial active matter confined by a deformable boundary. We found that an ordered morphological pattern emerged at the interface characterized by periodically spaced interfacial protrusions; behind the interfacial protrusions, bacterial swimmers self-organized into multicellular clusters displaying +1/2 nematic defects. Subsequently, a hierarchical sequence of transitions from interfacial protrusions to creeping branches allowed the bacterial active drop to rapidly invade surrounding space with a striking self-similar branch pattern. We found that this interface patterning is geometrically controlled by the local curvature of the interface, a phenomenon we denote as collective curvature sensing. Using a continuum active model, we revealed that the collective curvature sensing arises from enhanced active stresses near high-curvature regions, with the active length scale setting the characteristic distance between the interfacial protrusions. Our findings reveal a protrusion-to-branch transition as a unique mode of active matter invasion and suggest a strategy to engineer pattern formation of active materials.
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Affiliation(s)
- Haoran Xu
- Department of Physics, The Chinese University of Hong Kong, Shatin, NT, Hong Kong, People’s Republic of China
- Shenzhen Research Institute, The Chinese University of Hong Kong, Shatin, NT, Hong Kong, People’s Republic of China
| | - Mehrana R. Nejad
- Department of Physics, The Rudolf Peierls Centre for Theoretical Physics, University of Oxford, OxfordOX1 3PU, United Kingdom
| | - Julia M. Yeomans
- Department of Physics, The Rudolf Peierls Centre for Theoretical Physics, University of Oxford, OxfordOX1 3PU, United Kingdom
| | - Yilin Wu
- Department of Physics, The Chinese University of Hong Kong, Shatin, NT, Hong Kong, People’s Republic of China
- Shenzhen Research Institute, The Chinese University of Hong Kong, Shatin, NT, Hong Kong, People’s Republic of China
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5
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Ben Zion MY, Fersula J, Bredeche N, Dauchot O. Morphological computation and decentralized learning in a swarm of sterically interacting robots. Sci Robot 2023; 8:eabo6140. [PMID: 36812334 DOI: 10.1126/scirobotics.abo6140] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
Whereas naturally occurring swarms thrive when crowded, physical interactions in robotic swarms are either avoided or carefully controlled, thus limiting their operational density. Here, we present a mechanical design rule that allows robots to act in a collision-dominated environment. We introduce Morphobots, a robotic swarm platform developed to implement embodied computation through a morpho-functional design. By engineering a three-dimensional printed exoskeleton, we encode a reorientation response to an external body force (such as gravity) or a surface force (such as a collision). We show that the force orientation response is generic and can augment existing swarm robotic platforms (e.g., Kilobots) as well as custom robots even 10 times larger. At the individual level, the exoskeleton improves motility and stability and also allows encoding of two contrasting dynamical behaviors in response to an external force or a collision (including collision with a wall or a movable obstacle and on a dynamically tilting plane). This force orientation response adds a mechanical layer to the robot's sense-act cycle at the swarm level, leveraging steric interactions for collective phototaxis when crowded. Enabling collisions also promotes information flow, facilitating online distributed learning. Each robot runs an embedded algorithm that ultimately optimizes collective performance. We identify an effective parameter that controls the force orientation response and explore its implications in swarms that transition from dilute to crowded. Experimenting with physical swarms (of up to 64 robots) and simulated swarms (of up to 8192 agents) shows that the effect of morphological computation increases with growing swarm size.
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Affiliation(s)
- Matan Yah Ben Zion
- Gulliver UMR CNRS 7083, ESPCI, PSL Research University, 75005 Paris, France.,Institut des Systèmes Intelligents et de Robotique, Sorbonne Université, CNRS, ISIR, F-75005 Paris, France.,School of Physics and Astronomy and Center for Physics and Chemistry of Living Systems, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Jeremy Fersula
- Gulliver UMR CNRS 7083, ESPCI, PSL Research University, 75005 Paris, France.,Institut des Systèmes Intelligents et de Robotique, Sorbonne Université, CNRS, ISIR, F-75005 Paris, France
| | - Nicolas Bredeche
- Institut des Systèmes Intelligents et de Robotique, Sorbonne Université, CNRS, ISIR, F-75005 Paris, France
| | - Olivier Dauchot
- Gulliver UMR CNRS 7083, ESPCI, PSL Research University, 75005 Paris, France
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6
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Xu G, Huang T, Han Y, Chen Y. Morphologies and dynamics of free surfaces of crystals composed of active particles. SOFT MATTER 2022; 18:8830-8839. [PMID: 36367378 DOI: 10.1039/d2sm00783e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Active matter exhibits various collective motions and nonequilibrium phases, such as crystals; however, their surface properties have been poorly explored. Here, we use Brownian dynamics simulations to investigate the surface morphology and dynamics of two-dimensional active crystals during and after growth. For crystal growth on a substrate, the position and roughness of the crystal surface reach steady states at different times. In the steady state, the surface exhibits superdiffusive behaviour at the short time, and the roughness is insensitive to the roughening process and particle activity. We observe two-stage and three-stage surface roughening at different Péclet numbers. The result of dynamic scaling analysis shows that the surface is similar to anomalous roughening, which is distinct from the normal roughening typically found in conventional passive systems. Capillary wave theory for a thermal equilibrium system can describe the active surface fluctuations only in the long-wavelength regime, indicating that active particles mainly drive the surface out of equilibrium locally. These similarities and differences between the active and passive crystal surfaces are essential for understanding active crystals and interfaces.
