About

Daniel E. Kadouri is an Associate Professor at Rutgers School of Dental Medicine, within the Department of Oral Biology. His research focuses on the interaction of biofilms and predatory prokaryotes, particularly bacteria from the genera Bdellovibrio and Micavibrio, with the aim of reducing biofilms in medical and industrial settings. His work involves understanding predator-prey interactions, the biology of these predatory bacteria, and their potential as biological control agents against drug-resistant bacteria and biofilms associated with infections. Kadouri's research also includes isolating novel antimicrobial and biofilm-degrading compounds from bacteria and biofilms, as well as exploring the use of microbial-derived compounds for postoperative pain relief. His educational background includes a BS in Biology and Agriculture, an MS in Virology, and a PhD from Hebrew University in Jerusalem.

Research topics

• Biology
• Ecology
• Microbiology
• Genetics
• Internal medicine
• Zoology

Selected publications

• Predator–prey dynamics of <i>Vibrio cholerae</i> on chitin suggest an alternative mode of biofilm formation in marine snow conditions

  The ISME Journal · 2026-01-01

  articleOpen access

  Vibrio cholerae is a ubiquitous marine bacterium that solubilizes and consumes chitin in the marine water column. In both the marine environment and the intestinal tract, V. cholerae forms biofilms: how do the diverse surfaces that V. cholerae encounters influence its biofilm formation and, in turn, shape its ecological interactions with other microbes? Here, we use the interaction between the predator Bdellovibrio bacteriovorus and V. cholerae as a model to explore how the environmental chitin substrate alters V. cholerae biofilm formation and predator-prey dynamics. We find that glass-bound biofilm growth provides strong protection for V. cholerae against predation while also allowing a population of predatory B. bacteriovorus to remain in place among prey cells. In contrast, chitin-bound biofilm structure offers less protection against B. bacteriovorus predation and does not maintain as stable a population of B. bacteriovorus. Using percolation and population dynamics models, we predict that these changes in predator-prey dynamics can be explained largely by alterations in V. cholerae biofilm architecture between the two conditions, which changes the fraction of prey available to B. bacteriovorus. Using targeted biofilm matrix gene deletions, we confirm this prediction by recapitulating key features of the chitin predator-prey interactions on glass surfaces. Following on this observation, we show that V. cholerae biofilms grown on chitin produce much less of the canonical biofilm matrix components and instead rely on other extracellular structures. Overall, our experiments detail how growth substrate can alter biofilm matrix composition and how these changes in biofilm architecture impact higher-order ecological interactions.

  PublisherDOI

• Using AlphaFold-Multimer to study novel protein-protein interactions of predation essential hypothetical proteins in Bdellovibrio

  Frontiers in Bioinformatics · 2025-04-14 · 6 citations

  articleOpen accessCorresponding

  Bdellovibrio bacteriovorus is the most studied member of a group of small motile Gram-negative bacteria called Bdellovibrio and Like Organisms (BALOs). B. bacteriovorus can prey on Gram-negative bacteria, including multi-drug resistant pathogens, and has been proposed as an alternative to antibiotics. Although the life cycle of B. bacteriovorus is well characterized, some molecular aspects of B. bacteriovorus -prey interaction are poorly understood. Hypothetical proteins with unestablished functions have been implicated in B. bacteriovorus predation by many studies. Our approach to characterize these proteins employing Alphafold has revealed novel interactions among attack phase-hypothetical proteins, which may be involved in less understood mechanisms of the Bdellovibrio attack phase. Here, we overlapped attack phase genes from B. bacteriovorus transcriptomic data sets and from transposon sequencing data sets to generate a set of proteins that are both expressed at the attack phase and are necessary for predation, which we termed Attack Phase Predation-Essential Proteins (AP-PEP). By applying Markov Cluster Algorithm and AlphaFold-Multimer to analyze the protein network and interaction partners of the AP-PEPs, we predicted high-confidence protein-protein interactions and two structurally similar but unique novel protein complexes formed among proteins of the Bd2209-Bd2212 and Bd2723-Bd2726 operons. Furthermore, we confirmed the interaction between hypothetical proteins Bd0075 and Bd0474 using the Bacteria Adenylate Cyclase Two-Hybrid system. In addition, we confirmed that the C-terminal domain of Bd0075, which contains Tetratricopeptide repeat motifs, participates principally in its interaction with Bd0474. This study revealed previously unknown cooperation among predation essential hypothetical proteins in the attack phase B. bacteriovorus and has paved the way for further work to understand molecular mechanisms of BALO predation processes.

