Mikrob.se

Penicillin / Penicillium chrysogenum

279 SEK

GiantMicrobes är mjukdjur som ser ut som små, små mikrober - bara det att de är förstorade sådär en miljon gånger. De ger bokstavligen ett ansikte åt förkylningen, fotsvampen, hostan, den dåliga andedräkten eller vägglusen. Varje GIGANTmicrobe är mellan ca 38-50 cm. Med följer ett foto på hur den riktiga mikroben ser ut samt en kort information på engelska.

Ursprungligen skapade i USA att användas i undervisningssyfte, har GIANTmicrobes nu blivit storsäljare i museishoppar, apotek, bokhandlar och designbutiker världen över.

GIANTmicrobes är ett roligt verktyg i undervisningen om hälsa och sjukdomar, men även en uppskattad gåva som passar alla åldrar. Definitivt roligare än ett krya-på-dig kort till en sjuk vän.

-------------


Penicillinet komer från denna lilla svamp Penicillum. En otrolig tillgång och livräddare i många många årtionden.

Så mycket som vi har att tacka honom för - borde alla ha en och krama i sängen :-)

.............

Meet the little blue fungus that could.

................

Penicillium chrysogenum

Från Wikipedia
Hoppa till: navigering, sök
SystematikDomänRikeStamKlassOrdningFamiljSläkteArtVetenskapligt namnAuktor
Penicillium chrysogenum
Penicillium chrysogenum
Penicillium chrysogenum
Eukaryoter
Eukaryota
Svampar
Fungi
Sporsäcksvampar
Ascomycota
Eurotiomycetes
Eurotiales
Trichocomaceae
'Penicillium'
P. chrysogenum
§ Penicillium chrysogenum
Thom

Penicillium chrysogenum är en mögelsvamp som är vitt spridd i naturen och kan ofta hittas i livsmedel och i inomhusmiljö [1] . Den kallades tidigare Penicillium notatum en art beskriven av den svenske farmakognosiprofessorn R.P. Westling. Det har sällan rapporterats som källa för sjukdomar hos människan. P. chrysogenum är en källa till flera antibiotika, den viktigaste penicillin G. Andra sekundära metaboliter inkluderar olika penicilliner, roquefortine C, meleagrin, chrysogine, xanthocillin, secalonsyra, sorrentanon, sorbicillin och PR-toxin.[2]

Historia[redigera | redigera wikitext]

P.chrysogenum användes av Egyptierna redan för tusentals år sedan, de använde den i medicinskt syfte som antibiotika. Mögelsvampen togs från bröd och gröt och intogs oralt. Alexander Fleming, en skotsk mikrobiologist, råkade av misstag återupptäcka mögelsvampens funktion 1928. Fleming åkte bort från labbet över helgen men försummade att städa upp sina bakterieexperiment med Staphylococcus aureus på en labbänk. När han återvände upptäckte han växande mögelsvampar i en av bakterieodlingarna. Han märkte också ett avstånd mellan mögelsvampskulturens kant och bakteriekulturen. Fleming försökte under lång tid återskapa experimentet, men utan framgång. Sommaren 1928 hade varit ovanligt kall, vilket Flemming inte tagit hänsyn till under sina försök att återskapa resultatet, vilket orsakade långsam tillväxt av både bakterier och svampar, vilket är nödvändigt för att kunna se den hämmande effekten. Det var hans kollega Ronald Hare, som lyckades återskapa resultaten genom att sänka temperaturen. Howard Walter Florey (1898-1968) och Ernst Boris Chain (1906-1979) var de forskare som mest framgångsrikt följde upp Alexander Flemings upptäckt av penicillin och delade med honom 1945 Nobelpriset i fysiologi och medicin.[3]

Uppbyggnad[redigera | redigera wikitext]

P. chrysogenum har en typisk cellstruktur för eukaryoter. Den har ett cellskelett av tubulin som används för motilitet och för stadga. Den har fyra kromosomer och kan även innehålla plasmider.

Ämnesomsättning[redigera | redigera wikitext]

P. chrysogenum är heterotrofa och foder av frukten de förstör. En intressant aspekt av metabolismen hos P. chrysogenum är att den uttrycker metabola gener differentiellt vid odling i olika medium. Förmånliga genuttryck stänger ner sekundära metaboliska vägar.

