Related Experiment Video
Updated: Jul 3, 2026
08:46
T4 Bacteriophage and E. coli Interaction in the Murine Intestine: A Prototypical Model for Studying Host-Bacteriophage Dynamics In Vivo
Published on: January 26, 2024
Partial characterization of Enterococcus faecalis bacteriophage F4
K Nigutová1, I Styriak, P Javorský
1Institute of Animal Physiology, Slovak Academy of Sciences, Kosice, Slovakia. nigutova@saske.sk
Folia Microbiologica
|July 29, 2008
Summary
Researchers characterized the Enterococcus faecalis F4 bacteriophage, identifying three essential genes. These genes are rare in natural enterococcal populations, indicating a low frequency of F4 lysogens.
Area of Science:
- Microbiology
- Virology
- Molecular Biology
Background:
- Enterococcus faecalis bacteriophages are viruses that infect this common bacterium.
- The F4 bacteriophage of E. faecalis is a large virus with double-stranded DNA.
Purpose of the Study:
- To characterize the essential genes of the E. faecalis F4 bacteriophage.
- To determine the prevalence of these phage genes in natural enterococcal isolates.
Main Methods:
- DNA sequencing of random fragments from the F4 bacteriophage.
- Polymerase Chain Reaction (PCR) to detect specific phage genes in enterococcal isolates.
Main Results:
- Three essential genes (DNA polymerase, replicative DNA helicase, minor capsid protein) were identified in the F4 bacteriophage.
- These genes showed limited homology to known phage genes.
- Only 2 out of 40 tested E. faecalis isolates contained all three genes; 3 contained at least one gene.
Conclusions:
- The characterized genes are essential for F4 bacteriophage function.
- The low frequency of these genes in natural isolates suggests that F4 lysogens are uncommon in enterococcal populations.
Related Concept Videos
01:26DNA 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...
01:20Viral Replication: Lytic Cycle
Bacteriophages, or phages, are viruses that specifically infect bacteria. Among them, T-even bacteriophages, such as T4, exhibit a well-characterized lytic replication cycle in Escherichia coli (E. coli). This process ensures the rapid proliferation of the virus while ultimately leading to the destruction of the bacterial host.Attachment and DNA InjectionThe infection process begins with the recognition and binding of the T4 phage to the E. coli cell surface. Tail fibers of the phage...
01:30Lytic Cycle of Bacteriophages
Bacteriophages, also known as phages, are specialized viruses that infect bacteria. A key characteristic of phages is their distinctive “head-tail” morphology. A phage begins the infection process (i.e., lytic cycle) by attaching to the outside of a bacterial cell. Attachment is accomplished via proteins in the phage tail that bind to specific receptor proteins on the outer surface of the bacterium. The tail injects the phage’s DNA genome into the bacterial cytoplasm. In the lytic replication...
01:23Bacteriophages of the Human Virome
Bacteriophages are found throughout the human body. They may even outnumber eukaryotic viruses, forming an important and dynamic component of the human virome. Indeed, phages represent the most abundant viral entities, with densities in the gut reaching up to 10⁹ particles per gram of fecal matter, and many belonging to orders such as Caudovirales and Microviridae, while a substantial proportion remains unclassified as viral “dark matter.”Lysogeny and Genetic ExchangeIn the gut, bacteriophages...
00:43Lysogenic Cycle of Bacteriophages
In contrast to the lytic cycle, phages infecting bacteria via the lysogenic cycle do not immediately kill their host cell. Instead, they combine their genome with the host genome, allowing the bacteria to replicate the phage DNA along with the bacterial genome. The incorporated copy of the phage genome is called the prophage. Some prophages can re-activate and enter the lytic cycle. This often occurs in response to a perturbation, such as DNA damage, but can also transpire in the absence of...
01:19Conjugation
Conjugation is a form of horizontal gene transfer that primarily occurs in bacteria and some archaea, promoting genetic diversity and adaptation. Bacteria can acquire resistance genes through conjugative plasmids, allowing them to survive antibiotic treatments that would otherwise be lethal. This process involves direct contact between cells through specialized structures such as the sex pilus and is mediated by conjugative plasmids, including the F (fertility) factor.Conjugation requires...