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Affiliation(s)
- Guoqing Xu
- Center of Soft Matter Physics and Its Applications, Beihang University, Beijing 100191, China.
- School of Physics, Beihang University, Beijing 100191, China
| | - Tao Huang
- Faculty of Science, Kunming University of Science and Technology, Kunming 650093, Yunnan, China
| | - Yilong Han
- Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China.
| | - Yong Chen
- Center of Soft Matter Physics and Its Applications, Beihang University, Beijing 100191, China.
- School of Physics, Beihang University, Beijing 100191, China
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7
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Vigué A, Vautier D, Kaytoue A, Senger B, Arntz Y, Ball V, Ben Mlouka A, Gribova V, Hajjar-Garreau S, Hardouin J, Jouenne T, Lavalle P, Ploux L. Escherichia coli Biofilm Formation, Motion and Protein Patterns on Hyaluronic Acid and Polydimethylsiloxane Depend on Surface Stiffness. J Funct Biomater 2022; 13:jfb13040237. [PMID: 36412878 PMCID: PMC9680287 DOI: 10.3390/jfb13040237] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Revised: 11/05/2022] [Accepted: 11/08/2022] [Indexed: 11/16/2022] Open
Abstract
The surface stiffness of the microenvironment is a mechanical signal regulating biofilm growth without the risks associated with the use of bioactive agents. However, the mechanisms determining the expansion or prevention of biofilm growth on soft and stiff substrates are largely unknown. To answer this question, we used PDMS (polydimethylsiloxane, 9-574 kPa) and HA (hyaluronic acid gels, 44 Pa-2 kPa) differing in their hydration. We showed that the softest HA inhibited Escherichia coli biofilm growth, while the stiffest PDMS activated it. The bacterial mechanical environment significantly regulated the MscS mechanosensitive channel in higher abundance on the least colonized HA-44Pa, while Type-1 pili (FimA) showed regulation in higher abundance on the most colonized PDMS-9kPa. Type-1 pili regulated the free motion (the capacity of bacteria to move far from their initial position) necessary for biofilm growth independent of the substrate surface stiffness. In contrast, the total length travelled by the bacteria (diffusion coefficient) varied positively with the surface stiffness but not with the biofilm growth. The softest, hydrated HA, the least colonized surface, revealed the least diffusive and the least free-moving bacteria. Finally, this shows that customizing the surface elasticity and hydration, together, is an efficient means of affecting the bacteria's mobility and attachment to the surface and thus designing biomedical surfaces to prevent biofilm growth.
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Affiliation(s)
- Annabelle Vigué
- INSERM UMR-S 1121 Biomaterial Bioengineering, Centre de Recherche en Biomédecine de Strasbourg, 67084 Strasbourg, France
- Faculty of Dentistry, University of Strasbourg, 67000 Strasbourg, France
| | - Dominique Vautier
- INSERM UMR-S 1121 Biomaterial Bioengineering, Centre de Recherche en Biomédecine de Strasbourg, 67084 Strasbourg, France
- Faculty of Dentistry, University of Strasbourg, 67000 Strasbourg, France
| | - Amad Kaytoue
- INSERM UMR-S 1121 Biomaterial Bioengineering, Centre de Recherche en Biomédecine de Strasbourg, 67084 Strasbourg, France
- Faculty of Dentistry, University of Strasbourg, 67000 Strasbourg, France
| | - Bernard Senger
- INSERM UMR-S 1121 Biomaterial Bioengineering, Centre de Recherche en Biomédecine de Strasbourg, 67084 Strasbourg, France
- Faculty of Dentistry, University of Strasbourg, 67000 Strasbourg, France
| | - Youri Arntz
- INSERM UMR-S 1121 Biomaterial Bioengineering, Centre de Recherche en Biomédecine de Strasbourg, 67084 Strasbourg, France
- Faculty of Dentistry, University of Strasbourg, 67000 Strasbourg, France
| | - Vincent Ball
- INSERM UMR-S 1121 Biomaterial Bioengineering, Centre de Recherche en Biomédecine de Strasbourg, 67084 Strasbourg, France
- Faculty of Dentistry, University of Strasbourg, 67000 Strasbourg, France
| | - Amine Ben Mlouka
- PISSARO Proteomic Facility, IRIB, 76130 Mont-Saint-Aignan, France
| | - Varvara Gribova
- INSERM UMR-S 1121 Biomaterial Bioengineering, Centre de Recherche en Biomédecine de Strasbourg, 67084 Strasbourg, France
