Scytonemin (original) (raw)
Scytonemin je žlutohnědý pigment sinic, který funguje jako ochrana proti ultrafialovému záření. Vzniká kondenzací tryptofanu a fenylpropanu. Lokalizuje se na vnější straně buněčné stěny sinic.
| Property | Value |
|---|---|
| dbo:abstract | Scytonemin je žlutohnědý pigment sinic, který funguje jako ochrana proti ultrafialovému záření. Vzniká kondenzací tryptofanu a fenylpropanu. Lokalizuje se na vnější straně buněčné stěny sinic. (cs) Scytonemin is a secondary metabolite and an extracellular matrix (sheath) pigment synthesized by many strains of cyanobacteria, including Nostoc, Scytonema, Calothrix, Lyngbya, Rivularia, Chlorogloeopsis, and Hyella. Scytonemin-synthesizing cyanobacteria often inhabit highly insolated terrestrial, freshwater and coastal environments such as deserts, semideserts, rocks, cliffs, marine intertidal flats, and hot springs. The pigment was originally discovered in 1849 by Swiss botanist Carl Nägeli, although the structure remained unsolved until 1993. It is an aromatic indole alkaloid built from two identical condensation products of tryptophanyl- and tyrosyl-derived subunits linked through a carbon-carbon bond. Depending on the redox conditions it can exist in two inter-convertible forms: a more common oxidized yellow-brown form which is insoluble in water and only slightly soluble in organic solvents, such as pyridine, and a reduced form with bright red color that is more soluble in organic solvents. Scytonemin absorbs very strongly and very broadly across the UV-C-UV-B-UV-A-violet-blue spectral region, with an in vivo maximum absorption at 370 nm and an in vitro maximum absorption at 386 and 252 nm, and with smaller peaks at 212, 278 and 300 nm. It is believed that scytonemin acts as a highly efficient protective biomolecule (sunscreen) that filters out damaging high frequency UV rays while at the same time allowing the transmittance of wavelengths necessary for photosynthesis. Its biosynthesis in cyanobacteria is mostly triggered by exposure to UV-A and UV-B wavelengths. Recently, Couradeau and coworkers found that cyanobacterial soil crusts warm the soil surface by as much as 10 °C through the production and accumulation of scytonemin pigments. This effect is due to the dissipation of the absorbed photons by the scytonemin molecules into heat. (en) 伪枝藻素（英語：Scytonemin）是一种生物色素，由许多藍细菌合成，包括Calothrix sp.、Lyngbya aestuarii等，最早在1849被人发现，但直到1993年才解析了其结构。据信，伪枝藻素对细菌起到了防曬油的作用，在325-425 nm的有很大的吸收峰，并在250 nm的紫外波段有个独立的吸收峰，在暴露在紫外线的情况下才启动它的生物合成。 (zh) |
| dbo:alternativeName | Scytonemin (en) |
| dbo:iupacName | (3E,3′E)-3,3′-Bis[(4-hydroxyphenyl)methylidene][1,1′-bi(cyclopropa[b]indole)]-2,2′(3H,3′H)-dione (en) |
| dbo:thumbnail | wiki-commons:Special:FilePath/Scytonemin.png?width=300 |
| dbo:wikiPageID | 31938922 (xsd:integer) |
| dbo:wikiPageLength | 9646 (xsd:nonNegativeInteger) |
| dbo:wikiPageRevisionID | 1105940601 (xsd:integer) |