Sexuell förökning[redigera | redigera wikitext]

Kodidiosporer som gett P.chrysogenum sitt latinska namn.

P. chrysogenum reproducerar sig genom asexuella sporer (konidier) som släpps ut i miljön i en process som kallas groning. Efter groningen, sprids de haploida sporerna och reformerar till konidier genom mitos och därmed fortsätter cykeln. En enda asexuell spor kallas för en konidium och hänvisas också som en mitospor. Namnet Penicillium kommer från kondiosporernas liknande utseende till en pensel. Penicillus är latin för pensel. Konidiosporer utvecklas på

Konidiosporer. Konidiosporerna är grenade och består av multinucleata celler. På ändarna av grenarna i konidiosporena produceras de flaskliknande sterigmata. En sterigma (pl. sterigmata) är en förlängning av basidium (spor-bärande celler), som består av en filamentös del och en smal projektion med sporer vid spetsen. De är flerkärnbildande och bär konidier i kedjor. Varje konidial kedja har hundra eller fler konidier. Varje konidium är flerkärnbildande och grön, om konidier blir utspridda och får tillgång till lämplig föda och lämplig miljö för groning, gror de genom att producera rör som utvecklas till nya mycel. Sexuell reproduktion hos P. chrysogenum sker mycket sällan, om alls.

Ekologi[redigera | redigera wikitext]

P. chrysogenum är vanligast i naturen i fuktiga jordar med rikliga mängder kol och kväve för mykorrhiza tillväxt. Pencillium svampar är mångsidiga och opportunistiska. De är patogener som angriper efter skörd. Penicillium arter är en av de vanligaste orsakerna till svamp och förruttnelse i frukt och grönsaker.

Hur P. chrysogenum försvarar sig mot bakterier[redigera | redigera wikitext]

β-laktam-moleylen som är kärnan i ett flertal antibiotikum

P. chrysogenum producerar ett cellväggssynteshämmande molekyl, β-laktam, som är cidalt för bakterier och kallas även penicillin. Penicillinet är en inhibitor för bakteriens enzym som bygger upp bakteriens cellvägg av peptidoglykan som hålls samman av pentapeptidbryggor. Penicillinet förhindrar bildandets av pentapeptidbryggor, detta resulterar i bakteriens död då det vid celldelning inte produceras någon ny cellvägg. Grampositiva bakterier (G+) är i regel känsligare för penicillin än gramnegativa (G-), detta beror på de mycket olika uppbyggda strukturerna runt omkring bakterierna. G+-bakterier har en tjock cellvägg bestående av peptidoglykan (som kan vara uppemot 40 lager tjock) och innanför cellväggen finns cellmembranet. G--bakterier har ett yttre cellmembran delvis täckt av lipopolysackarider (som vårt imunförsvar är anpassat för att uppmärksamma) följt av ett periplasmiskt utrymme. I det periplasmiska utrymmet finns en tunn cellvägg av peptidoglykan. Innanför cellväggen finns ett inre cellmembran. Skillnaden mellan G+- och G--bakteriers uppbyggnad är det som avgör deras känslighet för penicillin. G--bakterier har en fysiskt mindre mängd cellvägg som dessutom är skyddad av ett yttre cellmembran medan G+-bakterier har en större och mer oskyddad mängd cellvägg.[4]

Bakteriers försvar mot P. chrysogenum[redigera | redigera wikitext]

Överanvändningen av olika bakteriehämmande substanser, Antibiotikum, har lett till en ökande resistens hos bakterier. Bakteriers resistens beror på enzymet β-laktamas (enzym) som klipper upp mögelsvampens β-laktam molekyler. Genen för att producera β-laktamas sitter i regel på bakteriers plasmider och kan därför föras över från bakterie till bakterie m.h.a. F-pili. Plasmiderna (med genen för β-laktamasproduktion) sprids genom horisontell spridning (från cell till cell). Mottagaren transformeras efter mottagandet till en penicillinresistent bakterie. Bakteriers resistens sprids även genom vertikal spridning d.v.s. från modercell till dottercell. I en miljö med penicillin utsätts populationen för ett selektivt/evolutionärt tryck. Spridningen sker då i hög takt främst vertikalt men även horisontellt. Detta är ett stort problem i sjukhusmiljö då patienter med redan utsatt imunförsvar blir utsatta för dessa svårbekämpade bakterier.[5][6]

Ekonomisk betydelse[redigera | redigera wikitext]

Penicillinsvampar förstör årligen stora mängder mat. Möbler och läder utsätts även i vissa fall för angrepp. Den största ekonomiska betydelsen av P. chrysogenum är dess förmåga att producera penicillin.