- Faculty of Dentistry, University of Strasbourg, 67000 Strasbourg, France
| | - Samar Hajjar-Garreau
- Mulhouse Materials Science Institute, CNRS/Haute Alsace University, 68057 Mulhouse, France
| | - Julie Hardouin
- PISSARO Proteomic Facility, IRIB, 76130 Mont-Saint-Aignan, France
- Polymers, Biopolymers, Surfaces Laboratory, CNRS/UNIROUEN/INSA Rouen, Normandie University, 76821 Rouen, France
| | - Thierry Jouenne
- PISSARO Proteomic Facility, IRIB, 76130 Mont-Saint-Aignan, France
- Polymers, Biopolymers, Surfaces Laboratory, CNRS/UNIROUEN/INSA Rouen, Normandie University, 76821 Rouen, France
| | - Philippe Lavalle
- INSERM UMR-S 1121 Biomaterial Bioengineering, Centre de Recherche en Biomédecine de Strasbourg, 67084 Strasbourg, France
- Faculty of Dentistry, University of Strasbourg, 67000 Strasbourg, France
| | - Lydie Ploux
- INSERM UMR-S 1121 Biomaterial Bioengineering, Centre de Recherche en Biomédecine de Strasbourg, 67084 Strasbourg, France
- Faculty of Dentistry, University of Strasbourg, 67000 Strasbourg, France
- CNRS, 67037 Strasbourg, France
- Correspondence:
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8
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Type IV Pilus Shapes a 'Bubble-Burst' Pattern Opposing Spatial Intermixing of Two Interacting Bacterial Populations. Microbiol Spectr 2022; 10:e0194421. [PMID: 35171019 PMCID: PMC8849093 DOI: 10.1128/spectrum.01944-21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Microbes are social organisms that commonly live in sessile biofilms. Spatial patterns of populations within biofilms can be important determinants of community-level properties. Spatial intermixing emerging from microbial interaction is one of the best-studied characteristics of spatial patterns. The specific levels of spatial intermixing critically contribute to how the dynamics and functioning of such communities are governed. However, the precise factors that determine spatial patterns and intermixing remain unclear. Here, we investigated the spatial patterning and intermixing of an engineered synthetic consortium composed of two mutualistic Pseudomonas stutzeri strains that degrade salicylate via metabolic cross-feeding. We found that the consortium self-organizes across space to form a previously unreported spatial pattern (here referred to as a ‘bubble-burst’ pattern) that exhibits a low level of intermixing. Interestingly, when the genes encoding type IV pili were deleted from both strains, a highly intermixed spatial pattern developed and increased the productivity of the entire community. The intermixed pattern was maintained in a robust manner across a wide range of initial ratios between the two strains. Our findings show that the type IV pilus plays a role in mitigating spatial intermixing of different populations in surface-attached microbial communities, with consequences for governing community-level properties. These insights provide tangible clues for the engineering of synthetic microbial systems that perform highly in spatially structured environments. IMPORTANCE When growing on surfaces, multispecies microbial communities form biofilms that exhibit intriguing spatial patterns. These patterns can significantly affect the overall properties of the community, enabling otherwise impermissible metabolic functions to occur as well as driving the evolutionary and ecological processes acting on communities. The development of these patterns is affected by several drivers, including cell-cell interactions, nutrient levels, density of founding cells, and surface properties. The type IV pilus is commonly found to mediate surface-associated behaviors of microorganisms, but its role on pattern formation within microbial communities is unclear. Here, we report that in a cross-feeding consortium, the type IV pilus affects the spatial intermixing of interacting populations involved in pattern formation and ultimately influences overall community productivity and robustness. This novel insight assists our understanding of the ecological processes of surface-attached microbial communities and suggests a potential strategy for engineering high-performance synthetic microbial communities.
