Tetracyclin

From ArticleWorld

The credit for discovering tetracycline goes to Dr. Lloyd Conover in the R&D labs of Pfizer. It is marketed under different names. Produced by the streptomyces bacterium, tetracycline is a broad-spectrum antibiotic. It is the raw material or the mother compound used to produce several semi-synthetic forms (derivatives). The forms are grouped under the family known as the Tetracycline antibiotics.

History

Lloyd Conover discovered this bacteriostatin, tetracycline in 1952. By 1955, within three years of its discovery, it was patented and was being prescribed as a broad-spectrum antibiotic. The patent and usage were questioned and the inventors were taken to court. The ruling did not happen until 1982, but then the invention, usage and the patent for tetracycline were upheld by the court.

Mechanism, structural details, resistance

It is important to realize that tetracycline is a bacteriostatin. It prevents the multiplication of bacteria by preventing translation. (Translation, oversimplified, is the synthesis of protein.) The binding of amino-acyl tRNA to the site of the ribosome is one of the major steps in translation. It competes with the amino-acyl tRNA and by binding to the 30S sub-unit of the ribosome, it prevents translation. Though the binding is reversible, it is enough for the body to fight the infection because it does not have to deal with an ever-increasing number of bacteria.

Its IUPAC name is 2-(amino-hydroxy-methylidene)-4-dimethylamino-6, 10,11,12a-tetrahydroxy-6-methyl-4, 4a, 5,5a-tetrahydrotetracene-1, and 3,12-trione. Its molecular weight is Molecular weight 444.435 g/mole. (Of course, its synthetic derivatives are a different matter.) Its chemical formula is C22H24N2O8.

Bacteria acquire resistance to tetracycline via two mechanisms

• Efflux: A membrane protein is encoded to actively pump tetracycline out. This is observed in the plasmid pBR322, which comes with resistance genes.

• Ribosomal protection: To allow amino acyl tRNA to bind to the 30s sub-unit, the bacteria encodes a protein that bind to the ribosome before tetracycline can bind.

The significance of Tetracycline

Tetracycline is supposed to be one of the most important discoveries of the 20th century. Tetracycline cured infections true, but with the development of semi-synthetic derivatives, it set a trend. It led to the development of a number of antibiotics that were derivatives. Today, after forty years of its patent, it is still being used extensively. One of its common uses is to treat acne.