  PublisherDOI

• Eying up predatory bacteria: living antimicrobials for ocular infections

  Current Opinion in Ophthalmology · 2025-12-01

  articleSenior author

  PURPOSE OF REVIEW: The growing threat of antibiotic-resistant pathogens, particularly in ocular infections like bacterial keratitis, necessitates alternative therapeutic strategies. This review evaluates the potential therapeutic role of predatory bacteria as novel live antimicrobials, offering a timely exploration of their potential in overcoming resistance mechanisms such as biofilm formation and persister cell development. RECENT FINDINGS: Predatory bacteria, including Bdellovibrio bacterovorus and Micavibrio aerguinosavorus selectively target Gram-negative bacteria, including Pseudomonas aeruginosa , while sparing Gram-positive ocular surface. They exhibit rapid bactericidal activity and efficacy against biofilms, persister cells, and antibiotic-resistant pathogens, but induce little inflammation. Advances in storage and delivery methods, such as lyophilization, cryomicroneedles, and thermoresponsive hydrogels, have potential to increase their therapeutic feasibility. However, in-vivo efficacy remains variable and their narrow spectrum limits effectiveness against Gram-positive pathogens. SUMMARY: Predatory bacteria present a promising alternative to traditional antibiotics in ocular therapeutics, particularly for drug-resistant infections. Integration of predatory bacteria with bacteriophages or conventional antibiotics may further optimize their potential. Continued translational research is essential to address current limitation and to validate their safety and efficacy for human or veterinary applications.

  PublisherDOI

• <i>Vibrio cholerae</i> interaction with predatory bacteria on chitin suggests an alternative mode of biofilm formation in marine snow conditions

  bioRxiv (Cold Spring Harbor Laboratory) · 2025-10-31

  preprintOpen access

  Abstract Vibrio cholerae is a ubiquitous marine microbe that solubilizes and consumes chitin in the marine water column. In both the marine environment and the intestinal track, V. cholerae forms biofilms; a key question regarding the lifestyle of V. cholerae is how do the diverse substrates that it encounters influence its biofilm formation and, in turn, shape its ecological interactions. Here, we use the predator-prey interaction between Bdellovibrio bacteriovorus and V. cholerae as a model to explore how the environmental chitin substrate alters V. cholerae biofilm formation and predator-prey interactions. We find that glass-bound biofilms provide strong protection for V. cholerae against predation while also allowing a population of predatory B. bacteriovorus to remain in place. In contrast, chitin-bound biofilms offer less protection against B. bacteriovorus predation and do not maintain a stable population of B. bacteriovorus . Using percolation and population dynamics models, we predict that these changes in predator-prey dynamics can be mostly explained by alterations in biofilm architecture between the two conditions, which changes the fraction of prey available to B. bacteriovorus . Performing targeted biofilm matrix deletions, we confirm this prediction by recapitulating key features of the chitin predator-prey interactions on glass surfaces. Following on this observation, we show that V. cholerae biofilms grown on chitin produce much less of the canonical biofilm matrix components and instead rely on other extracellular structures. Overall, our experiments detail how growth substrate can alter biofilm matrix composition and how these changes in biofilm architecture and cellular arrangement can impact higher-order ecological interactions.

  PublisherDOI

• Predatory bacteria prevent the proliferation of intraocular Serratia marcescens and fluoroquinolone-resistant Pseudomonas aeruginosa

  Microbiology · 2024-02-15 · 8 citations

  articleOpen access

  Endogenous endophthalmitis caused by Gram-negative bacteria is an intra-ocular infection that can rapidly progress to irreversible loss of vision. While most endophthalmitis isolates are susceptible to antibiotic therapy, the emergence of resistant bacteria necessitates alternative approaches to combat intraocular bacterial proliferation. In this study the ability of predatory bacteria to limit intraocular growth of Pseudomonas aeruginosa , Serratia marcescens , and Staphylococcus aureus was evaluated in a New Zealand white rabbit endophthalmitis prevention model. Predatory bacteria Bdellovibrio bacteriovorus and Micavibrio aeruginosavorus were able to reduce proliferation of keratitis isolates of P. aeruginosa and to a lesser extent S. marcescens . However, it was not able to significantly reduce the number of intraocular S. aureus, which is not a productive prey for these predatory bacteria, suggesting that the inhibitory effect on P. aeruginosa and S. marcescens requires active predation rather than an antimicrobial immune response. Similarly, UV-inactivated B. bacteriovorus were unable to prevent proliferation of P. aeruginosa . Together, these data indicate in vivo inhibition of Gram-negative bacteria proliferation within the intra-ocular environment by predatory bacteria.

