About

Bonnie L. Bassler is a member of the National Academy of Sciences and the American Academy of Arts and Sciences. She is a Howard Hughes Medical Institute Investigator, the Andrew K. Golden University Professor, and the Squibb Professor of Molecular Biology at Princeton University. Her research focuses on the molecular mechanisms that bacteria use for intercellular communication, specifically through a process called quorum sensing. This process allows bacteria to communicate using secreted chemical signaling molecules called autoinducers, enabling a population of bacteria to regulate gene expression collectively and coordinate behaviors such as bioluminescence, secretion of virulence factors, sporulation, and conjugation. Bassler's work has shown that bacteria like Vibrio harveyi and Vibrio cholerae produce different autoinducers, which are detected by sensor proteins that transduce information via phosphorylation/dephosphorylation cascades, with small RNA chaperone proteins acting as regulatory switches in these cascades. Her research has elucidated the biosynthetic pathways and structural details of AI-2 signaling molecules, revealing their widespread presence and role in inter-species bacterial communication. Her scientific contributions are paving the way for developing novel antimicrobial therapies aimed at disrupting quorum sensing to combat bacterial virulence. Bassler has received numerous awards and honors, including the MacArthur Foundation Fellowship, the National Medal of Science, and the Gairdner International Award, among others. She has also held leadership roles in scientific organizations and serves as an editor for prominent scientific journals.

Research topics

• Biology
• Materials science
• Genetics
• Biophysics
• Physics
• Psychology
• Quantum mechanics
• Cell biology
• Chemistry
• Nanotechnology
• Mechanics
• Microbiology
• Cognitive science
• Ecology

Selected publications

• Scripts and supplementary dataset used in study titled: A transcription factor-sRNA-mediated double-negative feedback loop confers pathogen-specific control of quorum-sensing genes

  Zenodo (CERN European Organization for Nuclear Research) · 2026-03-27

  otherOpen accessSenior author

  Custom scripts and Supplementary Dataset S1, containing RNA-sequencing results

  PublisherDOI

• Scripts and supplementary dataset used in study titled: A transcription factor-sRNA-mediated double-negative feedback loop confers pathogen-specific control of quorum-sensing genes

  Zenodo (CERN European Organization for Nuclear Research) · 2026-03-27

  otherOpen accessSenior author

  Custom scripts and Supplementary Dataset S1, containing RNA-sequencing results

  PublisherDOI

• A National Survey: Trends in U.S. Postpartum Pumping Practices After Term Deliveries

  Breastfeeding Medicine · 2025-11-08 · 1 citations

  article

  Background: Early and regular pump use is increasingly observed in clinical practice. The prevalence, motives, and clinical impact of these practices remain poorly understood. We aim to characterize pump use initiation, intensity, motivations, and challenges following U.S. term deliveries. Methods: This cross-sectional study used online survey data from U.S. individuals who delivered a term infant within the previous 13 months and ever provided pumped breast milk to their infant. Descriptive analyses characterize participant demographics, pump use initiation, intensity, motivations, and challenges. Chi-square tests compare key experiences between individuals who pumped above versus below the sample’s median pumping sessions per day. Results: We included 877 individuals from 49 states with median maternal and infant ages of 30 years and 6 months, respectively. Most participants (73%) were providing pumped milk to their infant currently. Pumping was most often initiated on day-of-delivery (38%); 67% initiated pumping by day 3 postpartum. Most participants (72%) had a pumping schedule; a median of four daily pumping sessions was reported. Breastfeeding challenges that motivated pumping included issues with supply (51%), engorgement (38%), and latch (26%). Participants also experienced oversupply (25%) and mastitis (15%). Stress/fatigue (40%) was a top pumping-related challenge. Those who pumped ≥4 times daily felt significantly more upset about discarding breast milk compared with those who pumped <4 times daily (22% vs.15%, p = 0.03). Conclusions: Among our participants with term infants, shifts toward early (day-of-delivery) and regular (routine or scheduled) postpartum pumping practices were observed. Examination of how early and/or regular pumping influences breastfeeding outcomes and maternal well-being following term deliveries is needed.

