Flagellum

For the insect anatomical structure, see Antenna (biology). For the flagella of male Solifugae, see Solifugae. For Eukaryotic only, see Cilia.

Flagellum
Structure of bacterial flagellum
SEM image of flagellated eukaryote Chlamydomonas sp. (10000×)
Identifiers
MeSHD005407
THH1.00.01.1.01032
FMA67472
Anatomical terminology

A flagellum (/fləˈdʒɛləm/; pl.: flagella) (Latin for 'whip' or 'scourge') is a hair-like appendage that protrudes from certain plant and animal sperm cells, from fungal spores (zoospores), and from a wide range of microorganisms to provide motility.[1][2][3][4] Many protists with flagella are known as flagellates.

A microorganism may have from one to many flagella. A gram-negative bacterium Helicobacter pylori, for example, uses its flagella to propel itself through the stomach to reach the mucous lining where it may colonise the epithelium and potentially cause gastritis, and ulcers – a risk factor for stomach cancer.[5] In some swarming bacteria, the flagellum can also function as a sensory organelle, being sensitive to wetness outside the cell.[6]

Across the three domains of Bacteria, Archaea, and Eukaryota, the flagellum has a different structure, protein composition, and mechanism of propulsion but shares the same function of providing motility. The Latin word flagellum means "whip" to describe its lash-like swimming motion. The flagellum in archaea is called the archaellum to note its difference from the bacterial flagellum.[7][8]

Eukaryotic flagella and cilia are identical in structure but have different lengths and functions.[9] Prokaryotic fimbriae and pili are smaller, and thinner appendages, with different functions. Cilia are attached to the surface of flagella and are used to swim or move fluid from one region to another. [10]

  1. ^ Bardy, Sonia L.; Ng, Sandy Y. M.; Jarrell, Ken F. (1 February 2003). "Prokaryotic motility structures". Microbiology. 149 (2): 295–304. doi:10.1099/mic.0.25948-0. PMID 12624192.
  2. ^ Silflow, Carolyn D.; Lefebvre, Paul A. (1 December 2001). "Assembly and Motility of Eukaryotic Cilia and Flagella. Lessons from Chlamydomonas reinhardtii". Plant Physiology. 127 (4): 1500–1507. doi:10.1104/pp.010807. PMC 1540183. PMID 11743094.
  3. ^ Jarrell, Ken F., ed. (2009). Pili and flagella: current research and future trends. Norfolk: Caister academic press. ISBN 978-1-904455-48-6.
  4. ^ Malo, Aurelio F; Gomendio, Montserrat; Garde, Julian; Lang-Lenton, Barbara; Soler, Ana J; Roldan, Eduardo R.S (22 June 2006). "Sperm design and sperm function". Biology Letters. 2 (2): 246–249. doi:10.1098/rsbl.2006.0449. PMC 1618917. PMID 17148374.
  5. ^ Lacy, BE; Rosemore, J (October 2001). "Helicobacter pylori: ulcers and more: the beginning of an era". The Journal of Nutrition. 131 (10): 2789S–2793S. doi:10.1093/jn/131.10.2789S. PMID 11584108. Archived from the original (abstract page) on 7 February 2009. Retrieved 2 June 2008.
  6. ^ Wang, Qingfeng; Suzuki, Asaka; Mariconda, Susana; Porwollik, Steffen; Harshey, Rasika M (1 June 2005). "Sensing wetness: a new role for the bacterial flagellum". The EMBO Journal. 24 (11): 2034–2042. doi:10.1038/sj.emboj.7600668. PMC 1142604. PMID 15889148.
  7. ^ Albers, Sonja-Verena; Jarrell, Ken F. (27 January 2015). "The archaellum: how archaea swim". Frontiers in Microbiology. 6: 23. doi:10.3389/fmicb.2015.00023. PMC 4307647. PMID 25699024.
  8. ^ Quax, TEF; Albers, SV; Pfeiffer, F (14 December 2018). "Taxis in archaea". Emerging Topics in Life Sciences. 2 (4): 535–546. doi:10.1042/ETLS20180089. PMC 7289035. PMID 33525831.
  9. ^ Haimo, L T; Rosenbaum, J L (1 December 1981). "Cilia, flagella, and microtubules". The Journal of Cell Biology. 91 (3): 125s–130s. doi:10.1083/jcb.91.3.125s. PMC 2112827. PMID 6459327.
  10. ^ Wan, Kirsty Y. (21 November 2018). "Coordination of eukaryotic cilia and flagella". Essays in Biochemistry. 62 (6): 829–838. doi:10.1042/ebc20180029. ISSN 0071-1365. PMC 6281475. PMID 30464007.