Editing Microbial ecology (section)

== Microbial Symbiotic Relationships ==
=== Mutualism ===
Mutualism is a close relationship between two different species in which each has a positive effect on the other . In mutualism, one partner provides service to the other partner and also receives service from the other partner as well.<ref>{{Cite book |url=https://academic.oup.com/book/27600 |title=Mutualism |date=2015-07-01 |publisher=Oxford University Press |isbn=978-0-19-180942-2 |language=en |doi=10.1093/acprof:oso/9780199675654.001.0001 |editor-last1=Bronstein |editor-first1=Judith L.}}</ref> Mutualism in microbial ecology is a relationship between microbial species and other species (example humans) that allows for both sides to benefit.<ref name=":42">{{Cite book |title=Understanding bacteria |last=Sheela |first=Srivastava |date=2003 |publisher=Kluwer Academic Publishers |others=Srivastava, P. S. |isbn=978-1-4020-1633-2 |location=Dordrecht |oclc=53231924}}</ref> Microorganisms form mutualistic relationship with other microorganism, plants or animals. One example of microbe-microbe interaction would be  [[syntrophy]], also known as cross-feeding,<ref>{{cite journal |last1=Faust |first1=Karoline |last2=Raes |first2=Jeroen |date=July 16, 2012 |title=Microbial interactions: from networks to models |journal=Nature Reviews. Microbiology |volume=10 |issue=8 |pages=538–550 |doi=10.1038/nrmicro2832 |pmid=22796884 |s2cid=22872711}}</ref> of which ''Methanobacterium omelianskii'' is a classical example.<ref>{{Cite journal|last1=Bryant|first1=M. P.|last2=Wolin|first2=E. A.|last3=Wolin|first3=M. J.|last4=Wolfe|first4=R. S.|date=1967|title=Methanobacillus omelianskii, a symbiotic association of two species of bacteria|journal=Archiv für Mikrobiologie|volume=59|issue=1–3|pages=20–31|doi=10.1007/bf00406313|pmid=5602458|bibcode=1967ArMic..59...20B |s2cid=10348127|issn=0302-8933}}</ref><ref name=":2" /> This consortium is formed by an ethanol fermenting organism and a [[methanogen]]. The ethanol-fermenting organism provides the archaeal partner with the H<sub>2</sub>, which this methanogen needs in order to grow and produce methane.<ref name=":13">{{Cite book |last=Kirchman |first=David L |title=Processes in microbial ecology |date=2012 |publisher=Oxford University Press |isbn=978-0-19-958693-6 |location=Oxford |oclc=777261246}}</ref><ref name=":2">{{Cite journal |last1=López-García |first1=Purificación |last2=Eme |first2=Laura |last3=Moreira |first3=David |date=December 2017 |title=Symbiosis in eukaryotic evolution |journal=Journal of Theoretical Biology |series=The origin of mitosing cells: 50th anniversary of a classic paper by Lynn Sagan (Margulis) |volume=434 |issue=Supplement C |pages=20–33 |doi=10.1016/j.jtbi.2017.02.031|pmid=28254477 |pmc=5638015 |bibcode=2017JThBi.434...20L}}</ref> Syntrophy has been hypothesized to play a significant role in energy and nutrient-limited environments, such as deep subsurface, where it can help the microbial community with diverse functional properties to survive, grow and produce maximum amount of energy.<ref>{{Cite journal|last1=Lau|first1=Maggie C. Y.|last2=Kieft|first2=Thomas L.|last3=Kuloyo|first3=Olukayode|last4=Linage-Alvarez|first4=Borja|last5=van Heerden|first5=Esta|last6=Lindsay|first6=Melody R.|last7=Magnabosco|first7=Cara|last8=Wang|first8=Wei|last9=Wiggins|first9=Jessica B.|last10=Guo|first10=Ling|last11=Perlman|first11=David H.