Referenser[redigera | redigera wikitext]

  1. ^ Samson RA, Hadlok R, Stolk AC (1977). ”A taxonomic study of the Penicillium chrysogenum series”. Antonie van Leeuwenhoek 43 (2): ss. 169–175. doi:10.1007/BF00395671. 
  2. ^ de Hoog GS, Guarro J, Gené J, Figueras F (2000), Atlas of Clinical Fungi - 2nd Edition, Centraalbureau voor Schimmelcultures (Utrecht) 
  3. ^  Jacob Christiansen, Anders Enevold, Lasse Foghsgaard, Anne Hansen, Gorm Palmgren, Stine Stentoft. Vetenskapens Universum. Medicinens Framsteg. Bonnier Publications A/S. 2009-07-31.
  4. ^ Dan Danielsson. Medicinsk mikrobiologi. Infektionsimunitet. Liber. 2002-10-01.
  5. ^ Elsy Ericson, Thomas Ericson. Klinisk mikrobiologi: Infektioner, Immunologi, Sjukvårdshygien. Liber AB. 1997-09-01
  6. ^ Jacquelyn G. Black. Microbiology: Principles and Explorations, 6th Edition. 6:e upplagan. 2005.

Externa länkar[redigera | redigera wikitext]

Mushroomsvg Denna svampartikel är bara påbörjad. Du kan hjälpa till genom att utöka den.
<img src="//sv.wikipedia.org/wiki/Special:CentralAutoLogin/start?type=1x1" alt="" title="" width="1" height="1" style="border: none; position: absolute;" />

Penicillium chrysogenum

From Wikipedia, the free encyclopedia
Jump to: navigation, search
Penicillium chrysogenumScientific classificationBinomial name
Penicillium chrysogenum
Kingdom:Fungi
Division:Ascomycota
Subdivision:Pezizomycotina
Class:Eurotiomycetes
Order:Eurotiales
Family:Trichocomaceae
Genus:Penicillium
Species:P. chrysogenum
Penicillium chrysogenum
Thom (1910)

Penicillium chrysogenum is a fungus, common in temperate and subtropical regions and can be found on salted food products,[1] but it is mostly found in indoor environments, especially in damp or waterdamaged buildings.[2] It was previously known as Penicillium notatum.[3] It has rarely been reported as a cause of human disease. It is the source of several β-lactam antibiotics, most significantly penicillin. Other secondary metabolites of P. chrysogenum include various penicillins, roquefortine C, meleagrin, chrysogine, xanthocillins, secalonic acids, sorrentanone, sorbicillin, and PR-toxin.[4]

Like the many other species of the genus Penicillium, P. chrysogenum usually reproduces by forming dry chains of spores (or conidia) from brush-shaped conidiophores. The conidia are typically carried by air currents to new colonisation sites. In P. chrysogenum the conidia are blue to blue-green, and the mold sometimes exudes a yellow pigment. However, P. chrysogenum cannot be identified based on colour alone. Observations of morphology and microscopic features are needed to confirm its identity and DNA sequencing is essential to distinguish it from closely related species such as Penicillium rubens. The sexual stage of P. chrysogenum was discovered in 2013 by mating cultures in the dark on oatmeal agar supplemented with biotin, after the mating types (MAT1-1 or MAT1-2) of the strains had been determined using PCR amplification.[5]

The airborne asexual spores of P. chrysogenum are important human allergens. Vacuolar and alkaline serine proteases have been implicated as the major allergenic proteins.[6]

P. chrysogenum has been used industrially to produce penicillin and xanthocillin X, to treat pulp mill waste, and to produce the enzymes polyamine oxidase, phospho-gluconate dehydrogenase, and glucose oxidase.[4][7]

Science and history[edit]