  PublisherDOI

• Analysis of gene expression within individual cells reveals spatiotemporal patterns underlying Vibrio cholerae biofilm development

  PLoS Biology · 2025-05-16 · 2 citations

  articleOpen accessSenior author

  Bacteria commonly exist in multicellular, surface-attached communities called biofilms. Biofilms are central to ecology, medicine, and industry. The Vibrio cholerae pathogen forms biofilms from single founder cells that, via cell division, mature into three-dimensional structures with distinct, yet reproducible, regional architectures. To define mechanisms underlying biofilm developmental transitions, we establish a single-molecule fluorescence in situ hybridization (smFISH) approach that enables accurate quantitation of spatiotemporal gene-expression patterns in biofilms at cell-scale resolution. smFISH analyses of V. cholerae biofilm regulatory and structural genes demonstrate that, as biofilms mature, overall matrix gene expression decreases, and simultaneously, a pattern emerges in which matrix gene expression becomes largely confined to peripheral biofilm cells. Both quorum sensing and c-di-GMP-signaling are required to generate the proper temporal pattern of matrix gene expression. Quorum sensing signaling is uniform across the biofilm, and thus, c-di-GMP-signaling alone sets the regional matrix gene expression pattern. The smFISH strategy provides insight into mechanisms conferring particular fates to individual biofilm cells.

  PublisherDOI

• A family of linear plasmid phages that detect a quorum-sensing autoinducer exists in multiple bacterial species

  bioRxiv (Cold Spring Harbor Laboratory) · 2025-07-30 · 1 citations

  preprintOpen accessSenior authorCorresponding

  ABSTRACT Temperate phages oscillate between lysogeny, a genomic maintenance state within a bacterial host, and lytic replication, in which the host is killed, and newly made phage particles are released. Successful transmission to new hosts requires that temperate phages appropriately time their transitions from lysogeny to lysis. It is well understood that temperate phages trigger lysis upon detection of host cell stress. Understanding of the breadth of cues that induce lysis expanded with the discovery of phages carrying quorum-sensing receptor genes that promote lytic induction exclusively at high host cell density. Bacteria engage in a cell-cell communication process called quorum sensing, which relies on the production, release, accumulation, and group-wide detection of extracellular signal molecules called autoinducers. Bacteria use quorum sensing to monitor changes in population density and synchronize collective behaviors. The temperate phage VP882 (φVP882) encodes VqmAφ – a homolog of its host’s quorum-sensing receptor/transcription factor VqmA. VqmAφ allows φVP882 to detect the accumulation of the host autoinducer called DPO. Presumably, launching the lytic induction program at high host cell density maximizes φVP882 transmission to new hosts. Here, by mining sequence databases for linear plasmid phages, we identify VP882-like phages in multiple DPO-producing bacterial species isolated at diverse times and geographic locations. We show that the VqmAφ homologs can indeed detect DPO and, in response, activate the lytic pathway. Our observation indicates that φVP882 is a member of a large family of globally-dispersed quorum-sensing-responsive temperate phages. IMPORTANCE The discovery of quorum-sensing responsive linear plasmid phages has transformed understanding of phage-bacterial interactions by demonstrating inter-domain chemical communication. To date, however, examples of quorum-sensing responsive phages have been sparse. The founding example of such a phage, φVP882, detects a chemical communication signal molecule called DPO that is produced by diverse bacterial species. We investigated whether a family of VP882-like phages might exist that detect and respond to DPO. We find that indeed, VP882-like phages reside in DPO-producing bacterial species isolated at different times and geographic locations, suggesting their wide circulation in the environment. This observation strengthens the evidence for the generality of phage-bacterial inter-domain chemical communication.

