Related Experiment Video
Updated: Jun 19, 2026
07:19
Bacteriophage Removal from Infected Salmonella Cultures
Published on: June 28, 2024
ON SPECIFIC INHIBITION OF BACTERIOPHAGE ACTION BY BACTERIAL EXTRACTS.
1Laboratory of Pathology and Medical Bacteriology, University of Wisconsin, Madison.
The Journal of Experimental Medicine
|October 30, 2009
Summary
Bacterial products can specifically inhibit bacteriophages, with reactions occurring faster at 37°C. This suggests soluble carbohydrates are key to the specific interactions between bacteria and phages.
Area of Science:
- Microbiology
- Virology
- Immunochemistry
Background:
- Bacteriophages (phages) are viruses that infect bacteria.
- Understanding phage-bacterial interactions is crucial for various applications, including phage therapy.
- Soluble bacterial products and their role in phage inhibition are not fully elucidated.
Purpose of the Study:
- To demonstrate specific inhibition of bacteriophage activity by soluble bacterial products.
- To investigate the temperature dependence of this inhibitory reaction.
- To explore the chemical basis of the specificity in phage-bacterial interactions.
Main Methods:
- Incubation of bacteriophage preparations with soluble extracts from bacterial cultures.
- Comparative analysis of inhibition rates at different temperatures (37°C vs. 4°C).
- Investigation of the role of specific soluble carbohydrates in mediating the observed specificity.
Main Results:
- Specific inhibition of bacteriophage infectivity was observed using soluble bacterial products.
- The inhibitory reaction proceeded significantly faster at 37°C compared to 4°C.
- The specificity of the inhibition was strongly correlated with the presence of particular soluble carbohydrates.
Conclusions:
- Soluble bacterial products possess specific bacteriophage-inhibitory properties.
- Temperature influences the rate of phage inhibition by bacterial extracts.
- Specific soluble carbohydrates are likely mediators of the specific interactions between bacteriophages and bacterial antigens.
Related Concept Videos
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...
01:28Biological Methods for Microbial Control
Biological agents offer an effective means of controlling microbial growth by leveraging natural processes like predation, competition, and the secretion of antimicrobial substances.Predatory bacteria such as Bdellovibrio species target and kill pathogens like Salmonella and E. coli. They are widely used in poultry farms to control infections. Myxococcus species help combat plant-pathogenic fungi. These naturally occurring predators serve as eco-friendly alternatives to chemical pesticides and...
01:28Regulation of Bacterial Virulence
Pathogenic bacteria employ a range of regulatory mechanisms to modulate the expression of virulence genes in response to environmental and host-derived signals. These mechanisms ensure that virulence factors are expressed only under favorable conditions, thereby optimizing infection and survival strategies.Mechanisms of Virulence RegulationKey regulatory strategies include:Two-Component Systems: These consist of a membrane-bound sensor kinase and a cytoplasmic response regulator. Environmental...
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...
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...