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  • Current: Feb 28, 2021

Pilus (pl. Pili)

Pili are protein structures that extend from the surface of cells. There are two types of pili: attachment pili help bacteria adhere to surface; sex pili assist in the transfer of plasmids, small circular DNAs that typically encode genes necessary for bacterial survival in certain environments.

Structure of prokaryotic cells

Some prokaryotic cells also have a flagellum, a long, hair-like structure used for the movement.


Definitions in the literature

  • a hair-like protein structure that projects from the cell wall of many bacteria. Attachment pili help bacteria adhere to structures. Sex pili assist in the transfer of plasmids [1].
  • A protein filament that projects from the surface of some prokaryotic cells [2].