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Ben Zion MY, Caba Y, Modin A, Chaikin PM. Cooperation in a fluid swarm of fuel-free micro-swimmers. Nat Commun 2022; 13:184. [PMID: 35013335 PMCID: PMC8748659 DOI: 10.1038/s41467-021-27870-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Accepted: 12/15/2021] [Indexed: 12/02/2022] Open
Abstract
While motile bacteria display rich dynamics in dense colonies, the phoretic nature of artificial micro-swimmers restricts their activity when crowded. Here we introduce a new class of synthetic micro-swimmers that are driven solely by light. By coupling a light absorbing particle to a fluid droplet we produce a colloidal chimera that transforms optical power into propulsive thermo-capillary action. The swimmers' internal drive allows them to operate for a long duration (days) and remain active when crowded, forming a high density fluid phase. We find that above a critical concentration, swimmers form a long lived crowded state that displays internal dynamics. When passive particles are introduced, the dense swimmer phase can re-arrange to spontaneously corral the passive particles. We derive a geometrical, depletion-like condition for corralling by identifying the role the passive particles play in controlling the effective concentration of the micro-swimmers.
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Affiliation(s)
- Matan Yah Ben Zion
- Center for Soft Matter Research, Department of Physics, New York University, 726 Broadway Avenue, New York, NY, 10003, USA.
- UMR Gulliver 7083 CNRS, ESPCI Paris, PSL Research University, 10 rue Vauquelin, 75005, Paris, France.
| | - Yaelin Caba
- Center for Soft Matter Research, Department of Physics, New York University, 726 Broadway Avenue, New York, NY, 10003, USA
| | - Alvin Modin
- Center for Soft Matter Research, Department of Physics, New York University, 726 Broadway Avenue, New York, NY, 10003, USA
| | - Paul M Chaikin
- Center for Soft Matter Research, Department of Physics, New York University, 726 Broadway Avenue, New York, NY, 10003, USA
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10
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Huang D, Du Y, Jiang H, Hou Z. Emergent spiral vortex of confined biased active particles. Phys Rev E 2021; 104:034606. [PMID: 34654190 DOI: 10.1103/physreve.104.034606] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Accepted: 06/15/2021] [Indexed: 11/07/2022]
Abstract
Confinement is known to have profound effects on the collective dynamics of many active systems. Here, we investigate a modeled active system in circular confinement consisting of biased active particles, where the direction of active force deviates a biased angle from the principle orientation of the anisotropic interaction. We find that such particles can spontaneously form a spiral vortex with two concentric and counter-rotating regions near the boundary. The emerged vortex can be measured by the vortex order parameter which shows nonmonotonic dependencies on both the biased angle and the strength of the anisotropic interaction. Our work can provide an understanding of such dynamic behaviors and enable different strategies for designing ordered collective behaviors.
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Affiliation(s)
- Deping Huang
- Department of Chemical Physics and Hefei National Laboratory for Physical Sciences at Microscales, iChEM, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Yunfei Du
- Department of Chemical Physics and Hefei National Laboratory for Physical Sciences at Microscales, iChEM, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Huijun Jiang
- Department of Chemical Physics and Hefei National Laboratory for Physical Sciences at Microscales, iChEM, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Zhonghuai Hou
- Department of Chemical Physics and Hefei National Laboratory for Physical Sciences at Microscales, iChEM, University of Science and Technology of China, Hefei, Anhui 230026, China
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11
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Gao Y, Zhang W, Li Y. Microbial community coalescence: does it matter in the Three Gorges Reservoir? WATER RESEARCH 2021; 205:117638. [PMID: 34560619 DOI: 10.1016/j.watres.2021.117638] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Revised: 08/14/2021] [Accepted: 09/02/2021] [Indexed: 06/13/2023]
Abstract
The microbial community coalescence describes the mixing of microbial communities and the merging of their surrounding environments. Despite its prevalence in natural ecosystems and its potential influence on ecological processes, little research focused on the extent of coalescence between aquatic microbial communities. In this research, we analyzed the microbial communities in the Three Gorges Reservoir, a typical deep-water reservoir on the Yangtze River. The biogeography and the coalescence of microbial communities in water and sediment were illustrated and analyzed based on 16S rRNA gene amplicon sequence variants (ASVs). Differences in composition and diversity were identified between microbial communities in water and sediment, and microbial communities in sediment were more diverse than those in water. Between adjacent communities, by calculating the proportion of overlapped taxa, adopting the SourceTracker algorithm, and quantifying the connectivity of microbial cohesion, we found that the extent of intra-medium coalescence was strong (19.8%) and inter-media coalescence was faint (0.2%). 50 keystone species were selected using the cohesion metric. They displayed a stronger coalescence extent than average, and formed an accumulating pattern from upstream to downstream in the Three Gorges Reservoir, exhibiting their importance in the ecological network. Potential influencing factors of microbial community coalescence in aquatic environments were discussed, including environmental conditions, types of habitats, suspended particles in water, and microscale microbial activities. To summarize, this research depicted the coalescence of microbial communities in a deep-water reservoir and emphasized its ecological importance. We anticipate more attention and further research on the processes of microbial coalescence in the aquatic environment, which might provide new insights into turnover of microbial keystone species and changes in aquatic ecological conditions.
