Pseudomonas aeruginosa culture. Credit: Sun
Key points:
- Bacteria’s resting state is dangerous because it helps them evade antibiotics and contribute to chronic infections.
- Researchers found that long chains of molecules called polyphosphates (polyp) are required for bacteria to slow down and enter the resting state.
- Preventing cells from producing polyP may help treat chronic infections in which slow-growing bacteria evade antibiotics.
Disease-causing bacteria are dangerous due to their rapid growth. However, bacteria’s resting state can be just as dangerous because it helps them evade antibiotics and contribute to severe chronic infections. Now, new research, published in Proceedings of the National Academy of Sciences, finds that long chains of molecules called polyphosphates (polyP) are essential for bacteria’s resting state.
Researchers used Pseudomonas aeruginosa to study polyP dynamics. Starving P. aeruginosa of nitrogen results in significant production of polyP and the team discovered that a mutant unable to make polyP cannot enter its resting state.
To better understand the relationship between polyP and the resting state, the team genetically engineered P. aeruginosa to make small, labeled particles that allowed them to track how molecules moved within the bacteria. They found that starving the bacteria of nutrients slowed the movement of materials within the interior of P. aeruginosa and prevented division. Conversely, without nitrogen and polyP, the bacteria moved materials around at top speed, became bigger, loosened their genetic material, and continued dividing.
The team determined that polyP is likely responsible for helping bacteria species slow down. They hypothesize that preventing cells from producing polyP would keep them active and make them vulnerable to antibiotic treatment.
Overall, the insights into the polyP mechanisms underlying the resting state may lead to new ways of treating chronic infections that are not responsive to typical antibiotics.
“This not only helps point in possible directions for treating pathogenic bacteria, but also reveals answers for fundamental questions about how things diffuse throughout a bacterial cell,” said senior author Lisa Racki, professor at Scripps Research.