Slime molds
Aethalium of a slime mold (Fuligo septica)
Scientific classification
Domain: Eukaryota Phylum: Amoebozoa Class: Mycetozoa
Typical orders
Protostelia Download high resolution version (800x757, 355 KB)Slime mold (?Fuligo sp. ... For other uses, see Scientific classification (disambiguation). ... Kingdoms Eukaryotes are organisms with complex cells, in which the genetic material is organized into membrane-bound nuclei. ... Subgroups Mycetozoa(slime moulds) Archamoebae    Pelobiontida    Entamoebida Gymnamoebia Various others The Amoebozoa are a major group of amoeboid protozoa, including the majority that move by means of internal cytoplasmic flow. ... Protosteliida Myxogastria Liceida Echinosteliida Trichiida Stemonitida Physarida Dictyostelia Dictyosteliida

Slime Molds (or Mycetozoa) is a broad term often referring to roughly six groups of Eukaryotes. The taxonomy is still in flux. Originally, they were considered Fungi, but now they have been split into various groups: Families & Genera Dictyosteliidae     Dictyostelium     Polysphondylium     Coenonia Actyosteliidae     Acytostelium The dictyostelids are a group of cellular slime moulds. ... Kingdoms Eukaryotes are organisms with complex cells, in which the genetic material is organized into membrane-bound nuclei. ... Divisions Chytridiomycota Zygomycota Ascomycota Basidiomycota The Fungi (singular: fungus) are a large group of organisms ranked as a kingdom within the Domain Eukaryota. ...

• Myxogastria/Myxomycetes: plasmodial or coenocytic slime molds.
• Protostelia : smaller plasmodial slime molds.
• Dictyosteliida : cellular slime molds.
• Acrasidae : similar life style to Dictyostelids, but of uncertain taxonomy.
• Plasmodiophorids : cabbage club root disease.
• Labyrinthulomycetes : slime nets.

The Myxogastria, Protosteli, and Dictyosteliida make up the group Mycetozoa. The mycetozoan groups all fit into the unikont supergroup Amoebozoa, whereas the others fit into various bikont groups. Slime molds feed on microorganisms in decaying vegetable matter. They can be found in the soil, on lawns, and in the forest commonly on deciduous logs. They are also common on mulch or even in leaf mold which collects in gutters. They begin life as amoeba-like cells. These unicellular amoebae are commonly haploid and multiply if they encounter their favorite food bacteria. These amoebae can mate if they encounter the correct mating type and form zygotes which then grow into plasmodia which contain many nuclei without cell membranes between them, which can become meters in size. One variety is often seen as a slimy yellow network in and on rotting logs. The amoebae and the plasmodia engulf microorganisms. The plasmodium grows into an interconnected network of protoplasmic strands. Within each protoplasmic strand the cytoplasmic contents rapidly stream. If one strand is carefully watched for about 30 seconds the cytoplasm can be seen to slow, stop, and then reverse direction. Migration of the plasmodium is accomplished when more protoplasm streams to advancing areas and protoplasm is withdrawn from rear areas. When the food supply wanes, the plasmodium will migrate to the surface of its substrate and transform into rigid fruiting bodies. The fruiting bodies or sporangia are what we commonly see, superficially look like fungi or molds but they are not related to the true fungi. These sporangia will then release spores which hatch into amoebae to begin the life cycle again. Families & Genera Dictyosteliidae     Dictyostelium     Polysphondylium     Coenonia Actyosteliidae     Acytostelium The dictyostelids are a group of cellular slime moulds. ... The Percolozoa are a group of colorless protists including many that can transform between amoeboid, flagellate, and encysted stages, collectively referred to as schizopyrenids or amoeboflagellates. ... Genera Lignieria Membranosorus Octomyxa Phagomyxa Plasmodiophora Polymyxa Sorodiscus Sorosphaera Spongospora Tetramyxa Woronina The Phytomyxea are a group of protists that are parasites of plants. ... Genera Labyrinthulids    Labyrinthula Thraustochytrids    Aplanochytrium    Labyrinthuloides    Japonochytrium    Schizochytrium    Thraustochytrium    Ulkenia Diplophryids    Diplophrys The Labyrinthulomycetes are a group of protists that produce a network of filaments or tubes, which serve as tracks for the cells to glide along and absorb nutrients for them. ... Families & Genera Dictyosteliidae     Dictyostelium     Polysphondylium     Coenonia Actyosteliidae     Acytostelium The dictyostelids are a group of cellular slime moulds. ... Supergroups Opisthokonta Amoebozoa Unikont is a eukaryotic cell with a single flagellum, at least ancestrally. ... Subgroups Mycetozoa(slime moulds) Archamoebae    Pelobiontida    Entamoebida Gymnamoebia Various others The Amoebozoa are a major group of amoeboid protozoa, including the majority that move by means of internal cytoplasmic flow. ... A Bikont is a eukaryotic cell with two flagella. ... Species Plasmodium berghei Plasmodium brasilianum Plasmodium chabaudi Plasmodium cynomolgi Plasmodium falciparum Plasmodium gallinaceum Plasmodium knowlesi Plasmodium lophurae Plasmodium malariae Plasmodium ovale Plasmodium relictum Plasmodium vivax Plasmodium yoelii etc. ... HeLa cells stained for DNA with the Blue Hoechst dye. ...

