What is the difference between a capsid and a Capsomere?

The key difference between capsid and capsomere is that capsid is the protein coat that surrounds and protects the viral genome while capsomere is the structural subunit of a viral capsid and aggregation of several protomers as a unit. They are the protein shell and the nucleic acid genome.

What is the difference between capsid and nucleocapsid?

The key difference between capsid and nucleocapsid is that capsid is the protein coat that surrounds nucleic acid of the virus particle while nucleocapsid is the capsid together with the nucleic acids of a virus. Viruses are infective particles composed of nucleic acid molecules covered with protein capsids.

What is meant by protomers?

In structural biology, a protomer is the structural unit of an oligomeric protein. It is the smallest unit composed of at least two different protein chains that form a larger hetero-oligomer by association of two or more copies of this unit.

What is a helical capsid?

Helical capsids are made up of a single type of protein subunit stacked around a central axis to form a helical structure. The helix may have a hollow center, which makes it look like a hollow tube. This arrangement results in rod-shaped or filamentous virions.

What is a Capsomere in a virus?

Capsomere: The clusters of subunits on the capsid as seen in electron micrographs; also termed Morphological subunit. Encapsidation (or encapsulation): The process of enclosing the viral genomic nucleic acid in virus-encoded protein usually to form a virus particle.

What is the difference between helical and icosahedral viruses?

A helical virus is a virus that has a capsid shaped in a filamentous or rod-shaped structure that has a central cavity that encloses its nucleic acid. An icosahedral virus is a virus consisting of identical subunits that make up equilateral triangles that are in turn arranged in a symmetrical fashion.

What is the function of Peplomers?

Retroviruses such as the human immunodeficiency virus (HIV) have surface peplomers. These are protein complexes formed by two proteins, gp41 and gp120, both expressed from the env gene, collectively forming a spike protein complex that mediates viral entry.

What is a virion vs virus?

A virion is an entire virus particle consisting of an 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.

What is capsomere made of?

The penton capsomere is composed of a homotrimeric fiber and homopentameric penton base at the 12 vertices of the icosahedron. Together with fiber, penton base has a major role in Ad cellular internalization.

What is the difference between icosahedral and helical?

What is the difference between a capsid and a protomer?

Protomers are subunits of capsomeres while capsomeres are protein subunits of the viral capsid. Thus, capsomere is an aggregation of protomers while capsid is an aggregation of capsomeres. Arrangement of protomers or arrangement of capsomeres gives shape or symmetry to a particular virus.

What is a capsomere?

The capsomere is a subunit of the capsid, an outer covering of protein that protects the genetic material of a virus. Capsomeres self-assemble to form the capsid.

What are protomers in biology?

Protomers are the structural units of oligomeric proteins. Protomer contains at least two different polypeptide chains. More often, they contain several polypeptides. In viral capsids, protomers self-assemble to form capsomeres, which are the morphological units of capsids.

What are the different types of capsomeres in viruses?

Each capsomere has several protomers self-assembled with each other. Moreover, capsomeres are arranged differently in the capsid in order to provide a shape to the viral capsid. Helical, icosahedral and complex are three types of capsomere arrangements in viruses. However, the arrangement of capsomeres is unique for a particular virus.