Editing Endosymbiont (section)

=== Protists ===
''[[Mixotricha paradoxa]]'' is a [[protozoan]] that lacks mitochondria. However, spherical bacteria live inside the cell and serve the function of the mitochondria. ''Mixotricha'' has three other species of symbionts that live on the surface of the cell.<ref>{{Cite journal |last1=Wenzel |first1=Marika |last2=Radek |first2=Renate |last3=Brugerolle |first3=Guy |last4=König |first4=Helmut |date=2003-01-01 |title=Identification of the ectosymbiotic bacteria of Mixotricha paradoxa involved in movement symbiosis |url=https://www.sciencedirect.com/science/article/pii/S0932473904700802 |journal=European Journal of Protistology |volume=39 |issue=1 |pages=11–23 |doi=10.1078/0932-4739-00893 |issn=0932-4739}}</ref>

''[[Paramecium bursaria]]'', a species of [[ciliate]], has a mutualistic symbiotic relationship with green alga called ''[[Zoochlorella]]''. The algae live in its cytoplasm.<ref>{{cite journal | pmc=3413206 | year=2012 | last1=Dziallas | first1=C. | last2=Allgaier | first2=M. | last3=Monaghan | first3=M. T. | last4=Grossart | first4=H. P. | title=Act together—implications of symbioses in aquatic ciliates | journal=Frontiers in Microbiology | volume=3 | page=288 | doi=10.3389/fmicb.2012.00288 | pmid=22891065 | doi-access=free }}</ref>

''Platyophrya chlorelligera'' is a freshwater ciliate that harbors ''[[Chlorella]]'' that perform photosynthesis.<ref>{{Cite book |last=Joint |first=Ian |url=https://books.google.com/books?id=883qCAAAQBAJ&q=Platyophrya%2520chlorelligera&pg=PA103 |title=Molecular Ecology of Aquatic Microbes |date=2013-06-29 |publisher=Springer Science & Business Media |isbn=978-3-642-79923-5 |language=en}}</ref><ref>{{cite journal | url=https://pubmed.ncbi.nlm.nih.gov/23196282/ | pmid=23196282 | year=1991 | last1=Kawakami | first1=H. | title=An endosymbiotic Chlorella-bearing ciliate: Platyophrya chlorelligera Kawakami 1989 | journal=European Journal of Protistology | volume=26 | issue=3–4 | pages=245–255 | doi=10.1016/S0932-4739(11)80146-X }}</ref>

''Strombidium purpureum'' is a marine ciliate that uses endosymbiotic, purple, non-sulphur bacteria for anoxygenic photosynthesis.<ref>{{Cite journal |doi=10.1111/j.1574-6968.1993.tb06289.x |title=Endosymbiotic purple non-sulphur bacteria in an anaerobic ciliated protozoon |year=1993 |last1=Fenchel |first1=Tom |last2=Bernard |first2=Catherine |journal=FEMS Microbiology Letters |volume=110 |pages=21–25 |s2cid=86458030 |doi-access=free }}</ref><ref>{{Cite book |last1=Paracer |first1=Surindar |url=https://books.google.com/books?id=OmZ6CfHQIZ8C&q=Strombidium%2520purpureum&pg=PA47 |title=Symbiosis: An Introduction to Biological Associations |last2=Ahmadjian |first2=Vernon |date=2000-07-06 |publisher=Oxford University Press |isbn=978-0-19-802788-1 |language=en}}</ref>

''[[Paulinella|Paulinella chromatophora]]'' is a freshwater [[amoeboid]] that has a [[cyanobacterium]] endosymbiont.

Many [[foraminifera]] are hosts to several types of algae, such as [[red algae]], [[diatom]]s, [[dinoflagellate]]s and [[chlorophyta]].<ref>{{cite book|author1=Joseph Seckbach|author2=Patrick Kociolek|title=The Diatom World|url=https://books.google.com/books?id=Va35Mtn9VGYC&pg=PA439|year=2011|publisher=Springer Science & Business Media|isbn=978-94-007-1327-7|page=439}}</ref> These endosymbionts can be transmitted vertically to the next generation via asexual reproduction of the host, but because the endosymbionts are larger than the foraminiferal [[gamete]]s, they need to acquire algae horizontally following sexual reproduction.<ref>{{cite thesis | url=https://theses.hal.science/tel-01760725 | title=Origins and early evolution of photosynthetic eukaryotes | date=5 March 2018 | publisher=Université Paris-Saclay | last1=Toledo | first1=Rafael Isaac Ponce  |s2cid=89705815}}</ref>

Several species of [[radiolaria]] have photosynthetic symbionts. In some species the host digests algae to keep the population at a constant level.<ref>{{cite book|author1=Surindar Paracer|author2=Vernon Ahmadjian|title=Symbiosis: An Introduction to Biological Associations|url=https://books.google.com/books?id=Z3Y8DwAAQBAJ&pg=PA155|year=2000|publisher=Oxford University Press|isbn=978-0-19-511807-0|page=155}}</ref>

''[[Hatena arenicola]]'' is a flagellate [[protist]] with a complicated feeding apparatus that feeds on other microbes. When it engulfs a green ''[[Nephroselmis]]'' alga, the feeding apparatus disappears and it becomes photosynthetic. During [[mitosis]] the algae is transferred to only one of the daughter cells, while the other cell restarts the cycle.

In 1966, biologist Kwang W. Jeon found that a lab strain of ''[[Amoeba proteus]]'' had been infected by bacteria that lived inside the cytoplasmic [[vacuoles]].<ref>{{cite journal |vauthors=Jeon KW, Jeon MS |title=Endosymbiosis in amoebae: recently established endosymbionts have become required cytoplasmic components |journal=Journal of Cellular Physiology |volume=89 |issue=2 |pages=337–344 |date=October 1976 |pmid=972171 |doi=10.1002/jcp.1040890216 |s2cid=32044949 }}</ref> This infection killed almost all of the infected protists. After the equivalent of 40 host generations, the two organisms become mutually interdependent. A genetic exchange between the [[prokaryotes]] and protists occurred.<ref>{{cite web|url=https://bcmb.utk.edu/people/emeritus/kwang-w-jeon/|title=Kwang W. Jeon {{!}} Biochemistry & Cellular and Molecular Biology – UTK BCMB|date=28 April 2014|access-date=14 May 2019|archive-date=31 August 2018|archive-url=https://web.archive.org/web/20180831181533/https://bcmb.utk.edu/people/emeritus/kwang-w-jeon/|url-status=dead}}</ref><ref>{{cite book|author1=Luigi Nibali|author2=Brian Henderson|title=The Human Microbiota and Chronic Disease: Dysbiosis as a Cause of Human Pathology|url=https://books.google.com/books?id=sQ6lDAAAQBAJ&pg=PA165|year=2016|publisher=John Wiley & Sons|isbn=978-1-118-98287-7|page=165}}</ref><ref>K. Jeon, "Amoeba and X-bacteria: Symbiont Acquisition and Possible Species Change," in: L. Margulis and R. Fester, eds., ''Symbiosis as a Source of Evolutionary Innovation'' (Cambridge, Mass.: MIT Press), c. 9.</ref>