Macbecin belongs to the ansamycin

Ansamycin

Ansamycins is a family of secondary metabolites that show antimicrobial activity against many gram-positive and some gram-negative bacteria and includes various compounds, among which: streptovaricins and rifamycins...

 family of 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...

s and was first isolated from actinomycete bacteria. Macbecin possesses potent antitumor

Chemotherapy

Chemotherapy is the treatment of cancer with an antineoplastic drug or with a combination of such drugs into a standardized treatment regimen....

 properties.

Structure

Macbecin has an unusual macrocyclic

Macrocycle

A macrocycle is, as defined by IUPAC, "a cyclic macromolecule or a macromolecular cyclic portion of a molecule." In the chemical literature, organic chemists may consider any molecule containing a ring of nine or more atoms to be a macrocycle...

 lactam

Lactam

A lactam is a cyclic amide. Prefixes indicate how many carbon atoms are present in the ring: β-lactam , γ-lactam , δ-lactam...

 structure. There are two variants Macbecin I and II which correspond to the oxidized 1,4-benzoquinone

1,4-Benzoquinone

1,4-Benzoquinone, commonly known as para-quinone, is a chemical compound with the formula C6H4O2. In a pure state, it forms bright-yellow crystals with a characteristic irritating odor, resembling that of chlorine, bleach, and hot plastic. Impure samples are often dark-colored due to the presence...

 and reduced hydroquinone

Hydroquinone

Hydroquinone, also benzene-1,4-diol or quinol, is an aromatic organic compound that is a type of phenol, having the chemical formula C6H42. Its chemical structure, shown in the table at right, has two hydroxyl groups bonded to a benzene ring in a para position. It is a white granular solid...

 respectively.

Mechanism of action

Macbecins mechanism of action is in part due to heat shock protein

Heat shock protein

Heat shock proteins are a class of functionally related proteins involved in the folding and unfolding of other proteins. Their expression is increased when cells are exposed to elevated temperatures or other stress. This increase in expression is transcriptionally regulated...

 Hsp90

Hsp90

Hsp90 is a molecular chaperone and is one of the most abundant proteins expressed in cells. It is a member of the heat shock protein family, which is upregulated in response to stress...

protein inhibition.