Intracellular acidification is a hallmark of thymineless death in E. coli

Area of Science:

• Microbiology
• Molecular Biology
• Biochemistry

Background:

• Thymidine starvation induces rapid cell death, a process termed thymineless death (TLD).
• TLD is the mechanism of action for various antimicrobial and antineoplastic drugs.
• The precise causal events leading to TLD remain poorly understood despite extensive research.

Purpose of the Study:

• To systematically identify the genetic and regulatory factors contributing to TLD in Escherichia coli.
• To elucidate the mechanistic sequence of events culminating in TLD.

Main Methods:

• Employed a diverse array of unbiased genetic and molecular approaches.
• Investigated gene function and regulatory networks associated with TLD.
• Utilized chemical and genetic perturbations to modulate intracellular pH.

Main Results:

• Discovered novel genes involved in TLD pathways.
• Identified intracellular acidification as a critical and previously unrecognized early event in TLD.
• Demonstrated that acidification is a causal factor in TLD, as increasing intracellular pH reduced cell death.
• Observed intracellular pH decrease upon gentamicin exposure, suggesting a role in antibiotic action.

Conclusions:

• Intracellular acidification is a crucial and causal event in thymineless death in Escherichia coli.
• This finding provides new mechanistic insight into TLD.
• Intracellular acidification may represent a common pathway for the bactericidal effects of certain antibiotics.