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Affiliation(s)
- Yu Gao
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, PR China.
| | - Wenlong Zhang
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, PR China.
| | - Yi Li
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, PR China.
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12
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Edge current and pairing order transition in chiral bacterial vortices. Proc Natl Acad Sci U S A 2021; 118:2107461118. [PMID: 34561308 DOI: 10.1073/pnas.2107461118] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/24/2021] [Indexed: 12/21/2022] Open
Abstract
Bacterial suspensions show turbulence-like spatiotemporal dynamics and vortices moving irregularly inside the suspensions. Understanding these ordered vortices is an ongoing challenge in active matter physics, and their application to the control of autonomous material transport will provide significant development in microfluidics. Despite the extensive studies, one of the key aspects of bacterial propulsion has remained elusive: The motion of bacteria is chiral, i.e., it breaks mirror symmetry. Therefore, the mechanism of control of macroscopic active turbulence by microscopic chirality is still poorly understood. Here, we report the selective stabilization of chiral rotational direction of bacterial vortices in achiral circular microwells sealed by an oil/water interface. The intrinsic chirality of bacterial swimming near the top and bottom interfaces generates chiral collective motions of bacteria at the lateral boundary of the microwell that are opposite in directions. These edge currents grow stronger as bacterial density increases, and, within different top and bottom interfaces, their competition leads to a global rotation of the bacterial suspension in a favored direction, breaking the mirror symmetry of the system. We further demonstrate that chiral edge current favors corotational configurations of interacting vortices, enhancing their ordering. The intrinsic chirality of bacteria is a key feature of the pairing order transition from active turbulence, and the geometric rule of pairing order transition may shed light on the strategy for designing chiral active matter.
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An effective and efficient model of the near-field hydrodynamic interactions for active suspensions of bacteria. Proc Natl Acad Sci U S A 2021; 118:2100145118. [PMID: 34260387 PMCID: PMC8285906 DOI: 10.1073/pnas.2100145118] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Active suspensions of microswimmers demonstrate novel emergent behaviors (self-organizations, active turbulence, etc.) on macroscopic length scales. For such systems with, minimally, thousands of microswimmers, direct numerical simulations of the hydrodynamic interactions are computationally infeasible, and reduced models are needed. We demonstrated that existing models are not satisfactory in describing the hydrodynamic interactions for microswimmers in close proximity with even qualitatively erroneous predictions, indicating a pressing need for an adequate model. We propose a model that is both physically effective and computationally efficient in describing such hydrodynamics. The main novelty of our model is the description of hydrodynamic interactions through a resistance tensor, as opposed to an effective steric interaction in existing models. Near-field hydrodynamic interactions in active fluids are essential to determine many important emergent behaviors observed, but have not been successfully modeled so far. In this work, we propose an effective model capturing the essence of the near-field hydrodynamic interactions through a tensorial coefficient of resistance, validated numerically by a pedagogic model system consisting of an Escherichia coli bacterium and a passive sphere. In a critical test case that studies the scattering angle of the bacterium–sphere pair dynamics, we prove that the near-field hydrodynamics can make a qualitative difference even for this simple two-body system: Calculations based on the proposed model reveal a region in parameter space where the bacterium is trapped by the passive sphere, a phenomenon that is regularly observed in experiments but cannot be explained by any existing model. In the end, we demonstrate that our model also leads to efficient simulation of active fluids with tens of thousands of bacteria, sufficiently large for investigations of many emergent behaviors.
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Wong GCL, Antani JD, Lele PP, Chen J, Nan B, Kühn MJ, Persat A, Bru JL, Høyland-Kroghsbo NM, Siryaporn A, Conrad JC, Carrara F, Yawata Y, Stocker R, Brun YV, Whitfield GB, Lee CK, de Anda J, Schmidt WC, Golestanian R, O’Toole GA, Floyd KA, Yildiz FH, Yang S, Jin F, Toyofuku M, Eberl L, Nomura N, Zacharoff LA, El-Naggar MY, Yalcin SE, Malvankar NS, Rojas-Andrade MD, Hochbaum AI, Yan J, Stone HA, Wingreen NS, Bassler BL, Wu Y, Xu H, Drescher K, Dunkel J. Roadmap on emerging concepts in the physical biology of bacterial biofilms: from surface sensing to community formation. Phys Biol 2021; 18:10.1088/1478-3975/abdc0e. [PMID: 33462162 PMCID: PMC8506656 DOI: 10.1088/1478-3975/abdc0e] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Accepted: 01/14/2021] [Indexed: 11/29/2022]
Abstract
Bacterial biofilms are communities of bacteria that exist as aggregates that can adhere to surfaces or be free-standing. This complex, social mode of cellular organization is fundamental to the physiology of microbes and often exhibits surprising behavior. Bacterial biofilms are more than the sum of their parts: single-cell behavior has a complex relation to collective community behavior, in a manner perhaps cognate to the complex relation between atomic physics and condensed matter physics. Biofilm microbiology is a relatively young field by biology standards, but it has already attracted intense attention from physicists. Sometimes, this attention takes the form of seeing biofilms as inspiration for new physics. In this roadmap, we highlight the work of those who have taken the opposite strategy: we highlight the work of physicists and physical scientists who use physics to engage fundamental concepts in bacterial biofilm microbiology, including adhesion, sensing, motility, signaling, memory, energy flow, community formation and cooperativity. These contributions are juxtaposed with microbiologists who have made recent important discoveries on bacterial biofilms using state-of-the-art physical methods. The contributions to this roadmap exemplify how well physics and biology can be combined to achieve a new synthesis, rather than just a division of labor.
