Viridicatumtoxin B is a
fungus-derived
tetracycline-like
antibiotic
An antibiotic is a type of antimicrobial substance active against bacteria. It is the most important type of antibacterial agent for fighting bacterial infections, and antibiotic medications are widely used in the treatment and prevention of ...
discovered in 2008. It was isolated from small amounts of
penicillium fungi. A synthetic structure matching that of natural viridicatumtoxin B makes possible synthetic variants that match or surpass its antibiotic potency.
Analogs lacking a
hydroxyl group
In chemistry, a hydroxy or hydroxyl group is a functional group with the chemical formula and composed of one oxygen atom covalently bonded to one hydrogen atom. In organic chemistry, alcohols and carboxylic acids contain one or more hydroxy g ...
were even more effective than the original against
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.
Gram-positive bact ...
.
Concerns about solubility, biodegradation, availability and other issues must be resolved before
clinical development
Drug development is the process of bringing a new pharmaceutical drug to the market once a lead compound has been identified through the process of drug discovery. It includes preclinical research on microorganisms and animals, filing for regu ...
begins.
History
The substance was first isolated from the
mycelium of liquid
fermentation
Fermentation is a metabolic process that produces chemical changes in organic substrates through the action of enzymes. In biochemistry, it is narrowly defined as the extraction of energy from carbohydrates in the absence of oxygen. In food ...
cultures of ''
Penicillium''
species FR11.
[
]
Structure
Based on mass spectrometry
Mass spectrometry (MS) is an analytical technique that is used to measure the mass-to-charge ratio of ions. The results are presented as a ''mass spectrum'', a plot of intensity as a function of the mass-to-charge ratio. Mass spectrometry is use ...
and nuclear magnetic resonance data, the substance was originally thought to be the 11a',12'- epoxide,[ but the structure was later revised.]
Effects
Viridicatumtoxin B inhibited the growth of ''Staphylococcus aureus
''Staphylococcus aureus'' is a Gram-positive spherically shaped bacterium, a member of the Bacillota, and is a usual member of the microbiota of the body, frequently found in the upper respiratory tract and on the skin. It is often positive ...
'', including methicillin resistant ''S. aureus'' and quinolone
Quinolone may refer to:
* 2-Quinolone
* 4-Quinolone
* Quinolone antibiotic
A quinolone antibiotic is a member of a large group of broad-spectrum bacteriocidals that share a bicyclic core structure related to the substance 4-quinolone. They ...
-resistant ''S. aureus'' with a minimum inhibitory concentration of 0.5 μg/ml. That effect is similar to that of vancomycin, but 8 to 64 times greater than that of tetracycline.
Total synthesis
A complete total synthesis of viridicatumtoxin B, in racemic form, was completed in 2013 by the group of K. C. Nicolaou
Kyriacos Costa Nicolaou ( el, Κυριάκος Κ. Νικολάου; born July 5, 1946) is a Cypriot-American chemist known for his research in the area of natural products total synthesis. He is currently Harry C. and Olga K. Wiess Professor of ...
.
See also
* Viridicatumtoxin A
References
Tetracycline antibiotics
Spiro compounds
Cyclohexenes
{{antibiotic-stub