Penicillin was discovered in 1928 when Alexander Fleming's lab assistant left a window open overnight and had mold spores cover his Staphylococcus bacterial specimens in a petri dish.[8][9] At first, Fleming was very irritated at the contamination, but, as he was about to throw the specimens away, he noticed something interesting. He looked under the microscope at the bacteria surrounding the blue-green mold and noticed that many were dead or dying. This later turned out to have been due to the mold's prevention of the bacteria from making new cell walls and reproducing. He identified the mold as Penicillium notatum, which releases the antibiotic penicillin G into the medium. (This identification has been subsequently shown to be incorrect: the fungal species was actually Penicillium rubens).[10] After this, he did some testing on humans and animals and discovered that not only did it kill bacteria but it was suitable for use in humans and animals. However, the discovery did not attract much attention until the 1940s, when Howard Florey, Norman Heatley, and Ernst Chain developed methods for mass production and application in humans, incited by the urgent war-time need for antibacterial agents. The work of Andrew J. Moyer was important in these early developments.

At this point, though the drug had shown success in treating numerous bacterial diseases, it was still so difficult to produce and so dilute that it was not feasible to produce quantities large enough for mass production, and so an effort was begun to find a strain of Penicillium with a higher rate of production of penicillin. Army pilots sent back soil from around the world to be tested for the right kind of mold.[citation needed] Even the people of Peoria, Illinois were told to bring in any molds that they found around their homes.[citation needed] It has also been said[where?] that the scientists working on this project kept an eye out for similar-looking molds while grocery shopping or when they were cleaning around the kitchen especially their refrigerators.[citation needed]

It was by these means that Penicillium chrysogenum was discovered, on a cantaloupe from a grocery store in Peoria, Illinois.[11] The fungus isolated from this cantaloupe produced several hundred times as much penicillin as Fleming's original cultures of Penicillium notatum. Subcultures of this fungus were then irradiated with X-rays and UV rays in an attempt to cause a mutation in the fungus that would lead to an increase in penicillin yield. The effort was successful, and a mutant strain that yielded more than a thousand times the penicillin of Fleming's original culture was produced and cultured.[citation needed] This discovery, in combination with vastly improved methods of culturing the fungus based on the principle of aerating the culture medium, resulted in the ability to mass-produce penicillin in quantities great enough for distribution and mass use in the United States Army, and later within the British armed service and hospitals, in WWII.

The discovery of penicillin ushered in a new age of antibiotics derived from microorganisms. Penicillin is an antibiotic made by growing the mold Penicillium chrysogenum in a fermenter. The mold is grown in a liquid culture containing sugar and other nutrients including a source of nitrogen. As the mold grows, the sugar is used up and starts to make penicillin only after using up most of the nutrients for growth.

Genetics and evolution[edit]

The ability to produce penicillin appears to have evolved over thousands of years, and is shared with several other related fungi. It is believed to confer a selective advantage during competition with bacteria for food sources.[citation needed] However, some bacteria have developed the ability to survive penicillin exposure by producing penicillinases, enzymes that degrade penicillin.[citation needed] Penicillinase production is one mechanism by which bacteria can become penicillin resistant.

The principal genes responsible for producing penicillin, pcbAB, pcbC and penDE are closely linked, forming a cluster on chromosome I.[12] Some high-producing Penicillium chrysogenum strains used for the industrial production of penicillin have been shown to have multiple tandem copies of the penicillin gene cluster.[13]

References[edit]