|date=December 6, 2016|title=An oligotrophic deep-subsurface community dependent on syntrophy is dominated by sulphur-driven autotrophic denitrifiers|journal=Proceedings of the National Academy of Sciences|language=en|volume=113|issue=49|pages=E7927–E7936|doi=10.1073/pnas.1612244113|issn=0027-8424|pmc=5150411|pmid=27872277|bibcode=2016PNAS..113E7927L |doi-access=free}}</ref><ref>{{Citation|last1=Schink|first1=Bernhard|title=Syntrophism Among Prokaryotes|date=2013|work=The Prokaryotes|pages=471–493|publisher=Springer Berlin Heidelberg|isbn=978-3-642-30122-3|last2=Stams|first2=Alfons J. M.|doi=10.1007/978-3-642-30123-0_59|url=http://nbn-resolving.de/urn:nbn:de:bsz:352-276499|url-access=subscription}}</ref>  [[Anaerobic oxidation of methane]] (AOM) is carried out by mutualistic consortium of a [[Sulfate-reducing microorganisms|sulfate-reducing bacterium]] and an anaerobic [[Anaerobic oxidation of methane|methane-oxidizing archaeon]].<ref>{{Cite journal|last1=Boetius|first1=Antje|last2=Ravenschlag|first2=Katrin|last3=Schubert|first3=Carsten J.|last4=Rickert|first4=Dirk|last5=Widdel|first5=Friedrich|last6=Gieseke|first6=Armin|last7=Amann|first7=Rudolf|last8=Jørgensen|first8=Bo Barker|last9=Witte|first9=Ursula|last10=Pfannkuche|first10=Olaf|date=October 2000|title=A marine microbial consortium apparently mediating anaerobic oxidation of methane|journal=Nature|volume=407|issue=6804|pages=623–626|doi=10.1038/35036572|pmid=11034209|issn=0028-0836|bibcode=2000Natur.407..623B|s2cid=205009562}}</ref><ref>{{Cite journal|last1=Raghoebarsing|first1=Ashna A.|last2=Pol|first2=Arjan|last3=van de Pas-Schoonen|first3=Katinka T.|last4=Smolders|first4=Alfons J. P.|last5=Ettwig|first5=Katharina F.|last6=Rijpstra|first6=W. Irene C.|last7=Schouten|first7=Stefan|last8=Damsté|first8=Jaap S. Sinninghe|last9=Op den Camp|first9=Huub J. M.|last10=Jetten|first10=Mike S. M.|last11=Strous|first11=Marc|date=April 2006|title=A microbial consortium couples anaerobic methane oxidation to denitrification|journal=Nature|volume=440|issue=7086|pages=918–921|doi=10.1038/nature04617|pmid=16612380|issn=0028-0836|hdl=1874/22552|bibcode=2006Natur.440..918R|s2cid=4413069|url=https://repository.ubn.ru.nl//bitstream/handle/2066/36167/36167.pdf |hdl-access=free}}</ref> The reaction used by the bacterial partner for the production of H<sub>2</sub> is [[Endergonic reaction|endergonic]] (and so thermodynamically unfavored) however, when coupled to the reaction used by archaeal partner, the overall reaction becomes [[Exergonic process|exergonic]].<ref name=":13" /> Thus the two organisms are in a mutualistic relationship which allows them to grow and thrive in an environment, deadly for either species alone. [[Lichen]] is an example of a symbiotic organism.<ref name=":2" />

Microorganisms also engage in mutualistic relationship with plants and a typical example of such relationship is arbuscular mycorrhizal (AM) relationship, a symbiotic relationship between plants and fungi.<ref name=":5">{{Citation |last1=Smith |first1=Sally E. |title=INTRODUCTION |date=2008 |work=Mycorrhizal Symbiosis |pages=1–9 |url=http://dx.doi.org/10.1016/b978-012370526-6.50002-7 |access-date=2024-10-12 |publisher=Elsevier |isbn=978-0-12-370526-6 |last2=Read |first2=David|doi=10.1016/b978-012370526-6.50002-7|url-access=subscription }}</ref>  This relationship begins when chemical signals are exchange between the plant and the fungi leading to the metabolic stimulation of the fungus.