Chloramphenicol

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[[Image:{{{image\|Chloramphenicol.png}}}\|{{{width\|220}}}px\|Chloramphenicol chemical structure]] Chloramphenicol
IUPAC name
CAS number 56-75-7	}}}
PubChem 298	DrugBank EXPT00942
Chemical formula	{{carbon
Molecular weight	{{{molecular_weight}}}
Bioavailability	{{{bioavailability}}}
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Elimination half-life	{{{elimination_half-life}}}
Excretion	{{{excretion}}}
Pregnancy category	{{{pregnancy_category}}}
Legal status	{{{legal_status}}}
Routes of administration	{{{routes_of_administration}}}

H{{#if:{{{1|}}}|₁₂}}N{{#if:{{{1|}}}|₂|}}O{{#if:{{{1|}}}|₅|}}Cl{{#if:{{{1|}}}|₂|}} | molecular_weight = 323.132 | bioavailability= ? | metabolism = ? | elimination_half-life=? | excretion = ? | pregnancy_category = C (A topical) | legal_status = POM | routes_of_administration= IV, O, topical }} Chloramphenicol (or 2,2-dichlor-N-[(aR,bR)-b-hydroxy-a-hydroxymethyl-4-nitrophenethyl]acetamide) is an antibiotic that was derived from the bacterium Streptomyces venezuelae and is now produced synthetically. Chloramphenicol is effective against a wide variety of microorganisms, but due to serious side-effects (e.g., damage to the bone marrow, including aplastic anemia) in humans, it is usually reserved for the treatment of serious and life-threatening infections (e.g., typhoid fever).

Regardless of serious side-effects, the WHO advocates its use in many third world countries for pediatric treatment in the absence of cheaper alternatives. It is used in treatment of cholera, as it destroys the vibrios and decreases the diarrhea. It is effective against tetracycline-resistant vibrios.

It is also used in eye drops or ointment, commonly sold under the name of Chlorsig, to treat bacterial conjunctivitis.

1 Mechanism and Resistance
2 Codes
3 External links
4 References

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Mechanism and Resistance

Chloramphenicol stops bacterial growth by inhibiting the enzyme peptidyl transferase, which inhibits ribosomal activity and protein synthesis by preventing the binding of amino acyl-tRNA to the A site on the 50S subunit <ref>Petska, S. (1971). Inhibitors of ribosome functions. Annual Review of Microbiology 25:1580.</ref>. Resistance to chloramphenicol is conferred by the cat-gene. This gene codes for an enzyme called "chloramphenicol acetyltransferase" which inactivates chloramphenicol by covalently linking one or two acetyl groups, derived from acetyl-S-coenzyme A, to the hydroxyl groups on the chloramphenicol molecule. The acetylation prevents chloramphenicol from binding to the ribosome.

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