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

Lytic Cycle of Bacteriophages01:30

Lytic 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...
Lysogenic Cycle of Bacteriophages00:43

Lysogenic 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...
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...
Viral Replication: Lytic Cycle01:20

Viral 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...
Bacteriophages of the Human Virome01:23

Bacteriophages 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...
Viral Replication: Lysogenic Cycle01:16

Viral Replication: Lysogenic Cycle

The lysogenic cycle is a crucial viral replication strategy that allows bacteriophages to persist within host cells without immediately destroying them. This process is primarily observed in temperate phages, such as bacteriophage lambda (λ), which infects Escherichia coli. The cycle allows the viral genome to persist across bacterial generations while keeping host cells viable.Integration of the Viral GenomeUpon infection, bacteriophage lambda attaches to the bacterial surface and injects its...

You might also read

Related Articles

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

Sort by
Same author

Further observations on the mechanism of phage action.

The Journal of general physiology·2010
Same author

Effect of penicillin on the reaction between phage and staphylococci.

Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine (New York, N.Y.)·2010
Same author

THE ELECTRICAL CHARGE OF BACTERIOPHAGE.

The Journal of experimental medicine·2009
Same author

THE PREPARATION OF RELATIVELY PURE BACTERIOPHAGE.

The Journal of general physiology·2009
Same author

THE PREPARATION OF A GRADED SERIES OF ULTRAFILTERS AND MEASUREMENT OF THEIR PORE SIZES.

The Journal of general physiology·2009
Same author

A METHOD FOR THE QUANTITATIVE ESTIMATION OF BACTERIA IN SUSPENSIONS.

The Journal of general physiology·2009

Related Experiment Video

Updated: Jun 19, 2026

Following Cell-fate in E. coli After Infection by Phage Lambda
06:10

Following Cell-fate in E. coli After Infection by Phage Lambda

Published on: October 14, 2011

INTRACELLULAR PHAGE PRECURSOR.

A P Krueger1, E J Scribner

  • 1Department of Bacteriology, University of California, Berkeley.

The Journal of General Physiology
|October 30, 2009
PubMed
Summary
This summary is machine-generated.

Activated staphylococci, when added to phage solutions, significantly increase phage numbers. This phage-augmenting property, linked to a protein precursor, is heat-sensitive and requires bacterial growth in oxygen for activation.

More Related Videos

Synthesis of Infectious Bacteriophages in an E. coli-based Cell-free Expression System
11:33

Synthesis of Infectious Bacteriophages in an E. coli-based Cell-free Expression System

Published on: August 17, 2017

Phage-Mediated Genetic Manipulation of the Lyme Disease Spirochete Borrelia burgdorferi
09:01

Phage-Mediated Genetic Manipulation of the Lyme Disease Spirochete Borrelia burgdorferi

Published on: September 28, 2022

Related Experiment Videos

Last Updated: Jun 19, 2026

Following Cell-fate in E. coli After Infection by Phage Lambda
06:10

Following Cell-fate in E. coli After Infection by Phage Lambda

Published on: October 14, 2011

Synthesis of Infectious Bacteriophages in an E. coli-based Cell-free Expression System
11:33

Synthesis of Infectious Bacteriophages in an E. coli-based Cell-free Expression System

Published on: August 17, 2017

Phage-Mediated Genetic Manipulation of the Lyme Disease Spirochete Borrelia burgdorferi
09:01

Phage-Mediated Genetic Manipulation of the Lyme Disease Spirochete Borrelia burgdorferi

Published on: September 28, 2022

Area of Science:

  • Microbiology
  • Bacteriology
  • Virology

Background:

  • Staphylococci activation by oxygen and cold storage.
  • Phage-augmenting properties of activated staphylococci.

Purpose of the Study:

  • Investigate the mechanism of phage production enhancement by activated staphylococci.
  • Characterize the reaction between activated staphylococci and bacteriophages.
  • Explore the nature of the phage precursor.

Main Methods:

  • Activation of staphylococci through growth in oxygen and subsequent cold storage.
  • Assaying phage augmentation in phage-containing solutions with activated staphylococci.
  • Heat inactivation studies to determine thermal increment.
  • Inhibition studies using antisera.

Main Results:

  • Activated staphylococci significantly increase phage concentration.
  • Activation requires aerobic growth; optimal pH is acidic but broad range tolerated.
  • Phage augmentation property is retained for 4-24 hours and is heat-labile.
  • Reaction is rapid (1-2 minutes) and independent of bacterial growth.
  • Antisera block the phage-augmenting effect.
  • Critical thermal increment suggests protein denaturation.

Conclusions:

  • The reaction aligns with the precursor theory, suggesting a protein precursor.
  • The process may involve protein hydrolysis or phage-catalyzed synthesis.
  • Activated staphylococci play a crucial role in bacteriophage replication dynamics.