Podoviruses
Podoviridae
Podoviridae is a family of bacteriophages characterized by an icosahedral capsid and a very short, non-contractile tail. They infect specific bacteria and archaea by injecting their double-stranded DNA genome through the tail apparatus into the host. These viruses are globally distributed in aquatic and terrestrial habitats and play a central role in regulating bacterial populations.
Details
Identification
Icosahedral capsid (approx. 60 nm diameter), very short tail (approx. 10 nm), double-stranded DNA, non-enveloped.
Diet
As obligate parasites, they utilize the metabolic machinery of their bacterial hosts to produce new viral particles.
Hunting strategy
Adsorption to specific surface receptors of host bacteria and subsequent injection of the genome.
Ecology
Ecological role
Key player in the 'viral shunt'; they lyse bacteria, thereby releasing organic carbon and nutrients back into the microbial food web.
Natural predators
Degradation by UV radiation, enzymes in the water, and passive ingestion by filtering microorganisms.
Competitor species
Other bacteriophage families such as Myoviridae and Siphoviridae that infect the same host bacteria.
Ecosystem service
Regulation of bacterial blooms and promotion of nutrient cycling in aquatic ecosystems.
Scientific profile
Profile
Habitat
Ubiquitously distributed in aquatic systems (marine and freshwater), soils, sewage, and the gastrointestinal tract of humans and animals.
Ecological role
Essential role in the 'viral shunt': Lysis of bacteria releases organic matter (DOC) back into the microbial loop instead of passing it to higher trophic levels. Also promotes horizontal gene transfer (transduction).