Evidence map›Paper›PMID 42207781›Full record

ArticlePLoS pathogens2026

LuxS/AI-2 regulates phoP/phoQ by a non-canonical mechanism to enhance acid stress survival in Salmonella Typhimurium.

Anmol Singh, Abhilash Vijay Nair, Shashanka Aroli, Suman Das, Subhrajit Karmakar, Raju S Rajmani, Santanu Mukherjee, Umesh Varshney, Dipshikha Chakravortty

Abstract read
In one paragraph

Article in PLoS pathogens, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

0numbers the graph read from it
0cells of the map it votes in
1citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

1 citing paper in PubMed.

  1. Article
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

9 authors.

Anmol SinghDepartment of Microbiology and Cell Biology, Division of Biological Sciences, Indian Institute of Science, Bengaluru, India.
Abhilash Vijay NairDepartment of Microbiology and Cell Biology, Division of Biological Sciences, Indian Institute of Science, Bengaluru, India.
Shashanka AroliDepartment of Microbiology and Cell Biology, Division of Biological Sciences, Indian Institute of Science, Bengaluru, India.
Suman DasDepartment of Organic Chemistry, Indian Institute of Science, Bengaluru, India.
Subhrajit KarmakarDepartment of Organic Chemistry, Indian Institute of Science, Bengaluru, India.
Raju S RajmaniMolecular Biophysics Unit, Indian Institute of Science, Bengaluru, India.
Santanu MukherjeeMolecular Biophysics Unit, Indian Institute of Science, Bengaluru, India.
Umesh VarshneyDepartment of Microbiology and Cell Biology, Division of Biological Sciences, Indian Institute of Science, Bengaluru, India.
Dipshikha ChakravorttyDepartment of Microbiology and Cell Biology, Division of Biological Sciences, Indian Institute of Science, Bengaluru, India.ORCID https://orcid.org/0000-0002-7838-5145

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

The intestinal milieu is largely characterized by the complex array of chemical compounds produced through the metabolic activity of resident microbiota. Enteric pathogens like Salmonella, which have evolved refined mechanisms to persist within this environment, utilize these microbial metabolites and self-produce quorum molecules as molecular cues to identify ecological niches and modulate their survival and virulence strategies. Salmonella quorum sensing involves producing and detecting universal Autoinducer-2 (AI-2) signaling molecules. Our research reveals that Salmonella Typhimurium enhances AI-2 biosynthesis and transport under acidic conditions, aiding environmental adaptation and facilitating pathogenesis in macrophages. AI-2 signaling regulates the pH-sensing two-component system genes, phoP/phoQ, ensuring cytosolic pH homeostasis, survival, and acid tolerance. It also involves regulating the lysine/cadaverine-mediated acid tolerance response and maintaining bacterial cytosolic pH. Furthermore, we investigated the mechanism of AI-2-mediated gene regulation and demonstrated that, in addition to the lsr promoter, the repressor LsrR binds the phoP promoter via its Y25 and R43 residues, thereby negatively regulating phoP expression. Additionally, this signaling ameliorates the intracellular survival by modulating Salmonella Pathogenicity Island-2 (SPI-2) regulators (ssrA/ssrB) and SPI-2 effector expression via PhoP. Mouse models demonstrate that AI-2 signaling is essential for colonizing the primary and secondary infection sites. Therefore, quorum sensing facilitates survival in hostile host environments by modulating multiple genetic targets through the AI-2/LsrR-mediated feedback loop in pathogenic bacteria.

Indexed as

Bacterial ProteinsCarbon-Sulfur LyasesHomoserineLactonesSalmonella typhimuriumAnimalsGene Expression Regulation, BacterialHydrogen-Ion ConcentrationMiceQuorum SensingSalmonella InfectionsSignal TransductionStress, PhysiologicalVirulenceBacterial ProteinsCarbon-Sulfur LyasesHomoserineLactonesLuxS protein, BacteriaN-octanoylhomoserine lactonePhoP protein, BacteriaPhoQ protein, Bacteria

Identifiers

PMID42207781
PMCPMC13218499

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.