capsid
Quick Summary
The capsid is the protein shell that encloses a virus's nucleic acid and genetic material. It is a key component of a virion, the complete virus particle. The capsid is made up of smaller protein subunits called capsomeres.
Viruses are classified based on their capsid structure into two main types:
* Helical: These viruses have a rod-like or filamentous shape. The nucleic acid is arranged in a helix, and the protein subunits assemble around it. The tobacco mosaic virus is a well-studied example.
* Icosahedral: These viruses are polygonal, often appearing spherical. Their capsids are formed from equilateral triangles, creating a symmetrical, 20-sided structure. Many viruses, including some that infect humans, have this shape.
Some viruses also have an outer fatty membrane called an envelope, which can be inactivated by fat solvents.123
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virion…outer protein shell called a capsid and an inner core of nucleic acid (either ribonucleic or deoxyribonucleic acid—RNA or DNA). The core confers infectivity, and the capsid provides specificity to the virus. In some virions the capsid is further enveloped by a fatty membrane, in which case the virion can…
Read More…outer protein shell called a capsid and an inner core of nucleic acid (either ribonucleic or deoxyribonucleic acid—RNA or DNA). The core confers infectivity, and the capsid provides specificity to the virus. In some virions the capsid is further enveloped by a fatty membrane, in which case the virion can…
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virusThe protein capsidThe protein capsid provides the second major criterion for the classification of viruses. The capsid surrounds the virus and is composed of a finite number of protein subunits known as capsomeres, which usually associate with, or are found close to, the virion nucleic acid.
Read MoreThe protein capsid provides the second major criterion for the classification of viruses. The capsid surrounds the virus and is composed of a finite number of protein subunits known as capsomeres, which usually associate with, or are found close to, the virion nucleic acid.
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