''Apophysomyces'' is a
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 ...
of filamentous
fungi
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 ...
that are commonly found in soil and decaying vegetation. Species normally grow in
tropical
The tropics are the regions of Earth surrounding the Equator. They are defined in latitude by the Tropic of Cancer in the Northern Hemisphere at N and the Tropic of Capricorn in
the Southern Hemisphere at S. The tropics are also referred to ...
to
subtropical
The subtropical zones or subtropics are geographical zone, geographical and Köppen climate classification, climate zones to the Northern Hemisphere, north and Southern Hemisphere, south of the tropics. Geographically part of the Geographical z ...
regions.
The genus ''Apophysomyces'' historically was
monospecific
In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unispec ...
, containing only the
type species
In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specimen ...
''
Apophysomyces elegans
''Apophysomyces'' is a genus of filamentous fungi that are commonly found in soil and decaying vegetation. Species normally grow in tropical to subtropical regions.
The genus ''Apophysomyces'' historically was monospecific, containing only the t ...
''. In 2010, three new species were described: ''variabilis'', ''trapeziformis'', and ''ossiformis''.
Characteristics
Among the other members of zygomycetes, ''Apophysomyces elegans'' mostly resembles those from genus ''
Absidia
''Absidia'' is a genus of zygote fungi in the family Cunninghamellaceae. ''Absidia'' species are ubiquitous in most environments where they are often associated with warm decaying plant matter, such as compost heaps. Some species in the genus ...
''. However, its bell-shaped (although not conical) apophyses (outgrowth), the existence of its foot-cell like
hypha
A hypha (; ) is a long, branching, filamentous structure of a fungus, oomycete, or actinobacterium. In most fungi, hyphae are the main mode of vegetative growth, and are collectively called a mycelium.
Structure
A hypha consists of one or ...
l segment,
rhizoid
Rhizoids are protuberances that extend from the lower epidermal cells of bryophytes and algae. They are similar in structure and function to the root hairs of vascular land plants. Similar structures are formed by some fungi. Rhizoids may be unic ...
s produced opposite to the sporangiophores upon cultivation on plain
agar
Agar ( or ), or agar-agar, is a jelly-like substance consisting of polysaccharides obtained from the cell walls of some species of red algae, primarily from ogonori (''Gracilaria'') and "tengusa" (''Gelidiaceae''). As found in nature, agar is ...
, the darker and thicker
subapical
A subapical consonant is a consonant made by contact with the underside of the tip of the tongue. The only common subapical articulations are in the postalveolar to palatal region, which are called "retroflex".
Most so-called retroflex consonants ...
segment, and inability to
sporulate on routine culture media help in distinguishing ''Apophysomyces elegans''.
[Davise H. Larone, "Medically Important Fungi - A Guide to Identification", 3rd ed. (1995). (ASM Press, Washington, D.C.). (ISBN is for 4th ed.)]
''Apophysomyces elegans'' is a thermotolerant fungus: it has been found to grow favourably at temperatures of 26 °C and 37 °C, and it grows rapidly at 42 °C. Its colonies are fluffy and cottony in appearance. The surface of the colony is white initially and turns to a brownish-grey or yellowish-cream as the culture ages, while the underside is white to pale yellow in colour.
Pathogenicity
Normally, no special precautions are needed with regard to this
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 ...
.
However, ''Apophysomyces elegans'' and ''Apophysomyces trapeziformis'' are able to cause
mucormycosis
Mucormycosis, also known as black fungus, is a serious fungal infection that comes under fulminant fungal sinusitis, usually in people who are immunocompromised. It is curable only when diagnosed early. Symptoms depend on where in the body the ...
, in humans, which is often fatal but very rare.
Reports of other mammals being infected are mostly restricted to captive species, but in 2021 a female
lesser long-nosed bat was found with
mucormycosis
Mucormycosis, also known as black fungus, is a serious fungal infection that comes under fulminant fungal sinusitis, usually in people who are immunocompromised. It is curable only when diagnosed early. Symptoms depend on where in the body the ...
in the wild.
Infection is usually acquired via traumatic implantations associated with soil or decaying vegetable matter (such as from accidental injuries or insect bites). Invasive soft tissue infections can develop on burns or wounds which are contaminated by soil. Unlike other
zygomycosis
Zygomycosis is the broadest term to refer to infections caused by ''bread mold fungi'' of the zygomycota phylum. However, because zygomycota has been identified as polyphyletic, and is not included in modern fungal classification systems, the dise ...
, the affected host is usually otherwise
immunocompetent
In immunology, immunocompetence is the ability of the body to produce a normal immune response following exposure to an antigen. Immunocompetence is the opposite of immunodeficiency (also known as ''immuno-incompetence'' or being ''immuno-comprom ...
. ''Apophysomyces elegans'' infections present most commonly as
necrotizing fasciitis
Necrotizing fasciitis (NF), also known as flesh-eating disease, is a bacterial infection that results in the death of parts of the body's soft tissue. It is a severe disease of sudden onset that spreads rapidly. Symptoms usually include red or p ...
and/or
osteomyelitis
Osteomyelitis (OM) is an infection of bone. Symptoms may include pain in a specific bone with overlying redness, fever, and weakness. The long bones of the arms and legs are most commonly involved in children e.g. the femur and humerus, while the ...
.
Systemic and secondary renal and
bladder infection
A urinary tract infection (UTI) is an infection that affects part of the urinary tract. When it affects the lower urinary tract it is known as a bladder infection (cystitis) and when it affects the upper urinary tract it is known as a kidney ...
s
have also been reported.
See also
*
Mucormycosis
Mucormycosis, also known as black fungus, is a serious fungal infection that comes under fulminant fungal sinusitis, usually in people who are immunocompromised. It is curable only when diagnosed early. Symptoms depend on where in the body the ...
(specific term for infection caused by fungi of the order Mucorales)
*
Zygomycosis
Zygomycosis is the broadest term to refer to infections caused by ''bread mold fungi'' of the zygomycota phylum. However, because zygomycota has been identified as polyphyletic, and is not included in modern fungal classification systems, the dise ...
(a more generic term for infection caused by Mucoraceae and various other fungus varieties; the term
Mucormycosis
Mucormycosis, also known as black fungus, is a serious fungal infection that comes under fulminant fungal sinusitis, usually in people who are immunocompromised. It is curable only when diagnosed early. Symptoms depend on where in the body the ...
is preferred).
References
External links
Image of ''Apophysomyces sp.''''Apophysomyces'' species
from Index Fungorum
PubMed search page
(using search term "''apophysomyces''")
{{Taxonbar, from=Q4780512
Mucoraceae
Zygomycota genera