2024-10-23 カリフォルニア工科大学(Caltech)
<関連情報>
- https://www.caltech.edu/about/news/new-technology-illustrates-bacterial-hibernation-states
- https://www.cell.com/cell/abstract/S0092-8674(24)01142-5
ハイスループット電気化学を用いた細菌の低電力維持状態のメカニズム研究 Mechanistic study of a low-power bacterial maintenance state using high-throughput electrochemistry
John A. Ciemniecki∙ Chia-Lun Ho∙ Richard D. Horak∙ Akihiro Okamoto∙ Dianne K. Newman
Cell Published:October 23, 2024
DOI:https://doi.org/10.1016/j.cell.2024.09.042
Graphical abstract
Highlights
•Anaerobic PCN cycling supports a low metabolic rate (∼103 ATP s-1 cell-1 at 25°C)
•During PCN cycling, single cells maintain metabolic activity but do not grow
•A high-throughput electrochemical platform enables mechanistic studies of maintenance
•Disrupting membrane integrity or bioenergetic components impairs survival in this state
Summary
Mechanistic studies of life’s lower metabolic limits have been limited due to a paucity of tractable experimental systems. Here, we show that redox-cycling of phenazine-1-carboxamide (PCN) by Pseudomonas aeruginosa supports cellular maintenance in the absence of growth with a low mass-specific metabolic rate of 8.7 × 10-4 W (g C)-1 at 25°C. Leveraging a high-throughput electrochemical culturing device, we find that non-growing cells cycling PCN tolerate conventional antibiotics but are susceptible to those that target membrane components. Under these conditions, cells conserve energy via a noncanonical, facilitated fermentation that is dependent on acetate kinase and NADH dehydrogenases. Across PCN concentrations that limit cell survival, the cell-specific metabolic rate is constant, indicating the cells are operating near their bioenergetic limit. This quantitative platform opens the door to further mechanistic investigations of maintenance, a physiological state that underpins microbial survival in nature and disease.
