Questo studio è stato supportato dal Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD) e dal Teaching Reform Research Project della China Pharmaceutical University (2019XJYB18).

1. Preparazione del mezzo semisolido
<ol><li>Agar semisolido tradizionale
	<ol><li>Preparare l'agar semisolido tradizionale secondo la ricetta del mezzo di prova della motilità batterica utilizzando gli ingredienti di base11. Sciogliere 10 g di triptosio, 15 g di NaCl, 4 g di agar in acqua distillata a sufficienza, regolare il pH a 7,2 ± 0,2 e portare il volume finale a 1.000 ml.</li>
		<li>Autoclavare l'agar a 121 °C per 20 minuti ed erogarlo in provette da 10 mL come mezzo semisolido alto 3 cm.</li>
	</ol></li>
	<li>Agar semisolido tradizionale con TTC
	<ol><li>Dopo aver sterilizzato in autoclave il mezzo semisolido convenzionale, raffreddarlo a 50 °C, aggiungere 5 ml di soluzione sterile di TTC all'1% a 100 ml di terreno, mescolare ed erogarlo in provette da 10 ml per formare un mezzo semisolido alto 3 cm.</li>
	</ol></li>
</ol>2. Ceppi batterici
NOTA: Ottanta ceppi sono stati isolati dall'ambiente acquatico e identificati utilizzando uno strumento automatizzato di identificazione dei batteri (vedere la tabella dei materiali), tra cui Escherichia coli, Pseudomonas aeruginosa, Salmonella spp., Vibrio spp., Klebsiella pneumoniae e Aeromonas hydrophila (Tabella 1). Lo Staphylococcus aureus (vedi la tabella dei materiali) è stato usato come controllo non mobile negativo; Escherichia coli, Pseudomonas aeruginosa e Salmonella typhimurium (vedere la tabella dei materiali) sono stati utilizzati come ceppi di controllo positivo.
<ol><li>Identificare i ceppi batterici da utilizzare per l'analisi della motilità.</li>
	<li>Includere controlli non mobili negativi e ceppi di controllo positivi mobili.</li>
</ol>3. Osservazione della motilità batterica potenziata da TTC
<ol><li>Prelevare singole colonie di batteri in esame dalle piastre di agar e inocularle nei due mezzi semisolidi di cui sopra (fasi 1.1.2 e 1.2.1) mediante puntura con aghi inoculanti.</li>
	<li>Coltivare i tubi a 37 °C nell'incubatore per 24-48 ore per osservare i risultati.</li>
	<li>Osservare lo stato di crescita: caratterizzare i batteri come non mobili (-) se solo la linea di puntura è rossa. Caratterizzare i batteri come mobili (+) se il colore rosso si diffonde leggermente verso l'esterno lungo la linea di puntura12.</li>
</ol>4. Effetto di diverse concentrazioni di agar sulla motilità batterica
<ol><li>Preparare mezzi semisolidi contenenti 0,3%, 0,5% e 0,8% di agar e inocularli mediante foratura, come descritto sopra. Osservare i risultati dopo 24-48 ore di incubazione.</li>
</ol>

<ol>
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Gli autori non hanno conflitti di interesse da rivelare.

La rilevazione della motilità batterica con il metodo del mezzo semisolido è influenzata da molti fattori13,14. Le condizioni di crescita batterica, come l'ossigeno (aerobico sulla superficie dell'agar, non aerobico sul fondo del tubo con il mezzo semisolido), il pH e la temperatura, possono influenzare la vitalità dei flagelli batterici, che possono portare a una ridotta motilità o addirittura alla perdita di motilità15. Inoltre, alc...

