- Polymyxin B
drugbox
IUPAC_name =N- [4-amino-1- [1- [4-amino-1-oxo-1- [6,9,18-tris(2-aminoethyl)-15-benzyl-3-(1-hydroxyethyl)-12-(2-methylpropyl)-2,5,8,11,14,17,20-heptaoxo-1,4,7,10,13,16,19-heptazacyclotricos-21-yl] amino] butan-2-yl] amino] -3-hydroxy-1-oxobutan-2-yl] amino] -1-oxobutan-2-yl] -6-methyloctanamide
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CAS_number = 1405-20-5
ATC_prefix = A07
ATC_suffix = AA05
ATC_supplemental = ATC|J01|XB02, ATC|S01|AA18, ATC|S02|AA11, ATC|S03|AA03
PubChem = 5702105
DrugBank = APRD01190
C=56 | H=100 | N=16 | O=17 | S=1
molecular_weight = 1301.56 g/mol
bioavailability =
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metabolism =
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routes_of_administration =Polymyxin B is an antibiotic primarily used for resistant
gram negative infections. Polymyxins bind to the cell membrane and alter its structure making it more permeable. The resulting water uptake leads to cell death. They are cationic, basic proteins that act like detergents. Side effects include neurotoxicity and acute renal tubular necrosis.# Family of polypeptides with attached fatty acid;
cationic detergent at physiological pH, both hydrophilic and hydrophobic properties
# Bactericidal forgram-negative ; little to no effect ongram-positive since cell wall is too thick to permit access to membraneMechanism of action
# Alters cytoplasmic membrane permeability by binding to a negatively charged site in the lipopolysaccharide layer which has an electrostatic attraction for the positively charged amino groups in the cyclic peptide portion
# Fatty acid portion dissolves in hydrophobic region of membrane and disrupts membrane integrity
# Leakage of cellular molecules, inhibition of cellular respiration
# Binds and inactivates endotoxincite journal |author=Cardoso LS, Araujo MI, Góes AM, Pacífico LG, Oliveira RR, Oliveira SC |title=Polymyxin B as inhibitor of LPS contamination of Schistosoma mansoni recombinant proteins in human cytokine analysis |journal=Microb. Cell Fact. |volume=6 |issue= |pages=1 |year=2007 |pmid=17201926 |pmc=1766364 |doi=10.1186/1475-2859-6-1 |url=http://www.microbialcellfactories.com/content/6//1]
# Relative absence of selective toxicity: nonspecific for cell membranes of any type, highly toxicResearch application
# In addition to its antibiotic function, polymix B has been used to clear endotoxin contamination in reagents.
References
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