History

The Slime mold Lycogala epidendrum, then called Simonus Fungi cito crescentes, was first described in the year 1654. In 1753 Linnaeus described five separate species, laying the foundation for the nomenclature of slime molds. Slime molds were originally considered fungi by mycologists and amoebae by zoologists, respectively classified as Myxomycota or Myxomycetes (slime fungi) or Mycetozoa (fungus animals). All three names are still used among different groups of specialists. The first person to connect the different stages of the creature was Elias Fries; even though he still considered them to be species of fungi. A painting of Carolus Linnaeus Carl Linnaeus, also known after his ennoblement as Carl von Linné  ?, and who wrote under the Latinized name Carolus Linnaeus (May 23, 1707 – January 10, 1778), was a Swedish botanist who laid the foundations for the modern scheme of taxonomy. ... Mycology (from the Greek μύκης, meaning fungus) is the study of fungi, their genetic and biochemical properties, their taxonomy, and their use to humans as a source for tinder, medicinals (e. ... Zoology (from Greek: ζῴον, zoion, animal; and λόγος, logos, knowledge) is the biological discipline which involves the study of animals. ... Drawn image of Elias Magnus Fries Elias Magnus Fries (August 15, 1794 - February 8, 1878) was a Swedish botanist born at Femsjö in Smalandia. ...

Life cycle

The plasmodial slime molds begin as amoeboid cells each with a single haploid nucleus. These may begin feeding on bacteria and multiply. Under very moist conditions they may convert into biflagellate swarmers. If conditions become poor the unicellular amoebae can form walled off dormant resistant cells called cysts. Pairs of amoebas or swarmers can fuse and become zygotes if they are of different mating types. Haploid (meaning simple in Greek) cells have only one copy of each chromosome. ... A flagellum (plural, flagella) is a whip-like organelle that many unicellular organisms, and some multicellular ones, use to move about. ...

Most organisms reproduce by cell fission when their cells reach a certain size, that is, the nucleus divides by mitosis and the cell divides with it to result in two smaller daughter cells each with their own nucleus. This is what haploid slime mold amoebae do. However the diploid zygotes act differently from most other organism. Instead of cell divisions myxomycete zygotes just grow bigger. The nucleus divides by mitosis, but the cell does not divide with it, resulting in a new larger cell with two nuclei. This is called a coenocyte (or plasmodium). As the coenocyte grows, the nuclei keep dividing. In some species the plasmodium will be meters in size with thousands of nuclei. Mitosis divides genetic information during cell division. ...

