Penicillium chrysogenum

from Wikipedia, the free encyclopedia
Penicillium chrysogenum
Penicillium notatum.jpg

Penicillium chrysogenum

Systematics
Class : Eurotiomycetes
Subclass : Eurotiomycetidae
Order : Eurotiales
Family : Trichocomaceae
Genre : Brush mold ( Penicillium )
Type : Penicillium chrysogenum
Scientific name
Penicillium chrysogenum
Thom

Penicillium chrysogenum (synonym Penicillium notatum ) is a type of mold from the genus of brush mold ( Penicillium ). It is a globally distributed saprobiont that lives mainly in dead, decomposing, organic matter and has a significant share in the material cycle inthe earth's ecosystems . The species became known primarily through the discovery of penicillin from Penicillium chrysogenum by Alexander Fleming in 1928. Today the species is used for industrial penicillin production. Penicillium chrysogenum grows widely on spoiled food and can cause allergies in humans.

sexuality

Brush mold ( Penicillium ) have a pleomorphic development cycle ; they have a sexual form ( teleomorph ) and an asexual form ( anamorph ). Many species, such as Penicillium chrysogenum , belong to the so-called Fungi imperfecti , which means that it is not known whether they reproduce exclusively asexually or whether the phase of sexual reproduction has not yet been discovered. Only the asexual forms are as Penicillium called, at best known sexual forms get a different genus name, then in the usual scheme of the sac fungi (Ascomycota) in the family of Trichocomaceae is classified.

Of Penicillium chrysogenum no sexual form is known. The following description therefore refers exclusively to the anamorphic.

description

Penicillium chrysogenum initially form yellow-green, but with age, darkening to green tones, then turning to dark green, dark blue-green or dark-green-violet, which grow in so-called colonies . However, the colonies of some strains are also mineral gray. The surface of these colonies is usually velvety, but sometimes also fur-like with ring-shaped warps. The edge is often lobed, the surface of some trunks thinly overgrown hyaline . The colonies initially consist of a dense network of hyphae called the mycelium . Some strains produce a yellowish, purple, or colorless exudate . The mushroom lawn smells aromatic, fruity or hot, but some stems are also described as odorless.

During fructification , brush-like conidia carriers are formed, which are used for reproduction and on which conidiospores (conidia) mature. The conidiophores consist of a branched conidiophore and phialides . The term conidiophore is used inconsistently, however, and is occasionally used synonymously with the entire conidium carrier.

The conidiophore is almost cylindrical, grows perpendicular to the mycelium and branches out in three, in some trunks in four stages. It is mononematous, i.e. separated from the hyphae cells. It is between 400 and 1,000 micrometers high and between 2.0 and 2.3 micrometers in diameter. The wall is smooth and hyaline. At the tip an inconspicuous, cylindrical metula develops , which is between 8 and 15 micrometers high and not wider than the conidiophore. From it 3 to 6 phialides arise.

The phialides are bottle-like with a short cylindrical neck that thickens towards the top. They measure 7 to 10 micrometers in length and 2.0 to 2.5 micrometers in diameter. The conidia are initially almost spherical to ellipsoid, but then develop into a perfect spherical shape. They are smooth-walled and hyaline or slightly greenish. They measure 3.0-4.0 × 2.8-3.8 micrometers and are in chains.

distribution

In order to grow, Penicillium chrysogenum needs a minimum temperature of 4 ° C, an ambient temperature of 23 ° C is optimal. The maximum temperature at which growth was still observed is 37 ° C. Penicillium chrysogenum is therefore psychrotolerant . The species is ubiquitous. It can be found in the soil, on fruits in food and as spores in the air. However, it prefers to thrive in moist soil, where it acts as a saprobiont to decompose dead plant parts.

Penicillium chrysogenum is cosmopolitan , which means that the species can be found almost everywhere on earth. It has even been found in the subglacial ice below arctic glaciers.

genetics

The genome of Penicillium chrysogenum is approximately 34.1 megabase pairs in a wild type . The DNA in the cell nucleus is distributed over four chromosomes : 1, 2, 3 and 4 with 10.4, 9.6, 7.6 and 6.3 Mbp respectively. The economically important penicillin gene cluster is here on chromosome 1; in Penicillium notatum (32.1 Mbp) it is on the second chromosome. The genome sizes of industrially used strain lines of P. chrysogenum differ slightly.

