Related Experiment Video
Updated: Mar 7, 2026
07:58
Laboratory Techniques Used to Maintain and Differentiate Biotypes of Vibrio cholerae Clinical and Environmental Isolates
Published on: May 30, 2017
11.6K
Replication of Vibrio cholerae classical CTX phage.
Eun Jin Kim1,2, Hyun Jin Yu1,2, Je Hee Lee3
1Department of Pharmacy, College of Pharmacy, Hanyang University, Ansan 15588, Republic of Korea.
Summary
This study demonstrates the replication and transmission of cholera toxin phages (CTX phages) in Vibrio cholerae strains. These findings provide experimental evidence for the genetic mechanisms driving the evolution of V. cholerae.
Area of Science:
- Microbiology
- Genetics
- Molecular Biology
Background:
- Toxigenic Vibrio cholerae O1 strains (classical and El Tor biotypes) arise from CTX phage lysogenization.
- Replication and transmission of El Tor-specific CTX phage (CTX-1) explain El Tor strain evolution.
- Classical biotype CTX phage (CTX-cla) was thought to be defective, but atypical strains suggest replication and transmission.
Purpose of the Study:
- To demonstrate laboratory replication of CTX-cla and CTX-2 phages.
- To show transduction of El Tor strains by various CTX phages.
- To investigate the genetic mechanisms of Vibrio cholerae evolution.
Main Methods:
- Established a plasmid-based CTX phage replication system.
- Demonstrated replication of CTX-1, CTX-cla, CTX-2, and CTX-O139.
- Showed replication of CTX-2 from tandem repeats in Wave 2 El Tor strains.
- Induced in vitro transduction of El Tor strains via a toxT mutation.
Main Results:
- Confirmed replication of CTX-cla and CTX-2 phages.
- Successfully transduced El Tor strains with multiple CTX phages in vitro.
- Identified a toxT point mutation that enhances cholera toxin expression in El Tor strains.
- Provided experimental evidence for CTX phage replication and transmission mechanisms.
Conclusions:
- The study provides experimental evidence for the replication and transmission of classical and El Tor biotype CTX phages.
- A plasmid-based system supports replication of diverse CTX phages, including CTX-cla and CTX-2.
- A toxT mutation facilitates CTX phage transduction and increases cholera toxin expression in El Tor strains, elucidating V. cholerae evolution.
Related Concept Videos
01:16Viral Replication: Lysogenic Cycle
2.1K
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...
2.1K
01:20Viral Replication: Lytic Cycle
2.1K
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...
2.1K
00:43Lysogenic Cycle of Bacteriophages
68.6K
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...
68.6K
01:26DNA Bacteriophages
1.2K
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...
1.2K
01:30Lytic Cycle of Bacteriophages
78.9K
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...
78.9K
01:29Bacterial Phylum Chlamydiae
678
The phylum Chlamydiae or Chlamydiota is composed of a single order, Chlamydiales. This phylum consists entirely of obligate intracellular parasites that infect eukaryotic hosts. While human pathogens within this group have been studied extensively, the phylum encompasses many species capable of interacting with various eukaryotic organisms. Members of Chlamydiae are typically small cocci, approximately 0.5 μm in diameter, and exhibit a distinctive developmental cycle. As is characteristic...
678