  PublisherOA PDFDOI

• A transcription factor-sRNA-mediated double-negative feedback loop confers pathogen-specific control of quorum-sensing genes

  bioRxiv (Cold Spring Harbor Laboratory) · 2025-08-22 · 1 citations

  preprintOpen accessSenior author

  Abstract The cell-to-cell communication process called quorum sensing enables bacteria to synchronize collective behaviors. Quorum sensing relies on the production, release, and detection of signaling molecules called autoinducers. In Vibrio cholerae , the VqmA transcription factor, following binding of the DPO autoinducer, activates expression of the gene encoding the VqmR small regulatory RNA. VqmR controls traits including biofilm formation. Here, we identify repressors of DPO-VqmA-VqmR signaling. We focus on one identified repressor, the LuxT transcription factor. We show that LuxT represses vqmR transcription. VqmR post-transcriptionally represses luxT translation. This arrangement forms a double-negative feedback loop between the two regulators. Reciprocal control hinges on the N-terminal 8 amino acids of LuxT. The nucleotide sequence encoding this LuxT region serves as the VqmR binding site in the luxT mRNA and the amino acids specified by this same N-terminal region are required for LuxT to bind the vqmR promoter. This same LuxT N-terminal region also expands the DNA motifs to which LuxT can bind. We show this regulatory circuit is unique to V. cholerae and closely related species and absent from other vibrios. We define the set of LuxT-controlled genes in V. cholerae and show that LuxT promotes biofilm formation, a key requirement for successful colonization of eukaryotic hosts. Importance Bacterial quorum sensing enables control of collective behaviors. In Vibrio cholerae , the DPO-VqmA-VqmR quorum-sensing circuit governs key processes, including biofilm formation. Here, we identify a double-negative feedback loop between the transcription factor LuxT and the small RNA VqmR. This regulatory circuit depends on an eight amino acid N-terminal region that exists only in V. cholerae LuxT and LuxT from its close relatives. This short peptide sequence confers three distinct functions: It enables LuxT to repress vqmR , renders luxT mRNA susceptible to VqmR repression, and governs which DNA motifs LuxT can bind. Our findings reveal a pathogen-specific regulatory module that links small RNA targeting of mRNAs to transcription factor DNA binding specificity. The results show how evolution tailors bacterial regulatory circuits to adapt to different environments.

  PublisherOA PDFDOI

• Food-Derived Compounds Extend the Shelf Life of Frozen Human Milk

  Foods · 2025-06-07 · 1 citations

  articleOpen accessSenior authorCorresponding

  Breastmilk is known to provide optimal nutrition for infant growth and development. A cross-sectional analysis of nationally representative US data from 2016 to 2021 revealed that >90% of lactating mothers reported using breast pumps to express milk. We conducted a survey of n = 1049 lactating or recently lactating individuals from a US nationally representative population to explore breastmilk storage practices among this group. The data revealed that 83% of respondents store breastmilk in their homes, with 68% using freezers to do so for >1 month. The lowest available temperature in most household freezers is −20 °C, a temperature that is inadequate to maintain human milk’s emulsified structure, leading to separation, degradation of fats, loss of key vitamins, and changes in palatability. We developed a first-of-its-kind high-throughput screening platform to identify food-derived compounds and combinations of compounds that, when added to human breastmilk, preserve fat content, retain antioxidant capacity, and reduce production of rancid-associated free fatty acids during extended freezer storage. Our screening identified pectin (0.5% w/v) and ascorbic acid (100 μg/mL) as optimal preservation agents. Compared to untreated controls, this formulation reduced glycerol production by approximately 60% and maintained antioxidant capacity after 6 months of storage at −20 °C. Lysozyme and protease activity were maintained at >75% of the levels in fresh breastmilk. This formulation represents a lead for the development of safe and affordable frozen breastmilk shelf-life extenders for at-home use to increase the longevity of stored breastmilk.

