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Abstract Bacteria utilize a cell density‐dependent communication system called quorum sensing (QS) to coordinate group behaviors. In Gram‐positive bacteria, QS involves the production of and response to auto‐inducing peptide (AIP) signaling molecules to modulate group phenotypes, including pathogenicity. As such, this bacterial communication system has been identified as a potential therapeutic target against bacterial infections. More specifically, developing synthetic modulators derived from the native peptide signal paves a new way to selectively block the pathogenic behaviors associated with this signaling system. Moreover, rational design and development of potent synthetic peptide modulators allows in depth understanding of the molecular mechanisms that drive QS circuits in diverse bacterial species. Overall, studies aimed at understanding the role of QS in microbial social behavior could result in the accumulation of significant knowledge of microbial interactions, and consequently lead to the development of alternative therapeutic agents to treat bacterial infectivity. In this review, we discuss recent advances in the development of peptide‐based modulators to target QS systems in Gram‐positive pathogens, with a focus on evaluating the therapeutic potential associated with these bacterial signaling pathways.
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Could Positive Feedback Enable Bacterial Pheromone Signaling To Coordinate Behaviors in Response to Heterogeneous Environmental Cues?
ABSTRACT Pheromone signaling (PS) underlies many important bacterial behaviors, yet its ecological functions remain unresolved. Because pheromone-mediated behaviors require high cell density, the term “quorum sensing” is widely used to describe and make sense of PS. However, while this term has unified and popularized the field, bacterial PS clearly has roles beyond census taking, and the complexities of PS circuits indicate broader functional capacities. Two common features of bacterial PS are its regulation in response to environmental conditions and positive-feedback loops. Combined, these could enable PS to coordinate quorum-dependent group behaviors in response to heterogeneous environmental cues. Particularly in PS systems where positive feedback is strong, cells that are relatively far from a stimulatory environment could be recruited to a group response. Testing this model will benefit from in situ examination of relevant environmental cues and PS outputs in cells across populations, with and without positive feedback, in heterogeneous environments.
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- Award ID(s):
- 1716232
- PAR ID:
- 10061675
- Date Published:
- Journal Name:
- mBio
- Volume:
- 9
- Issue:
- 3
- ISSN:
- 2150-7511
- Page Range / eLocation ID:
- e00098-18
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1128/mBio.00098-18
