Cephems are a sub-group of β-lactam antibiotics including cephalosporins and cephamycins. It is one of the most common 4-membered ring heterocycle. Produced by actinomycetes, cephamycins were found to display antibacterial activity against a wide range of bacteria, including those resistant to penicillin and cephalosporins. The antimicrobial properties of Cephem include the attachment to certain penicillin-binding proteins that are involved in the production of cell walls of bacteria.
Hitachimycin, also known as stubomycin, is a cyclic polypeptide produced by Streptomyces that acts as an antibiotic. It exhibits cytotoxic activity against mammalian cells, Gram-positive bacteria, yeast, and fungi, as well as hemolytic activity; this is mediated by changes at the cell membrane and subsequent lysis. Owing to its cytotoxic activity against mammalian cells and tumors, it was first proposed as an antitumor antibiotic.
The calicheamicins are a class of enediyne antitumor antibiotics derived from the bacterium Micromonospora echinospora, with calicheamicin γ1 being the most notable. It was isolated originally in the mid-1980s from the chalky soil, or "caliche pits", located in Kerrville, Texas. The sample was collected by a scientist working for Lederle Labs. It is extremely toxic to all cells and, in 2000, a CD33 antigen-targeted immunoconjugate N-acetyl dimethyl hydrazide calicheamicin was developed and marketed as targeted therapy against the non-solid tumor cancer acute myeloid leukemia (AML). A second calicheamicin-linked monoclonal antibody, inotuzumab ozogamicin an anti-CD22-directed antibody-drug conjugate, was approved by the U.S. Food and Drug Administration on August 17, 2017, for use in the treatment of adults with relapsed or refractory B-cell precursor acute lymphoblastic leukemia. Calicheamicin γ1 and the related enediyne esperamicin are the two of the most potent antitumor agents known.
Rhizoxin is an antimitotic agent with anti-tumor activity. It is isolated from a pathogenic plant fungus which causes rice seedling blight.
Rebeccamycin (NSC 655649) is a weak topoisomerase I inhibitor isolated from Nocardia sp. It is structurally similar to staurosporine, but does not show any inhibitory activity against protein kinases. It shows significant antitumor properties in vitro (IC50=480nM against mouse B16 melanoma cells and IC50=500nM against P388 leukemia cells). It is an antineoplastic antibiotic and an intercalating agent.
Macbecin belongs to the ansamycin family of antibiotics and was first isolated from actinomycete bacteria. Macbecin possesses potent antitumor properties. In-vitro studies have shown that Macbecin is effective in the eradication of Gram-positive bacteria, fungi, and protozoa including Tetrahymena pyriformis.
In organic chemistry, enediynes are organic compounds containing two triple bonds and one double bond.
Micromonospora echinospora is a species of bacteria that is known for producing the enediyne antibiotic calicheamicins.
Romidepsin, also known as Istodax, is an anticancer agent used in cutaneous T-cell lymphoma (CTCL) and other peripheral T-cell lymphomas (PTCLs). Romidepsin is a natural product obtained from the bacterium Chromobacterium violaceum, and works by blocking enzymes known as histone deacetylases, thus inducing apoptosis. It is sometimes referred to as depsipeptide, after the class of molecules to which it belongs. Romidepsin is branded and owned by Gloucester Pharmaceuticals, now a part of Celgene.
Alazopeptin is an antibiotic, with moderate anti-trypanosomal and antitumor activity. It was originally isolated from Streptacidiphilus griseoplanus, sourced from soil near Williamsburg, Iowa. It is also isolated from Kitasatospora azatica. It is still largely produced via fermentation broths of that organism. Structurally, alazopeptin is a tripeptide and contains 2 molecules of 6-diazo-5-oxo-L-norleucine and one molecule of L-alanine. In 2021 the biosynthetic pathway of alazopeptin was elucidated.
DB-2073 is an alkylresorcinol antibiotic isolated from the broth culture of Pseudomonas sp B-9004.
Venturicidins are a group of antifungal compounds. The first member of this class was isolated from Streptomyces bacteria in 1961. Additional members of this class were subsequently isolated and characterized. An antifungal substance "aabomycin A" was isolated from Streptomyces in 1969. However, in 1990 it was reported that aabomycin A is actually a 3:1 mixture of two related components, which were then named aabomycin A1 and aabomycin A2. The structures of these were shown to be identical with those of the previously characterized compounds venturicidin A and venturicidin B, respectively. A new analog, venturicidin C, was recently reported from a Streptomyces isolated from thermal vents associated with the Ruth Mullins coal fire in Kentucky.
Neopluramycin is an antibiotic that inhibits nucleic acid synthesis. It has been isolated from the cultured broth of a strain of Streptomyces pluricolorescens as orange crystals, and analytical data and molecular weight determination are consistent with the empirical formula C
41H
50N
2O
10.
Xanthomycin A is an antibiotic with in vitro antitumor activity isolated from Streptomyces.
Altemicidin is monoterpene alkaloid first identified in isolates from marine actinomycetes in 1989. It may also be produced synthetically. Altemicidin displays both acaricidal and antitumor activity.
Streptomyces verticillus is a species of Gram-positive bacteria in the genus Streptomyces. Whilst screening fermentation broths of this species for bioactivity in the early 1960s, Hamao Umezawa and colleagues at the Institute of Microbial Chemistry in Tokyo identified a family of glycopeptide antitumor antibiotics called the bleomycins. Examples of the bleomycins in clinical use include bleomycin A2 (also known as bleomycin) and bleomycin A5 (also known as pingyangmycin). Both are used to treat lymphomas (e.g. Hodgkin's lymphoma), head and neck cancer, and testicular cancer.
Leinamycin is an 18-membered macrolactam produced by several species of Streptomyces atroolivaceus. This macrolactam has also been shown to exhibit antitumor properties as well as antimicrobial properties against gram-positive and gram-negative bacteria. The presence of a spiro-fused 1,3-dioxo-1,2-dithiolane moiety was a unique structural property at the time of this compound's discovery and it plays an important role in leinamycin's antitumor and antibacterial properties due to its ability to inhibit DNA synthesis.
Streptomyces kasugaensis is a bacterium species from the genus of Streptomyces which has been isolated from soil from the city Nara in Japan. Streptomyces kasugaensis produces kasugamycin and thiolutin.
C-1027 or Lidamycin is an antitumor antibiotic consisting of a complex of an enediyne chromophore and an apoprotein. It shows antibiotic activity against most Gram-positive bacteria. It is one of the most potent cytotoxic molecules known, due to its induction of a higher ratio of DNA double-strand breaks than single-strand breaks.
Estradiol dipropionate/hydroxyprogesterone caproate (EDP/OHPC), sold under the brand name EP Hormone Depot, is a combined estrogen–progestogen medication which is used in Japan. It is manufactured by Teikoku Zoki Pharmaceutical Co., Tokyo and contains 1 mg/mL estradiol dipropionate and 50 mg/mL hydroxyprogesterone caproate.
