Names | |
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IUPAC name 1,6,8-Trihydroxy-5-[(2R,4R,5S,6R)-5-hydroxy-6-methyl-4-(methylamino)oxan-2-yl]-3-methylbenzo[a]anthracene-7,12-dione | |
Other names Mayamycin A | |
Identifiers | |
3D model (JSmol) | |
ChemSpider | |
PubChem CID | |
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Properties | |
C26H25NO7 | |
Molar mass | 463.486 g·mol−1 |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). |
Mayamycin is a cytotoxic polyketide isolated from a marine Streptomyces . [1] [2]
Polyketides are a class of natural products derived from a precursor molecule consisting of a chain of alternating ketone (or reduced forms of a ketone) and methylene groups: (-CO-CH2-). First studied in the early 20th century, discovery, biosynthesis, and application of polyketides has evolved. It is a large and diverse group of secondary metabolites caused by its complex biosynthesis which resembles that of fatty acid synthesis. Because of this diversity, polyketides can have various medicinal, agricultural, and industrial applications. Many polyketides are medicinal or exhibit acute toxicity. Biotechnology has enabled discovery of more naturally-occurring polyketides and evolution of new polyketides with novel or improved bioactivity.
Okadaic acid, C44H68O13, is a toxin produced by several species of dinoflagellates, and is known to accumulate in both marine sponges and shellfish. One of the primary causes of diarrhetic shellfish poisoning, okadaic acid is a potent inhibitor of specific protein phosphatases and is known to have a variety of negative effects on cells. A polyketide, polyether derivative of a C38 fatty acid, okadaic acid and other members of its family have shined light upon many biological processes both with respect to dinoflagellete polyketide synthesis as well as the role of protein phosphatases in cell growth.
The avermectins are a series of drugs and pesticides used to treat parasitic worms and insect pests. They are a group of 16-membered macrocyclic lactone derivatives with potent anthelmintic and insecticidal properties. These naturally occurring compounds are generated as fermentation products by Streptomyces avermitilis, a soil actinomycete. Eight different avermectins were isolated in four pairs of homologue compounds, with a major (a-component) and minor (b-component) component usually in ratios of 80:20 to 90:10. Other anthelmintics derived from the avermectins include ivermectin, selamectin, doramectin, eprinomectin, and abamectin.
Doxorubicin (DXR) is a 14-hydroxylated version of daunorubicin, the immediate precursor of DXR in its biosynthetic pathway. Daunorubicin is more abundantly found as a natural product because it is produced by a number of different wild type strains of streptomyces. In contrast, only one known non-wild type species, streptomyces peucetius subspecies caesius ATCC 27952, was initially found to be capable of producing the more widely used doxorubicin. This strain was created by Arcamone et al. in 1969 by mutating a strain producing daunorubicin, but not DXR, at least in detectable quantities. Subsequently, Hutchinson's group showed that under special environmental conditions, or by the introduction of genetic modifications, other strains of streptomyces can produce doxorubicin. His group has also cloned many of the genes required for DXR production, although not all of them have been fully characterized. In 1996, Strohl's group discovered, isolated and characterized dox A, the gene encoding the enzyme that converts daunorubicin into DXR. By 1999, they produced recombinant Dox A, a Cytochrome P450 oxidase, and found that it catalyzes multiple steps in DXR biosynthesis, including steps leading to daunorubicin. This was significant because it became clear that all daunorubicin producing strains have the necessary genes to produce DXR, the much more therapeutically important of the two. Hutchinson's group went on to develop methods to improve the yield of DXR, from the fermentation process used in its commercial production, not only by introducing Dox A encoding plasmids, but also by introducing mutations to deactivate enzymes that shunt DXR precursors to less useful products, for example baumycin-like glycosides. Some triple mutants, that also over-expressed Dox A, were able to double the yield of DXR. This is of more than academic interest because at that time DXR cost about $1.37 million per kg and current production in 1999 was 225 kg per annum. More efficient production techniques have brought the price down to $1.1 million per kg for the non-liposomal formulation. Although DXR can be produced semi-synthetically from daunorubicin, the process involves electrophilic bromination and multiple steps and the yield is poor. Since daunorubicin is produced by fermentation, it would be ideal if the bacteria could complete DXR synthesis more effectively.
Enediynes are organic compounds containing two triple bonds and one double bond.
Pikromycin was studied by Brokmann and Hekel in 1951 and was the first antibiotic macrolide to be isolated. Pikromycin is synthesized through a type I polyketide synthase system in Streptomyces venezuelae, a species of Gram-positive bacterium in the genus Streptomyces. Pikromycin is derived from narbonolide, a 14-membered ring macrolide. Along with the narbonolide backbone, pikromycin includes a desosamine sugar and a hydroxyl group. Although Pikromycin is not a clinically useful antibiotic, it can be used as a raw material to synthesize antibiotic ketolide compounds such as ertythromycins and new epothilones.
