Tetracycline

This article deals with the specific antibiotic called tetracycline. For the group of antibiotics known as the tetracyclines, see tetracycline antibiotics.
Tetracycline
Systematic (IUPAC) name
2-(amino-hydroxy-methylidene)-4-dimethylamino-
6,10,11,12a-tetrahydroxy-6-methyl-4,4a,5,
5a-tetrahydrotetracene-1,3,12-trione
OR
4-(dimethylamino)-1,4,4a,5,5a,6,11,12a-octahydro-
3,6,10,12,12a-pentahydroxy-
1,11-dioxo-naphthacene-2-carboxamide
OR
(4S,6S,12aS)-4-(dimethylamino)- 3,6,10,12,12a-pentahydroxy- 6-methyl-1,11-dioxo-1,4,4a,5,5a,6,11,12a- octahydrotetracene-2-carboxamide
Identifiers
CAS number 60-54-8
64-75-5 (hydrochloride)
ATC code A01AB13 D06AA04 J01AA07 S01AA09 S02AA08 S03AA02 QG01AA90 QG51AA02 QJ51AA07
PubChem CID 643969
DrugBank DB00759
ChemSpider 10257122
Chemical data
Formula C22H24N2O8 
Mol. mass 444.435 g/mol
Pharmacokinetic data
Bioavailability 60-80% Oral, while fasting
<40% Intramuscular
Metabolism Not metabolised
Half-life 6-11 hours
Excretion Fecal and Renal
Therapeutic considerations
Pregnancy cat. D(AU) D(US)
Legal status Prescription only
Routes oral, topical (skin & eye), im, iv
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Tetracycline (INN) (pronounced /ˌtɛtrəˈsaɪkliːn/) is a broad-spectrum polyketide antibiotic produced by the Streptomyces genus of Actinobacteria, indicated for use against many bacterial infections. It is a protein synthesis inhibitor. It is commonly used to treat acne today, and, more recently, rosacea, and played a historical role in reducing the incidence of mortality because of cholera. It is sold under the brand names Sumycin, Terramycin, Tetracyn, and Panmycin, among others. Actisite is a thread-like fiber form, used in dental applications. It is also used to produce several semi-synthetic derivatives, which together are known as the tetracycline antibiotics.

Contents

Mechanism of action

Tetracycline antiporter system

Tetracyclines work by binding the 30S ribosomal subunit and through an interaction with 16S rRNA, they prevent the docking of amino-acylated tRNA. [1]

Resistance to tetracyclines can arise through drug efflux, ribosomal protection proteins, 16S rRNA mutation, and drug inactivation through the action of a monooxygenase.[2]

History

The tetracyclines are a large family of antibiotics that were discovered as natural products by Benjamin Minge Duggar and first described in 1948.[3] Under Yellapragada Subbarao, Benjamin Duggar made his discovery of the world's first tetracycline antibiotic, Aureomycin, in 1945.

In 1950, Harvard Professor Robert Woodward determined the chemical structure of Terramycin, the brand name for a member of the tetracycline family; the patent [1] protection for its fermentation and production was also first issued in 1950. A research team of seven scientists at Pfizer [2], in collaboration with Woodward, participated in the two-year research leading to the discovery [3].

Nubian mummies have been studied in the 1990s and were found to contain significant levels of tetracycline; there is evidence that the beer brewed at the time could have been the source.[4] Tetracycline sparked the development of many chemically altered antibiotics and in doing so has proved to be one of the most important discoveries made in the field of antibiotics. It is used to treat many gram-positive and gram-negative bacteria and some protozoa. It, like some other antibiotics, is also used in the treatment of acne.

Cautions, contraindications, side-effects

Are as those of the tetracycline antibiotics group:

Indication

It is first-line therapy for Rocky Mountain spotted fever (Rickettsia), Q fever (Coxiella), Psittacosis and Lymphogranuloma venereum (Chlamydia), and to eradicate nasal carriage of meningococci. Tetracycline tablets were used in the plague outbreak in India in 1992. [6]

Doxycycline is also one (of many) recommended drugs for chemoprophylatic treatment of malaria in travels to areas of the world where malaria is endemic. [7]

Other uses

Since tetracycline is absorbed into bone, it is used as a marker of bone growth for biopsies in humans. Tetracycline labeling is used to determine the amount of bone growth within a certain period of time, usually a period of approximately 21 days. Tetracycline is incorporated into mineralizing bone and can be detected by its fluorescence.[8] In double tetracycline labeling, a second dose is given 11-14 days after the first dose, and the amount of bone formed during that interval can be calculated by measuring the distance between the two fluorescent labels.[9]

Tetracycline is also used as a biomarker in wildlife to detect consumption of medicine- or vaccine-containing baits.[10]

In genetic engineering, tetracycline is used in transcriptional activation. Tetracycline is also one of the antibiotics used to treat ulcers caused by bacterial infections. In cancer research at Harvard Medical School, tetracycline has been used to reliably cause regression of advanced stages of leukemia in mice, by placing it in their drinking water.[11]

Cell culture

Tetracycline is used in cell biology as selective agent in cell culture systems. It is toxic to prokaryotic and eukaryotic cells and selects for cells harboring the bacterial tetr gene, which encodes a 399-amino acid membrane-associated protein. This protein actively exports tetracycline out of the cell, rendering cells harboring this gene more resistant to the drug. The yellow crystalline powder can be dissolved in water (20 mg/ml) or ethanol (5 mg/ml) and is routinely used at 10 mg/l in cell culture. In cell culture at 37 °C, it is stable for 4 days.

Notes

  1. Alekshun, M. N. & Levy, S. B. Molecular Mechanisms of Antibacterial Multidrug Resistance. Cell, 128, 1037-1050 (2007).
  2. Zakeri, B. & Wright, G. D. Chemical biology of tetracycline antibiotics. Biochem. Cell Biol. 86, 124-136 (2008).
  3. Klajn, Rafal, Chemistry and chemical biology of tetracyclines, retrieved 20 June 2007.
  4. George Armelagos (May, 2000). "Take Two Beers and Call Me in 1,600 Years - use of tetracycline by Nubians and Ancient Egyptians". American Museum of Natural History. http://www.findarticles.com/p/articles/mi_m1134/is_4_109/ai_62324477. Retrieved 2007-12-19. 
  5. kidsgrowth.org --> Drugs and Other Substances in Breast Milk Retrieved on June 19, 2009
  6. Lippincott's Illustrated Reviews: Pharmacology, 4th ed. Harvery RA, Champe, PC. Lippincott, Williams & Wilkins, 2009
  7. http://wwwn.cdc.gov/TRAVEL/yellowBookCh4-Malaria.aspx
  8. Mayton CA. Tetracycline labeling of bone
  9. The Johns Hopkins Medical Institutions. > Tetracycline Labeling Last updated 1/8/2001.
  10. Olson CA, et al. Bait ingestion by free-ranging raccoons and nontarget species in an oral rabies vaccine field trial in Florida. J Wildl Dis. 2000 Oct;36(4):734-43.
  11. William J. Cromie (February 10, 2000). "Researchers Switch Cancer Off and On -- In Mice". http://www.hno.harvard.edu/gazette/2000/02.10/leukemia.html. Retrieved 2008-10-25.