Virioniin

Virioniin is a term used in some virology writings to denote the complete infectious virus particle, commonly called a virion. In standard English usage, virion is the preferred term; virioniin may reflect linguistic, geographic, or historical usage rather than a distinct biological concept.

An individual virioniin consists of a genome—either DNA or RNA—enclosed by a protein shell called the capsid. Many virioniin also carry a lipid envelope derived from the host cell membrane, with embedded glycoproteins that mediate attachment and entry into new host cells. Structural forms vary: non-enveloped virions are often icosahedral or helical, while enveloped virions are typically more pleomorphic. Size ranges roughly from 20 to 300 nanometers.

Genomes can be single- or double-stranded, segmented or non-segmented, and may be positive- or negative-sense RNA or DNA. These properties influence replication strategies, gene expression, and interactions with host cells. After attachment to a susceptible cell, the virioniin enters by endocytosis or membrane fusion, releases its genome, and uses host or virally encoded enzymes to replicate and produce new virions, which are then assembled and released by lysis or budding.

Laboratory study of virioniin employs electron microscopy, genome sequencing, and quantitative assays such as plaque assays or qPCR to quantify particles and assess infectivity. Stability and environmental persistence vary with envelope presence, temperature, pH, and solvents; enveloped virioniin are generally more sensitive to detergents than non-enveloped ones.

Etymology reflects its relation to virus and the -ion suffix; virioniin is a variant form encountered in some linguistic or historical contexts. See also virion, virus, virology.