This plasmodium spreads out like an amoeba and migrates slowly at about 1 cm. per hour. It continues to grow and feed on various microorganisms in the rotting vegetable matter the slime molds live on. When environmental conditions change or food runs out, the slime mold changes behavior. It migrates to the outer surface of a rotting log if that's where it is living or it migrates up grass blades, etc. It then transforms into a fruiting body or sporangia. In different species these take on many forms from amorphous blobs to delicate lacy structures. A sporangium (pl. ...

First, the nuclei undergo meiosis and become haploid. Then, cell membranes finally form around each of these nuclei one to a cell, to form normal cells again. Other structures like stalks and fibers to hold the spores in place may also form. Finally the cells transform into spores, the structure dries out and the spores can be released into the air to travel to new substrates. These spores are haploid like the original amoebae from which the slime mold started. For the figure of speech, see meiosis (figure of speech). ... Haploid (meaning simple in Greek) cells have only one copy of each chromosome. ... Haploid (meaning simple in Greek) cells have only one copy of each chromosome. ...

These spores can then germinate. They will either form new amoebae to begin the cycle over again, or they may form biflagellate swarming cells. These cells (still haploid) serve as gametes and start the cycle over again. A flagellum (plural, flagella) is a whip-like organelle that many unicellular organisms, and some multicellular ones, use to move about. ... Gametes (in Greek: γαμέτες) —also known as sex cells, germ cells, or spores—are the specialized cells that come together during fertilization (conception) in organisms that reproduce sexually. ...

Under dry conditions, the plasmodia can also form resting structures called sclerotia, which then begin growing again when moist conditions come back. Sclerotia are compact or hard masses of mycelium Categories: Fungi stubs ...

Types of slime mold

Mycetozoa from Ernst Haeckel's 1904 Kunstformen der Natur (Artforms of Nature)

Most slime mold are smaller than a few centimeters, but the very largest reach areas of up to thirty square meters^{[citation needed]}, making them the largest undivided cells known. Many have bright colors such as yellow, brown, and white. Image File history File links Download high resolution version (2332x3271, 1920 KB) Summary The 93rd plate from Ernst Haeckels Kunstformen der Natur (1904), depicting organisms classified as Mycetozoa. ... Image File history File links Download high resolution version (2332x3271, 1920 KB) Summary The 93rd plate from Ernst Haeckels Kunstformen der Natur (1904), depicting organisms classified as Mycetozoa. ... Ernst Haeckel. ...

A common slime mold which forms tiny brown tufts on rotting logs is Stemonitis. Another form which lives in rotting logs and is often used in research is Physarum polycephalum. In logs it has the appearance of a slimy webwork of yellow threads, up to a few feet in size. Fuligo forms yellow crusts in mulch. Species Stemonitis is a distinctive genus of slime moulds found throughout the world (except Antarctica). ... Physarum polycephalum belongs to phylum Amoebozoa, infraphylum Mycetozoa, and class Myxogastrea. ... Fuligo is a genus of plasmodial slime mould. ...

The Protostelids life cycle is very similar to the above descriptions, but these are much smaller, the fruiting bodies only forming one to a few spores.

The Dictyosteliida, cellular slime molds, are distantly related to the plasmodial slime molds and have a very different life style. Their amoeba do not form huge coenocytes and remain individual. They live in similar habitats and also feed on microorganisms. When food runs out and they are ready to form sporangia, they do something radically different. They release signal molecules into their environment, by which they find each other and create swarms. These amoeba then join up into a tiny multicellular slug like coordinated creature which crawls to an open lit place and grows into a fruiting body. Some of the amoebae become spores to begin the next generation, but some of the amoebae sacrifice themselves to become a dead stalk, lifting the spores up into the air. Families & Genera Dictyosteliidae     Dictyostelium     Polysphondylium     Coenonia Actyosteliidae     Acytostelium The dictyostelids are a group of cellular slime moulds. ...

