Related Experiment Video

Updated: Aug 23, 2026

Time-Lapse Epifluorescence Microscopy Imaging of Pseudomonas aeruginosa and Staphylococcus aureus Heterogeneous Phenotypes
07:44

Time-Lapse Epifluorescence Microscopy Imaging of Pseudomonas aeruginosa and Staphylococcus aureus Heterogeneous Phenotypes

Published on: February 14, 2025

Penetration of membrane-containing double-stranded-DNA bacteriophage PM2 into Pseudoalteromonas hosts

Hanna M Kivelä1, Rimantas Daugelavicius, Riina H Hankkio

  • 1Faculty of Biosciences and Institute of Biotechnology, University of Helsinki, Finland.

Journal of Bacteriology
|August 5, 2004
PubMed

Insights

Bacteriophage PM2 infection involves protein coat dissociation and viral membrane fusion with the host cell outer membrane. The P7 protein aids peptidoglycan penetration, differing from other dsDNA viruses like PRD1.

Area of Science:

  • Microbiology
  • Virology
  • Molecular Biology

Background:

  • Bacteriophage PM2, the sole member of the Corticoviridae family, possesses a unique icosahedral structure with a circular double-stranded DNA genome and an internal lipid membrane.
  • The mechanism of genome translocation into gram-negative marine Pseudoalteromonas hosts remains poorly understood.

Purpose of the Study:

  • To elucidate the entry mechanism of bacteriophage PM2 into its host cell.
  • To investigate the roles of viral components and host cell interactions during infection.

Main Methods:

  • Observational studies on viral binding and host cell interactions.
  • Analysis of membrane permeability changes using lipophilic molecules like gramicidin D.
  • Assessment of cytoplasmic membrane depolarization.
  • Comparative analysis with bacteriophage PRD1 entry.

Main Results:

  • Viral binding to cell surface receptors triggers protein coat dissociation.
  • Host outer membrane transiently becomes permeable, suggesting viral-host membrane fusion.
  • Integral membrane protein P7 exhibits muralytic activity, facilitating peptidoglycan penetration.
  • Virion entry induces limited cytoplasmic membrane depolarization.

Conclusions:

  • Bacteriophage PM2 employs a distinct entry mechanism involving membrane fusion and specific protein-mediated penetration.
  • This mechanism differs significantly from the tubular structure formation used by bacteriophage PRD1.

More Related Videos

Phage-Mediated Genetic Manipulation of the Lyme Disease Spirochete Borrelia burgdorferi09:01

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

Published on: September 28, 2022

Phage Phenomics: Physiological Approaches to Characterize Novel Viral Proteins09:40

Phage Phenomics: Physiological Approaches to Characterize Novel Viral Proteins

Published on: June 11, 2015

Related Concept Videos

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...
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...
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...