La motilità batterica svolge un ruolo critico nella patogenicità batterica, nella formazione di biofilm e nella resistenza ai farmaci1. La motilità batterica è strettamente associata alla patogenicità ed è necessaria per la colonizzazione batterica durante l'infezione precoce delle cellule ospiti2. La formazione di biofilm è strettamente correlata alla motilità batterica, in cui i batteri aderiscono alla superficie dei mezzi solidi attraverso la motilità. La motilità batterica è stata a lungo considerata positivamente correlata con la formazione di biofilm. Un alto grado di resistenza batterica ai farmaci dovuto al biofilm può portare a infezioni persistenti che rappresentano una minaccia per la salute umana 3,4,5. Pertanto, è importante rilevare la motilità batterica. Il test di motilità batterica viene utilizzato principalmente per esaminare la motilità di diverse forme di batteri allo stato vivente, che possono determinare indirettamente la presenza o l'assenza di flagelli e, quindi, ha un ruolo importante nell'identificazione dei batteri.
Esistono metodi diretti e indiretti per rilevare la motilità batterica6. Poiché i batteri con flagelli mostrano motilità, è possibile rilevare se i batteri sono mobili indirettamente rilevando la presenza o l'assenza di flagelli. Ad esempio, è possibile rilevare la motilità indirettamente mediante microscopia elettronica e colorazione flagellare per indicare che i batteri sono mobili. È anche possibile rilevare con metodi diretti, come la caduta della sospensione e i metodi di puntura semisolida. 
Il metodo di puntura semisolida comunemente usato nei laboratori universitari di microbiologia per rilevare la motilità batterica inocula i batteri nella puntura nel mezzo di agar semisolido contenente 0,4-0,8% di agar, secondo la direzione della crescita batterica. Se i batteri crescono lungo la linea di puntura per diffondersi, appaiono tracce di crescita simili a nuvole (simili a pennelli), che indicano la presenza di flagelli e, quindi, di motilità. Se non ci sono tracce di crescita della linea di puntura, il batterio non è né flagellato né mobile. 
Tuttavia, questo metodo ha i suoi svantaggi: i batteri sono incolori e trasparenti, l'attività flagellare è influenzata dalle caratteristiche fisiologiche dei batteri viventi e da altri fattori, dalla concentrazione di agar e dal piccolo diametro della provetta. Inoltre, i batteri aerobici sono adatti solo per la crescita sulla superficie dell'agar, influenzando l'osservazione della motilità batterica. Quindi, per migliorare questo esperimento, il cloruro di 2,3,5-trifeniltetrazolio (TTC) (incolore) è stato aggiunto al mezzo per stabilire un metodo più affidabile e intuitivo per determinare la motilità batterica rispetto all'attuale metodo di puntura diretta che utilizza deidrogenasi intracellulari per catalizzare la formazione di un prodotto rosso di TTC 7,8,9,10.

<table><tbody><tr><td>Bacto Agar</td><td>Difco</td><td></td><td></td></tr><tr><td>&lt;em&gt;Escherichia coli&lt;/em&gt;</td><td>ATCC</td><td>ATCC25922</td><td>Positive control</td></tr><tr><td>&lt;em&gt;Pseudomonas aeruginosa&lt;/em&gt;</td><td>ATCC</td><td>ATCC27853</td><td>Positive control</td></tr><tr><td>&lt;em&gt;Salmonella typhimurium&lt;/em&gt;</td><td>ATCC</td><td>ATCC14028</td><td>Positive control</td></tr><tr><td>&lt;em&gt;Staphylococcus aureus&lt;/em&gt;</td><td>ATCC</td><td>ATCC25923</td><td>Negative nonmotile control</td></tr><tr><td>Tryptose</td><td>&amp;nbsp;OXOID</td><td></td><td></td></tr><tr><td>TTC</td><td>Sigma</td><td>298-96-4</td><td></td></tr><tr><td>VITEK 2 automated microbial identification system</td><td>Bio M&amp;eacute;rieux</td><td></td><td></td></tr></tbody></table>

visualizing bacterial motility based on a color reaction

La motilità batterica è cruciale per la patogenicità batterica, la formazione di biofilm e la resistenza ai farmaci. La motilità batterica è cruciale per l'invasione e/o la diffusione di molte specie patogene. Pertanto, è importante rilevare la motilità batterica. Le condizioni di crescita batterica, come ossigeno, pH e temperatura, possono influenzare la crescita batterica e l'espressione dei flagelli batterici. Ciò può portare a una ridotta motilità o addirittura alla perdita di motilità, con conseguente valutazione imprecisa della motilità batterica. Sulla base della reazione cromatica del cloruro di 2,3,5-trifeniltetrazolio (TTC) da parte delle deidrogenasi intracellulari di batteri viventi, il TTC è stato aggiunto all'agar semisolido tradizionale per il rilevamento della motilità batterica. I risultati hanno mostrato che questo metodo di agar semisolido TTC per la rilevazione della motilità batterica è semplice, facile da usare e non coinvolge strumenti grandi e costosi. I risultati hanno anche mostrato che la motilità più alta è stata osservata nel mezzo semisolido preparato con agar allo 0,3%. Rispetto al tradizionale mezzo semisolido, i risultati sono più facili da valutare e più accurati.