Callystatin A is a polyketide natural product from the leptomycin family of secondary metabolites. It was first isolated in 1997 from the marine sponge Callyspongia truncata which was collected from the Goto Islands in the Nagasaki Prefecture of Japan by the Kobayashi group. Since then its absolute configuration has been elucidated and callystatin A was discovered to have anti-fungal and anti-tumor activities with extreme potency against the human epidermoid carcinoma KB cells (IG50 = 10 pg/ml) and the mouse lymphocytic leukemia Ll210 cells (IG50 = 20 pg/ml).
Streptomyces nodosus is a bacterial species in the genus Streptomyces.
Anthracimycin is a polyketide antibiotic discovered in 2013. Anthracimycin is derived from marine actinobacteria. In preliminary laboratory research, it has shown activity against Bacillus anthracis, the bacteria that causes anthrax, and against methicillin-resistant Staphylococcus aureus (MRSA).
Lacking an immune system, protective shell, or mobility, sponges have developed an ability to synthesize a variety of unusual compounds for survival. C-nucleosides isolated from Caribbean Cryptotethya crypta, were the basis for the synthesis of zidovudine (AZT), aciclovir (Cyclovir), cytarabine (Depocyt), and cytarabine derivative gemcitabine (Gemzar).
Streptomyces isolates have yielded the majority of human, animal, and agricultural antibiotics, as well as a number of fundamental chemotherapy medicines. Streptomyces is the largest antibiotic-producing genus of Actinomycetota, producing chemotherapy, antibacterial, antifungal, antiparasitic drugs, and immunosuppressants. Streptomyces isolates are typically initiated with the aerial hyphal formation from the mycelium.
Penicillium brocae is a fungal species of the genus Penicillium, which was isolated in Chiapas in Mexico. It is a symbiont of the mangrove tree Avicennia marina.
Streptomyces caelestis is a bacterium species from the genus of Streptomyces which has been isolated from soil in Utah in the United States. Streptomyces caelestis produces desalicetin, isocelesticetin B, caelesticetin, citreamicin θ A, citreamicin θ B, citreaglycon A and dehydrocitreaglycon.
Streptomyces glaucescens is a bacterium species from the genus of Streptomyces which has been isolated from soil. Streptomyces glaucescens produces tetracenomycin C, tetracenomycin D and tetracenomycin E.
Streptomyces platensis is a bacterium species from the genus of Streptomyces which has been isolated from soil. Streptomyces platensis produces oxytetracycline, platensimycin, migrastatin, isomigrastatin, platencin, dorrigocin A, dorrigocin B and terramycine.
Streptomyces resistomycificus is a bacterium species from the genus of Streptomyces which has been isolated from soil. Streptomyces resistomycificus produces the pentacyclic polyketide resistomycin.
Tsukamurella pulmonis is a Gram-positive and aerobic bacterium from the genus Tsukamurella which has been isolated from the sputum from a patient with lung tuberculosis in Germany.
A jadomycin is a natural product produced by Streptomyces venezuelae ISP5230 (ATCC10712), the organism which is most well known for making the antibiotic chloramphenicol. The name jadomycin is applied to a family of related angucyclines which are distinguished by the E ring, which is derived from an amino acid. The amino acid incorporation which forms the E-ring is a chemical reaction, rather than enzymatic, an uncommon occurrence in biosynthesis. As such a number of jadomycins incorporating different amino acids have been discovered. Jadomycin A was the first compound of this family to be isolated and constitutes the angucylic backbone with L-isoleucine incorporated into the E-ring. A related analog, jadomycin B, is modified by glycosylation with a 2,6-dideoxy sugar, L-digitoxose. Jadomycins have cytotoxic and antibacterial properties.
Fostriecin is a type I polyketide synthase (PKS) derived natural product, originally isolated from the soil bacterium Streptomyces pulveraceus. It belongs to a class of natural products which characteristically contain a phosphate ester, an α,β-unsaturated lactam and a conjugated linear diene or triene chain produced by Streptomyces. This class includes structurally related compounds cytostatin and phoslactomycin. Fostriecin is a known potent and selective inhibitor of protein serine/threonine phosphatases, as well as DNA topoisomerase II. Due to its activity against protein phosphatases PP2A and PP4 which play a vital role in cell growth, cell division, and signal transduction, fostriecin was looked into for its antitumor activity in vivo and showed in vitro activity against leukemia, lung cancer, breast cancer, and ovarian cancer. This activity is thought to be due to PP2A's assumed role in regulating apoptosis of cells by activating cytotoxic T-lymphocytes and natural killer cells involved in tumor surveillance, along with human immunodeficiency virus-1 (HIV-1) transcription and replication.
Aureothin is a natural product of a cytotoxic shikimate-polyketide antibiotic with the molecular formula C22H23NO6. Aureothin is produced by the bacterium Streptomyces thioluteus that illustrates antitumor, antifungal, and insecticidal activities and the new aureothin derivatives can be antifungal and antiproliferative. In addition, aureothin, a nitro compound from Streptomyces thioluteus, was indicated to have pesticidal activity against the bean weevil by interfering with mitochondrial respiratory complex II.