| 
  • If you are citizen of an European Union member nation, you may not use this service unless you are at least 16 years old.

  • You already know Dokkio is an AI-powered assistant to organize & manage your digital files & messages. Very soon, Dokkio will support Outlook as well as One Drive. Check it out today!

View
 

Tyrocidine

This version was saved 16 years, 10 months ago View current version     Page history
Saved by PBworks
on May 13, 2007 at 12:00:31 am
 

Tyrocidine

 

Tyrocidine is a cyclic decapeptide antibiotic that is produced by Bacillus brevis, a Gram-positive aerobic spore-forming bacillus commonly found in soil, air, water, and decaying matter. Tyrocidine is in fact a mixture of four cyclic decapeptides, tyrocidines A, B, C, and D. Tyrocidine is a constituent of tyrothricin, a mixture of polypeptide antibiotics.

 

 

Contents:

1. History

2. Structure

3. Biosynthesis

4. Mechanism of action

5. Clinical use

 

History


Tyrocidine is a constituent of tyrothricin, which was originally isolated by Rene Dubos in 1939, and was the first commercially produced antibiotic.

 

Structure


 

Biosynthesis


 

The cyclic decapeptide antibiotic tyrocidine is produced by Bacillus brevis on an enzyme complex comprising three peptide synthetases, TycA, TycB, and TycC (tyrocidine synthetases 1, 2, and 3), via the nonribosomal pathway. Nonribosomal pathways are characterized by substrates that are not restricted to the 20 proteinogenic amino acids; that is to say, the amino acids that are found in proteins and that are coded for in the standard genetic code. Products synthesized using this pathway can incorporate nonproteinogenic amino acids, such as hydroxy-, D-, and N-methylated amino acids.

 

 

 

1. Amino acids are first activated by conversion into AMP esters, which then bind to the enzyme through thioester linkages.

 

 

 

2.

 

 

Mechanism of action


 

Tyrocidine kills bacteria by interacting with their cytoplasmic membrane and causing leakage of their intracellular content. It also affects intracellular membranes such as those of mitochondria.

 

 

 

 

 

Comments (0)

You don't have permission to comment on this page.