Sia i ceppi standard che i ceppi isolati sono stati confrontati per il rilevamento della motilità e i risultati sono mostrati nella Tabella 1. A causa dell'assenza di flagelli, Staphylococcus aureus e Klebsiella pneumoniae sono cresciuti solo lungo la linea inoculata su terreni semisolidi tradizionali e TTC. Al contrario, Pseudomonas aeruginosa, Escherichia coli e Salmonella typhimurium hanno mostrato una crescita in tutte le direzioni attorno alla linea inoc...

Watch this Scientific Journal Video about Visualizing Bacterial Motility Based on a Color Reaction at JoVE.com

Visualizing Bacterial Motility Based on a Color Reaction

Qui, presentiamo un protocollo per rilevare la motilità batterica basata su una reazione di colore. I principali vantaggi di questo metodo sono che è facile da valutare e più accurato e non richiede attrezzature specializzate.

Visualizzazione della motilità batterica basata su una reazione cromatica

Bacterial motility is crucial for bacterial pathogenicity, biofilm formation, and drug resistance. Bacterial motility is crucial for the invasion and/or ...

visualizing-bacterial-motility-based-on-a-color-reaction

Research

JoVE Journal

Biology

3.8K Views.  China Pharmaceutical University. Qui, presentiamo un protocollo per rilevare la motilità batterica basata su una reazione di colore. I principali vantaggi di questo metodo sono che è facile da valutare e più accurato e non richiede attrezzature specializzate.

Video: Visualizing Bacterial Motility Based on a Color Reaction

A Microfluidic Device for Quantifying Bacterial Chemotaxis in Stable Concentration Gradients

Chemotaxis allows bacteria to approach sources of attractant chemicals or to avoid sources of repellent chemicals. Bacteria constantly monitor the concentration of specific chemoeffectors by comparing the current concentration to the concentration detected a few seconds earlier. This comparison determines the net direction of movement. Although multiple, competing gradients often coexist in nature, conventional approaches for investigating bacterial chemotaxis are suboptimal for quantifying migration in response to concentration gradients of attractants and repellents. Here, we describe the development of a microfluidic chemotaxis model for presenting precise and stable concentration gradients of chemoeffectors to bacteria and quantitatively investigating their response to the applied gradient. The device is versatile in that concentration gradients of any desired absolute concentration and gradient strength can be easily generated by diffusive mixing. The device is demonstrated using the response of Escherichia coli RP437 to gradients of amino acids and nickel ions.

This protocol describes the development of a microfluidic device for investigating bacterial chemotaxis in stable concentration gradients of chemoeffectors.

Un dispositivo a microfluidi per quantificare chemiotassi batterica in gradienti di concentrazione stabile

Chemotaxis allows bacteria to approach sources of attractant chemicals or to avoid sources of repellent chemicals. Bacteria constantly monitor the ...

Ricerca

Biologia

Quantifying Bacterial Surface Swarming Motility on Inducer Gradient Plates

Bacterial swarming motility is a common microbiological phenotype that bacterial communities use to migrate over semisolid surfaces. In investigations of induced swarming motility, specific concentration&#160;of an inducer may not be able to report events occurring within the optimal concentration range to elicit the desired responses from a species. Semisolid plates containing multiple concentrations are commonly used to investigate the response within an inducer concentration range. However, separate semisolid plates increase variations in medium viscosity and moisture content within each plate due to nonuniform solidification time.
This paper describes a one-step method to simultaneously test surface swarming motility on a single gradient plate, where the isometrically arranged test wells allow the simultaneous acquisition of multiconcentration responses. In the present work, the surface swarming of Escherichia coli K12 and Pseudomonas aeruginosa PAO1 were evaluated in response to a concentration gradient of inducers such as resveratrol and arabinose. Periodically, the swarm morphologies were imaged using an imaging system to capture the entire surface swarming process.
The quantitative measurement of the swarm morphologies was acquired using ImageJ software, providing analyzable information of the swarm area. This paper presents a simple gradient swarm plate method that provides qualitative and quantitative information about the inducers&#39; effects on surface swarming, which can be extended to study the effects of other inducers on a broader range of motile bacterial species.