<ref>{{Cite journal |last1=Besserer |first1=Arnaud |last2=Puech-Pagès |first2=Virginie |last3=Kiefer |first3=Patrick |last4=Gomez-Roldan |first4=Victoria |last5=Jauneau |first5=Alain |last6=Roy |first6=Sébastien |last7=Portais |first7=Jean-Charles |last8=Roux |first8=Christophe |last9=Bécard |first9=Guillaume |last10=Séjalon-Delmas |first10=Nathalie |date=2006-06-27 |title=Strigolactones Stimulate Arbuscular Mycorrhizal Fungi by Activating Mitochondria |journal=PLOS Biology |volume=4 |issue=7 |pages=e226 |doi=10.1371/journal.pbio.0040226 |doi-access=free |pmid=16787107 |pmc=1481526 |issn=1545-7885}}</ref><ref>{{Cite journal |last=Harrison |first=Maria J. |date=December 2012 |title=Cellular programs for arbuscular mycorrhizal symbiosis |url=http://dx.doi.org/10.1016/j.pbi.2012.08.010 |journal=Current Opinion in Plant Biology |volume=15 |issue=6 |pages=691–698 |doi=10.1016/j.pbi.2012.08.010 |pmid=23036821 |bibcode=2012COPB...15..691H |issn=1369-5266|url-access=subscription }}</ref> The fungus then attacks the epidermis of the plant’s root and penetrates its highly branched hyphae into the cortical cells of the plant.<ref name=":5" /> In this relationship, the fungi gives the plant phosphate and nitrogen obtained from the soil with the plant in return providing the fungi with carbohydrate and lipids obtained from photosynthesis.<ref>{{Cite journal |journal=Science |last1=Shiu |first1=Patrick |last2=Xiao |first2=Hua |date=2021-05-28 |title=Faculty Opinions recommendation of Lipid exchanges drove the evolution of mutualism during plant terrestrialization. |doi=10.3410/f.740146041.793585932 |doi-access=free}}</ref> Also, microorganisms are involve in mutualistic relationship with mammals such as humans. As the host provides shelter and nutrient to the microorganisms, the microorganisms also provide benefits such as helping in the growth of the gastrointestinal tract of the host and protecting host from other detrimental microorganisms.<ref>{{Cite journal |last1=Leser |first1=Thomas D. |last2=Mølbak |first2=Lars |date=September 2009 |title=Better living through microbial action: the benefits of the mammalian gastrointestinal microbiota on the host |url=https://sfamjournals.onlinelibrary.wiley.com/doi/10.1111/j.1462-2920.2009.01941.x |journal=Environmental Microbiology |language=en |volume=11 |issue=9 |pages=2194–2206 |doi=10.1111/j.1462-2920.2009.01941.x |pmid=19737302 |bibcode=2009EnvMi..11.2194L |issn=1462-2912}}</ref>

=== Commensalism ===
Commensalism is very common in microbial world, literally meaning "eating from the same table".<ref>{{Citation|last1=Bogitsh|first1=Burton J.|title=Symbiosis and Parasitism|date=2013|work=Human Parasitology|pages=1–13|publisher=Elsevier|isbn=978-0-12-415915-0|last2=Carter|first2=Clint E.|last3=Oeltmann|first3=Thomas N.|doi=10.1016/b978-0-12-415915-0.00001-7|s2cid=88750087}}</ref> It is a relationship between two species where one species benefits with no harm or benefit for the other species.<ref name="annualreviews.org" />  Metabolic products of one microbial population are used by another microbial population without either gain or harm for the first population. There are many "pairs "of microbial species that perform either oxidation or reduction reaction to the same chemical equation. For example, methanogens produce methane by reducing CO<sub>2</sub> to CH<sub>4</sub>, while [[methanotroph]]s oxidise methane back to CO<sub>2</sub>.<ref>{{Citation|last1=Canfield|first1=Donald E.|title=Structure and Growth of Microbial Populations|date=2005|work=Advances in Marine Biology|pages=23–64|publisher=Elsevier|isbn=978-0-12-026147-5|last2=Erik Kristensen|last3=Bo Thamdrup|doi=10.1016/s0065-2881(05)48002-5}}</ref>

