View source for Ergosterol

{{Chembox
|Verifiedfields = changed
|Watchedfields = changed
|verifiedrevid = 461094825
|ImageFile = Ergosterol structure.svg
|ImageClass = skin-invert-image
|ImageSize = 250px
|ImageFile1 = Ergosterol molecule ball.png
|ImageClass1 = bg-transparent  
|ImageSize1 = 260
|ImageAlt1 = Ball-and-stick model of ergosterol
|IUPACName = (22''E'')-Ergosta-5,7,22-trien-3β-ol
|SystematicName = (1''R'',3a''R'',7''S'',9a''R'',9b''S'',11a''R'')-1-[(2''R'',3''E'',5''R'')-5,6-Dimethylhept-3-en-2-yl]-7-hydroxy-9a,11a-dimethyl-2,3,3a,6,7,8,9,9a,9b,10,11,11a-dodecahydro-1''H''-cyclopenta[''a'']phenanthren-7-ol
|Section1={{Chembox Identifiers
|ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}
|ChemSpiderID = 392539
|UNII_Ref = {{fdacite|correct|FDA}}
|UNII = Z30RAY509F
|InChIKey = DNVPQKQSNYMLRS-APGDWVJJBI
|StdInChI_Ref = {{stdinchicite|correct|chemspider}}
|StdInChI = 1S/C28H44O/c1-18(2)19(3)7-8-20(4)24-11-12-25-23-10-9-21-17-22(29)13-15-27(21,5)26(23)14-16-28(24,25)6/h7-10,18-20,22,24-26,29H,11-17H2,1-6H3/b8-7+/t19-,20+,22-,24+,25-,26-,27-,28+/m0/s1
|StdInChIKey_Ref = {{stdinchicite|correct|chemspider}}
|StdInChIKey = DNVPQKQSNYMLRS-APGDWVJJSA-N
|ChEMBL_Ref = {{ebicite|changed|EBI}}
|ChEMBL = 1232562
|CASNo = 57-87-4
|CASNo_Ref = {{cascite|correct|CAS}}
|EINECS = 200-352-7
|PubChem = 444679
|ChEBI_Ref = {{ebicite|correct|EBI}}
|ChEBI = 16933
|SMILES = O[C@@H]4C/C3=C/C=C1\[C@H](CC[C@]2([C@H]1CC[C@@H]2[C@@H](/C=C/[C@H](C)C(C)C)C)C)[C@@]3(C)CC4
|InChI =1/C28H44O/c1-18(2)19(3)7-8-20(4)24-11-12-25-23-10-9-21-17-22(29)13-15-27(21,5)26(23)14-16-28(24,25)6/h7-10,18-20,22,24-26,29H,11-17H2,1-6H3/b8-7+/t19-,20+,22-,24+,25-,26-,27-,28+/m0/s1
|MeSHName = Ergosterol
}}
|Section2={{Chembox Properties
|Formula = C<sub>28</sub>H<sub>44</sub>O
|MolarMass = 396.65 g/mol
|MeltingPtC = 160
|BoilingPtC = 250
|MagSus = −279.6·10<sup>−6</sup> cm<sup>3</sup>/mol
}}
}}

'''Ergosterol''' (ergosta-5,7,22-trien-3β-ol) is a [[sterol#Types|mycosterol]] found in [[cell membrane]]s of [[fungus|fungi]] and [[protozoa]], serving many of the same functions that [[cholesterol]] serves in [[animal]] [[cell (biology)|cell]]s. Because many fungi and protozoa cannot survive without ergosterol, the [[enzyme]]s that synthesize it have become important targets for [[drug discovery]]. In human nutrition, ergosterol is a [[provitamin]] form of [[ergocalciferol|vitamin D<sub>2</sub>]]; exposure to [[ultraviolet]] (UV) light causes a chemical reaction that produces [[ergocalciferol|vitamin D<sub>2</sub>]].

