''Penicillium roqueforti'' is a common

saprotrophic Saprotrophic nutrition or lysotrophic nutrition is a process of chemoheterotrophic extracellular digestion involved in the processing of decayed (dead or waste) organic matter. It occurs in saprotrophs, and is most often associated with fungi (f ...

fungus A fungus ( : fungi or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, separately from th ...

in the

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

Penicillium ''Penicillium'' () is a genus of ascomycetous fungi that is part of the mycobiome of many species and is of major importance in the natural environment, in food spoilage, and in food and drug production. Some members of the genus produce pe ...

''. Widespread in nature, it can be isolated from soil, decaying organic matter, and plants. The major industrial use of this fungus is the production of blue cheeses, flavouring agents, antifungals,

polysaccharide Polysaccharides (), or polycarbohydrates, are the most abundant carbohydrates found in food. They are long chain polymeric carbohydrates composed of monosaccharide units bound together by glycosidic linkages. This carbohydrate can react with wa ...

protease A protease (also called a peptidase, proteinase, or proteolytic enzyme) is an enzyme that catalyzes (increases reaction rate or "speeds up") proteolysis, breaking down proteins into smaller polypeptides or single amino acids, and spurring the ...

s, and other

enzyme Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrates, and the enzyme converts the substrates into different molecules known as products. A ...

s. The fungus has been a constituent of

Roquefort Roquefort is a sheep milk cheese from Southern France, and is one of the world's best known blue cheeses. Though similar cheeses are produced elsewhere, EU law dictates that only those cheeses aged in the natural Combalou caves of Roquefort-sur ...

Stilton Stilton is a village and civil parish in Cambridgeshire, England, about north of Huntingdon in Huntingdonshire, which is a non-metropolitan district of Cambridgeshire as well as a historic county of England. History There is evidence of Neo ...

Danish blue Danablu, often marketed under the trademark Danish Blue Cheese within North America, is a strong, blue-veined cheese. This semi-soft creamery cheese is typically drum- or block-shaped and has a yellowish, slightly moist, edible rind. Made from f ...

Cabrales Cabrales is a municipality in the autonomous community of Asturias, northwestern Spain. It is situated between the Sierra de Cuera and the Picos de Europa, and is a region famous for its Cabrales cheese. Important towns within the municipality ...

Gorgonzola Gorgonzola (; ) is a veined blue cheese, originally from Italy, made from unskimmed cow's milk. It can be buttery or firm, crumbly and quite salty, with a "bite" from its blue veining. History Historically, gorgonzola has been produced for ...

, and other blue cheeses. Other blue cheeses are made with ''

Penicillium glaucum ''Penicillium glaucum'' is a mold that is used in the making of some types of blue cheese, including Bleu de Gex, Rochebaron, and some varieties of Bleu d'Auvergne and Gorgonzola. (Other blue cheeses, including Bleu de Bresse, Bleu du Vercors- ...

''.

Classification

First described by American mycologist

Charles Thom Charles Thom (November 11, 1872 – May 24, 1956) was an American microbiologist and mycologist. Born and raised in Illinois, he received his PhD from the University of Missouri, the first such degree awarded by that institution. He was best k ...

in 1906, ''P. roqueforti'' was initially a heterogeneous species of blue-green, sporulating fungi. They were grouped into different species based on

phenotypic In genetics, the phenotype () is the set of observable characteristics or traits of an organism. The term covers the organism's morphology or physical form and structure, its developmental processes, its biochemical and physiological proper ...

differences, but later combined into one species by Kenneth B. Raper and Thom (1949). The ''P. roqueforti'' group got a reclassification in 1996 due to

molecular A molecule is a group of two or more atoms held together by attractive forces known as chemical bonds; depending on context, the term may or may not include ions which satisfy this criterion. In quantum physics, organic chemistry, and bioche ...

analysis of

ribosomal DNA Ribosomal DNA (rDNA) is a DNA sequence that codes for ribosomal RNA. These sequences regulate transcription initiation and amplification, and contain both transcribed and non-transcribed spacer segments. In the human genome there are 5 chromos ...

sequences. Formerly divided into two varieties―cheese-making (''P. roqueforti'' var. ''roqueforti'') and

patulin Patulin is an organic compound classified as a polyketide. It is a white powder soluble in acidic water and in organic solvents. It is a lactone that is heat-stable, so it is not destroyed by pasteurization or thermal denaturation.http://www.sig ...

-making (''P. roqueforti'' var. ''carneum'')―''P. roqueforti'' was reclassified into three species: ''P. roqueforti'', '' P. carneum'', and '' P. paneum''. The complete

genome sequence In the fields of molecular biology and genetics, a genome is all the genetic information of an organism. It consists of nucleotide sequences of DNA (or RNA in RNA viruses). The nuclear genome includes protein-coding genes and non-coding gen ...

of ''P. roqueforti'' was published in 2014.