The Acrasidae, have a similar life style to Dictyostelids, but their amoebae behave differently and are of uncertain taxonomic position. The Percolozoa are a group of colorless protists including many that can transform between amoeboid, flagellate, and encysted stages, collectively referred to as schizopyrenids or amoeboflagellates. ...

The Plasmodiophorids also form coenocytes but are internal parasites of plants (e.g., club root disease of cabbages). Genera Lignieria Membranosorus Octomyxa Phagomyxa Plasmodiophora Polymyxa Sorodiscus Sorosphaera Spongospora Tetramyxa Woronina The Phytomyxea are a group of protists that are parasites of plants. ... Clubroot is a disease of cabbages, radishes, turnips, and other plants belonging to the family Cruciferae (mustard family). ...

Finally the Labyrinthulomycetes are marine and form labyrynthine networks of tubes in which amoebae without pseudopods can travel. Genera Labyrinthulids    Labyrinthula Thraustochytrids    Aplanochytrium    Labyrinthuloides    Japonochytrium    Schizochytrium    Thraustochytrium    Ulkenia Diplophryids    Diplophrys The Labyrinthulomycetes are a group of protists that produce a network of filaments or tubes, which serve as tracks for the cells to glide along and absorb nutrients for them. ... Pseudopods or pseudopodia (false feet) are temporary projections of eukaryotic cells. ...

Evolutionary origins

It now appears that the protostelids gave rise to both the myxogastrids and dictyostelids. Families & Genera Dictyosteliidae     Dictyostelium     Polysphondylium     Coenonia Actyosteliidae     Acytostelium The dictyostelids are a group of cellular slime moulds. ...

Utility in research

Slime mold on lawn, USA. Trail of movement can be seen.

Dictyostelids are used as examples of cellular communication and differentiation, and may provide insights into how multicellular organisms develop. Image File history File links Download high-resolution version (1179x885, 327 KB) Summary Photograph by Daniel Puleo. ... Image File history File links Download high-resolution version (1179x885, 327 KB) Summary Photograph by Daniel Puleo. ... Multicellular organisms are those organisms containing more than one cell, and having differentiated cells that perform specialized functions. ... In biology and ecology, an organism (in Greek organon = instrument) is a living being. ...

Slime molds like Physarum polycephalum are useful for studying cytoplasmic streaming. They have also been used to study the biochemical events which surround mitosis since all the nuclei in a medium sized plasmodium divide in syncrony. It has been observed that they can find their way through mazes by spreading out and choosing the shortest path, an interesting example of information processing without a nervous system. Myxomycete plasmodia have also been used to study the genetics of asexual cell fusion. The giant size of the plasmodial cells allows for an easy evaluation of complete cell fusion or partial cell fusion. Physarum polycephalum belongs to phylum Amoebozoa, infraphylum Mycetozoa, and class Myxogastrea. ... Cytoplasmic streaming is the flowing of cytoplasm in eukaryotic cells. ... The Human Nervous System. ...

In 2006, researchers at the University of Southampton and the University of Kobe reported that they had built a six-legged robot whose movement was remotely controlled by a Physarum slime mold. The mold directed the robot into a dark corner most similar to its natural habitat. Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... The University of Southampton is a university situated in the city of Southampton, on the south coast of Great Britain. ... Kobe University in Japan (神戸大学 Kobe Daigaku, abbreviated to 神大 Shindai) is one of the top-rating national universities. ... For other uses, see robot (disambiguation). ...

Slime molds are sometimes studied in advanced mathematics courses. Slime mold aggregation is a natural process that can be approximated with partial differential equations. In mathematics, and in particular analysis, a partial differential equation (PDE) is an equation involving partial derivatives of an unknown function. ...

