title: The antimicrobial peptides lactoferricin B and magainin 2 cross over the bacterial cytoplasmic membrane and reside in the cytoplasm.
abstract: The localization of immunolabelled antimicrobial peptides was studied using transmission electron microscopy. Staphylococcus aureus and Escherichia coli were exposed to lactoferricin B (17-41), lactoferricin B (17-31) and D-lactoferricin B (17-31). E. coli was also exposed to cecropin P1 and magainin 2. The lactoferricins were found in the cytoplasm of both bacteria. In S. aureus the amount of cytoplasmic lactoferricin B (17-41) was time- and concentration-dependent, reaching a maximum within 30 min. Cecropin P1 was confined to the cell wall, while magainin 2 was found in the cytoplasm of E. coli. The finding of intracellularly localized magainin is not reported previously.
authors.affiliation: Department of Medical Microbiology, University Hospital Tromsø, Norway. mlabhh@rito.no
authors.forename: H H
authors.initials: HH
authors.lastname: Haukland
authors.forename: H
authors.initials: H
authors.lastname: Ulvatne
authors.forename: K
authors.initials: K
authors.lastname: Sandvik
authors.forename: L H
authors.initials: LH
authors.lastname: Vorland
mesh_terms: D023181:Antimicrobial Cationic Peptides / Q000378:metabolism* / Q000494:pharmacology; D002462:Cell Membrane / Q000378:metabolism*; D003593:Cytoplasm / Q000378:metabolism; D004926:Escherichia coli / Q000187:drug effects / Q000378:metabolism*; D007150:Immunohistochemistry; D007781:Lactoferrin / Q000031:analogs & derivatives* / Q000378:metabolism* / Q000494:pharmacology; D054806:Magainins; D008826:Microbial Sensitivity Tests; D013211:Staphylococcus aureus / Q000187:drug effects / Q000378:metabolism*; D029867:Xenopus Proteins
chemical_list: D023181:Antimicrobial Cationic Peptides; D054806:Magainins; D029867:Xenopus Proteins; C053301:magainin 2 peptide, Xenopus; C082171:lactoferricin B; D007781:Lactoferrin