Description

As this fungus does not form visible fruiting bodies, descriptions are based on macromorphological characteristics of fungal colonies growing on various standard agar media, and on microscopic characteristics. When grown on Czapek yeast autolysate agar or yeast-extract sucrose (YES) agar, ''P. roqueforti'' colonies are typically 40 mm in diameter, olive brown to dull green (dark green to black on the reverse side of the agar plate), with a velutinous texture. Grown on malt extract agar, colonies are 50 mm in diameter, dull green in color (beige to greyish green on the reverse side), with arachnoid (with many spider-web-like fibers) colony margins. Another characteristic morphological feature of this species is its production of asexual spores in phialides with a distinctive brush-shaped configuration. Evidence for a sexual stage in ''P. roqueforti'' has been found, based in part on the presence of functional mating-type genes and most of the important genes known to be involved in

meiosis Meiosis (; , since it is a reductional division) is a special type of cell division of germ cells in sexually-reproducing organisms that produces the gametes, such as sperm or egg cells. It involves two rounds of division that ultimately resu ...

. In 2014, researchers reported inducing the growth of sexual structures in ''P. roqueforti'', including ascogonia,

cleistothecia An ascocarp, or ascoma (), is the fruiting body ( sporocarp) of an ascomycete phylum fungus. It consists of very tightly interwoven hyphae and millions of embedded asci, each of which typically contains four to eight ascospores. Ascocarps are ...

, and

ascospore An ascus (; ) is the sexual spore-bearing cell produced in ascomycete fungi. Each ascus usually contains eight ascospores (or octad), produced by meiosis followed, in most species, by a mitotic cell division. However, asci in some genera or s ...

s. Genetic analysis and comparison of many different strains isolated from various environments around the world indicate that it is a genetically diverse species. ''P. roqueforti'' is known to be one of the most common spoilage molds of

silage Silage () is a type of fodder made from green foliage crops which have been preserved by fermentation to the point of acidification. It can be fed to cattle, sheep and other such ruminants (cud-chewing animals). The fermentation and storage p ...

. It is also one of several different moulds that can spoil bread.

Uses

The chief industrial use of this species is the production of blue cheeses, such as its namesake

Bleu de Bresse Bleu de Bresse () is a blue cheese that was first made in the Bresse area of France following World War II. Made from whole milk, it has a firm, edible coating which is characteristically white in color and has an aroma of mushrooms. Its creamy ...

Bleu du Vercors-Sassenage Bleu du Vercors-Sassenage is a mild pasteurized natural rind cow's milk blue cheese originally produced by monks in the Rhône-Alpes region of France in the 14th century. Now made in the Dauphiné area, the cheese has been a protected Appellation d ...

, Brebiblu,

Cambozola Cambozola is a cow's milk cheese that is a combination in style of a French soft-ripened triple cream cheese and Italian Gorgonzola. History Cambozola was patented and industrially produced for the world market by the large German company H ...

(Blue Brie),

Cashel Blue ''J&L Grubb'' is an List of Irish cheeses, Irish cheese manufacturer, making cows' milk and goats' milk cheeses on their farm near Fethard, South Tipperary. History In 1984, the Grubbs began to make around eight Cashel Blue cheeses at their farm ...

, Polish Rokpol made from cow's milk,

Fourme d'Ambert Fourme d'Ambert is a semi-hard French blue cheese. One of France's oldest cheeses, it dates from as far back as Roman times. It is made from raw cow's milk from the Auvergne region of France, with a distinct, narrow cylindrical shape. The semi-h ...

, Fourme de Montbrison, Lanark Blue, Shropshire Blue, and

, and some varieties of

Bleu d'Auvergne Bleu d'Auvergne () is a French blue cheese, named for its place of origin in the Auvergne region of south-central France. It is made from cow's milk, and is one of the cheeses granted the Appellation d'origine contrôlée from the French govern ...

and

. (Other blue cheeses, including

Bleu de Gex ''Bleu de Gex'' (also ''Bleu du Haut-Jura'' or ''Bleu de Septmoncel'') is a creamy, semi-soft blue cheese made from unpasteurized milk in the Jura region of France. It is named after the Pays de Gex, a historical region in what is now France a ...

and

Rochebaron Rochebaron is a soft blue cheese made from pasteurised cow's milk, in the town of Beauzac in the Auvergne region, in the Massif Central, France. This cheese is one of several that are made by curdling milk and separating the curds from the whey. ...

, use ''

''.) Strains of the microorganism are also used to produce compounds that can be employed as

antibiotic An antibiotic is a type of antimicrobial substance active against bacteria. It is the most important type of antibacterial agent for fighting bacterial infections, and antibiotic medications are widely used in the treatment and prevention of ...

s, flavours, and fragrances, uses not regulated under the U.S.

