A polyalanine peptide derived from polar fish with anti-infectious activities

July 28, 2017


A polyalanine peptide derived from polar fish with anti-infectious activities


Marlon H. Cardoso, Suzana M. Ribeiro, Diego O. Nolasco, César de la Fuente-Núñez, Mário R. Felício, Sónia Gonçalves, Carolina O. Matos, Luciano M. Liao, Nuno C. Santos, Robert E. W. Hancock, Octávio L. Franco, Ludovico Migliolo




Scientific Reports


Due to the growing concern about antibiotic-resistant microbial infections, increasing support has been given to new drug discovery programs. A promising alternative to counter bacterial infections includes the antimicrobial peptides (AMPs), which have emerged as model molecules for rational design strategies. Here we focused on the study of Pa-MAP 1.9, a rationally designed AMP derived from the polar fishPleuronectes americanus. Pa-MAP 1.9 was active against Gram-negative planktonic bacteria and biofilms, without being cytotoxic to mammalian cells. By using AFM, leakage assays, CD spectroscopy and in silicotools, we found that Pa-MAP 1.9 may be acting both on intracellular targets and on the bacterial surface, also being more efficient at interacting with anionic LUVs mimicking Gram-negative bacterial surface, where this peptide adopts α-helical conformations, than cholesterol-enriched LUVs mimicking mammalian cells. Thus, as bacteria present varied physiological features that favor antibiotic-resistance, Pa-MAP 1.9 could be a promising candidate in the development of tools against infections caused by pathogenic bacteria.




Circular dichroism, Secondary structure, Vesicle interactions, Pharmaceutical, Biochemistry