Racing Bacterial Cells in Microfluidic Gradients

1. Racing Bacterial Cells in Microfluidic Gradients in order to measure chemotactic efficiency of isogenic bacteria population in correlation to their morphology

2. Racing Bacterial Cells in Microfluidic Gradients in order to measure chemotactic efficiency of isogenic bacteria population in correlation to their morphology Why: Length variation is observed in isogenic bacteria population

3. Racing Bacterial Cells in Microfluidic Gradients in order to measure chemotactic efficiency of isogenic bacteria population in correlation to their morphology Why: Length variation is observed in isogenic bacteria population Does length variation have any functional role? → e.g. enhanced/diminshed motility?

4. Racing Bacterial Cells in Microfluidic Gradients in order to measure chemotactic efficiency of isogenic bacteria population in correlation to their morphology Why: Length variation is observed in isogenic bacteria population Does length variation have any functional role? → e.g. enhanced/diminshed motility? Aim: Physical model of how cell size and number of flagella relate to swimming speeds and efficiency in chemotaxis

5. How: Build microfluidics chamber using PDMS based soft-lithography

6. How: Build microfluidics chamber using PDMS based soft-lithography Create nutrition gradient in chamber to induce chemotaxis (adding sugar) → Quantitative measurement of gradient by adding dye in same conc. → Simulating gradient with physics modeling program chemoattractant bacteria

7. How: Build microfluidics chamber using PDMS based soft-lithography Create nutrition gradient in chamber to induce chemotaxis (adding sugar) → Quantitative measurement of gradient by adding dye in same conc. → Simulating gradient with physics modeling program Recording bacterias with DIC timelapse microscopy Identify single cells and measure their motion tracks (Matlab) as well as size chemoattractant bacteria

8. How: Build microfluidics chamber using PDMS based soft-lithography Create nutrition gradient in chamber to induce chemotaxis (adding sugar) → Quantitative measurement of gradient by adding dye in same conc. → Simulating gradient with physics modeling program Recording bacterias with DIC timelapse microscopy Identify single cells and measure their motion tracks (Matlab) as well as size

9. Build microfluidics chamber using PDMS based soft-lithography Create nutrition gradient in chamber to induce chemotaxis (adding sugar) → Quantitative measurement of gradient by adding dye in same conc. → Simulating gradient with physics modeling program Recording bacterias with DIC timelapse microscopy Identify single cells and measure their motion tracks (Matlab) as well as size ~1.5 µm thickness ~ 3 µm spacing

11. Positions of tracked beads