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Affiliation(s)
- Gerard C L Wong
- Department of Bioengineering, University of California—Los Angeles, Los Angeles, California, CA 90095, United States of America
- Department of Chemistry and Biochemistry, University of California—Los Angeles, Los Angeles, California, CA 90095, United States of America
- California NanoSystems Institute, University of California—Los Angeles, Los Angeles, California, CA 90095, United States of America
| | - Jyot D Antani
- Artie McFerrin Department of Chemical Engineering, Texas A & M University, College Station, TX 77843, United States of America
| | - Pushkar P Lele
- Artie McFerrin Department of Chemical Engineering, Texas A & M University, College Station, TX 77843, United States of America
| | - Jing Chen
- Department of Biological Sciences, Virginia Polytechnic Institute and State University, Blacksburg, VA24061, United States of America
| | - Beiyan Nan
- Department of Biology, Texas A & M University, College Station, Texas, TX 77845, United States of America
| | - Marco J Kühn
- Institute of Bioengineering and Global Health Institute, School of Life Sciences, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Alexandre Persat
- Institute of Bioengineering and Global Health Institute, School of Life Sciences, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Jean-Louis Bru
- Department of Molecular Biology & Biochemistry, University of California—Irvine, California, CA 92697, United States of America
| | | | - Albert Siryaporn
- Department of Molecular Biology & Biochemistry, University of California—Irvine, California, CA 92697, United States of America
- Department of Physics & Astronomy, University of California—Irvine, California, CA 92697, United States of America
| | - Jacinta C Conrad
- William A Brookshire Department of Chemical and Biomolecular Engineering, University of Houston, Houston, Texas, TX 77204, United States of America
| | - Francesco Carrara
- Institute of Environmental Engineering, Department of Civil, Environmental and Geomatic Engineering, ETH Zurich, 8093 Zurich, Switzerland
| | - Yutaka Yawata
- Faculty of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8572, Japan
- Microbiology Research Center for Sustainability, University of Tsukuba, 305-8572 Tsukuba, Japan
| | - Roman Stocker
- Institute of Environmental Engineering, Department of Civil, Environmental and Geomatic Engineering, ETH Zurich, 8093 Zurich, Switzerland
| | - Yves V Brun
- University of Montreal, Faculty of Medicine, Montreal, Quebec, H3C 3J7, Canada
| | - Gregory B Whitfield
- University of Montreal, Faculty of Medicine, Montreal, Quebec, H3C 3J7, Canada
| | - Calvin K Lee
- Department of Bioengineering, University of California—Los Angeles, Los Angeles, California, CA 90095, United States of America
- Department of Chemistry and Biochemistry, University of California—Los Angeles, Los Angeles, California, CA 90095, United States of America
- California NanoSystems Institute, University of California—Los Angeles, Los Angeles, California, CA 90095, United States of America
| | - Jaime de Anda
- Department of Bioengineering, University of California—Los Angeles, Los Angeles, California, CA 90095, United States of America
- Department of Chemistry and Biochemistry, University of California—Los Angeles, Los Angeles, California, CA 90095, United States of America
- California NanoSystems Institute, University of California—Los Angeles, Los Angeles, California, CA 90095, United States of America
| | - William C Schmidt
- Department of Bioengineering, University of California—Los Angeles, Los Angeles, California, CA 90095, United States of America
- Department of Chemistry and Biochemistry, University of California—Los Angeles, Los Angeles, California, CA 90095, United States of America
- California NanoSystems Institute, University of California—Los Angeles, Los Angeles, California, CA 90095, United States of America
| | - Ramin Golestanian
- Max Planck Institute for Dynamics and Self-Organization (MPIDS), D-37077 Göttingen, Germany
- Rudolf Peierls Centre for Theoretical Physics, University of Oxford, Oxford OX1 3PU, United Kingdom
| | - George A O’Toole
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755, United States of America
| | - Kyle A Floyd
- Department of Microbiology and Environmental Toxicology, University of California—Santa Cruz, Santa Cruz, California, CA 95060, United States of America
| | - Fitnat H Yildiz
- Department of Microbiology and Environmental Toxicology, University of California—Santa Cruz, Santa Cruz, California, CA 95060, United States of America
| | - Shuai Yang
- CAS Key Laboratory of Quantitative Engineering Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, People’s Republic of China
| | - Fan Jin
- CAS Key Laboratory of Quantitative Engineering Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, People’s Republic of China
| | - Masanori Toyofuku
- Faculty of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8572, Japan
