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Lentivirus lytic peptide 1 perturbs both outer and inner membranes of Serratia marcescens

Shruti M Phadke1, Vanja Lazarevic, Caroline C Bahr

  • 1Department of Pediatrics, Children's Hospital of Pittsburgh, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15261, USA.

Antimicrobial Agents and Chemotherapy
|May 23, 2002
PubMed

Insights

Bis-lentivirus lytic protein 1 (Bis-LLP1) and polymyxin B show similar antibacterial effects against Serratia marcescens. However, Bis-LLP1 targets both outer and cytoplasmic membranes, unlike polymyxin B which only affects the outer membrane, indicating distinct antimicrobial mechanisms.

Area of Science:

  • Microbiology
  • Biochemistry
  • Molecular Biology

Background:

  • Antimicrobial peptides are crucial in combating bacterial infections.
  • Serratia marcescens is an opportunistic pathogen requiring effective treatment strategies.
  • Understanding the mechanisms of action of antimicrobial agents is vital for developing new therapies.

Purpose of the Study:

  • To compare the antibacterial activity and mechanisms of action of Bis-lentivirus lytic protein 1 (Bis-LLP1) and polymyxin B against Serratia marcescens.

Main Methods:

  • Comparative analysis of killing activities against Serratia marcescens.
  • Electron microscopy to visualize bacterial membrane interactions.
  • Biochemical probes to confirm membrane targeting.

Main Results:

  • Bis-LLP1 and polymyxin B demonstrated comparable killing efficacy against Serratia marcescens.
  • Electron microscopy revealed Bis-LLP1 interacts with both outer and cytoplasmic membranes.
  • Polymyxin B was observed to affect only the outer membrane of Serratia marcescens.
  • Biochemical probes corroborated the distinct membrane interaction sites.

Conclusions:

  • Bis-lentivirus lytic protein 1 and polymyxin B possess different mechanisms of action against Serratia marcescens.
  • Bis-LLP1's dual membrane targeting suggests a broader spectrum or different mode of action compared to polymyxin B.

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