Biological characterization of a novel mammalian antimicrobial peptide

• Published in: Biochimica et biophysica acta Vol. 1425; no. 2; pp. 361 - 368
• Main Authors: Gennaro, Renato, Scocchi, Marco, Merluzzi, Laura, Zanetti, Margherita
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 23.10.1998
• Subjects: Amino Acid Sequence; Animals; Anti-Bacterial Agents - chemistry; Antimicrobial peptide; Cathelicidin; Cattle; Circular Dichroism; Cow; Escherichia coli - drug effects; Male; Membrane permeabilization; Microbial Sensitivity Tests; Molecular Sequence Data; Neutrophils - metabolism; Proteins - analysis; Proteins - chemistry; Proteins - genetics; Sequence Alignment; Spleen - metabolism; Testis - metabolism; α-Helical peptide; Cathelicidin; Membrane permeabilization; Cow; α-Helical peptide; Antimicrobial peptide
• ISSN: 0304-4165; 0006-3002; 1872-8006
• DOI: 10.1016/S0304-4165(98)00087-7

A putative antimicrobial peptide of 34 residues was recently deduced from a bovine cathelicidin gene sequence and named BMAP-34. A peptide based on the deduced sequence was chemically synthesized and used to study the localization, structure and biological activities of BMAP-34. A Western blot analysis using antibodies raised to the synthetic peptide showed that BMAP-34 is stored as proform in the cytoplasmic granules of bovine neutrophils. CD spectroscopy indicates that the peptide assumes an amphipathic α-helical conformation, as also predicted by secondary structure analysis. The peptide exerts a broad spectrum antimicrobial activity against both Gram-negative and Gram-positive organisms, and is not active against eukaryotic cells. When tested on Escherichia coli ML-35, the kinetics of bacterial killing and of inner membrane permeabilization are slower than those observed for other α-helical peptides derived from cathelicidins.