Imaging and Quantifying Swarm Avoidance Responses to Antibiotic Stress in Pseudomonas aeruginosa

Take a swarming agar plate that supports swarming motility- a coordinated bacterial movement across a semisolid surface that forms tendril-like patterns.

Inoculate the plate’s center with a Pseudomonas aeruginosa culture and place a mixture of the same culture with an antibiotic at evenly spaced satellite positions.

Cover the plate with a black-painted lid to minimize light reflections.

Place the plate on a flatbed scanner inside an incubator maintained at optimal humidity.

During incubation, the central population begins to multiply and swarm.

As the swarm approaches the antibiotic-treated colonies, it detects stress signals secreted by the bacteria and redirects to avoid these regions.

The scanner, controlled by automated software, captures high-resolution images at regular intervals.

Compile these images into a video to visualize swarm progression and avoidance over time.

Quantify swarm avoidance by measuring the distance from each satellite colony to the edge of the central swarm in a late-stage image.

After placing the plates into the scanner, open file and save settings to set the saving path for the images and click scan and OK at 30-minute intervals. To automate the image acquisitio