Interactions between Salmonella typhimurium lipopolysaccharide and the antimicrobial peptide, magainin 2 amide.
Effects of magainin 2 amide on the phase behavior of Salmonella typhimurium lipopolysaccharide were characterized by FT-IR spectroscopy. This antimicrobial cationic peptide disorders the lipopolysaccharide at molecular ratios of lipopolysaccharide to magainin greater than 4, and can induce a temperature-dependent structural reorientation. The nature of the five phosphate groups of lipopolysaccharide was determined by 31P NMR spectroscopy. At pH 7.4, the net charge on the phosphates is -7. Lipopolysaccharide undoubtedly plays an important role in modulating the interactions of magainin with the gram-negative cell envelope and may act as a molecular sponge to protect the plasma membrane.
Rana
F R
FR
Department of Chemistry, Ohio University, Athens 45701.
Sultany
C M
CM
Blazyk
J
J
D000818:Animals; D023181:Antimicrobial Cationic Peptides; D004563:Electrochemistry; D006863:Hydrogen-Ion Concentration; D008070:Lipopolysaccharides / Q000032:analysis / Q000378:metabolism; D054806:Magainins; D009682:Magnetic Resonance Spectroscopy; D010455:Peptides / Q000378:metabolism / Q000494:pharmacology*; D010710:Phosphates / Q000032:analysis; D012486:Salmonella typhimurium / Q000032:analysis*; D013055:Spectrophotometry, Infrared; D013696:Temperature; D029867:Xenopus Proteins; D014982:Xenopus laevis
D023181:Antimicrobial Cationic Peptides; D008070:Lipopolysaccharides; D054806:Magainins; D010455:Peptides; D010710:Phosphates; D029867:Xenopus Proteins; C053301:magainin 2 peptide, Xenopus