All-D-cecropin B: synthesis, conformation, lipopolysaccharide binding, and antibacterial activity

Mol Cell Biochem. 2001 Feb;218(1-2):105-11. doi: 10.1023/a:1007293816634.

Abstract

Cecropin B (LCB) is a natural peptide with antibacterial and antifungal properties. The enantiomer of LCB, containing all-D amino acids (DCB), was synthesized to examine its antibacterial and binding properties. The conformation of DCB was compared to its enantiomer by circular dichroism. Both the L- and D-peptides showed an identical induction of alpha-helical secondary structure. However, binding studies between Lipopolysaccharide (LPS) and DCB or LCB were studied with a dimethylmethylene blue spectrophotometric assay, showing the two enantiomeric peptides differed in their interaction with LPS. Antibacterial activity of DCB was determined against three Gram-negative bacteria, Pantoea agglomerans (ATCC 27996), Escherichia coli (ATCC 8739), and Pseudomonas aeruginosa (ATCC 17648), giving comparable results to LCB.

MeSH terms

  • Chromatography, High Pressure Liquid
  • Circular Dichroism
  • Escherichia coli / drug effects*
  • Gram-Negative Bacteria / drug effects*
  • In Vitro Techniques
  • Insect Proteins / chemistry*
  • Insect Proteins / metabolism
  • Insect Proteins / pharmacology*
  • Lipopolysaccharides / metabolism*
  • Lipopolysaccharides / pharmacology
  • Microbial Sensitivity Tests
  • Peptide Biosynthesis
  • Protein Binding
  • Protein Conformation
  • Pseudomonas aeruginosa / drug effects*
  • Stereoisomerism

Substances

  • Insect Proteins
  • Lipopolysaccharides
  • cecropin B protein, Insecta