Session 2D: Visualizing Bacterial Persistence and Antibiotic Survival in B. subtilis
Session Number
Session 2D:3rd Presentation
Advisor(s)
Jade Wang, University of Wisconsin-Madison
Location
Room A155
Start Date
28-4-2017 10:00 AM
End Date
28-4-2017 11:15 AM
Abstract
Guanosine penta/tetraphosphate ((p)ppGpp) is a widely conserved intracellular signaling molecule that plays important roles in metabolic control and stress response in bacteria. Biosynthesis of ppGpp is known to be triggered by various starvation stresses, most notably amino acids starvation. However, the dynamics of ppGpp production in bacterial cells and their effects on stress survival have not been fully explored. Using Bacillus subtilis as the model organism, the work of this study aimed to employ a fluorescence-based reporter to study ppGpp production in live bacteria at both single-cell and populational levels, and how it affects bacterial survival to lethal stresses. Single-cell time-lapse microscopy analysis and fluorescence microplate assays were used to study spontaneous or antibioticinduced induction of ppGpp, and cell viability assays were used to study the effects of ppGpp induction on survival against lethal antibiotic treatments and through cell dormancy (persistence). ppGpp production can occur spontaneously within a population at single-cell level, as well as modestly inducible by various antibiotics at populational level and that rapid ppGpp induction causes development of dormant cells. Cells with induced ppGpp levels are also significantly more tolerant to lethal antibiotic treatments, indicating that this signal molecule plays an important role in stress survival.
Session 2D: Visualizing Bacterial Persistence and Antibiotic Survival in B. subtilis
Room A155
Guanosine penta/tetraphosphate ((p)ppGpp) is a widely conserved intracellular signaling molecule that plays important roles in metabolic control and stress response in bacteria. Biosynthesis of ppGpp is known to be triggered by various starvation stresses, most notably amino acids starvation. However, the dynamics of ppGpp production in bacterial cells and their effects on stress survival have not been fully explored. Using Bacillus subtilis as the model organism, the work of this study aimed to employ a fluorescence-based reporter to study ppGpp production in live bacteria at both single-cell and populational levels, and how it affects bacterial survival to lethal stresses. Single-cell time-lapse microscopy analysis and fluorescence microplate assays were used to study spontaneous or antibioticinduced induction of ppGpp, and cell viability assays were used to study the effects of ppGpp induction on survival against lethal antibiotic treatments and through cell dormancy (persistence). ppGpp production can occur spontaneously within a population at single-cell level, as well as modestly inducible by various antibiotics at populational level and that rapid ppGpp induction causes development of dormant cells. Cells with induced ppGpp levels are also significantly more tolerant to lethal antibiotic treatments, indicating that this signal molecule plays an important role in stress survival.