Ergosterol: Difference between revisions
No edit summary |
Marked this version for translation |
||
| Line 1: | Line 1: | ||
<languages /> | <languages /> | ||
<translate> | <translate> | ||
<!--T:1--> | |||
{{Chembox | {{Chembox | ||
|Verifiedfields = changed | |Verifiedfields = changed | ||
| Line 43: | Line 44: | ||
}} | }} | ||
<!--T:2--> | |||
'''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>]]. | '''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>]]. | ||
<!--T:3--> | |||
==Role in fungi== | ==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. | 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. | ||
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. This advantage could be linked to the presence of two conjugated double bonds in the structure (B-ring) of ergosterol giving it antioxidant properties. | 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. This advantage could be linked to the presence of two conjugated double bonds in the structure (B-ring) of ergosterol giving it antioxidant properties. | ||
==Target for antifungal drugs== | ==Target for antifungal drugs== <!--T:4--> | ||
<!--T:5--> | |||
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. This is the basis for the use of some antifungals against West African [[African trypanosomiasis|sleeping sickness]]. | 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. This is the basis for the use of some antifungals against West African [[African trypanosomiasis|sleeping sickness]]. | ||
<!--T:6--> | |||
[[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)|hydrons]]) and other molecules to leak out, which will kill the cell. 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. | [[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)|hydrons]]) and other molecules to leak out, which will kill the cell. 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. | ||
<!--T:7--> | |||
[[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]]. 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. | [[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]]. 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. | ||
<!--T:8--> | |||
==Target for antiprotozoal drugs== | ==Target for antiprotozoal drugs== | ||
Some protozoa, including ''[[Trichomonas]]'' and ''[[Leishmania]]'' are inhibited by drugs that target ergosterol synthesis and function | Some protozoa, including ''[[Trichomonas]]'' and ''[[Leishmania]]'' are inhibited by drugs that target ergosterol synthesis and function | ||
==As a vitamin D<sub>2</sub> precursor== | ==As a vitamin D<sub>2</sub> precursor== <!--T:9--> | ||
<!--T:10--> | |||
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]] at 0.403 mW per cm2 intensity from 30 cm distance produced time-dependent increases in vitamin D2 concentrations. | 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]] at 0.403 mW per cm2 intensity from 30 cm distance produced time-dependent increases in vitamin D2 concentrations. | ||
<!--T:11--> | |||
This happens naturally to a certain extent, and many mushrooms are irradiated after harvest to increase their [[vitamin D]] content. Fungi are also grown industrially so that ergosterol can be extracted and converted to Vitamin D for sale as a [[dietary supplement]] and [[food additive]]. | This happens naturally to a certain extent, and many mushrooms are irradiated after harvest to increase their [[vitamin D]] content. Fungi are also grown industrially so that ergosterol can be extracted and converted to Vitamin D for sale as a [[dietary supplement]] and [[food additive]]. | ||
<!--T:12--> | |||
Preparations of irradiated ergosterol containing a mixture of previtamin and vitamin D<sub>2</sub> were called ''viosterol'' in the 1930s. | Preparations of irradiated ergosterol containing a mixture of previtamin and vitamin D<sub>2</sub> were called ''viosterol'' in the 1930s. | ||
<!--T:13--> | |||
==Toxicity== | ==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. | 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. | ||
<!--T:14--> | |||
== See also == | == See also == | ||
*[[Mushrooms and vitamin D]] | *[[Mushrooms and vitamin D]] | ||
<!--T:15--> | |||
{{Vitamins}} | {{Vitamins}} | ||
{{Cholesterol and steroid intermediates}} | {{Cholesterol and steroid intermediates}} | ||
{{Phytosterols}} | {{Phytosterols}} | ||
<!--T:16--> | |||
{{二次利用|date=24 February 2024}} | {{二次利用|date=24 February 2024}} | ||
[[Category:Sterols]] | [[Category:Sterols]] | ||
Latest revision as of 10:35, 11 April 2024
| |
| |
| Names | |
|---|---|
| IUPAC name
(22E)-Ergosta-5,7,22-trien-3β-ol
| |
| Systematic IUPAC name
(1R,3aR,7S,9aR,9bS,11aR)-1-[(2R,3E,5R)-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-1H-cyclopenta[a]phenanthren-7-ol | |
| Identifiers | |
3D model (JSmol)
|
|
| ChEBI | |
| ChEMBL | |
| ChemSpider | |
| EC Number |
|
| MeSH | Ergosterol |
PubChem CID
|
|
| UNII | |
| |
| |
| Properties | |
| C28H44O | |
| Molar mass | 396.65 g/mol |
| Melting point | 160 °C (320 °F; 433 K) |
| Boiling point | 250 °C (482 °F; 523 K) |
| -279.6·10−6 cm3/mol | |
Ergosterol (ergosta-5,7,22-trien-3β-ol) is a mycosterol found in cell membranes of fungi and protozoa, serving many of the same functions that cholesterol serves in animal cells. Because many fungi and protozoa cannot survive without ergosterol, the enzymes that synthesize it have become important targets for drug discovery. In human nutrition, ergosterol is a provitamin form of vitamin D2; exposure to ultraviolet (UV) light causes a chemical reaction that produces vitamin D2.
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 fungal cell membranes, serving many of the same functions that cholesterol serves in animal cells. 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. This advantage could be linked to the presence of two conjugated double bonds in the structure (B-ring) of ergosterol giving it antioxidant properties.
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 trypanosomes. This is the basis for the use of some antifungals against West African 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 hydrons) and other molecules to leak out, which will kill the cell. 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 14α-demethylase. 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 inhibit the enzyme that performs these demethylation steps in the biosynthetic pathway between lanosterol and ergosterol.
Target for antiprotozoal drugs
Some protozoa, including Trichomonas and Leishmania are inhibited by drugs that target ergosterol synthesis and function
As a vitamin D2 precursor
Ergosterol is a biological precursor of vitamin D2, the chemical name of which is ergocalciferol. Exposure of white button mushrooms to UV-C irradiation at 0.403 mW per cm2 intensity from 30 cm distance produced time-dependent increases in vitamin D2 concentrations.
This happens naturally to a certain extent, and many mushrooms are irradiated after harvest to increase their vitamin D content. Fungi are also grown industrially so that ergosterol can be extracted and converted to Vitamin D for sale as a dietary supplement and food additive.
Preparations of irradiated ergosterol containing a mixture of previtamin and vitamin D2 were called viosterol in the 1930s.
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.
See also
 | この記事は、クリエイティブ・コモンズ・表示・継承ライセンス3.0のもとで公表されたウィキペディアの項目Ergosterol(24 February 2024編集記事参照)を素材として二次利用しています。 Item:Q21913  |