Here, we describe the use of inducer gradient plates to evaluate bacterial swarming motility while simultaneously obtaining multiple concentration responses.

Quantificazione della motilità dello sciame di superficie batterica su piastre gradienti induttori

Bacterial swarming motility is a common microbiological phenotype that bacterial communities use to migrate over semisolid surfaces. In investigations of ...

Biochimica

Motility of Single Molecules and Clusters of Bi-Directional Kinesin-5 Cin8 Purified from S. cerevisiae Cells

The mitotic bipolar kinesin-5 motors perform essential functions in spindle dynamics. These motors exhibit a homo-tetrameric structure with two pairs of catalytic motor domains, located at opposite ends of the active complex. This unique architecture enables kinesin-5 motors to crosslink and slide apart antiparallel spindle microtubules (MTs), thus providing the outwardly-directed force that separates the spindle poles apart. Previously, kinesin-5 motors were believed to be exclusively plus-end directed. However, recent studies revealed that several fungal kinesin-5 motors are minus-end directed at the single-molecule level and can switch directionality under various experimental conditions. The Saccharomyces cerevisiae kinesin-5 Cin8 is an example of such bi-directional motor protein: in high ionic strength conditions single molecules of Cin8 move in the minus-end direction of the MTs. It was also shown that Cin8 forms motile clusters, predominantly at the minus-end of the MTs, and such clustering allows Cin8 to switch directionality and undergo slow, plus-end directed motility. This article provides a detailed protocol for all steps of working with GFP-tagged kinesin-5 Cin8, from protein overexpression in S. cerevisiae cells and its purification to in vitro single-molecule motility assay. A newly developed method described here helps to differentiate between single molecules and clusters of Cin8, based on their fluorescence intensity. This method enables separate analysis of motility of single molecules and clusters of Cin8, thus providing the characterization of the dependence of Cin8 motility on its cluster size.

Motility of Single Molecules and Clusters of Bi-Directional Kinesin-5 Cin8 Purified from S. cerevisiae Cells

The bi-directional mitotic kinesin-5 Cin8 accumulates in clusters that split and merge during their motility. Accumulation in clusters also changes the velocity and directionality of Cin8. Here, a protocol for motility assays with purified Cin8-GFP and analysis of motile properties of single molecules and clusters of Cin8 is described.

Motilità di singole molecole e cluster di Kinesin-5 Cin8 bidirezionale purificata da cellule S. cerevisiae

The mitotic bipolar kinesin-5 motors perform essential functions in spindle dynamics. These motors exhibit a homo-tetrameric structure with two pairs of ...

Generating Controlled, Dynamic Chemical Landscapes to Study Microbial Behavior

We demonstrate a method for the generation of controlled, dynamic chemical pulses&#8213;where localized chemoattractant becomes suddenly available at the microscale&#8213;to create micro-environments for microbial chemotaxis experiments. To create chemical pulses, we developed a system to introduce amino acid sources near-instantaneously by photolysis of caged amino acids within a polydimethylsiloxane (PDMS) microfluidic chamber containing a bacterial suspension. We applied this method to the chemotactic bacterium, Vibrio ordalii, which can actively climb these dynamic chemical gradients while being tracked by video microscopy. Amino acids, rendered biologically inert (&#39;caged&#39;) by chemical modification with a photoremovable protecting group, are uniformly present in the suspension but not available for consumption until their sudden release, which occurs at user-defined points in time and space by means of a near-UV-A focused LED beam. The number of molecules released in the pulse can be determined by a calibration relationship between exposure time and uncaging fraction, where the absorption spectrum after photolysis is characterized by using UV-Vis spectroscopy. A nanoporous polycarbonate (PCTE) membrane can be integrated into the microfluidic device to allow the continuous removal by flow of the uncaged compounds and the spent media. A strong, irreversible bond between the PCTE membrane and the PDMS microfluidic structure is achieved by coating the membrane with a solution of 3-aminopropyltriethoxysilane (APTES) followed by plasma activation of the surfaces to be bonded. A computer-controlled system can generate user-defined sequences of pulses at different locations and with different intensities, so as to create resource landscapes with prescribed spatial and temporal variability. In each chemical landscape, the dynamics of bacterial movement at the individual scale and their accumulation at the population level can be obtained, thereby allowing the quantification of chemotactic performance and its effects on bacterial aggregations in ecologically relevant environments.

