Biological characterization of a novel mammalian antimicrobial peptide.
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 alpha-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 alpha-helical peptides derived from cathelicidins.
Gennaro
R
R
Dipartimento di Biochimica, Biofisica e Chimica delle Macromolecole, Università di Trieste, I-34127 Trieste, Italy.
Scocchi
M
M
Merluzzi
L
L
Zanetti
M
M
D000595:Amino Acid Sequence; D000818:Animals; D000900:Anti-Bacterial Agents / Q000737:chemistry*; D002417:Cattle; D002942:Circular Dichroism; D004926:Escherichia coli / Q000187:drug effects; D008297:Male; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D009504:Neutrophils / Q000378:metabolism; D011506:Proteins / Q000032:analysis / Q000737:chemistry* / Q000235:genetics*; D016415:Sequence Alignment; D013154:Spleen / Q000378:metabolism; D013737:Testis / Q000378:metabolism
D000900:Anti-Bacterial Agents; C109686:CATHL7 protein, Bos taurus; D011506:Proteins