  PublisherDOI

• <i>Bdellovibrio bacteriovorus</i> Therapy, an Emerging Alternative to Antibiotics

  Letters in Drug Design & Discovery · 2023-09-13 · 2 citations

  articleCorresponding
  PublisherDOI

• Predatory bacteria can reduce Pseudomonas aeruginosa induced corneal perforation and proliferation in a rabbit keratitis model

  The Ocular Surface · 2023-04-01 · 15 citations

  articleOpen access
  PublisherOA PDFDOI

• Breakdown of clonal cooperative architecture in multispecies biofilms and the spatial ecology of predation

  Proceedings of the National Academy of Sciences · 2023 · 36 citations

  • Biology
  • Microbiology
  • Ecology

  cells at the start of biofilm growth. When this occurs, the two species become intermixed, and the resulting disordered cell groups do not block predator entry. Because biofilm cell group structure depends on initial cell distributions at the start of prey biofilm growth, the surface colonization dynamics have a dramatic impact on the eventual multispecies biofilm architecture, which in turn determines to what extent both species survive exposure to

  PublisherOA PDFDOI

• Intra-ocular Predation of Fluoroquinolone-Resistant <i>Pseudomonas aeruginosa</i> and <i>Serratia marcescens</i> by Predatory Bacteria

  bioRxiv (Cold Spring Harbor Laboratory) · 2023-09-17

  preprintOpen access

  Abstract Endogenous endophthalmitis caused by Gram-negative bacteria is an intra-ocular infection that can rapidly progress to irreversible loss of vision. While most endophthalmitis isolates are susceptible to antibiotic therapy, the emergence of resistant bacteria necessitates alternative approaches to combat intraocular bacterial proliferation. In this study the ability of predatory bacteria to limit intraocular growth of Pseudomonas aeruginosa, Serratia marcescens , and Staphylococcus aureus was evaluated in a New Zealand White rabbit endophthalmitis prevention model. Predatory bacteria Bdellovibrio bacteriovorus and Micavibrio aeruginosavorus were able to reduce proliferation of keratitis isolates of P. aeruginosa and S. marcescens . However, it was not able to significantly reduce S. aureus , which is not a productive prey for these predatory bacteria, suggesting that the inhibitory effect on P. aeruginosa requires active predation rather than an antimicrobial immune response. Similarly, UV-inactivated B. bacteriovorus were unable to prevent proliferation of P. aeruginosa . Together, these data suggest in vivo predation of Gram-negative bacteria within the intra-ocular environment.

  PublisherOA PDFDOI

• Predatory Bacteria can Reduce <i>Pseudomonas aeruginosa</i> Induced Corneal Perforation and Proliferation in a Rabbit Keratitis Model

  bioRxiv (Cold Spring Harbor Laboratory) · 2023-03-15

  preprintOpen access

  Abstract Purpose Pseudomonas aeruginosa keratitis is a severe ocular infection that can lead to perforation of the cornea. In this study we evaluated the role of bacterial quorum sensing in generating corneal perforation and bacterial proliferation and tested whether co-injection of the predatory bacteria Bdellovibrio bacteriovorus could alter the clinical outcome. P. aeruginosa with lasR mutations were observed among keratitis isolates from a study collecting samples from India, so an isogenic lasR mutant strain of P. aeruginosa was included. Methods Rabbit corneas were intracorneally infected with P. aeruginosa strain PA14 or an isogenic Δ lasR mutant and co-injected with PBS or B. bacteriovorus . After 24 h, eyes were evaluated for clinical signs of infection. Samples were analyzed by scanning electron microscopy, optical coherence tomography, sectioned for histology, and corneas were homogenized for CFU enumeration and for inflammatory cytokines. Results We observed that 54% of corneas infected by wild-type PA14 presented with a corneal perforation (n=24), whereas only 4% of PA14 infected corneas that were co-infected with B. bacteriovorus perforate (n=25). Wild-type P. aeruginosa proliferation was reduced 7-fold in the predatory bacteria treated eyes. The Δ lasR mutant was less able to proliferate compared to the wild-type, but was largely unaffected by B. bacteriovorus . Conclusion These studies indicate a role for bacterial quorum sensing in the ability of P. aeruginosa to proliferate and cause perforation of the rabbit cornea. Additionally, this study suggests that predatory bacteria can reduce the virulence of P. aeruginosa in an ocular prophylaxis model.

  PublisherOA PDFDOI

Frequent coauthors

• Robert M. Q. Shanks

  University of Pittsburgh

  23 shared

• Nancy Connell

  Rutgers New Jersey Medical School

  16 shared

• Eric G. Romanowski

  University of Pittsburgh

  13 shared

• Shilpi Gupta

  12 shared

• Chi Tang

  9 shared

• Mennat Elsayed

  Rutgers, The State University of New Jersey

  9 shared

• Nicholas A. Stella

  University of Pittsburgh

  9 shared

• Édouard Jurkevitch

  Hebrew University of Jerusalem

  9 shared