Stress adaptation and survival in Pseudomonas aeruginosa

点击翻译按钮获取中文摘要

The bacterium Pseudomonas aeruginosa is present nearly everywhere in natural and man-made environments. We study this bacteria because is it a model of highly adaptable bacteria capable of surviving many stresses. When bacteria, particularly Pseudomonas aeruginosa, are replicating slowly or not at all, they become very difficult to kill. Our research is focused on understanding how Pseudomonas aeruginosa protects itself against chemical stresses to survive, particularly when it is in a non-growing state and under nutrient limitation. We are particularly interested in understanding how Pseudomonas uses a stress response called the stringent response, to help adapt and survive under stress. The stringent response is activated when bacteria starve for nutrients or encounter various forms of external stress. It controls the expression of many genes and can reorganize the cell's functions and metabolism to promote survival. We have recently discovered that the stringent response signals to bacteria under stress to alter the permeability of cell membranes, and thus keep out toxic molecules. The goal of this research is to understand how bacteria alter their cell membrane during periods of slow replication and how this mechanism allows them to survive chemical stress such as antibiotics. Our research will help microbiologist better understand the survival mechanisms that bacteria have and why antibiotics may not effective at killing non-growing bacteria. This fundamental knowledge will help scientists discover new ways to improve antibacterial treatments of the future.