| dbo:wikiPageWikiLink | dbr:Carl_Nägeli dbr:Pyridine dbr:Electromagnetic_spectrum dbr:Nostoc dbr:Alkaloid dbc:Biological_pigments dbc:Cyanobacteria dbr:In_vitro dbr:In_vivo dbr:Transmittance dbr:Aromaticity dbr:Calothrix_crustacea dbr:Chlorogloeopsis dbr:Hot_spring dbr:Visible_spectrum dbr:Sunscreen dbc:Secondary_metabolites dbr:Tryptophan dbr:Tyrosine dbr:Dissipation dbr:Cyanobacteria dbr:Redox dbr:Heat dbr:Absorption_(electromagnetic_radiation) dbr:Biological_pigment dbr:Biological_soil_crust dbr:Biosynthesis dbr:Uv-B dbr:Photon dbr:Photosynthesis dbr:Ultraviolet dbr:Scytonema dbr:Extracellular_matrix dbr:Lyngbya dbr:Secondary_metabolite dbr:Mudflat dbr:UV_A dbr:P-hydroxyphenylpyruvic_acid dbr:Oxidized dbr:UV_light dbr:File:Scytonemin_biosynthesis.png |
| dbp:imagefile | Scytonemin.png (en) |
| dbp:imagesize | 200 (xsd:integer) |
| dbp:othernames | Scytonemin (en) |
| dbp:pin | -33 (xsd:integer) |
| dbp:verifiedfields | changed (en) |
| dbp:verifiedrevid | 431787953 (xsd:integer) |
| dbp:watchedfields | changed (en) |
| dbp:wikiPageUsesTemplate | dbt:Chembox dbt:Chembox_Hazards dbt:Chembox_Identifiers dbt:Chembox_Properties dbt:Cascite dbt:Chemspidercite dbt:Ebicite dbt:Fdacite dbt:Stdinchicite |
| dcterms:subject | dbc:Biological_pigments dbc:Cyanobacteria dbc:Secondary_metabolites |
| gold:hypernym | dbr:Pigment |
| rdf:type | owl:Thing dul:ChemicalObject dbo:ChemicalSubstance wikidata:Q11173 yago:WikicatBiologicalPigments yago:Abstraction100002137 yago:ColoringMaterial114984973 yago:Material114580897 yago:Matter100020827 yago:Part113809207 yago:PhysicalEntity100001930 yago:Pigment114989820 yago:Relation100031921 dbo:ChemicalCompound yago:Substance100019613 |
| rdfs:comment | Scytonemin je žlutohnědý pigment sinic, který funguje jako ochrana proti ultrafialovému záření. Vzniká kondenzací tryptofanu a fenylpropanu. Lokalizuje se na vnější straně buněčné stěny sinic. (cs) 伪枝藻素（英語：Scytonemin）是一种生物色素，由许多藍细菌合成，包括Calothrix sp.、Lyngbya aestuarii等，最早在1849被人发现，但直到1993年才解析了其结构。据信，伪枝藻素对细菌起到了防曬油的作用，在325-425 nm的有很大的吸收峰，并在250 nm的紫外波段有个独立的吸收峰，在暴露在紫外线的情况下才启动它的生物合成。 (zh) Scytonemin is a secondary metabolite and an extracellular matrix (sheath) pigment synthesized by many strains of cyanobacteria, including Nostoc, Scytonema, Calothrix, Lyngbya, Rivularia, Chlorogloeopsis, and Hyella. Scytonemin-synthesizing cyanobacteria often inhabit highly insolated terrestrial, freshwater and coastal environments such as deserts, semideserts, rocks, cliffs, marine intertidal flats, and hot springs. (en) |
| rdfs:label | Scytonemin (cs) Scytonemin (en) 伪枝藻素 (zh) |
| owl:sameAs | freebase:Scytonemin yago-res:Scytonemin wikidata:Scytonemin http://azb.dbpedia.org/resource/اسکیتونمین dbpedia-cs:Scytonemin dbpedia-fa:Scytonemin dbpedia-mk:Scytonemin dbpedia-sr:Scytonemin dbpedia-zh:Scytonemin https://global.dbpedia.org/id/4ut2C |
| prov:wasDerivedFrom | wikipedia-en:Scytonemin?oldid=1105940601&ns=0 |
| foaf:depiction | wiki-commons:Special:FilePath/Scytonemin.png wiki-commons:Special:FilePath/Scytonemin_biosynthesis.png |
| foaf:isPrimaryTopicOf | wikipedia-en:Scytonemin |
| is dbo:wikiPageWikiLink of | dbr:Emily_Balskus dbr:4-Hydroxyphenylpyruvic_acid dbr:Cyanobiont dbr:Laguna_Negra,_Catamarca dbr:Biological_pigment |
| is foaf:primaryTopic of | wikipedia-en:Scytonemin |
