Ligamenvirales

Ligamenvirales is an order of viruses that was established by the International Committee on Taxonomy of Viruses (ICTV) in 2019. The order includes viruses that infect archaea, a domain of single-celled microorganisms. These viruses have a unique morphology, characterized by a lemon-shaped virion, which is a complete virus particle, consisting of an RNA or DNA core with a protein coat.

Taxonomy

The order Ligamenvirales includes the following families:

• Ligamenviridae
• Turriviridae

These families are distinguished by their host range, genome organization, and virion structure.

Structure and Genome

Viruses in the order Ligamenvirales have a unique lemon-shaped morphology. The virion is approximately 100 nm in length and 60 nm in diameter. The genome of these viruses is linear, double-stranded DNA, which is unusual among archaeal viruses. The genome size ranges from 16 to 20 kilobases.

Replication

The replication cycle of Ligamenvirales viruses begins with the attachment of the virus to the host cell. The viral DNA is then injected into the host cell, where it is replicated and transcribed. The newly synthesized viral proteins and DNA are assembled into new virions, which are released from the host cell by lysis.

Ecology

Ligamenvirales viruses are found in extreme environments, such as hot springs and salt lakes, where their archaeal hosts live. They play a significant role in the ecology of these environments by influencing the diversity and evolution of archaeal communities.

See Also

• Virus classification
• Archaea
• Virion
• International Committee on Taxonomy of Viruses