Virus Classification and Structure

• In the late 19th century, scientists discovered viruses by observing an infectious agent too small to be seen with a light microscope, which could pass through bacterial filters.
• Viruses are composed of genetic material (RNA or DNA) enclosed in a protein coat, and they rely on host cells for replication as they can't move or replicate on their own.
• Viruses are not considered alive by most scientists and are classified into RNA or DNA viruses, with varying genome structures (circular or linear, single or double-stranded).
• Viruses come in different shapes such as helical, icosahedral, or complex, with specific protein components that help them bind to host cell receptors.
• The International Committee on Taxonomy of Viruses (ICTV) classifies viruses into species, genus, subfamily, family, and order based on virion characteristics and genome properties.
• Virus names lack a consistent pattern, with families typically ending in -viridae, while informal names are commonly used by virologists.
• Viral classification is based on criteria like morphology, structural proteins, and genome properties to group viruses into taxonomic categories.

Learn about the discovery, structure, classification, and naming conventions of viruses, including their genetic material, protein coat, shapes, and classification criteria based on genome properties. Explore how viruses are classified by the International Committee on Taxonomy of Viruses (ICTV).