- Microbiology Research Center for Sustainability, University of Tsukuba, 305-8572 Tsukuba, Japan
| | - Leo Eberl
- Department of Plant and Microbial Biology, University of Zürich, 8008 Zürich, Switzerland
| | - Nobuhiko Nomura
- Faculty of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8572, Japan
- Microbiology Research Center for Sustainability, University of Tsukuba, 305-8572 Tsukuba, Japan
| | - Lori A Zacharoff
- Department of Physics and Astronomy, University of Southern California, Los Angeles, California, CA 90089, United States of America
- Department of Chemistry, University of Southern California, Los Angeles, California, CA 90089, United States of America
| | - Mohamed Y El-Naggar
- Department of Physics and Astronomy, University of Southern California, Los Angeles, California, CA 90089, United States of America
- Department of Chemistry, University of Southern California, Los Angeles, California, CA 90089, United States of America
- Department of Biological Sciences, University of Southern California, Los Angeles, California, CA 90089, United States of America
| | - Sibel Ebru Yalcin
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut, CT 06516, United States of America
- Microbial Sciences Institute, Yale University, New Haven, Connecticut, CT 06516, United States of America
| | - Nikhil S Malvankar
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut, CT 06516, United States of America
- Microbial Sciences Institute, Yale University, New Haven, Connecticut, CT 06516, United States of America
| | - Mauricio D Rojas-Andrade
- Department of Materials Science and Engineering, University of California—Irvine, Irvine, California CA 92697, United States of America
| | - Allon I Hochbaum
- Department of Molecular Biology & Biochemistry, University of California—Irvine, California, CA 92697, United States of America
- Department of Materials Science and Engineering, University of California—Irvine, Irvine, California CA 92697, United States of America
- Department of Chemistry, University of California—Irvine, Irvine, California, CA 92697, United States of America
- Department of Chemical and Biomolecular Engineering, University of California—Irvine, Irvine, California, CA 92697, United States of America
| | - Jing Yan
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, Connecticut, CT 06511, United States of America
| | - Howard A Stone
- Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, New Jersey, NJ 08544, United States of America
| | - Ned S Wingreen
- Department of Molecular Biology, Princeton University, Princeton, New Jersey, NJ 08544, United States of America
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey, NJ 08544, United States of America
| | - Bonnie L Bassler
- Department of Molecular Biology, Princeton University, Princeton, New Jersey, NJ 08544, United States of America
- The Howard Hughes Medical Institute, Chevy Chase, Maryland MD 20815, United States of America
| | - Yilin Wu
- Department of Physics and Shenzhen Research Institute, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, People’s Republic of China
| | - Haoran Xu
- Department of Physics and Shenzhen Research Institute, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, People’s Republic of China
| | - Knut Drescher
- Max Planck Institute for Terrestrial Microbiology, 35043 Marburg, Germany
- Department of Physics, Philipps-Universität Marburg, 35043 Marburg, Germany
| | - Jörn Dunkel
- Department of Mathematics, Massachusetts Institute of Technology, Cambridge, Massachusetts, MA 02139-4307, United States of America
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Guzmán-Lastra F, Löwen H, Mathijssen AJTM. Active carpets drive non-equilibrium diffusion and enhanced molecular fluxes. Nat Commun 2021; 12:1906. [PMID: 33771985 PMCID: PMC7997990 DOI: 10.1038/s41467-021-22029-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Accepted: 02/20/2021] [Indexed: 11/08/2022] Open
Abstract
Biological activity is often highly concentrated on surfaces, across the scales from molecular motors and ciliary arrays to sessile and motile organisms. These 'active carpets' locally inject energy into their surrounding fluid. Whereas Fick's laws of diffusion are established near equilibrium, it is unclear how to solve non-equilibrium transport driven by such boundary-actuated fluctuations. Here, we derive the enhanced diffusivity of molecules or passive particles as a function of distance from an active carpet. Following Schnitzer's telegraph model, we then cast these results into generalised Fick's laws. Two archetypal problems are solved using these laws: First, considering sedimentation towards an active carpet, we find a self-cleaning effect where surface-driven fluctuations can repel particles. Second, considering diffusion from a source to an active sink, say nutrient capture by suspension feeders, we find a large molecular flux compared to thermal diffusion. Hence, our results could elucidate certain non-equilibrium properties of active coating materials and life at interfaces.
