98%
921
2 minutes
20
Quorum sensing (QS), a bacterial process that regulates population-scale behavior, is mediated by small signaling molecules, called autoinducers (AIs), that are secreted and perceived, modulating a "collective" phenotype. Because the autoinducer AI-2 is secreted by a wide variety of bacterial species, its "perception" cues bacterial behavior. This response is mediated by the (LuxS-regulated) operon that includes the AI-2 transporter LsrACDB and the kinase LsrK. We report that HPr, a phosphocarrier protein central to the sugar phosphotransferase system of , copurifies with LsrK. Cocrystal structures of an LsrK/HPr complex were determined, and the effects of HPr and phosphorylated HPr on LsrK activity were assessed. LsrK activity is inhibited when bound to HPr, revealing new linkages between QS activity and sugar metabolism. These findings help shed new light on the abilities of bacteria to rapidly respond to changing nutrient levels at the population scale. They also suggest new means of manipulating QS activity among bacteria and within various niches.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5983913 | PMC |
http://dx.doi.org/10.1126/sciadv.aar7063 | DOI Listing |
Med Int (Lond)
August 2025
Department of Epidemiology, School of Public Health, Zhengzhou University, Zhengzhou, Henan 450001, P.R. China.
Punicalagin, a polyphenolic compound extracted from pomegranate peel, has received increasing attention in recent years due to its antibacterial and antiviral properties. Punicalagin is capable of inhibiting bacterial growth at sub-inhibitory concentrations by affecting cell membrane formation, disrupting membrane integrity, altering cell permeability, affecting efflux pumps, interfering with quorum sensing and influencing virulence factors. Additionally, punicalagin inhibits viruses by modulating enzyme activity, interacting with viral surface proteins, affecting gene expression, blocking viral attachment, disrupting virus receptor interaction and inhibiting viral replication.
View Article and Find Full Text PDFRSC Adv
September 2025
Department of Pharmacognosy, Faculty of Pharmacy, Assiut University Assiut 71526 Egypt
Thunb is endogenous to Southeast Asia and traditionally used for the treatment of bacterial and viral infections. Previous studies reported various pharmacological activities, including cytotoxic activity. The aim of this work was to identify phytoconstituents of the ethanolic extract of aerial parts using extensive 1D- and 2D-NMR analysis and HR-MS.
View Article and Find Full Text PDFJ Mater Chem B
September 2025
State Key Laboratory of Bioactive Molecules and Druggability Assessment, Guangdong Basic Research Center of Excellence for Natural Bioactive Molecules and Discovery of Innovative Drugs, College of Pharmacy, Jinan University, Guangzhou 511436, China.
Globally, new antibiotic development lags behind the rapid evolution of antibiotic-resistant bacteria. Given the extensive research and development cycles, high costs, and risks associated with new pharmaceuticals, exploring alternatives to conventional antibiotics and enhancing their efficacy and safety is a promising strategy for addressing challenges in the post-antibiotic era. Previous studies have shown that antimicrobial peptides/peptidomimetics (AMPs) primarily use a membrane-disruption mechanism distinct from conventional antibiotics to exert bactericidal effects.
View Article and Find Full Text PDFGenome Biol
September 2025
Department of Biology, Plant-Microbe Interactions, Science for Life, Utrecht University, Utrecht, 3584CH, The Netherlands.
Background: Plant roots release root exudates to attract microbes that form root communities, which in turn promote plant health and growth. Root community assembly arises from millions of interactions between microbes and the plant, leading to robust and stable microbial networks. To manage the complexity of natural root microbiomes for research purposes, scientists have developed reductionist approaches using synthetic microbial inocula (SynComs).
View Article and Find Full Text PDFPLoS One
September 2025
Department of Microbiology and Parasitology, Faculty of Biology - Aquatic One Health Research Center (iARCUS), Universidade de Santiago de Compostela, Santiago de Compostela, Spain.
Uropathogenic Escherichia coli (UPEC) are among the first pathogens to colonise in catheter and non-catheter-associated urinary tract infections. However, these infections are often polymicrobial, resulting in multi-species infections that persist by forming biofilms. Living within these highly antimicrobial tolerant communities, bacteria can establish intra- and inter-specific interactions, including quorum sensing (QS)-mediated signalling mechanisms, which play a key role in biofilm establishment and maturation.
View Article and Find Full Text PDF