Amoebophilus | |
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Thallus of Amoebophilus sp. infecting an unidentified amoeba. | |
Scientific classification ![]() | |
Kingdom: | Fungi |
Subdivision: | Zoopagomycotina |
Class: | Zoopagomycetes |
Order: | Zoopagales |
Family: | Cochlonemataceae |
Genus: | Amoebophilus Dangeard (1910) |
Type species | |
Amoebophilus penardii Dangeard (1910) [1] |
Amoebophilus is a genus of zygomycete fungi that parasitizes amoeba. [2]
Amoebophilus species are ectoparasites of amoeba. The thallus is composed of an internal haustorium that can be heart-shaped, globose, or lobose. Trailing chains of four or more conidia are produced from the haustorium. Zygospores are spherical at first and become polyhedral with age. [2]
Amoebophilus species have been reported from forest and agricultural soils and freshwater ponds where they infect free living amoeba. [2] [3] [4] [5] Infection begins when a conidium comes in contact with an amoeba. The conidium produces a penetration tube to invade the host and form the haustorium. Once the haustorium is formed, the conidium germinates and gives rise to a chain of conidia. [2] Due to difficulties in identifying amoeba, the host ranges of most species are unknown, with the exception of Amoebophilus simplex, which is restricted to species of Mayorella . [4] [5]
Amoebophilus species were first observed by Leidy in 1874 who mistook them as part of the amoeba and used them to describe a new genus. In 1902, Penard pointed out that the filaments observed by Leidy were in fact a parasite. [4] The genus was formerly erected by Dangeard in 1910 based on parasitized individuals of Pelomyxa vorax ; he named the species after Penard. [2]
Zygomycota, or zygote fungi, is a former division or phylum of the kingdom Fungi. The members are now part of two phyla the Mucoromycota and Zoopagomycota. Approximately 1060 species are known. They are mostly terrestrial in habitat, living in soil or on decaying plant or animal material. Some are parasites of plants, insects, and small animals, while others form symbiotic relationships with plants. Zygomycete hyphae may be coenocytic, forming septa only where gametes are formed or to wall off dead hyphae. Zygomycota is no longer recognised as it was not believed to be truly monophyletic.
A conidium, sometimes termed an asexual chlamydospore or chlamydoconidium, is an asexual, non-motile spore of a fungus. The name comes from the Greek word for dust, κόνις kónis. They are also called mitospores due to the way they are generated through the cellular process of mitosis. The two new haploid cells are genetically identical to the haploid parent, and can develop into new organisms if conditions are favorable, and serve in biological dispersal.
An entomopathogenic fungus is a fungus that can act as a parasite of insects and kills or seriously disables them.
The Archamoebae are a group of protists originally thought to have evolved before the acquisition of mitochondria by eukaryotes. They include genera that are internal parasites or commensals of animals. A few species are human pathogens, causing diseases such as amoebic dysentery. The other genera of archamoebae live in freshwater habitats and are unusual among amoebae in possessing flagella. Most have a single nucleus and flagellum, but the giant amoeba Pelomyxa has many of each.
Arcellinid testate amoebae or Arcellinida, Arcellacean or lobose testate amoebae are single-celled protists partially enclosed in a simple test (shell).
Massospora cicadina is a fungal pathogen that infects only 13 and 17 year periodical cicadas. Infection results in a "plug" of spores that replaces the end of the cicada's abdomen while it is still alive, leading to infertility, disease transmission, and eventual death of the cicada.
Entomophthora muscae is a species of pathogenic fungus in the order Entomophthorales which causes a fatal disease in flies. It can cause epizootic outbreaks of disease in houseflies and has been investigated as a potential biological control agent.
Sappinia is a genus of heterotrophic, lobose amoebae within the family Thecamoebidae. A defining feature of Sappinia, which separates it from its sister genus Thecamoeba, is the presence of two closely apposed nuclei with a central, flattened connection. Sappinia species have two life cycle stages: a trophozoite and a cyst. Up until 2015, only two species had been discovered, Sappinia pedata and Sappinia diploidea. Sequencing of the small subunit rRNA of a particular isolate from a sycamore tree revealed a new species, Sappinia platani.Sappinia species were once thought to be coprozoic, as the first strains were isolated from animal dung. More research has shown that they are typical free-living amoebae, and can be found worldwide in soil, plant litter, and standing decaying plants, as well as freshwater ponds. In 2001, the first and only case of human pathogenesis in Sappinia was confirmed. The patient was a non-immunocompromised 38-year-old male who presented signs of amoebic encephalitis and who patient made a full recovery after treatment with several antimicrobials. The CDC initially classified the causative agent as S. diploidea based on morphological characteristics, but in 2009, Qvarnstrom et al. used molecular data to confirm that the true causative agent was S. pedata.