The species was fully sequenced in 2008 . Around 57% of the DNA in the nucleus encodes around 13,000 genes for proteins. Under the conditions for the production of high amounts of penicillin G , expression is increased in about 300 of these genes and decreased in almost as many. The nuclear DNA of the genome is around a thousand times larger than mitochondrial DNA, which is 31,790 base pairs .

use

Penicillium chrysogenum is an important producer of β-lactam antibiotics , especially penicillin . Today this is obtained industrially in bioreactors .

Discovery of penicillin

In 1928, Alexander Fleming , who was involved with staphylococci , had inoculated an agar plate with staphylococci and then set it aside before his vacation . On his return on September 28, 1928, he discovered that a mold ( Penicillium notatum ) had grown on the nutrient medium and that the bacteria had not multiplied in the vicinity of the fungus.

Fleming was able to isolate the bactericidal substance from the culture medium and named it penicillin .

Fleming did not yet use the newly discovered penicillin as a drug. This was achieved in 1938 by Howard Walter Florey , Ernst Boris Chain and Norman Heatley . In 1942, Hans Knöll realized the first large-scale penicillin production in Jena on the European mainland.

Pathogenicity

The ability of Penicillium chrysogenum to live on many different substrates under a wide range of environmental conditions means that some species can also grow on living or dead tissues of humans or animals. The infestation of living tissue is the cause of various diseases. However, such an infestation is always accidental, since all Penicillium species are actually saprobionts. In addition to the direct infestation of tissue, Penicillium chrysogenum produces some toxic or allergenic secondary metabolites .

Infections

Microscope image of a histological section showing a P. Chrysogenum infection with incipient angioinvasion

Penicillium chrysogenum infections are very rare. When they occur, only immunocompromised patients, for example after a bone marrow or stem cell transplant, or AIDS patients, are affected. In such patients, lung infections, similar to aspergillosis , can occur in particular . Since Penicillium chrysogenum infections are very rare, they are usually confused with Aspergillus infections at first . Infections of the eye can occur even more rarely.

Allergies

In addition, Penicillium chrysogenum can trigger allergies or promote asthma . The protein Pen ch 13 ( oryzine , a serine protease ) is an active allergen that can trigger a histamine response; Oryzin is cross-allergenic in several types of mold. Another common allergen is Pen Ch 35 , the transaldolase of the fungus, with cross-allergenicity in Cladosporium species.

Mycotoxins

Structural formula of secalonic acid D

Penicillium chrysogenum very often grows on foods and releases secondary metabolites to them, including poisonous mycotoxins . The most frequently infected foods include grain products, but also fruit, especially grapes, are regularly infected. Practically all foods are regularly covered with Penicillium chrysogenum .

The secondary metabolites released include:

Even if, for example, Roquefortin C can be neurotoxic , Penicillium chrysogenum is not a serious source of mycotoxins in food.

Systematics

The species Penicillium chrysogenum is very variable, different strains can show considerable morphological variations. For this reason, the species used to be divided into different species that formed a series . In 1977, Samson et al. but these species become a single species. For this reason, Penicillium chrysogenum has a large number of synonyms . The most important are Penicillium notatum and Penicillium meleagrinum .

Within the genus, the species is classified in the section Asymmetrica, subsection Velutina . The species around Penicillium oxalicum are morphologically most similar . Penicillium chrysogenum is probably derived from lichen- forming fungi, but has lost this ability.

swell

Unless otherwise stated, the information in the Description section is taken from the sources: Raper & Thom 1949 and Samson et al. 1977. Pitt & Hocking 2009 was the main source for the chapter on mycotoxins, unless otherwise stated.

literature

  • Kenneth B. Raper, Charles Thom: A Manual of the Penicillia . Williams & Wilkins, Baltimore 1949, pp. 359-364 (English).
  • RA Samson, R. Hadlok, Amelia C. Stolk: A taxonomic study of the Penicillium chrysogenum series . In: Antonie van Leeuwenhoek . tape 43 , no. 2 , 1977, p. 169–175 , doi : 10.1007 / BF00395671 (English).
  • John I. Pitt, Ailsa D. Hocking: Fungi and Food Spoilage . 3. Edition. Springer, Dordrecht 2009, ISBN 978-0-387-92206-5 , pp. 235–237 ( online in Google Book Search).