A protocol for the generation of dynamic chemical landscapes by photolysis within microfluidic and millifluidic setups is presented. This methodology is suitable to study diverse biological processes, including the motile behavior, nutrient uptake, or adaptation to chemicals of microorganisms, both at the single cell and population level.

Generazione di paesaggi chimici dinamici e controllati per studiare il comportamento microbico

We demonstrate a method for the generation of controlled, dynamic chemical pulses&#8213;where localized chemoattractant becomes suddenly available at the ...

Bioingegneria

Visualization of Bacterial Resistance using Fluorescent Antibiotic Probes

Fluorescent antibiotics are multipurpose research tools that are readily used for the study of antimicrobial resistance, due to their significant advantage over other methods. To prepare these probes, azide derivatives of antibiotics are synthesized, then coupled with alkyne-fluorophores using azide-alkyne dipolar cycloaddition by click chemistry. Following purification, the antibiotic activity of the fluorescent antibiotic is tested by minimum inhibitory concentration assessment. In order to study bacterial accumulation, either spectrophotometry or flow cytometry may be used, allowing for much simpler analysis than methods relying on radioactive antibiotic derivatives. Furthermore, confocal microscopy can be used to examine localization within the bacteria, affording valuable information about mode of action and changes that occur in resistant species. The use of fluorescent antibiotic probes in the study of antimicrobial resistance is a powerful method with much potential for future expansion.

Fluorescently tagged antibiotics are powerful tools that can be used to study multiple aspects of antimicrobial resistance. This article describes the preparation of fluorescently tagged antibiotics and their application to studying antibiotic resistance in bacteria. Probes can be used to study mechanisms of bacterial resistance (e.g., efflux) by spectrophotometry, flow cytometry, and microscopy.

Visualizzazione della resistenza batterica utilizzando sonde antibiotici fluorescenti

Fluorescent antibiotics are multipurpose research tools that are readily used for the study of antimicrobial resistance, due to their significant ...

Immunologia e infezioni

Kinetic Visualization of Single-Cell Interspecies Bacterial Interactions

Polymicrobial communities are ubiquitous in nature, yet studying their interactions at the single-cell level is difficult. Thus, a microscopy-based method has been developed for observing interspecies interactions between two bacterial pathogens. The use of this method to interrogate interactions between a motile Gram-negative pathogen, Pseudomonas aeruginosa and a non-motile Gram-positive pathogen, Staphylococcus aureus is demonstrated here. This protocol consists of co-inoculating each species between a coverslip and an agarose pad, which maintains the cells in a single plane and allows for visualization of bacterial behaviors in both space and time.
Furthermore, the time-lapse microscopy demonstrated here is ideal for visualizing the early interactions that take place between two or more bacterial species, including changes in bacterial species motility in monoculture and in coculture with other species. Due to the nature of the limited sample space in the microscopy setup, this protocol is less applicable for studying later interactions between bacterial species once cell populations are too high. However, there are several different applications of the protocol which include the use of staining for imaging live and dead bacterial cells, quantification of gene or protein expression through fluorescent reporters, and tracking bacterial cell movement in both single species and multispecies experiments.

This live-bacterial cell imaging protocol allows for visualization of interactions between multiple bacterial species at the single-cell level over time. Time-lapse imaging allows for observation of each bacterial species in monoculture or coculture to interrogate interspecies interactions in multispecies bacterial communities, including individual cell motility and viability.

Visualizzazione cinetica delle interazioni batteriche interspecie a uni cell

Polymicrobial communities are ubiquitous in nature, yet studying their interactions at the single-cell level is difficult. Thus, a microscopy-based method ...

Preparation, Imaging, and Quantification of Bacterial Surface Motility Assays

Bacterial surface motility, such as swarming, is commonly examined in the laboratory using plate assays that necessitate specific concentrations of agar and sometimes inclusion of specific nutrients in the growth medium. The preparation of such explicit media and surface growth conditions serves to provide the favorable conditions that allow not just bacterial growth but coordinated motility of bacteria over these surfaces within thin liquid films. Reproducibility of swarm plate and other surface motility plate assays can be a major challenge. Especially for more &#8220;temperate swarmers&#8221; that exhibit motility only within agar ranges of 0.4%-0.8% (wt/vol), minor changes in protocol or laboratory environment can greatly influence swarm assay results. &#8220;Wettability&#8221;, or water content at the liquid-solid-air interface of these plate assays, is often a key variable to be controlled. An additional challenge in assessing swarming is how to quantify observed differences between any two (or more) experiments. Here we detail a versatile two-phase protocol to prepare and image swarm assays. We include guidelines to circumvent the challenges commonly associated with swarm assay media preparation and quantification of data from these assays. We specifically demonstrate our method using bacteria that express fluorescent or bioluminescent genetic reporters like green fluorescent protein (GFP), luciferase (lux operon), or cellular stains to enable time-lapse optical imaging. We further demonstrate the ability of our method to track competing swarming species in the same experiment.

