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Information about Mold

This article is about the fungi known as molds. Slime molds and water molds are not fungi and are discussed in separate articles. For other uses, see Mold (disambiguation).


Molds (or moulds, see spelling differences) include all species of microscopic fungi that grow in the form of multicellular filaments, called hyphae.[1] In contrast, microscopic fungi that grow as single cells are called yeasts. A connected network of these tubular branching hyphae has the same DNA and is considered a single organism, referred to as a colony or in more technical terms a mycelium.

Molds do not form a specific taxonomic or phylogenetic grouping, but can be found in the divisions Zygomycota, Deuteromycota and Ascomycota. Although some molds cause disease or food spoilage, others are useful for their role in biodegradation or in the production of various foods, beverages, antibiotics and enzymes.

Biology

Mold covering a decaying peach over a period of six days. The frames were taken approximately 12 hours apart. There are 12 frames of changes.
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Moldy nectarines that were in a refrigerator. The nectarine with black mold is also affecting the nectarine underneath.


There are thousands of known species of molds, which include opportunistic pathogens, exclusive saprotrophs, aquatic species and thermophiles.[2] Like all fungi, molds derive energy not through photosynthesis but from the organic matter on which they live. Typically, molds secrete hydrolytic enzymes from predominantly the hyphal tips. These enzymes degrade complex biopolymers such as starch, cellulose and lignin into simpler substances which can enter the hyphae. In this way, molds play a major role in causing decomposition of organic material, enabling the recycling of nutrients throughout ecosystems. Many molds also secrete mycotoxins which, together with hydrolytic enzymes, inhibit the growth of competing microorganisms.

Molds reproduce through small spores.[2] Mold spores can be asexual (the products of mitosis) or sexual (the products of meiosis), and many species can produce both types. They may contain a single nucleus or many. Some can remain airborne indefinitely, and many are able to survive extremes of temperature and pressure.

Although molds grow on dead organic matter everywhere in nature, their presence is only visible to the unaided eye when mold colonies grow. A mold colony does not comprise discrete organisms, but an interconnected network of hyphae called a mycelium. Nutrients and in some cases organelles may be transported throughout the mycelium. In artificial environments like buildings, humidity and temperature are often stable enough to foster the growth of mold colonies, commonly seen as a downy or furry coating growing on food or surfaces.

Some mold can begin growing at temperatures as low as 2°C. When conditions do not enable growth, molds can remain alive in a dormant state, within a large range of temperatures before they die. This explains how molds can survive harsh conditions such as containers in refrigerators or inside building structure cavities.

Xerophilic molds use the humidity in the air as their only water source; other molds need more moisture.

Common molds

Uses

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Stilton cheese contains edible mold.

Food production

Cultured molds are used in the production of foods including cheese (Penicillium spp), tempeh (Rhizopus oligosporus), quorn (Fusarium venenatum), the black tea pu-erh and some sausages.

The koji molds are a group of Aspergillus species, notably Aspergillus oryzae, that have been cultured in eastern Asia for many centuries. They are used to ferment a soybean and wheat mixture to make soybean paste and soy sauce. They are also used to break down the starch in rice (saccharification) in the production of sake and other distilled spirits.

Drug creation

Alexander Fleming's famous discovery of the antibiotic penicillin involved the mold Penicillium notatum.

Other Uses

Other molds are cultivated for their ability to produce useful substances. Aspergillus niger is used in the production of citric acid, gluconic acid and many other compounds and enzymes.

The molds Neurospora crassa and Aspergillus nidulans are commonly used model organisms.

Health effects

Main article: Mold health issues


Mold spores can be allergenic, causing irritations of eye, nose, throat, and lungs.

Molds excrete liquids or gases as defecatory matter; not all can be detected by smell. Some molds generate toxic liquid or gaseous compounds, called mycotoxins. Molds that produce mycotoxins are sometimes referred to as toxic molds. Of these molds, some only produce mycotoxins under specific growing conditions. Mycotoxins are harmful or lethal to humans and animals when exposure is high enough.

Dermatophytes are the parasitic fungi that cause skin infections such as Athlete's foot and Jock Itch. Most dermataphyte fungi take the form of a mold, as opposed to a yeast, with appearance (when cultured) that is similar to other molds.

Infection by opportunistic pathogen molds such as Penicillium marneffei and Aspergillus fumigatus is a common cause of death among immunocompromised people, including AIDS patients.

Growth in buildings

Main articles: Mold growth, assessment, and remediation and Indoor air quality


Mold growth in buildings can lead to variety of health issues. Various practices can be followed to mitigate mold growth in buildings.

See also

References

1. ^ Madigan M; Martinko J (editors). (2005). Brock Biology of Microorganisms, 11th ed., Prentice Hall. ISBN 0131443291. 
2. ^ Ryan KJ; Ray CG (editors) (2004). Sherris Medical Microbiology, 4th ed., McGraw Hill, pp. 633–8. ISBN 0838585299. 
Mycetozoa

Typical orders

Protostelia
Protosteliida
Myxogastria
Liceida
Echinosteliida
Trichiida
Stemonitida
Physarida

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Oomycetes

Orders

Lagenidiales
Leptomitales
Peronosporales
Rhipidiales
Saprolegniales
Sclerosporales
Water molds (or water moulds: see spelling differences) also known as Oomycetes
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Mold or mould (see spelling differences) is used most to refer to certain organisms:
  • Mold or mould, a kind of fungus
  • Slime moulds, kinds of protist
  • Water mould, kinds of protist

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American and British English spelling differences are one aspect of American and British English differences.