=== Amensalism ===
[[Amensalism]] (also commonly known as antagonism) is a type of symbiotic relationship where one species/organism is harmed while the other remains unaffected.<ref name=":42" /> One example of such a relationship that takes place in microbial ecology is between the microbial species ''[[Lactobacillus casei]]'' and ''[[Pseudomonas taetrolens]]''.<ref>{{cite journal |last1=García |first1=Cristina |last2=Rendueles |first2=Manuel |last3=Díaz |first3=Mario |date=September 2017 |title=Synbiotic Fermentation for the Co-Production of Lactic and Lactobionic Acids from Residual Dairy Whey |journal=Biotechnology Progress |volume=33 |issue=5 |pages=1250–1256 |doi=10.1002/btpr.2507 |pmid=28556559|s2cid=23694837}}</ref> When co-existing in an environment, ''Pseudomonas taetrolens'' shows inhibited growth and decreased production of lactobionic acid (its main product) most likely due to the byproducts created by ''Lactobacillus casei'' during its production of lactic acid.<ref>{{Cite book |title=The microbial challenge : science, disease, and public health |last=Krasner|first=Robert I. |date=2010 |publisher=Jones and Bartlett Publishers |isbn=978-0-7637-5689-5 |edition=2nd |location=Sudbury, Mass. |oclc=317664342}}</ref>

=== Parasitism ===
Certain microorganisms are known to have a host-parasite interaction with other organisms. For example, phytopathogenic fungi are known to infect and damage plants.<ref name=":05">{{Citation |last=Coque |first=Juan José R. |title=Chapter Four - Advances in the control of phytopathogenic fungi that infect crops through their root system |date=2020-01-01 |work=Advances in Applied Microbiology |volume=111 |pages=123–170 |editor-last=Gadd |editor-first=Geoffrey Michael |url=https://www.sciencedirect.com/science/article/abs/pii/S0065216420300058 |access-date=2025-04-03 |publisher=Academic Press |last2=Álvarez-Pérez |first2=José Manuel |last3=Cobos |first3=Rebeca |last4=González-García |first4=Sandra |last5=Ibáñez |first5=Ana M. |last6=Diez Galán |first6=Alba |last7=Calvo-Peña |first7=Carla |editor2-last=Sariaslani |editor2-first=Sima}}</ref> The phytopathogenic fungi is a major issue in agriculture, because it has the capacity to infect its host by their root system.<ref name=":05" /> This is a major issue because the symptoms of the infection are not easily detected.<ref name=":05" /> Another example of a parasitic microorganism is the [[nematode]].<ref name=":15">{{Cite journal |last=Castillo |first=Julio Cesar |last2=Reynolds |first2=Stuart E. |last3=Eleftherianos |first3=Ioannis |date=2011-12-01 |title=Insect immune responses to nematode parasites |url=https://www.sciencedirect.com/science/article/abs/pii/S1471492211001632 |journal=Trends in Parasitology |volume=27 |issue=12 |pages=537–547 |doi=10.1016/j.pt.2011.09.001 |issn=1471-4922|url-access=subscription }}</ref> These organisms are known to cause [[Onchocerciasis|river blindness]] and [[lymphatic filariasis]] in humans.<ref name=":15" /> These organisms are transmitted to hosts through different mosquito species from the following groups: [[Aedes]], [[Anopheles]], and [[Culex]].<ref name=":15" />