Related Experiment Video
Updated: Jun 24, 2026
09:40
Phage Phenomics: Physiological Approaches to Characterize Novel Viral Proteins
Published on: June 11, 2015
[Virus and prophages in aquatic ecosystems]
Télesphore Sime-Ngando1, Jonathan Colombet
1Universite Blaise-Pascal, 63177 Aubiere, France. telesphore.sime-ngando@univ-bpclermont.fr
Canadian Journal of Microbiology
|March 20, 2009
Summary
Aquatic viruses, abundant and diverse, significantly impact microbial communities and biogeochemical cycles through lysis and gene transfer. Future research priorities include cyanophages and phytoplanktonic phages in freshwater lakes.
Area of Science:
- Aquatic microbial ecology
- Viral ecology
- Environmental microbiology
Context:
- Viruses are the most abundant and diverse biological entities in aquatic ecosystems.
- Aquatic viruses, primarily phages, influence microbial mortality, community structure, and diversity.
- Phages play key roles in biogeochemical cycles via lysis products and horizontal gene transfers.
Purpose:
- To review the structure and functional roles of natural viruses in aquatic food webs.
- To summarize the impact of viruses on microbial ecology and biogeochemical cycles.
- To identify future research directions in viral ecology.
Summary:
- This review synthesizes data on viral structure (diversity, abundance, biomass) and functions (bacteriolysis, lysogeny, gene transfer) in aquatic microbial ecosystems.
- Aquatic viruses, predominantly phages, significantly affect host community structure and diversification.
- Viruses contribute to biogeochemical catalysis and possess genes for functions like photosynthesis, impacting evolutionary biology.
Impact:
- Viral ecology provides new insights into environmental sciences and the evolution of cellular organisms.
- The discovery of giant viruses and viriophages challenges definitions of life and fuels debate on viral status.
- Prioritizing research on cyanophages and phytoplanktonic phages in freshwater ecosystems is crucial for advancing aquatic ecology.
Related Concept Videos
01:23Bacteriophages 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...
01:29Viruses of Archaea
Archaeal viruses play a crucial role in the ecosystems of extremophilic archaea, particularly those belonging to the phyla Euryarchaeota and Crenarchaeota. By shaping host evolution and facilitating gene transfer, these viruses influence microbial communities and contribute to genetic diversity in extreme environments. The archaea they infect thrive in acidic hot springs and hydrothermal vents characterized by high temperatures and low pH. Archaeal viruses exhibit remarkable structural...
01:16Viral 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...
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...
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...
01:26DNA 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...