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Updated: Jul 28, 2026

Purification and Visualization of Lipopolysaccharide from Gram-negative Bacteria by Hot Aqueous-phenol Extraction
Published on: May 28, 2012
All-D-cecropin B: synthesis, conformation, lipopolysaccharide binding, and antibacterial activity
J M Bland1, A J De Lucca, T J Jacks
1United States Department of Agriculture, Agricultural Research Service, Southern Regional Research Center, New Orleans, LA 70179, USA.
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.
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