Slime molds in culture

Slime mold from Olympic National Park, USA (Possibly Physarum)

Although usually overlooked, slime molds have occasionally found their way into art and literature. Traditional Finnish lore describes how malicious witches used yellow Fuligo (there called "paranvoi," or butter of the familiar) to spoil milk. More recently, in the popular RPG NetHack, "slime mold" is the default name of a sought-after and delicious food item. Whether or not most actual slime molds are delicious, or even edible, is unclear, and some may be poisonous. However, mycologist Tom Volk reports that the plasmodium of Fuligo is eaten in Mexico. ^[1] The graphic novel Nausicaä of the Valley of Wind features a highly dangerous mutated slime mold that engulfs entire cities. Philip K. Dick's novel Clans of the Alphane Moon contains a character called Lord Running Clam, that is a "Ganymedean Slime Mold", who talks and is very intelligent and has telepathic powers. In Jeffrey Darlington's comic General Protection Fault, one character's poor hygiene led to the development of a sentient species of slime mold in his apartment that split the rent with him. In the DVD release of "This is Spinal Tap" there is an outtake of an interview with David St. Hubbins where he speaks of slime molds, saying "They are both plant AND animal...it's like they can't make up their mind...and, you know, they think it's them...who've been running the earth all this time." Wikipedia does not have an article with this exact name. ... Wikipedia does not have an article with this exact name. ... Olympic National Park is located in the U.S. state of Washington, in the far northwestern part of the state known as the Olympic Peninsula. ... It has been suggested that this article or section be merged into Witchcraft. ... In witchcraft, a familiar spirit, commonly called familiar (from Middle English familiar, related to family) is a spirit who obeys a witch, conjurer, etc. ... A glass of cows milk. ... This article is about the role-playing game. ... This article is about the dangerous substance. ... Fuligo is a genus of plasmodial slime mould. ... It has been suggested that Chikuku be merged into this article or section. ... In biology, mutations are changes to the genetic material (usually DNA or RNA). ... Philip Kindred Dick (December 16, 1928 – March 2, 1982) was an American writer, mostly known for his works of science fiction. ... Clans of the Alphane Moon is a 1964 science fiction novel by Philip K. Dick. ... Telepathy from the Greek τηλε, tele, distant, and πάθεια, patheia, feeling, is the supposed ability to communicate information from one mind to another, and is one form of extra-sensory perception or anomalous cognition. ... General Protection Fault (or GPF) is a webcomic created by Jeffrey T. Darlington. ... This Is Spin̈al Tap (which is officially spelled with a non-functional umlaut symbol over the N) is a 1984 mockumentary directed by Rob Reiner and starring members of the semi-fictional heavy-metal glam rock band Spinal Tap. ... David St. ...

References

• Sleigh, Michael. "Protozoa and Other Protists". Routledge, Chapman and Hall Inc. 1989
• Alexopolous, C.J., Charles W. Mims, M. Blackwell et al., Introductory Mycology, 4^th ed. (John Wiley and Sons, Hoboken NJ, 2004) ISBN 0-471-52229-5
• Martin, G.W and C. J. Alexopoulos. 1969. "The Myxomycota" Iowa University Press.
• Ling, H. 1968. "Light and Fruiting in Didymium iridis" Mycologia Vol. pp 966-970.
• Lister,A. 1925. "A Monograph of the Mycetozoa" Johnson Reprint Corp. NY.
• Raper, K.B. (1984) The Dictyostelids. Princeton University Press.
• Karling, J.S. (1968) The Plasmodiophorales. Hafner Publishing Co.
• Bill Bryson's "A Short History of Nearly Everything".
• Nick Arnold's "Nasty Nature" (a volume in the "Horrible Science" series).

External links

Wikimedia Commons has media related to:

Mycetozoa

• Slime Molds
• Slime Mould Solves Maze Puzzle from abc.net.au
• Hunting Slime Molds from Smithsonian Magazine
• Robot Piloted by a Slime Mold. Slashdot (2006). Retrieved on February 15, 2006.
• dictyBase is an online informatics resource for Dictyostelium, a cellular slime mould.
• nomen.eumycetozoa.com is an online nomenclatural information system of slime moulds (Myxomycetes, Dictyostelids and Protostelids) of the world.
• good photo gallery