Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Biofilms01:29

Biofilms

Biofilms are complex communities of microorganisms encased in a self-produced extracellular polysaccharide matrix attached to surfaces. These microbial consortia can include single or multiple species, providing enhanced survival benefits by forming organized, multilayered structures.The formation of biofilms occurs through four key stages: attachment, colonization, development, and dispersal.During attachment, free-swimming planktonic cells adhere to a surface, often facilitated by...
Genomic DNA in Prokaryotes00:46

Genomic DNA in Prokaryotes

The genome of most prokaryotic organisms consists of double-stranded DNA organized into one circular chromosome in a region of cytoplasm called the nucleoid. The chromosome is tightly wound, or supercoiled, for efficient storage. Prokaryotes also contain other circular pieces of DNA called plasmids. These plasmids are smaller than the chromosome and often carry genes that confer adaptive functions, such as antibiotic resistance.
Genomic Diversity in Bacteria
Although bacterial genomes are much...
Plasmids01:28

Plasmids

Plasmids are extrachromosomal DNA molecules found in bacteria, archaea, and some eukaryotic microbes like yeast. These small, circular DNA structures typically contain fewer than 30 genes, although some may exist linearly. Plasmids vary in their number within a cell, known as copy number. Single-copy plasmids are present in one copy per cell and multi-copy plasmids are present in multiple copies, reaching over 100 copies per cell.Plasmids usually replicate independently of the chromosomal DNA...
DNA Bacteriophages01:26

DNA Bacteriophages

Bacteriophages, or phages, are viruses that specifically infect bacteria, utilizing their genetic material to hijack host cellular machinery for replication. DNA bacteriophages employ single-stranded DNA (ssDNA) or double-stranded DNA (dsDNA) genomes. These phages exhibit diverse replication strategies and host interactions, influencing their ecological roles and applications in biotechnology and medicine.ssDNA BacteriophagesssDNA phages, with their small genomes, utilize unique strategies to...
Genomic DNA in Eukaryotes00:58

Genomic DNA in Eukaryotes

Eukaryotes have large genomes compared to prokaryotes. To fit their genomes into a cell, eukaryotic DNA is packaged extraordinarily tightly inside the nucleus. To achieve this, DNA is tightly wound around proteins called histones, which are packaged into nucleosomes that are joined by linker DNA and coil into chromatin fibers. Additional fibrous proteins further compact the chromatin, which is recognizable as chromosomes during certain phases of cell division.
Prokaryotic Cells01:28

Prokaryotic Cells

Prokaryotes are small unicellular organisms that include the domains — Archaea and Bacteria. Bacteria include many common microorganisms, such as Salmonella and E. coli, while the Archaea include extremophiles that live in harsh environments, such as volcanic springs.
Like eukaryotic cells, all prokaryotic cells are surrounded by a plasma membrane, have genetic material in the form of single, circular DNA, a cytoplasm that fills the interior of the cell, and ribosomes that synthesize proteins.

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Monoclonal Antibodies and Derivatives: Therapeutic Tools for Cancer.

Oncology research·2026
Same author

Correction: A multi-organ-on-chip to recapitulate the infiltration and the cytotoxic activity of circulating NK cells in 3D matrix-based tumor model.

Frontiers in bioengineering and biotechnology·2026
Same author

Smart Healing for Wound Repair: Emerging Multifunctional Strategies in Personalized Regenerative Medicine and Their Relevance to Orthopedics.

Antibiotics (Basel, Switzerland)·2026
Same author

Editorial: Cytokines, and biomarkers involved in the immunomodulation of pediatric cancers.

Frontiers in immunology·2025
Same author

Inflaming and Immune-Resolving: The Ambivalent Role of Eosinophils in Osteoarthritis.

International journal of molecular sciences·2025
Same author

Developing a 3D Model Culture of an EBV+/CD30+ B-Anaplastic Large Cell Lymphoma Cell Line to Assay Brentuximab Vedotin Treatment.

