Description
PolymyxinBisamixtureofpolymyxinB1,B2,B3andB1-1sulfates;polymyxinBisacationiclipidoligopeptidederivedfromBacilluspolymyxathatdisplaysantibacterialactivityagainstallgram-negativebacteriaexceptspeciesofProteus.PolymyxinBkillsbothproliferativeandquiescentcellsinvitro.PolymyxinBinhibitscellularrespirationbyinhibitingtypeIINADH-quinoneoxidoreductaseactivity.Thiscompoundalsoinducesaggregationoflipopolysaccharide(LPS)inbacterialcellmembranes,alteringmembranepotentialandcausingleakageofcellularcomponents.PolymyxinBhasbeenusedtotreatsepticshockinducedbyLPSofgram-negativebacteria,preventingLPS-inducedcaspaseactivity,Fasexpression,Bax/Bcl-2ratioalteration,andapoptosis.