  PublisherOA PDFDOI

• Inhibitors of the PqsR Quorum-Sensing Receptor Reveal Differential Roles for PqsE and RhlI in Control of Phenazine Production

  bioRxiv (Cold Spring Harbor Laboratory) · 2025-02-11 · 1 citations

  preprintOpen accessSenior authorCorresponding

  Abstract Pseudomonas aeruginosa is a leading cause of hospital-acquired infections and it is resistant to many current antibiotic therapies, making development of new anti-microbial treatments imperative. The cell-to-cell communication process called quorum sensing controls P. aeruginosa pathogenicity. Quorum sensing relies on the production, release, and group-wide detection of extracellular signal molecules called autoinducers. Quorum sensing enables bacteria to synchronize group behaviors. P. aeruginosa possesses multiple quorum-sensing systems that control overlapping regulons, including those required for virulence and biofilm formation. Interventions that target P. aeruginosa quorum-sensing receptors are considered a fruitful avenue to pursue for new therapeutic advances. Here, we developed a P. aeruginosa strain that carries a bioluminescent reporter fused to a target promoter that is controlled by two P. aeruginosa quorum-sensing receptors. The receptors are PqsR, which binds and responds to the autoinducer called PQS (2-heptyl-3-hydroxy-4(1H)-quinolone) and RhlR, which binds and responds to the autoinducer called C4-HSL (C4-homoserine lactone). We used this reporter strain to screen >100,000 compounds with the aim of identifying inhibitors of either or both the PqsR and RhlR quorum-sensing receptors. We report results for 30 PqsR inhibitors from this screen. All of the identified compounds inhibit PqsR with IC 50 values in the nanomolar to low micromolar range and they are readily docked into the autoinducer binding site of the PqsR crystal structure, suggesting they function competitively. The majority of hits identified are not structurally related to previously reported PqsR inhibitors. Recently, RhlR was shown to rely on the accessory protein PqsE for full function. Specifically, RhlR controls different subsets of genes depending on whether it is bound to PqsE or to C4-HSL, however, the consequences of differential regulation on the quorum-sensing output response have not been defined. PqsR regulates pqsE . That feature of the system enabled us to exploit our new set of PqsR inhibitors to show that RhlR requires PqsE to activate the biosynthetic genes for pyocyanin, a key P. aeruginosa virulence factor, while C4-HSL is dispensable. These results highlight the promise of inhibition of PqsR as a possible P. aeruginosa therapeutic to suppress production of factors under RhlR-PqsE control.

  PublisherOA PDFDOI

• A family of linear plasmid phages that detect a quorum-sensing autoinducer exists in multiple bacterial species

  mBio · 2025-12-12 · 3 citations

  articleOpen accessSenior author

  Temperate phages oscillate between lysogeny, a genomic maintenance state within a bacterial host, and lytic replication, in which the host is killed, and newly made phage particles are released. Successful transmission to new hosts requires that temperate phages appropriately time their transitions from lysogeny to lysis. It is well understood that temperate phages trigger lysis upon detection of host cell stress. Understanding of the breadth of cues that induce lysis expanded with the discovery of phages carrying quorum-sensing receptor genes that promote lytic induction exclusively at high host cell density. Bacteria engage in a cell-cell communication process called quorum sensing, which relies on the production, release, accumulation, and group-wide detection of extracellular signal molecules called autoinducers. Bacteria use quorum sensing to monitor changes in population density and synchronize collective behaviors. The temperate phage VP882 (φVP882) encodes VqmAφ-a homolog of its host's quorum-sensing receptor/transcription factor VqmA. VqmAφ allows φVP882 to detect the accumulation of the host autoinducer called DPO. Presumably, launching the lytic induction program at high host cell density maximizes φVP882 transmission to new hosts. Here, by mining sequence databases for linear plasmid phages, we identify VP882-like phages in multiple DPO-producing bacterial species isolated at diverse times and geographic locations. We show that the VqmAφ homologs can indeed detect DPO and, in response, activate the lytic pathway. Our findings indicate that φVP882 is a member of a family of globally dispersed temperate phages that possess the potential to respond to host quorum sensing. IMPORTANCE: The discovery of quorum-sensing responsive linear plasmid phages has transformed understanding of phage-bacterial interactions by demonstrating inter-domain chemical communication. To date, however, examples of quorum-sensing responsive phages have been sparse. The founding example of such a phage, φVP882, detects a chemical communication signal molecule called DPO that is produced by diverse bacterial species. We investigated whether a family of VP882-like phages might exist that detect and respond to DPO. We find that indeed, VP882-like phages reside in DPO-producing bacterial species isolated at different times and geographic locations, suggesting their wide circulation in the environment. This discovery strengthens the evidence for the generality of phage-bacterial inter-domain chemical communication.