  1. Jump up ^ Samson RA, Houbraken J, Thrane U, Frisvad JC & Andersen B. (2010). Food and Indoor Fungi. CBS-KNAW- Fungal Biodiversity Centre, Utrecht, the Netherlands. pp. 1-398.
  2. Jump up ^ Andersen B, Frisvad JC, Søndergaard I, Rasmussen IS & Larsen LS. 2011. Associations between fungal species and water damaged building materials. Applied and Environmental Microbiology. In Press
  3. Jump up ^ Samson RA, Hadlok R, Stolk AC (1977). "A taxonomic study of the Penicillium chrysogenum series". Antonie van Leeuwenhoek 43 (2): 169–175. doi:10.1007/BF00395671. PMID 413477
  4. ^ Jump up to: a b de Hoog GS, Guarro J, Gené J, Figueras F (2000), Atlas of Clinical Fungi - 2nd Edition, Centraalbureau voor Schimmelcultures (Utrecht) 
  5. Jump up ^ Böhm J, Hoff B, O’Gorman CM, Wolfers S, Klix V, Binger B, Zadra I, Kürnsteiner H, Pöggeler S, Dyer PS, Kückde U (2013), "Sexual reproduction and mating-type–mediated strain development in the penicillin-producing fungus Penicillium chrysogenum", Proc. Natl. Acad. Sci. U.S.A., PNAS Early Edition, doi:10.1073/pnas.1217943110 
  6. Jump up ^ Shen HD, Chou H, Tam MF, Chang CY, Lai HY, Wang SR (2003). "Molecular and immunological characterization of Pen ch 18, the vacuolar serine protease major allergen of Penicillium chrysogenum". Allergy 58 (10): 993–1002. doi:10.1034/j.1398-9995.2003.00107.x. PMID 14510716
  7. Jump up ^ Raper KB, Thom C (1949), A manual of the Penicillia, Williams & Wilkins Company (Baltimore) 
  8. Jump up ^ Diggins F (1999). "The true history of the discovery of penicillin, with refutation of the misinformation in the literature". Br J Biomed Sci 56 (2): 83–93. PMID 10695047
  9. Jump up ^ Ligon B (2004). "Penicillin: its discovery and early development". Semin Pediatr Infect Dis 15 (1): 52–7. doi:10.1053/j.spid.2004.02.001. PMID 15175995
  10. Jump up ^ Houbraken J, Frisvad JC, Samson RA (2011) Fleming's penicillin producing strain is not Penicillium chrysogenum but P. rubens. IMA Fungus 2(1):87-95
  11. Jump up ^ http://www.ars.usda.gov/is/timeline/penicillin.htm
  12. Jump up ^ Martín JF, Gutiérrez S, Fernández FJ, et al. (1994). "Expression of genes and processing of enzymes for the biosynthesis of penicillins and cephalosporins". Antonie Van Leeuwenhoek 65 (3): 227–243. doi:10.1007/BF00871951. PMID 7847890
  13. Jump up ^ Fierro F, Barredo JL, Díez B, Gutierrez S, Fernández FJ, Martín JF (1995). "The penicillin gene cluster is amplified in tandem repeats linked by conserved hexanucleotide sequences". Proc. Natl. Acad. Sci. U.S.A. 92 (13): 6200–6204. doi:10.1073/pnas.92.13.6200. PMC 41670. PMID 7597101

External links[edit]

<img src="//en.wikipedia.org/wiki/Special:CentralAutoLogin/start?type=1x1" alt="" title="" width="1" height="1" style="border: none; position: absolute;" />

Penicillium

From MicrobeWiki, the student-edited microbiology resource

Jump to: navigation, search
This is a curated page. Report corrections to Microbewiki.

A Microbial Biorealm page on the genus Penicillium

Penicillium italicum and Penicillium digitatum growing on an orange. by George Barron

Contents

 [hide

Classification

Higher order taxa

Eukaryota; Fungi/Metazoa group; Fungi; Ascomycota; Pezizomycotina; Eurotiomycetes; Eurotiales; Trichocomaceae; mitosporic Trichocomaceae

Species

Penicillium notatum
Penicillium chrysogenum
Penicillium roquefortii

NCBI: Taxonomy Genome

Description and Significance

Bleu cheese made from Penicillium roquefortii. The Fungus Among Us

Penicillium are comparable to Aspergillus. The genus Penicillium falls into the order Eurotiales. In this order, organisms produce asci within cleistothecia. Penicillium is often reffered to as Deuteromycetes, or Fungi imperfecti. The name Penicillium comes from the word "brush"; this refers to the appearance of spores in Penicillium.

One species, Penicillium chrysogenum 9', is classified as a psychrotrophic microorganism. Bancerz et. al. (2005) found that this species was one of the best lipase producers among other fungi they studied in the arctic tundra. Penicillium chrysogenum has high enzymatic activity and has the ability to produce alpha-amylase.

