Bioengineering and functional characterization of arenicin shortened analogs with enhanced antibacterial activity and cell selectivity.
New bioengineering approaches are required for development of more active and less toxic antimicrobial peptides. In this study we used β-hairpin antimicrobial peptide arenicin-1 as a template for design of more potent antimicrobials. In particular, six shortened 17-residue analogs were obtained by recombinant expression in Escherichia coli. Besides, we have introduced the second disulfide bridge by analogy with the structure of tachyplesins. As a result, a number of analogs with enhanced activity and cell selectivity were developed. In comparison with arenicin-1, which acts on cell membranes with low selectivity, the most potent and promising its analog termed ALP1 possessed two-fold higher antibacterial activity and did not affect viability of mammalian cells at concentration up to 50 μM. The therapeutic index of ALP1 against both Gram-positive and Gram-negative bacteria was significantly increased compared with that of arenicin-1 while the mechanism of action remained the same. Like arenicin-1, the analog rapidly disrupt membranes of both stationary and exponential phase bacterial cells and effectively kills multidrug-resistant Gram-negative bacteria. Furthermore, ALP1 was shown to bind DNA in vitro at a ratio of 1:1 (w/w). The circular dichroism spectra demonstrated that secondary structures of the shortened analogs were similar to that of arenicin-1 in water solution, but significantly differed in membrane-mimicking environments. This work shows that a strand length is one of the key parameters affecting cell selectivity of β-hairpin antimicrobial peptides.
['Panteleev|Pavel V|PV|', 'Bolosov|Ilia A|IA|', 'Ovchinnikova|Tatiana V|TV|']
D000595:Amino Acid Sequence D000900:Anti-Bacterial Agents D023181:Antimicrobial Cationic Peptides D004912:Erythrocytes D004926:Escherichia coli D015801:Helminth Proteins D006461:Hemolysis D006801:Humans D008826:Microbial Sensitivity Tests D008969:Molecular Sequence Data D010539:Permeability D010957:Plasmids D011485:Protein Binding D015202:Protein Engineering D011550:Pseudomonas aeruginosa D013211:Staphylococcus aureus
bioengineering arenicin antimicrobial peptide β-hairpin therapeutic index heterological expression