Toxic Substances Control Act The Toxic Substances Control Act (TSCA) is a United States law, passed by the 94th United States Congress in 1976 and administered by the United States Environmental Protection Agency (EPA), that regulates chemicals not regulated by other U.S. ...

. Its texture is

chitin Chitin ( C8 H13 O5 N)n ( ) is a long-chain polymer of ''N''-acetylglucosamine, an amide derivative of glucose. Chitin is probably the second most abundant polysaccharide in nature (behind only cellulose); an estimated 1 billion tons of chit ...

ous.

Secondary metabolites

Considerable evidence indicates that most strains are capable of producing harmful secondary metabolites (

alkaloid Alkaloids are a class of basic, naturally occurring organic compounds that contain at least one nitrogen atom. This group also includes some related compounds with neutral and even weakly acidic properties. Some synthetic compounds of similar ...

s and other

mycotoxin A mycotoxin (from the Greek μύκης , "fungus" and τοξίνη , "toxin") is a toxic secondary metabolite produced by organisms of kingdom Fungi and is capable of causing disease and death in both humans and other animals. The term 'mycotoxin' ...

s) under certain growth conditions.

Aristolochene Aristolochene is a bicyclic sesquiterpene produced by certain fungi including the cheese mold '' Penicillium roqueforti''. It is biosynthesized from farnesyl pyrophosphate by aristolochene synthase and is the parent hydrocarbon of a large vari ...

is a

sesquiterpenoid Sesquiterpenes are a class of terpenes that consist of three isoprene units and often have the molecular formula C15H24. Like monoterpenes, sesquiterpenes may be cyclic or contain rings, including many unique combinations. Biochemical modificati ...

compound produced by ''P. roqueforti'', and is likely a precursor to the toxin known as PR toxin, made in large amounts by the fungus.

PR-toxin Penicillin Roquefort Toxin (PR toxin) is a mycotoxin produced by the fungi ''Penicillium roqueforti''. In 1973, PR toxin was first partially characterized by isolating moldy corn on which the fungi had grown. Although its lethal dose was determined ...

has been implicated in incidents of mycotoxicoses resulting from eating contaminated grains. However, PR toxin is not stable in cheese and breaks down to the less toxic PR

imine In organic chemistry, an imine ( or ) is a functional group or organic compound containing a carbon–nitrogen double bond (). The nitrogen atom can be attached to a hydrogen or an organic group (R). The carbon atom has two additional single bo ...

Secondary metabolite Secondary metabolites, also called specialised metabolites, toxins, secondary products, or natural products, are organic compounds produced by any lifeform, e.g. bacteria, fungi, animals, or plants, which are not directly involved in the norm ...

s of ''P. roqueforti'', named andrastins A-D, are found in blue cheese. The andrastins inhibit proteins involved in the efflux of

anticancer drugs Chemotherapy (often abbreviated to chemo and sometimes CTX or CTx) is a type of cancer treatment that uses one or more anti-cancer drugs (chemotherapeutic agents or alkylating agents) as part of a standardized chemotherapy regimen. Chemotherap ...

from multidrug-resistant

cancer cell Cancer cells are cells that divide continually, forming solid tumors or flooding the blood with abnormal cells. Cell division is a normal process used by the body for growth and repair. A parent cell divides to form two daughter cells, and these d ...

s. ''P. roqueforti'' also produces the

neurotoxin Neurotoxins are toxins that are destructive to nerve tissue (causing neurotoxicity). Neurotoxins are an extensive class of exogenous chemical neurological insultsSpencer 2000 that can adversely affect function in both developing and mature ner ...

roquefortine C Roquefortine C is a mycotoxin that belongs to a class of naturally occurring 2,5-diketopiperazines produced by various fungi, particularly species from the genus ''Penicillium''. It was first isolated from a strain of ''Penicillium roqueforti'', a ...

. However, the levels of roquefortine c in cheese made from it is usually too low to produce toxic effects. The organism can also be used for the production of

s and specialty chemicals, such as

methyl In organic chemistry, a methyl group is an alkyl derived from methane, containing one carbon atom bonded to three hydrogen atoms, having chemical formula . In formulas, the group is often abbreviated as Me. This hydrocarbon group occurs in many ...

ketone In organic chemistry, a ketone is a functional group with the structure R–C(=O)–R', where R and R' can be a variety of carbon-containing substituents. Ketones contain a carbonyl group –C(=O)– (which contains a carbon-oxygen double bo ...

s, including 2-heptanone.

References

External links

:''This article is based on text originally fro
a report
of the

United States Environmental Protection Agency The Environmental Protection Agency (EPA) is an independent executive agency of the United States federal government tasked with environmental protection matters. President Richard Nixon proposed the establishment of EPA on July 9, 1970; it be ...

.'' {{Taxonbar, from=Q133247 roqueforti Molds used in food production Fungi described in 1906 Taxa named by Charles Thom