==Role in fungi==
Ergosterol (ergosta-5,7,22-trien-3β-ol) is a [[sterol]] found in fungi, and named after [[ergot]], the common name of members of the fungal genus ''[[Claviceps]]'' from which ergosterol was first isolated. Ergosterol is a component of [[yeast]] and other [[fungus|fungal]] [[cell membrane]]s, serving many of the same functions that cholesterol serves in animal cells.<ref>{{cite journal | vauthors = Weete JD, Abril M, Blackwell M | title = Phylogenetic distribution of fungal sterols | journal = PLOS ONE | volume = 5 | issue = 5 | article-number = e10899 | date = May 2010 | pmid = 20526375 | pmc = 2878339 | doi = 10.1371/journal.pone.0010899 | bibcode = 2010PLoSO...510899W | doi-access = free }}</ref>
Its specificity in higher fungi is thought to be related to the climatic instabilities (highly varying humidity and moisture conditions) encountered by these organisms in their typical ecological niches (plant and animal surfaces, soil). Thus, despite the added energy requirements of ergosterol synthesis (if compared to cholesterol), ergosterol is thought to have evolved as a nearly ubiquitous, evolutionarily advantageous fungal alternative to cholesterol.<ref>{{cite journal | vauthors = Dupont S, Lemetais G, Ferreira T, Cayot P, Gervais P, Beney L | title = Ergosterol biosynthesis: a fungal pathway for life on land? | journal = Evolution; International Journal of Organic Evolution | volume = 66 | issue = 9 | pages = 2961–2968 | date = September 2012 | pmid = 22946816 | doi = 10.1111/j.1558-5646.2012.01667.x | doi-access = free }}</ref> This advantage could be linked to the presence of two conjugated double bonds in the structure (B-ring) of ergosterol giving it antioxidant properties.<ref name="pmid34202105">{{cite journal | vauthors = Dupont S, Fleurat-Lessard P, Cruz RG, Lafarge C, Grangeteau C, Yahou F, Gerbeau-Pissot P, Abrahão Júnior O, Gervais P, Simon-Plas F, Cayot P, Beney L | title = Antioxidant Properties of Ergosterol and Its Role in Yeast Resistance to Oxidation | journal = Antioxidants| volume = 10 | issue = 7 | date = June 2021 | page = 1024 | pmid = 34202105 | pmc = 8300696 | doi = 10.3390/antiox10071024 | doi-access = free }}</ref> Additionally, the structure of ergosterol appears to have been finely tuned towards optimal interaction with saturated lipids.<ref>{{Cite journal |last1=Juarez-Contreras |first1=Israel |last2=Lopes |first2=Laura J. S. |last3=Holt |first3=Jamie |last4=Yu-Liao |first4=Lorena |last5=O'Shea |first5=Katherine |last6=Ruiz-Ruiz |first6=Jose |last7=Sodt |first7=Alexander |last8=Budin |first8=Itay |date=2025-04-23 |title=Structural dissection of ergosterol metabolism reveals a pathway optimized for membrane phase separation |journal=Science Advances |volume=11 |issue=17 |article-number=eadu7190 |doi=10.1126/sciadv.adu7190 |pmc=12017304 |pmid=40267201|bibcode=2025SciA...11.7190J }}</ref>

==Target for antifungal drugs==

Because ergosterol is present in cell membranes of fungi, yet absent in those of animals, it is a useful target for [[antifungal]] drugs. Ergosterol is also present in the cell membranes of some protists, such as [[Trypanosomatida|trypanosome]]s.<ref>{{cite journal | vauthors = Roberts CW, McLeod R, Rice DW, Ginger M, Chance ML, Goad LJ | title = Fatty acid and sterol metabolism: potential antimicrobial targets in apicomplexan and trypanosomatid parasitic protozoa | journal = Molecular and Biochemical Parasitology | volume = 126 | issue = 2 | pages = 129–142 | date = February 2003 | pmid = 12615312 | doi = 10.1016/S0166-6851(02)00280-3 }}</ref> This is the basis for the use of some antifungals against West African [[African trypanosomiasis|sleeping sickness]].

[[Amphotericin B]], an antifungal drug, targets ergosterol. It binds physically to ergosterol within the membrane, thus creating a polar pore in fungal membranes. This causes ions (predominantly [[potassium]] and [[hydron (chemistry)|protons]]) and other molecules to leak out, which will kill the cell.<ref>{{cite journal | vauthors = Ellis D | title = Amphotericin B: spectrum and resistance | journal = The Journal of Antimicrobial Chemotherapy | volume = 49 | pages = 7–10 | date = February 2002 | issue = Suppl 1 | pmid = 11801575 | doi = 10.1093/jac/49.suppl_1.7 | doi-access = free }}</ref> Amphotericin B has been replaced by safer agents in most circumstances, but is still used, despite its side effects, for life-threatening fungal or protozoan infections.

