What is "pentamer"

oligomer \o*lig"o*mer\, n. (Chem.) A molecule composed of a small number of linked monomer units; a short polymer; -- compounds called oligomers have less than one hundred monomer units and usually less than thirty. Oligomers of increasing length are called dimer, trimer, tetramer, pentamer, hexamer, heptamer, octamer, nonamer, decamer, etc. In colloquial laboratory jargon, they may also be referred to as nine-mer, ten-mer, eleven-mer, twelve-mer, etc., especially for oligomers of greater than eight units.

n. An oligomer having five subunits

A pentamer is an entity composed of five sub-units.

In chemistry, it applies to molecules made of five monomers.

In biochemistry, it applies to macromolecules, in particular to pentameric proteins, made of five proteic sub-units.

In microbiology, a pentamer is one of the proteins composing the polyhedral protein shell that encloses the bacterial micro-compartments known as carboxysomes.

In immunology, an MHC pentamer is a reagent used to detect antigen-specific CD8+ T cells.