Tetracycline

( 4S, 4aS, 5as, 6S, 12aS ) - 4 - (dimethylamino) -3,6,10,12,12 a- pentahydroxy -6-methyl -1 ,11- dioxo- 1, 4,4 a, 5,5 a, 6,11,12 a- octahydrotetracen -2- carboxamide (IUPAC)

• A01AB13
• D06AA04
• J01AA07
• S01AA09
• S02AA08
• S03AA02

Yellow solid

Antibiotic

Fixed

172 ° C.

• Poorly in water ( 231 mg · l-1 at 25 ° C)
• Insoluble in ethanol, acetone, chloroform and ethyl acetate
• Poor in petroleum ether

Attention

678 mg · kg -1 ( LD50, mouse, oral)

Template: Infobox chemical / molecular formula search available

Tetracycline is an antibiotic and belongs to the group of tetracyclines. Tetracycline is a broad spectrum antibiotic, which is produced by Streptomyces ( Streptomyces aureofaciens ) and is used against many bacterial infections. It is often used for acne.

Mechanism of action

Preventing the addition of aminoacyl-tRNA to the rRNA in the 30S subunit of the bacterial ribosome. Thus, the translation, and ultimately protein synthesis is stopped.

Toxicity may be due to inactivation of the 30S ribosomes present in the eukaryotic host cell mitochondria.

History

The tetracyclines are a large family of antibiotics, which have been described by Benjamin Minge Duggar in 1948. Tetracycline was then discovered by Lloyd Conover in the research department of Pfizer. The patent for tetracycline was approved in 1955. However, in the 1990s, tetracyclines was discovered in the Nubian mummies, so the beer brewed at that time could have been a source of tetracycline. Tetracycline acts on many gram-negative, gram-positive bacteria and not dyeable by Gram bacteriostatic.

Contraindications and side effects

• Can stain developing teeth (even when taken during pregnancy ), see tetracycline teeth
• Is mainly of aluminum, iron and calcium inactivated by chelation, so no taking with antacids, iron supplements or dairy products
• Phototoxic, so no strong sunlight under tetracycline
• Not taken during pregnancy
• Not for children under 8 years
• No income at Tetracyclinallergie

Indication

• Respiratory infections (such as atypical pneumonia, the drug of choice only when Q fever )
• Infections of the genitourinary system (about: prostatitis )
• Skin infections (such as: Acne vulgaris)
• Infections of the intestine (about: Cholera )
• But also plague, brucellosis and tularemia etc.

Other Applications

Because tetracycline is included in the bone, it is used as a marker of bone growth in human biopsies. The presence of tetracycline in the bone is detected by fluorescence. In the tetracycline gene technology is used in the transcription activation or deactivation employed in the developed Hermann Bujard Tet system. Thus genes can be selectively activated and their function are studied.

Mechanisms of resistance

From faecal bacteria isolated are more than 80% resistant to tetracycline. This is due to the following mechanisms:

• Various resistance plasmids encoding a tetracycline efflux pump that transports the antibiotic is active ( ie ATP hydrolysis ) from the cell
• Protecting ribosomes as protein Tet (O) can cause drug resistance by actively removing tetracycline ( under GTP hydrolysis ) from the ribosome.
• Genomic tetracycline resistance come about by mutations in the site of action of the antibiotic, the 16S rRNA.

Pharmacokinetics

The oral bioavailability while avoiding prior food intake is provided with 60 to 80 %. The plasma half-life is 8.5 hours, whereby the excretion occurs mainly via the kidneys, as is reabsorbed in the bile secreted tetracycline in large part from the intestine, it is subject to the enterohepatic circulation. The plasma protein binding is 50%.

Trade names

Actisite - Dental ( A) Imex (D) Tefilin (D), as well as a generic (D)

Fluorex Plus ( A), Mysteclin (D, A)

Cyclutrin, Tetrabiotic, tetra, Utroletten

Chemical Properties

Tetracycline hydrochloride, a yellow crystalline hygroscopic powder turns brown after direct contact with sun rays and during storage in moist air.