Editing Putrescine (section)

==Occurrence==
Putrescine is found in all [[organism]]s.<ref name=":0">{{Cite journal |last1=Cui |first1=Jing |last2=Pottosin |first2=Igor |last3=Lamade |first3=Emmanuelle |last4=Tcherkez |first4=Guillaume |date=June 2020 |title=What is the role of putrescine accumulated under potassium deficiency? |url=https://onlinelibrary.wiley.com/doi/10.1111/pce.13740 |journal=Plant, Cell & Environment |language=en |volume=43 |issue=6 |pages=1331–1347 |doi=10.1111/pce.13740 |pmid=32017122 |s2cid=211023002 |issn=0140-7791}}</ref> Putrescine is widely found in plant tissues,<ref name=":0"/> often being the most common polyamine present within the organism. Its role in development is well documented, but recent studies have suggested that putrescine also plays a role in stress responses in plants, both to biotic and abiotic stressors.<ref>{{Cite journal |last1=González-Hernández |first1=Ana Isabel |last2=Scalschi |first2=Loredana |last3=Vicedo |first3=Begonya |last4=Marcos-Barbero |first4=Emilio Luis |last5=Morcuende |first5=Rosa |last6=Camañes |first6=Gemma |date=January 2022 |title=Putrescine: A Key Metabolite Involved in Plant Development, Tolerance and Resistance Responses to Stress |journal=International Journal of Molecular Sciences |language=en |volume=23 |issue=6 |pages=2971 |doi=10.3390/ijms23062971 |issn=1422-0067 |pmc=8955586 |pmid=35328394|doi-access=free}}</ref> The absence of putrescine in plants is associated with an increase in both parasite and fungal population in plants.

Putrescine serves an important role in a multitude of ways, which include: a [[Ion|cation]] substitute, an [[osmolyte]], or a transport protein.<ref name=":0" /> It also serves as an important regulator in a variety of surface proteins, both on the cell surface and on organelles, such as the mitochondria and chloroplasts. A recorded increase of ATP production has been found in mitochondria and ATP synthesis by chloroplasts with an increase in mitochondrial and chloroplastic putrescine, but putrescine has also been shown to function as a developmental inhibitor in some plants, which can be seen as [[dwarfism]] and late flowering in ''Arabiadopsis'' plants.<ref name=":0" />

Putrescine production in plants can also be promoted by fungi in the soil.<ref>{{Cite journal |last=Copeland |first=Charles |date=2022-04-01 |title=The feeling is mutual: Increased host putrescine biosynthesis promotes both plant and endophyte growth |url=https://doi.org/10.1093/plphys/kiac001 |journal=Plant Physiology |volume=188 |issue=4 |pages=1939–1941 |doi=10.1093/plphys/kiac001 |issn=0032-0889 |pmc=8968283 |pmid=35355052}}</ref> [[Piriformospora indica]] (''P.&nbsp;indica'') is one such fungus, found to promote putrescine production in ''[[Arabidopsis]]'' and common garden tomato plants. In a 2022 study it was shown that the presence of this fungus had a promotional effect on the growth of the root structure of plants. After [[gas chromatography]] testing, putrescine was found in higher amounts in these root structures.<ref name=":1">{{Cite journal |last1=Ioannidis |first1=Nikolaos E. |last2=Cruz |first2=Jeffrey A. |last3=Kotzabasis |first3=Kiriakos |last4=Kramer |first4=David M. |date=2012-01-12 |title=Evidence That Putrescine Modulates the Higher Plant Photosynthetic Proton Circuit |journal=PLOS ONE |language=en |volume=7 |issue=1 |pages=e29864 |doi=10.1371/journal.pone.0029864 |issn=1932-6203 |pmc=3257247 |pmid=22253808|bibcode=2012PLoSO...729864I |doi-access=free }}</ref>

Plants that had been inoculated with ''P.&nbsp;indica'' had presented an excess of arginine decarboxylase.<ref name=":1" /> This is used in the process of making putrescine in plant cells. One of the downstream effects of putrescine in root cells is the production of [[auxin]]. That same study found that putrescine added as a fertilizer showed the same results as if it was inoculated with the fungus, which was also shown in ''Arabidopsis'' and [[barley]]. The evolutionary foundations of this connection and putrescine are still unclear.

Putrescine is a component of [[bad breath]] and [[bacterial vaginosis]].<ref>{{cite journal|author1=Yeoman, CJ |author2=Thomas, SM |author3=Miller, ME |author4=Ulanov, AV |author5=Torralba, M |author6=Lucas, S |author7=Gillis, M |author8=Cregger, M |author9=Gomez, A |author10=Ho, M |author11=Leigh, SR |author12=Stumpf, R |author13=Creedon, DJ |author14=Smith, MA |author15=Weisbaum, JS |author16=Nelson, KE |author17=Wilson, BA |author18=White, BA |title=A multi-omic systems-based approach reveals metabolic markers of bacterial vaginosis and insight into the disease.|journal=PLOS ONE|year=2013|volume=8|issue=2|pages=e56111|doi=10.1371/journal.pone.0056111|pmid=23405259|pmc=3566083|bibcode=2013PLoSO...856111Y|doi-access=free}}</ref> It is also found in [[semen]] and some microalgae, together with [[spermine]] and [[spermidine]].