2026-09-21T16:22:11Z https://www.ideals.illinois.edu/oai-pmh

oai:www.ideals.illinois.edu:2142/129557 2026-02-05 col_2142_5131 col_2142_14795 com_2142_5130 com_2142_14794 com_2142_14793 com_2142_8903

application/pdf en text Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2027-05-01 The student, Gilberto Padron, accepted the attached license on 2025-04-22 at 08:56. The student, Gilberto Padron, submitted this Dissertation for approval on 2025-04-22 at 09:03. This Dissertation was approved for publication on 2025-04-22 at 15:04. DSpace SAF Submission Ingestion Package generated from Vireo submission #21881 on 2025-10-19 at 19:15:23 Shear flow modulates oxidative and nutrient stress in Pseudomonas aeruginosa Padron, Gilberto C. 2025-04-22 Sanfilippo, Joseph E Sanfilippo, Joseph E van der Donk, Wilfred Imlay, James A Wu, Nicholas C microfluidics microbiology biophysics eng Batch cell culture is one of the primary methods used to study bacterial stress responses in traditional laboratory experiments. Batch culture is limited, however, in its ability to consider dynamic features commonly found in natural systems such as shear flow. By using microfluidics and single cell microscopy, I can subject Pseudomonas aeruginosa to flow and chemical stress simultaneously. In batch culture, bacteria are capable of rapidly depleting certain stressors and nutrients. In microfluidic conditions, I demonstrate that cells are unable to deplete stressors or nutrients faster than they can be replenished. Here, I demonstrate that under flow, cells are sensitized to concentrations of the chemical stressor H2O2 100 to 1,000 times lower than in batch culture. I further observed that in nutrient limited conditions, flow can sustain growth at concentrations of glucose 1,000 times lower than in batch. Thus, based on my findings I suggest a shift in the thinking of concentrations required to elicit or alleviate chemical stress. More broadly, I emphasize the need for considering flow to better understand how bacterial pathogens may function in their natural environments. 2025-05 Thesis https://hdl.handle.net/2142/129557 Copyright 2025 Gilberto Padron Biochemistry Biochemistry University of Illinois Urbana-Champaign Ph.D. Dissertation