In the early 18th century, English spelling was not standardised. Different standards became noticeable after the publishing of influential dictionaries.
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Eukarya
Whittaker & Margulis, 1978
(unranked) Opisthokonta

Kingdom: Fungi
(L., 1753) R.T. Moore, 1980[1]

Subkingdom/Phyla

Chytridiomycota
Blastocladiomycota

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Multicellular organisms are organisms consisting of more than one cell, and having differentiated cells that perform specialized functions. Most life that can be seen with the naked eye is multicellular, as are all members of the kingdoms Plantae and Animalia (except for
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A hypha (plural hyphae) is a long, branching filamentous cell of a fungus, and also of unrelated Actinobacteria.[1] In fungi, hyphae are the main mode of vegetative growth, and are collectively called a mycelium.
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Ascomycota (sac fungi)
  • Saccharomycotina (true yeasts)
  • Taphrinomycotina
  • Schizosaccharomycetes (fission yeasts)
Basidiomycota (club fungi)
  • Urediniomycetes

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A hypha (plural hyphae) is a long, branching filamentous cell of a fungus, and also of unrelated Actinobacteria.[1] In fungi, hyphae are the main mode of vegetative growth, and are collectively called a mycelium.
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colony is a territory under the immediate political control of a state. For colonies in antiquity, city-states would often found their own colonies. Some colonies were historically countries, while others were territories without definite statehood from their inception.
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Mycelium is the vegetative part of a fungus, consisting of a mass of branching, thread-like hyphae. The mass of hyphae is sometimes called shiro, especially within the fairy ring fungi. Fungal colonies composed of mycelia are found in soil and on or in many other substrates.
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For the science of classifying living things, see .


Taxonomy is the practice and science of classification. The word comes from the Greek τάξις, taxis, 'order' +
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phylogenetics (Greek: phyle = tribe, race and genetikos = relative to birth, from genesis = birth) is the study of evolutionary relatedness among various groups of organisms (e.g., species, populations).
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Zygomycota
Moreau 1954 (technically invalid)

Class: Zygomycetes

Orders
Dimargaritales
Endogonales
Entomophthorales
Harpellales
Kickxellales
Microsporidia
Mucorales
Zoopagales

Zygomycota
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Deuteromycota (Greek for "second fungi") were once considered a formal phylum of the kingdom Fungi. The term is now used only informally, to denote species of fungi that are asexually reproducing members of the fungal phyla Ascomycota and Basidiomycota.
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Decomposition (or spoilage) refers to the reduction of the body of a formerly living organism into simpler forms of matter.

Plant decomposition

See also:  and

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Biodegradation is the process by which organic substances are broken down by living organisms. The term is often used in relation to ecology, waste management, environmental remediation (bioremediation) and to plastic materials, due to their long life span.
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antibiotic is a chemotherapeutic agent that inhibits or abolishes the growth of micro-organisms, such as bacteria, fungi, or protozoans. The term originally referred to any agent with biological activity against living organisms; however, "antibiotic" now is used to refer to
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Enzymes are proteins that catalyze (i.e. accelerate) chemical reactions.[1] In enzymatic reactions, the molecules at the beginning of the process are called substrates, and the enzyme converts them into different molecules, the products.
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Opportunistic infections are infections caused by organisms that usually do not cause disease in a person with a healthy immune system, but can affect people with a poorly functioning or suppressed immune system. They need an "opportunity" to infect a person.
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A saprotroph (or saprobe) is an organism that obtains its nutrients from non-living organic matter, usually dead and decaying plant or animal matter, by absorbing soluble organic compounds.
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thermophile is an organism – a type of extremophile – which thrives at relatively high temperatures, above 45 °C. Many thermophiles are archaea.

Thermophiles are found in various geothermally heated regions of the Earth such as hot springs like those in
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Other meanings can be found at Biological material


Organic matter (or organic material) is matter that has come from a recently living organism; is capable of decay, or the product of decay; or is composed of organic compounds.
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Enzymes are proteins that catalyze (i.e. accelerate) chemical reactions.[1] In enzymatic reactions, the molecules at the beginning of the process are called substrates, and the enzyme converts them into different molecules, the products.
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Biopolymers are a class of polymers produced by living organisms. Starch, proteins and peptides, DNA, and RNA are all examples of biopolymers, in which the monomer units, respectively, are sugars, amino acids, and nucleic acids.
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Starch (CAS# 9005-25-8, chemical formula (C6H10O5)n,[1]) is a mixture of amylose and amylopectin (usually in 20:80 or 30:70 ratios).
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Cellulose is an organic compound with the formula (C6H10O5)n. It is a structural polysaccharide derived from beta-glucose.[1][2] Cellulose is the primary structural component of green plants.
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