Web pages

  • V. Robert, G. Stegehuis, J. Stalpers: Penicillium chrysogenum. In: The MycoBank engine and related databases. Retrieved August 17, 2011 .

Individual evidence

  1. ^ Jens Nielsen: Physiological engineering aspects of Penicillium chrysogenum . World Scientific, Singapore 1996, ISBN 978-981-02-2765-4 , pp. 184 ( online in Google book search).
  2. ^ Pitt & Hocking, 2009
  3. ↑ D. Macocinschi, D. Filip, C. Tanase, S. Vlad, A. Oprea, T. Balaes: The relationship of some polyurethane biocomposites against Penicillium chrysogenum and Aspergillus brasiliensis . In: Optoelectronics and Advanced Materials - Rapid Communications . tape 6 , no. 6 , June 2011, p. 677-681 (English, pdf ).
  4. ↑ Silva Sonjak, Jens C. Frisvad, Nina Gunde-Cimerman: Penicillium Mycobiota in Arctic Subglacial Ice . In: Microbial Ecology . tape 52 , no. 2 , August 2006, p. 207-216 , JSTOR : 25153372 (English).
  5. ↑ Francisco Fierro, Santiago Gutiérrez, Bruno Diez, Juan F. Martín: Resolution of four large chromosomes in penicillin-producing filamentous fungi: the penicillin gene cluster is located on chromosome II (9.6 Mb) in Penicillium notatum and chromosome 1 (10.4 Mb) in Penicillium chrysogenum . In: Molecular and General Genetics . tape 241 , no. 5-6 , December 1993, pp. 573-578 , doi : 10.1007 / BF00279899 (English).
  6. ↑ Zhanyou Xu, Marco A. van den Berg, Chantel Scheuring, Lina Covaleda, Hong Lu, Felipe A. Santos, Taesik Uhm, Mi-Kyung Lee, Chengcang Wu, Steve Liu, Hong-Bin Zhang: Genome physical mapping from large- insert clones by fingerprint analysis with capillary electrophoresis: a robust physical map of Penicillium chrysogenum . In: Nucleic Acids Research . tape 33 , no. 5 , February 2005, p. e50 , doi : 10.1093 / nar / gni037 (English).
  7. ↑ Marco A van den Berg, Richard Albang, Kaj Albermann u. a .: Genome sequencing and analysis of the filamentous fungus Penicillium chrysogenum . In: Nature Biotechnology . tape 26 , no. 10 , October 2008, p. 1161–1168 (English, pdf ).
  8. ↑ Alexander Fleming: On the antibacterial action of cultures of a penicillium, with special reference to their use in the isolation of B. influenzæ . In: British Journal of Experimental Pathology . tape 10 , no. 31 , 1929, pp. 226-236 (English).
  9. ^ Adrian L. Barcus, Steven D. Burdette, Thomas E. Herchline: Intestinal invasion and disseminated disease associated with Penicillium chrysogenum . In: Annals of Clinical Microbiology and Antimicrobials . tape 4 , no. December 21 , 2005, doi : 10.1186 / 1476-0711-4-21 (English).
  10. ^ Mary L. Eschete, John W. King, Burton C. West, Arnold Oberle: Penicillium chrysogenum endophthalmitis First reported case . In: Mycopathologia . tape 74 , no. 2 , May 1981, pp. 125-127 , doi : 10.1007 / BF01259468 (English).
  11. ↑ HY Tai, MF Tam, H. Chou, HJ Peng, SN Su, DW Perng, HD Shen: Pen ch 13 allergen induces secretion of mediators and degradation of occludin protein of human lung epithelial cells . In: Allergy . tape 61 , no. 3 , March 2006, p. 382-388 , PMID 16436150 (English).
  12. ↑ Allergome to Pen Ch 13
  13. ↑ H. Chou, MF Tam et al. a .: Transaldolases are novel and immunoglobulin E cross-reacting fungal allergens. In: Clinical and Experimental Allergy Volume 41, Number 5, May 2011, pp. 739-749. doi: 10.1111 / j.1365-2222.2011.03698.x . PMID 21488999 .
  14. ↑ Samson et al. 1977
  15. ↑ Kitzmann, 2008