Editing Neisseria gonorrhoeae (section)

==== Type IV pili ====
[[File:Type IV Pilus Twitching Motility Steps.svg|thumb|511x511px|''Neisseria gonorrhoeae'' use their type IV pili as a motility structure. These are the steps for the type IV pilus twitching motility mechanism.]]
Dynamic [[polymer]]ic protein filaments called [[Type IV pilus|type IV pili]] allow ''N. gonorrhoeae'' to do many bacterial processes including adhesion to surfaces, transformation competence, twitching motility, and immune response evasions.<ref name="Green_2022">{{cite book |doi=10.1016/bs.ampbs.2022.01.002 |title=Neisseria gonorrhoeae physiology and pathogenesis |series=Advances in Microbial Physiology |date=2022 |volume=80 |pages=35–83 |pmid=35489793 |isbn=978-0-323-98869-8 | vauthors = Green LR, Cole J, Parga EF, Shaw JG }}</ref> To enter the host the bacteria uses the pili to adhere to and penetrate mucosal surfaces. The pili are a pivotal [[virulence factor]] for ''N. gonorrhoeae''; without them, the bacterium is unable to promote colonization.<ref name="Hu_2020">{{cite journal | vauthors = Hu LI, Yin S, Ozer EA, Sewell L, Rehman S, Garnett JA, Seifert HS | title = Discovery of a New Neisseria gonorrhoeae Type IV Pilus Assembly Factor, TfpC | journal = mBio | volume = 11 | issue = 5 | date = October 2020 | pmid = 33109763 | doi = 10.1128/mBio.02528-20 | veditors = Justice S | pmc = 7593972 }}</ref> For motility, individual bacteria use their pili in a manner that resembles a grappling hook: first, they are extended from the cell surface and attach to a [[Substrate (biology)|substrate]]. Subsequent pilus retraction drags the cell forward. The resulting movement is referred to as twitching motility. ''N. gonorrhoeae'' is able to pull 100,000 times its own weight,<ref name="Merz_2000">{{cite journal | vauthors = Merz AJ, So M, Sheetz MP | title = Pilus retraction powers bacterial twitching motility | journal = Nature | volume = 407 | issue = 6800 | pages = 98–102 | date = September 2000 | pmid = 10993081 | doi = 10.1038/35024105 | bibcode = 2000Natur.407...98M }}</ref> and the pili used to do so are amongst the strongest biological motors known to date, exerting one [[Newton (unit)|nanonewton]].<ref name="Merz_2000" /> The PilF and PilT [[ATPase]] proteins are responsible for powering the extension and retraction of the type IV pilus, respectively. The adhesive functions of the gonococcal pilus play a role in [[microcolony]] aggregation and [[biofilm]] formation. These pili are also used to avoid immune responses from the cell they are invading by having their type IV pili antigenically vary. The main pilus filament is replaced by variable DNA sequences very frequently.<ref name="Green_2022" /> By doing this process rapidly, they are able to create a diversity of pili on their surface and evade the host cell's immune response.<ref name="Hu_2020" />