Genome Structure

Most fungi contain secondary metabolites. These are often used to create antibiotics such as penicillin. Certain components of fungal genetic strucutre that create these secondary metabolites are common across not just species, but across orders. The genetic structures that make up these secondary metabolites are often very complex. Carlile et. al. (2001) cite an example in which of 11 amino acids in cyclosporin, only two were found in protiens. It is believed that genes encoding some of the enzymes are found in clusters on a single chromosome. Evidence for this has been found in Penicillium chrysogenum, among other organisms. The location of these genes suggests that the individual chromosome may play a role in expression of these genes. Ribon et. al. (2001) found that endopolygalacturonase-coding genes exist as single copies on the fungus genome in Penicillium griseoroseum. They also found that P. griseoroseum has a similar hybridization pattern to P. expansum, P. italicum, and P. purpurogenum. This suggests that the genes in these species have simlar global organization in their particular genome segment.

Cell Structure and Metabolism

A conidiophore from a Penicillium mold.
Numbered ticks are 20 µM apart.
Photograph by Bob Blaylock

With the exception of Penicillium marneffei, which is thermally dimorphic, Penicillium are filamentous fungi. They have branched conidiospores. Conidia are round and unicellular. Glucans are common in the cell walls of Penicillium species. Penicillium species tend to have small hyphae. This makes protoplasmic movement difficult to detect. The small hyphae also lead to smaller peripheral growth zones. Penicillium spores have a hydrophobic surface. However, they are capable of being wetted; this is necessary for germination to occur. Penicillium are osmotolerant, meaning that although they grow better with high water levels, they are able to tolerate low water potential.

Penicillium species are heterotrophic. The pathogenic species feed off of the fruit they destroy.

Penicillium produces asexually, and are unable to sporulate when submerged. However, they begin reproduction easily when hyphae emerge into a gas phase. No species has the exact same method of reproduction. Each is classified based on the way it reproduces. For example, in some species, conidia are borne on phialidies, which group out of the conidiophore. In others the conidiophore bears metullae, where phialidies are borne. Still in others the conidiophore may branch out before bearing metullae. Branching may or may not be symmetrical, depending on species. Sporulation is not stimulated by changes in oxygen, carbon dioxide, or water loss. Instead, it is associated with change in physical environment at the hyphal surface. There is no specific method for ascospore dispersal.

Ecology

Pencillium fungi are versatile and opportunistic. They are post-harvest pathogens. Penicillium species are one of the most common causes of fungal spoilage in fruits and vegetables. Penicillium italicum and Penicillium digitatum are the most common attackers of citrus fruits, while Penicillium expansum is known to attack apples. P. digitatum works by producing ethylene to accelerate ripening. It the covers the fruit with green conidia, causing the fruit to shrivel and dry out. P. italicum causes slimy rot and produces blue-green conidia. These species like cooler temperatures, which explains why they are usually found on foods left too long in the refrigerator. Many species produce mycotoxins; for example, P. expansum produces one called patulin. Most of these species resemble each other in color characteristics, style of decay, and infection symptoms; they fall under a general category called blue mold. P. expansum is one of the most aggressive species. These fungi live a long time and are quite durable, even under adverse conditions. Sometimes, P. italicum and P. expansum will adhere to each other to create synnemata. Synnemata also occurs in Penicillum claviforme. Penicillium growth typically occurs as a result of wound infections in produce. The most common treatment is to use fungicide on harvested produce. Penicillium species attack more than just fruit. For example, Penicillium verrucosum grows on cereal products.

One species, Penicillium marneffei, is rare to most of the world. It is endemic to Southeast Asia and infects bamboo rats. It can be spread to humans, especially immunosuppressed individuals.

However, Penicillium is not merely a harmful fungus. It also has many useful species. For example, Penicillium roquefortii is used to make bleu cheese. The color of the cheese comes from the spores (conidia) of the fungus. The spores are injected into the cheese curd during fermentation. Penicillium camambertii is another species used to produce cheese.

Some Penicillium species actually help prevent fungal decay as opposed to producing it. Penicillium chrysogenum produces glucose oxidase, which is used as a preservative in fruit juices.

One of the things Penicillium is most famous for is the drug penicillin. It was used to create the first antibiotic. The originial strain, Penicillium notatum, was discovered in 1920 by Sir Alexander Fleming. However, it was replaced with Penicillium chrysogenum, a more productive species, which is now the species used in manufacturing penicillin.