The Potential for Redox-Active Metabolites To Enhance or Unlock Anaerobic Survival Metabolisms in Aerobes

Abstract

Classifying microorganisms as “obligate” aerobes has colloquially implied death without air, leading to the erroneous assumption that, without oxygen, they are unable to survive. However, over the past few decades, more than a few obligate aerobes have been found to possess anaerobic energy conservation strategies that sustain metabolic activity in the absence of growth or at very low growth rates. Similarly, studies emphasizing the aerobic prowess of certain facultative aerobes have sometimes led to underrecognition of their anaerobic capabilities. Yet an inescapable consequence of the affinity both obligate and facultative aerobes have for oxygen is that the metabolism of these organisms may drive this substrate to scarcity, making anoxic survival an essential skill. To illustrate this, we highlight the importance of anaerobic survival strategies forPseudomonas aeruginosaandStreptomyces coelicolor, representative facultative and obligate aerobes, respectively. Included among these strategies, we describe a role for redox-active secondary metabolites (RAMs), such as phenazines made byP. aeruginosa, in enhancing substrate-level phosphorylation. Importantly, RAMs are made by diverse bacteria, often during stationary phase in the absence of oxygen, and can sustain anoxic survival. We present a hypothesis for how RAMs may enhance or even unlock energy conservation pathways that facilitate the anaerobic survival of both RAM producers and nonproducers.

Document Details

Document Type
Pub Defense Publication
Publication Date
Feb 18, 2020
Source ID
10.1128/jb.00797-19

Entities

People

  • Dianne Newman
  • John A Ciemniecki

Organizations

  • Army Research Office
  • National Institutes of Health

Tags

Fields of Study

  • Biology
  • Environmental science

Readers

  • Economics
  • Microbial Pathology