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Affiliation(s)
- Francisca Guzmán-Lastra
- Escuela de Data Science, Facultad de Estudios Interdisciplinarios, Universidad Mayor, Santiago, Chile.
- Departamento de Física, FCFM Universidad de Chile, Santiago, Chile.
| | - Hartmut Löwen
- Institut für Theoretische Physik II: Weiche Materie, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
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Rooney LM, Amos WB, Hoskisson PA, McConnell G. Intra-colony channels in E. coli function as a nutrient uptake system. THE ISME JOURNAL 2020; 14:2461-2473. [PMID: 32555430 PMCID: PMC7490401 DOI: 10.1038/s41396-020-0700-9] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Revised: 05/05/2020] [Accepted: 05/12/2020] [Indexed: 12/13/2022]
Abstract
The ability of microorganisms to grow as aggregated assemblages has been known for many years, however their structure has remained largely unexplored across multiple spatial scales. The development of the Mesolens, an optical system which uniquely allows simultaneous imaging of individual bacteria over a 36 mm2 field of view, has enabled the study of mature Escherichia coli macro-colony biofilm architecture like never before. The Mesolens enabled the discovery of intra-colony channels on the order of 10 μm in diameter, that are integral to E. coli macro-colony biofilms and form as an emergent property of biofilm growth. These channels have a characteristic structure and re-form after total mechanical disaggregation of the colony. We demonstrate that the channels are able to transport particles and play a role in the acquisition of and distribution of nutrients through the biofilm. These channels potentially offer a new route for the delivery of dispersal agents for antimicrobial drugs to biofilms, ultimately lowering their impact on public health and industry.
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Affiliation(s)
- Liam M Rooney
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, 161 Cathedral Street, Glasgow, G4 0RE, UK.
- Institute of Biological Chemistry, Biophysics and Bioengineering, School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh, EH14 4AS, UK.
| | - William B Amos
- Department of Physics, SUPA, University of Strathclyde, 107 Rottenrow East, Glasgow, G4 0NG, UK
| | - Paul A Hoskisson
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, 161 Cathedral Street, Glasgow, G4 0RE, UK
| | - Gail McConnell
- Department of Physics, SUPA, University of Strathclyde, 107 Rottenrow East, Glasgow, G4 0NG, UK
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17
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Kichatov B, Korshunov A, Sudakov V, Kolobov A, Gubernov V, Golubkov A, Kiverin A. Kinetics of cluster formation in active suspension: Coarsening regime. J Chem Phys 2020; 153:084902. [DOI: 10.1063/5.0013665] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Affiliation(s)
- Boris Kichatov
- Lebedev Physical Institute, Russian Academy of Sciences, 119991 Moscow, Russia
| | - Alexey Korshunov
- Lebedev Physical Institute, Russian Academy of Sciences, 119991 Moscow, Russia
| | - Vladimir Sudakov
- Lebedev Physical Institute, Russian Academy of Sciences, 119991 Moscow, Russia
| | - Andrey Kolobov
- Lebedev Physical Institute, Russian Academy of Sciences, 119991 Moscow, Russia
| | - Vladimir Gubernov
- Lebedev Physical Institute, Russian Academy of Sciences, 119991 Moscow, Russia
| | - Alexandr Golubkov
- Lebedev Physical Institute, Russian Academy of Sciences, 119991 Moscow, Russia
| | - Alexey Kiverin
- Moscow State Technical University by N. E. Bauman, 105005 Moscow, Russia
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18
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Dynamic motility selection drives population segregation in a bacterial swarm. Proc Natl Acad Sci U S A 2020; 117:4693-4700. [PMID: 32060120 DOI: 10.1073/pnas.1917789117] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Population expansion in space, or range expansion, is widespread in nature and in clinical settings. Space competition among heterogeneous subpopulations during range expansion is essential to population ecology, and it may involve the interplay of multiple factors, primarily growth and motility of individuals. Structured microbial communities provide model systems to study space competition during range expansion. Here we use bacterial swarms to investigate how single-cell motility contributes to space competition among heterogeneous bacterial populations during range expansion. Our results revealed that motility heterogeneity can promote the spatial segregation of subpopulations via a dynamic motility selection process. The dynamic motility selection is enabled by speed-dependent persistence time bias of single-cell motion, which presumably arises from physical interaction between cells in a densely packed swarm. We further showed that the dynamic motility selection may contribute to collective drug tolerance of swarming colonies by segregating subpopulations with transient drug tolerance to the colony edge. Our results illustrate that motility heterogeneity, or "motility fitness," can play a greater role than growth rate fitness in determining the short-term spatial structure of expanding populations.
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