  PublisherDOI

• Inhibitors of the PqsR Quorum-Sensing Receptor Reveal Differential Roles for PqsE and RhlI in Control of Phenazine Production

  ACS Chemical Biology · 2025-05-14 · 3 citations

  articleOpen accessSenior authorCorresponding

  Pseudomonas aeruginosa is a leading cause of hospital-acquired infections and it is resistant to many current antibiotic therapies, making development of new antimicrobial treatments imperative. The cell-to-cell communication process called quorum sensing controls P. aeruginosa pathogenicity. Quorum sensing relies on the production, release, and group-wide detection of extracellular signal molecules called autoinducers. Quorum sensing enables bacteria to synchronize group behaviors. P. aeruginosa possesses multiple quorum-sensing systems that control overlapping regulons, including some required for virulence and biofilm formation. Interventions that target P. aeruginosa quorum-sensing receptors are considered a fruitful avenue to pursue for new therapeutic advances. Here, we developed a P. aeruginosa strain that carries a bioluminescent reporter fused to a target promoter that is controlled by two P. aeruginosa quorum-sensing receptors. The receptors are PqsR, which binds and responds to the autoinducer called PQS (2-heptyl-3-hydroxy-4(1H)-quinolone) and RhlR, which binds and responds to the autoinducer called C4-HSL (C4-homoserine lactone). We used this reporter strain to screen >100,000 compounds with the aim of identifying inhibitors of either or both the PqsR and RhlR quorum-sensing receptors. We report results for 30 PqsR inhibitors from this screen. All of the identified compounds inhibit PqsR with IC50 values in the nanomolar to low micromolar range and they are readily docked into the autoinducer binding site of the PqsR crystal structure, suggesting they function competitively. The majority of hits identified are not structurally related to previously reported PqsR inhibitors. Recently, RhlR was shown to rely on the accessory protein PqsE for full function. Specifically, RhlR controls different subsets of genes depending on whether or not it is bound to PqsE, however, the consequences of differential regulation on the quorum-sensing output response have not been defined. PqsR regulates pqsE. That feature of the system enabled us to exploit our new set of PqsR inhibitors to show that RhlR requires PqsE to activate the biosynthetic genes for pyocyanin, a key P. aeruginosa virulence factor, while C4-HSL is dispensable. These results highlight the promise of inhibition of PqsR as a possible P. aeruginosa therapeutic to suppress production of factors under RhlR-PqsE control.

  PublisherDOI

Recent grants

• Intra- and Inter- Species Communication in Bacteria

  NIH · $3.4M · 2020–2025

• Intercellular Signaling in Vibrio Harveyi

  NSF · $450k · 2004–2008

• NIH Grant R01GM065859

  NIH · $4.2M · 2016

• Predoctoral Training in Genetics and Molecular Biology

  NIH · $31.9M · 1977–2023

• NIH Grant R13GM072433

  NIH · $18k · 2005

Frequent coauthors

• Ned S. Wingreen

  Princeton University

  91 shared

• Howard A. Stone

  54 shared

• Justin E. Silpe

  52 shared

• Andrew A. Bridges

  Institute for Wildlife Studies

  51 shared

• M. Silverman

  40 shared

• Chenyi Fei

  40 shared

• Carey D. Nadell

  Dartmouth College

  39 shared

• Wai‐Leung Ng

  Tufts University

  37 shared

Education

• Ph.D.

  Johns Hopkins University

  1990

• B.S.

  University of California Davis

  1984

Awards & honors

• National Medal of Science (2024)
• Gairdner International Award (2023)
• Princess of Asturias Award for Technical and Scientific Rese…
• Microbiology Society Prize Medal (2022)
• Wolf Prize in Chemistry (2022)