The Zoopagomycotina are a subdivision of the fungal division Zygomycota sensu lato. It contains 5 families and 20 genera. Relationships among and within subphyla of Zygomycota are poorly understood, and their monophyly remains in question, so they are sometimes referred to by the informal name zygomycetes.
Cochliopodium is a Himatismenida genus.
Arcella is a genus of testate amoebae in the order Arcellinida, usually found in freshwaters and mosses, and rarely in soils. A key characteristic of Arcella is the circular test with a hole on its center from where finger-like pseudopods emerge. It is one of the largest testacean genera.
Testate amoebae are a polyphyletic group of unicellular amoeboid protists, which differ from naked amoebae in the presence of a test that partially encloses the cell, with an aperture from which the pseudopodia emerge, that provides the amoeba with shelter from predators and environmental conditions.
Rhopalomyces elegans is a common species of zygomycete fungus, and the type species of the genus Rhopalomyces. Widely distributed, it is found in soil, rotting plant material, and animal dung. It is a facultative parasite of nematode eggs.
Zoophthora is a genus of fungi in the family Entomophthoraceae. Like other taxa in this family, Zoophthora species cause disease in insects and as such are considered entomopathogenic fungi.
Charles Drechsler was an American mycologist with 45 years of research with the United States Department of Agriculture. He spent considerable time working with cereal fungal diseases, and the genus Drechslera was named after him. Drechsler also worked extensively on oomycete fungi and their interactions with vegetable plants. Drechsler was recognized as a leading authority on helminthosporia, oomycetes, and other parasitic fungi.
Entomophaga grylli is a fungal pathogen which infects and kills grasshoppers. It is the causal agent of one of the most widespread diseases affecting grasshoppers. This is sometimes known as summit disease because infected insects climb to the upper part of a plant and grip the tip of the stem as they die; this ensures widespread dispersal of the fungal spores. The fungus is a species complex with several different pathotypes, each one of which seems to be host-specific to different subfamilies of grasshoppers. The pathogen is being investigated for its possible use in biological pest control of grasshoppers.
Trichothecium roseum is a fungus in the division Ascomycota first reported in 1809. It is characterized by its flat and granular colonies which are initially white and develop to be light pink in color. This fungus reproduces asexually through the formation of conidia with no known sexual state. Trichothecium roseum is distinctive from other species of the genus Trichothecium in its characteristic zigzag patterned chained conidia. It is found in various countries worldwide and can grow in a variety of habitats ranging from leaf litter to fruit crops. Trichothecium roseum produces a wide variety of secondary metabolites including mycotoxins, such as roseotoxins and trichothecenes, which can infect and spoil a variety of fruit crops. It can act as both a secondary and opportunistic pathogen by causing pink rot on various fruits and vegetables and thus has an economical impact on the farming industry. Secondary metabolites of T. roseum, specifically Trichothecinol A, are being investigated as potential anti-metastatic drugs. Several agents including harpin, silicon oxide, and sodium silicate are potential inhibitors of T. roseum growth on fruit crops. Trichothecium roseum is mainly a plant pathogen and has yet to show a significant impact on human health.
Harposporium anguillulae is a member of the genus Harposporium. It is an endoparasitic nematophagous fungus that attacks nematodes and eelworms and is isolated commonly from field and agricultural soils as well as used as an experimental organism in the laboratory.
Acaulopage is a genus in the former Zygomycota that preys on amoeba.
Stylopage is a polytypic genus of predacious fungus in the order Zoopagales, within the subphylum Zoopagomycotina. All known species of Stylopage subsist on various species of amoebae or nematodes by trapping their prey, typically using an adhesive substance that coats their vegetative hyphae, and absorbing nutrients through the projection of a haustorium. 17 extant Stylopage species have been described thus far.