icosahedral virus
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An icosahedral virus is a type of virus with a symmetrical, polygonal structure, resembling a geodesic dome. This shape is formed by 20 equilateral triangles, each made of protein subunits called capsomeres. At each of the 12 vertices of this structure, there is a penton, composed of five subunits.12
These viruses exhibit three axes of rotational symmetry: fivefold, threefold, and twofold. The size of icosahedral viruses can vary, typically ranging from 20 to 150 nm in diameter, and this size is generally proportional to the amount of nucleic acid coiled inside the virion. Examples of viruses with icosahedral symmetry include adenoviruses and herpesviruses.13
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Many virions are spheroidal—actually icosahedral—the capsid having 20 triangular faces, with regularly arranged units called capsomeres, two to five or more along each side; and the nucleic acid is densely coiled within. Other virions have a capsid consisting of an irregular number of surface spikes and the nucleic acid…
Read MoreMany virions are spheroidal—actually icosahedral—the capsid having 20 triangular faces, with regularly arranged units called capsomeres, two to five or more along each side; and the nucleic acid is densely coiled within. Other virions have a capsid consisting of an irregular number of surface spikes and the nucleic acid…
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virusThe protein capsid…of the polygonal viruses are icosahedral; like a geodesic dome, they are formed by equilateral triangles, in this case 20. Each triangle is composed of protein subunits (capsomeres), often in the form of hexons (multiples of six) that are the building blocks of the capsid. There are 12 vertices (the…
Read More…of the polygonal viruses are icosahedral; like a geodesic dome, they are formed by equilateral triangles, in this case 20. Each triangle is composed of protein subunits (capsomeres), often in the form of hexons (multiples of six) that are the building blocks of the capsid. There are 12 vertices (the…
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