Macbecins are a pair of chemical compounds in the

ansamycin Ansamycins is a family of bacterial secondary metabolites that show antimicrobial activity against many Gram-positive and some Gram-negative bacteria, and includes various compounds, including streptovaricins and rifamycins. In addition, these ...

family of

antibiotic An antibiotic is a type of antimicrobial substance active against bacteria. It is the most important type of antibacterial agent for fighting pathogenic bacteria, bacterial infections, and antibiotic medications are widely used in the therapy ...

s. They are designated macbecin I and macbecin II and they were first isolated from

actinomycete The Actinomycetales is an order of Actinomycetota. A member of the order is often called an actinomycete. Actinomycetales are generally gram-positive and anaerobic and have mycelia in a filamentous and branching growth pattern. Some actinomycetes ...

bacteria. Macbecin possesses

antitumor Cancer treatments are a wide range of treatments available for the many different types of cancer, with each cancer type needing its own specific treatment. Treatments can include surgery, chemotherapy, radiation therapy, hormonal therapy, targe ...

properties. ''

In vitro ''In vitro'' (meaning ''in glass'', or ''in the glass'') Research, studies are performed with Cell (biology), cells or biological molecules outside their normal biological context. Colloquially called "test-tube experiments", these studies in ...

'' studies have shown that macbecins are effective in the eradication of

Gram-positive bacteria In bacteriology, gram-positive bacteria are bacteria that give a positive result in the Gram stain test, which is traditionally used to quickly classify bacteria into two broad categories according to their type of cell wall. The Gram stain ...

, fungi, and protozoa including ''

Tetrahymena pyriformis ''Tetrahymena pyriformis'' is a species of Ciliophora The ciliates are a group of alveolates characterized by the presence of hair-like organelles called cilia, which are identical in structure to eukaryotic flagella, but are in general sho ...

''.

Structure

Macbecins have an unusual

macrocyclic Macrocycles are often described as molecules and ions containing a ring of twelve or more atoms. Classical examples include the crown ethers, calixarenes, porphyrins, and cyclodextrins. Macrocycles describe a large, mature area of chemistry. ...

lactam A lactam is a Cyclic compound, cyclic amide, formally derived from an amino alkanoic acid through cyclization reactions. The term is a portmanteau of the words ''lactone'' + ''amide''. Nomenclature Greek_alphabet#Letters, Greek prefixes in alpha ...

structure. The two variants, macbecin I and II, correspond to the oxidized

1,4-benzoquinone 1,4-Benzoquinone, commonly known as ''para''-quinone, is a chemical compound with the chemical formula, formula C6H4O2. In a pure state, it forms bright-yellow crystals with a characteristic irritating odor, resembling that of chlorine, bleach, ...

and reduced

hydroquinone Hydroquinone, also known as benzene-1,4-diol or quinol, is an aromatic organic compound that is a type of phenol, a derivative of benzene, having the chemical formula C6H4(OH)2. It has two hydroxyl groups bonded to a benzene ring in a ''para' ...

, respectively.

Mechanism of action

Macbecins mechanism of action is in part due to

heat shock protein Heat shock proteins (HSPs) are a family of proteins produced by cells in response to exposure to stressful conditions. They were first described in relation to heat shock, but are now known to also be expressed during other stresses including ex ...

Hsp90 Hsp90 (heat shock protein 90) is a chaperone (protein), chaperone protein that assists other proteins to protein folding, fold properly, stabilizes proteins against heat stress, and aids in protein degradation. It also stabilizes a number of ...

protein inhibition.

References

External links

* * {{MeshName, Macbecin+II Ansamycins Carbamates 1,4-Benzoquinones Lactams Ethers Heterocyclic compounds with 2 rings