[[Fluconazole]], [[miconazole]], [[itraconazole]], [[clotrimazole]], and [[myclobutanil]] work in a different way, inhibiting synthesis of ergosterol from [[lanosterol]] by interfering with [[Lanosterol 14 alpha-demethylase|14α-demethylase]].<ref name="lv">{{cite journal | vauthors = Lv QZ, Yan L, Jiang YY | title = The synthesis, regulation, and functions of sterols in Candida albicans: Well-known but still lots to learn | journal = Virulence | volume = 7 | issue = 6 | pages = 649–659 | date = August 2016 | pmid = 27221657 | pmc = 4991322 | doi = 10.1080/21505594.2016.1188236 }}</ref> Ergosterol is a smaller molecule than lanosterol; it is synthesized by combining two molecules of farnesyl pyrophosphate, a 15-carbon-long terpenoid, into lanosterol, which has 30 carbons. Then, two methyl groups are removed, making ergosterol. The "azole" class of antifungal agents [[enzyme inhibitor|inhibit]] the enzyme that performs these [[demethylation]] steps in the biosynthetic pathway between lanosterol and ergosterol.<ref name=lv/>

==Target for antiprotozoal drugs==
Some protozoa, including ''[[Trichomonas]]'' and ''[[Leishmania]]'' are inhibited by drugs that target ergosterol synthesis and function<ref>{{cite journal | vauthors = Carrillo-Muñoz AJ, Tur-Tur C, Giusiano G, Marcos-Arias C, Eraso E, Jauregizar N, Quindós G | title = Sertaconazole: an antifungal agent for the topical treatment of superficial candidiasis | journal = Expert Review of Anti-Infective Therapy | volume = 11 | issue = 4 | pages = 347–358 | date = April 2013 | pmid = 23566144 | doi = 10.1586/eri.13.17 | s2cid = 24585556 | hdl = 11336/8943 | hdl-access = free }}</ref>

==As a vitamin D<sub>2</sub> precursor==

Ergosterol is a [[provitamin|biological precursor]] of [[ergocalciferol|vitamin D<sub>2</sub>]], the chemical name of which is [[ergocalciferol]]. Exposure of [[Agaricus bisporus|white button mushrooms]] to [[ultraviolet light|UV-C irradiation]] produces time-dependent increases in vitamin D2 concentrations in the mushrooms.<ref name="Koyy">{{cite journal | vauthors = Koyyalamudi SR, Jeong SC, Song CH, Cho KY, Pang G | title = Vitamin D2 formation and bioavailability from ''Agaricus bisporus'' button mushrooms treated with ultraviolet irradiation | journal = Journal of Agricultural and Food Chemistry | volume = 57 | issue = 8 | pages = 3351–3355 | date = April 2009 | pmid = 19281276 | doi = 10.1021/jf803908q | bibcode = 2009JAFC...57.3351K }}</ref><ref>{{cite web|author=Haytowitz, DB|url=https://www.ars.usda.gov/ARSUserFiles/80400525/Articles/AICR09_Mushroom_VitD.pdf|title=Vitamin D in mushrooms|publisher=US Department of Agriculture|access-date=2014-08-23|archive-date=2013-05-12|archive-url=https://web.archive.org/web/20130512123011/http://www.ars.usda.gov/SP2UserFiles/Place/12354500/Articles/AICR09_Mushroom_VitD.pdf|url-status=live}}</ref> Fungi are grown industrially to enable ergosterol [[extract|extraction]] and preparation as a powder for sale as a vitamin D<sub>2</sub> [[dietary supplement]] and [[food additive]].<ref name=Hirsch>{{cite book |first= Arnold Lippert |last= Hirsch |chapter-url= https://books.google.com/books?id=w7hMAFmsM84C&pg=PA79 |chapter= Chapter 6: Industrial Aspects of Vitamin D |title= Vitamin D: Two-Volume Set |veditors= Feldman D, Pike JW, Adam JS |publisher= Academic Press |date= 12 May 2011 |isbn= 978-0-12-381978-9}}</ref>

Preparations of irradiated ergosterol containing a mixture of previtamin and vitamin D<sub>2</sub> were called ''viosterol'' in the 1930s.<ref>{{cite journal |title= Viosterol official name for irradiated ergosterol |journal= Journal of Chemical Education |volume= 7 |issue= 1 |page= 166 |doi= 10.1021/ed007p166|year= 1930 |last1= Science Service |bibcode= 1930JChEd...7..166S }}</ref>

==Toxicity==
Ergosterol powder is an irritant to skin, eyes, and the respiratory tract. Ingestion of large amounts can cause [[hypercalcemia]], which (if prolonged) can lead to calcium salt deposits in the soft tissues and kidneys.<ref>{{cite web |url= http://fscimage.fishersci.com/msds/28224.htm |title= Material Safety Data Sheet for Ergosterol |publisher= Fisher Scientific |access-date= 2009-06-16 |archive-date= 2016-03-03 |archive-url= https://web.archive.org/web/20160303193545/http://fscimage.fishersci.com/msds/28224.htm |url-status= live }}</ref>

== See also ==
*[[Mushrooms and vitamin D]]

== References ==
{{Reflist}}

{{Vitamins}}
{{Cholesterol and steroid intermediates}}
{{Phytosterols}}
{{Authority control}}

[[Category:Sterols]]
[[Category:Nutrition]]
[[Category:Cell biology]]
[[Category:Vitamin D]]