Swarming motility is influenced by physical and environmental factors. We describe a two-phase protocol and guidelines to circumvent the challenges commonly associated with swarm assay preparation and data collection. A macroscopic imaging technique is employed to obtain detailed information on swarm behavior that is not provided by current analysis techniques.

Preparazione, Imaging, e la quantificazione di Surface batterica motilità Assays

Bacterial surface motility, such as swarming, is commonly examined in the laboratory using plate assays that necessitate specific concentrations of agar ...

Biophysical Characterization of Flagellar Motor Functions

The role of flagellar motors in bacterial motility and chemotaxis is well-understood. Recent discoveries suggest that flagellar motors are able to remodel in response to a variety of environmental stimuli and are among the triggers for surface colonization and infections. The precise mechanisms by which motors remodel and promote cellular adaptation likely depend on key motor attributes. The photomultiplier-based bead-tracking technique presented here enables accurate biophysical characterization of motor functions, including adaptations in motor speeds and switch-dynamics. This approach offers the advantage of real-time tracking and the ability to probe motor behavior over extended durations. The protocols discussed can be readily extended to study flagellar motors in a variety of bacterial species.

Recent findings suggest that bacterial flagellar motors sense a variety of environmental signals and remodel in response. The bead-assays discussed here are expected to help explain the role of remodeling in cellular adaptation to environmental stressors.

Caratterizzazione biofisica delle funzioni flagellare a motore

The role of flagellar motors in bacterial motility and chemotaxis is well-understood. Recent discoveries suggest that flagellar motors are able to remodel ...

Investigating Flagella-Driven Motility in Escherichia coli by Applying Three Established Techniques in a Series

Motility is crucial to the survival and success of many bacterial species. Many methodologies exist to exploit motility to understand signaling pathways, to elucidate the function and assembly of flagellar parts, and to examine and understand patterns of movement. Here we demonstrate a combination of three of these methodologies. Motility in soft agar is the oldest, offering a strong selection for isolating gain-of-function suppressor mutations in motility-impaired strains, where motility is restored through a second mutation. The cell-tethering technique, first employed to demonstrate the rotary nature of the flagellar motor, can be used to assess the impact of signaling effectors on the motor speed and its ability to switch rotational direction. The &#8220;border-crossing&#8221; assay is more recent, where swimming bacteria can be primed to transition into moving collectively as a swarm. In combination, these protocols represent a systematic and powerful approach to identifying components of the motility machinery, and to characterizing their role in different facets of swimming and swarming. They can be easily adapted to study motility in other bacterial species.

Investigating Flagella-Driven Motility in Escherichia coli by Applying Three Established Techniques in a Series

Many bacteria use flagella-driven motility to navigate their environment and colonize favorable surroundings both individually and as a collective. Demonstrated here is the use of three established methods that exploit motility as a selection tool to identify components/pathways contributing to swimming and swarming motility.

Investigare la motilità guidata dalla Flagella in Escherichia coli applicando tre tecniche consolidate in una serie

Motility is crucial to the survival and success of many bacterial species. Many methodologies exist to exploit motility to understand signaling pathways, ...

Bacterial Co-Incubation Assay: A Fluorescence Microscopy-Based Technique to Visualize Intraspecific Bacterial Competition at the Single-Cell Level

Source: Smith, S., et al., <a href="https://app.jove.com/v/62851">Quantification of Interbacterial Competition using Single-Cell Fluorescence Imaging.</a> J. Vis. Exp. (2021).
This video demonstrates a fluorescence microscopy-based method to study bacterial competition at the single-cell level. This method provides insights into the structure and function of bacterial communities.

Saggio di co-incubazione batterica: una tecnica basata sulla microscopia a fluorescenza per visualizzare la competizione batterica intraspecifica a livello di singola cellula