Antibodies (Basel, Switzerland)·2025

Related Experiment Video

Updated: May 27, 2026

Bile Salt-induced Biofilm Formation in Enteric Pathogens: Techniques for Identification and Quantification
10:05

Bile Salt-induced Biofilm Formation in Enteric Pathogens: Techniques for Identification and Quantification

Published on: May 6, 2018

Extracellular DNA in biofilms.

Lucio Montanaro1, Alessandro Poggi, Livia Visai

  • 1Research Unit on Implant Infections, Rizzoli Orthopaedic Institute, Bologna, Italy.

The International Journal of Artificial Organs
|November 19, 2011
PubMed
Summary
This summary is machine-generated.

Extracellular DNA (eDNA) is a key biofilm component released via bacterial autolysis. This DNA plays roles in biofilm structure, gene transfer, and immune recognition.

More Related Videos

Concurrent Quantification of Cellular and Extracellular Components of Biofilms
10:18

Concurrent Quantification of Cellular and Extracellular Components of Biofilms

Published on: December 10, 2013

Methodologies for Studying B. subtilis Biofilms as a Model for Characterizing Small Molecule Biofilm Inhibitors
10:17

Methodologies for Studying B. subtilis Biofilms as a Model for Characterizing Small Molecule Biofilm Inhibitors

Published on: October 9, 2016

Related Experiment Videos

Last Updated: May 27, 2026

Bile Salt-induced Biofilm Formation in Enteric Pathogens: Techniques for Identification and Quantification
10:05

Bile Salt-induced Biofilm Formation in Enteric Pathogens: Techniques for Identification and Quantification

Published on: May 6, 2018

Concurrent Quantification of Cellular and Extracellular Components of Biofilms
10:18

Concurrent Quantification of Cellular and Extracellular Components of Biofilms

Published on: December 10, 2013

Methodologies for Studying B. subtilis Biofilms as a Model for Characterizing Small Molecule Biofilm Inhibitors
10:17

Methodologies for Studying B. subtilis Biofilms as a Model for Characterizing Small Molecule Biofilm Inhibitors

Published on: October 9, 2016

Area of Science:

  • Microbiology
  • Molecular Biology
  • Immunology

Background:

  • Extracellular DNA (eDNA) is a recently identified, crucial component of bacterial biofilms.
  • eDNA has been observed in various bacterial species, including Pseudomonas aeruginosa, Streptococcus spp., Enterococcus faecalis, and staphylococci.

Purpose of the Study:

  • To investigate the mechanisms of eDNA release in different bacterial species.
  • To elucidate the role of eDNA in biofilm structure and stability.
  • To understand the implications of eDNA in bacterial gene transfer and host immune response.

Main Methods:

  • Analysis of bacterial autolysis mechanisms.
  • Observation of eDNA localization within biofilms.
  • Assessment of biofilm stability using DNase I treatment.
  • Investigation of eDNA's role in horizontal gene transfer.
  • Examination of eDNA recognition by the innate immune system via Toll-like receptors (TLRs).

Main Results:

  • eDNA is released through distinct autolysis mechanisms: quorum sensing-controlled lysis (P. aeruginosa), fratricide (E. faecalis), and programmed cell death (Staphylococcus aureus).
  • Specific enzymes like murein hydrolase and AtlE mediate autolysis in S. aureus and S. epidermidis, respectively.
  • eDNA is essential for biofilm structural integrity, particularly in P. aeruginosa and S. aureus, as demonstrated by DNase I sensitivity.
  • eDNA facilitates horizontal gene transfer and is recognized by the innate immune system through TLRs.

Conclusions:

  • Bacterial eDNA is a versatile molecule with significant roles in biofilm formation, genetic exchange, and host-pathogen interactions.
  • Understanding eDNA's function provides insights into biofilm dynamics and potential therapeutic targets.