Gliotoxin
Encyclopedia
Gliotoxin is a sulfur-containing
mycotoxin
produced by several species of fungi
, some of which are pathogen
s of humans such as Aspergillus
, and also by species of Trichoderma
, and Penicillium
. Previously gliotoxin has also been reported in yeast
s of the genus Candida
; results of a recent study of 100 clinical Candida isolates, however, have cast doubt on the occurrence of this metabolite in this group of fungi. However, a study published in 1991 by Shah and Larsen found "Clinical Isolates of yeast produce a Gliotoxin like substance" in 32 of 50 isolates tested.It was originally isolated from Gliocladium fimbriatum, and was named accordingly. It is an epipolythiodioxopiperazine metabolite.
Gliotoxin possesses immunosuppressive properties as it may suppress and cause apoptosis
in certain types of cells of the immune system
, including neutrophils, eosinophils, granulocytes, macrophage
s, and thymocyte
s. It also acts as an inhibitor of farnesyl transferase. It noncompetitively inhibits the chymotrypsin
-like activity of the 20S proteasome
. In vivo
it displays anti-inflammatory
activity. It acts by blocking thiol
groups in the cell membrane
s. It was investigated as an antibiotic
and antifungal
in the 1940's and recently as an antiviral
agent.
Sulfur
Sulfur or sulphur is the chemical element with atomic number 16. In the periodic table it is represented by the symbol S. It is an abundant, multivalent non-metal. Under normal conditions, sulfur atoms form cyclic octatomic molecules with chemical formula S8. Elemental sulfur is a bright yellow...
mycotoxin
Mycotoxin
A mycotoxin is a toxic secondary metabolite produced by organisms of the fungus kingdom, commonly known as molds. The term ‘mycotoxin’ is usually reserved for the toxic chemical products produced by fungi that readily colonize crops...
produced by several species of fungi
Fungus
A fungus is a member of a large 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, Fungi, which is separate from plants, animals, and bacteria...
, some of which are pathogen
Pathogen
A pathogen gignomai "I give birth to") or infectious agent — colloquially, a germ — is a microbe or microorganism such as a virus, bacterium, prion, or fungus that causes disease in its animal or plant host...
s of humans such as Aspergillus
Aspergillus
Aspergillus is a genus consisting of several hundred mold species found in various climates worldwide. Aspergillus was first catalogued in 1729 by the Italian priest and biologist Pier Antonio Micheli...
, and also by species of Trichoderma
Trichoderma
Trichoderma is a genus of fungi that is present in all soils, where they are the most prevalent culturable fungi. Many species in this genus can be characterized as opportunistic avirulent plant symbionts.-Species:...
, and Penicillium
Penicillium
Penicillium is a genus of ascomycetous fungi of major importance in the natural environment as well as food and drug production. Members of the genus produce penicillin, a molecule that is used as an antibiotic, which kills or stops the growth of certain kinds of bacteria inside the body...
. Previously gliotoxin has also been reported in yeast
Yeast
Yeasts are eukaryotic micro-organisms classified in the kingdom Fungi, with 1,500 species currently described estimated to be only 1% of all fungal species. Most reproduce asexually by mitosis, and many do so by an asymmetric division process called budding...
s of the genus Candida
Candida (genus)
Candida is a genus of yeasts. Many species are harmless commensals or endosymbionts of animal hosts including humans, but other species, or harmless species in the wrong location, can cause disease. Candida albicans can cause infections in humans and other animals, especially in immunocompromised...
; results of a recent study of 100 clinical Candida isolates, however, have cast doubt on the occurrence of this metabolite in this group of fungi. However, a study published in 1991 by Shah and Larsen found "Clinical Isolates of yeast produce a Gliotoxin like substance" in 32 of 50 isolates tested.It was originally isolated from Gliocladium fimbriatum, and was named accordingly. It is an epipolythiodioxopiperazine metabolite.
Gliotoxin possesses immunosuppressive properties as it may suppress and cause apoptosis
Apoptosis
Apoptosis is the process of programmed cell death that may occur in multicellular organisms. Biochemical events lead to characteristic cell changes and death. These changes include blebbing, cell shrinkage, nuclear fragmentation, chromatin condensation, and chromosomal DNA fragmentation...
in certain types of cells of the immune system
Immune system
An immune system is a system of biological structures and processes within an organism that protects against disease by identifying and killing pathogens and tumor cells. It detects a wide variety of agents, from viruses to parasitic worms, and needs to distinguish them from the organism's own...
, including neutrophils, eosinophils, granulocytes, macrophage
Macrophage
Macrophages are cells produced by the differentiation of monocytes in tissues. Human macrophages are about in diameter. Monocytes and macrophages are phagocytes. Macrophages function in both non-specific defense as well as help initiate specific defense mechanisms of vertebrate animals...
s, and thymocyte
Thymocyte
Thymocytes are hematopoietic progenitor cells present in the thymus. Thymopoiesis is the process in the thymus by which thymocytes differentiate into mature T lymphocytes. The primary function of thymocytes is the generation of T lymphocytes . The thymus provides an inductive environment, which...
s. It also acts as an inhibitor of farnesyl transferase. It noncompetitively inhibits the chymotrypsin
Chymotrypsin
Chymotrypsin is a digestive enzyme that can perform proteolysis. Chymotrypsin preferentially cleaves peptide amide bonds where the carboxyl side of the amide bond is a tyrosine, tryptophan, or phenylalanine. These amino acids contain an aromatic ring in their sidechain that fits into a...
-like activity of the 20S proteasome
Proteasome
Proteasomes are very large protein complexes inside all eukaryotes and archaea, and in some bacteria. In eukaryotes, they are located in the nucleus and the cytoplasm. The main function of the proteasome is to degrade unneeded or damaged proteins by proteolysis, a chemical reaction that breaks...
. In vivo
In vivo
In vivo is experimentation using a whole, living organism as opposed to a partial or dead organism, or an in vitro controlled environment. Animal testing and clinical trials are two forms of in vivo research...
it displays anti-inflammatory
Anti-inflammatory
Anti-inflammatory refers to the property of a substance or treatment that reduces inflammation. Anti-inflammatory drugs make up about half of analgesics, remedying pain by reducing inflammation as opposed to opioids, which affect the central nervous system....
activity. It acts by blocking thiol
Thiol
In organic chemistry, a thiol is an organosulfur compound that contains a carbon-bonded sulfhydryl group...
groups in the cell membrane
Cell membrane
The cell membrane or plasma membrane is a biological membrane that separates the interior of all cells from the outside environment. The cell membrane is selectively permeable to ions and organic molecules and controls the movement of substances in and out of cells. It basically protects the cell...
s. It was investigated as an antibiotic
Antibiotic
An antibacterial is a compound or substance that kills or slows down the growth of bacteria.The term is often used synonymously with the term antibiotic; today, however, with increased knowledge of the causative agents of various infectious diseases, antibiotic has come to denote a broader range of...
and antifungal
Antifungal
* Antifungal medication, a medication used to treat fungal infection s such as athlete's foot , ringworm, candidiasis, etc.* Antifungal protein, a protein family* an adjective referring to a fungicide compound...
in the 1940's and recently as an antiviral
Antiviral
Antiviral may refer to:*Antiviral drug*Antiviral protein*Antivirus software*Antiviral Therapy, an academic journal...
agent.
External links
- Gliotoxin product page from FermentekFermentekFermentek Ltd. is a biotechnological company, located in Atarot industrial zone, Jerusalem, Israel, specializing in the research, development and manufacture of biologically active, natural products isolated from microorganisms as well as from other natural sources such as plants and algae.The main...