Design of multifunctional peptides expressing both antimicrobial activity and shiga toxin neutralization activity

• Published in: Bioorganic & medicinal chemistry Vol. 14; no. 1; pp. 77 - 82
• Main Authors: YAMADA, Yoshinao, MIURA, Yoshiko, SAKAKI, Akio, YOSHIDA, Tetsuhiko, KOBAYASHI, Kazukiyo
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Science 2006
• Subjects: Amino Acid Sequence; Anti-Bacterial Agents - chemistry; Anti-Bacterial Agents - pharmacology; Antibacterial agents; Antibiotics. Antiinfectious agents. Antiparasitic agents; Bacteriology; Biological and medical sciences; Drug Design; Fundamental and applied biological sciences. Psychology; HeLa Cells; Humans; Medical sciences; Microbial Sensitivity Tests; Microbiology; Pathogenicity, virulence, toxins, bacteriocins, pyrogens, host-bacteria relations, miscellaneous strains; Peptides - chemistry; Peptides - pharmacology; Pharmacology. Drug treatments; Shiga Toxin - antagonists & inhibitors; Surface Plasmon Resonance; Oligopeptides; Peptides; Cyclic peptides; Toxicity; Escherichia coli; Cytotoxicity; Uterine cervix; Antibacterial; Structure activity relation; Gram positive bacteria; Bacteria; Micrococcales; Micrococcaceae; Drug design; Inhibition; Staphylococcus aureus; Shiga like toxin; Enterobacteriaceae; Gram negative bacteria; Human; Peptidomimetic compound; Shiga toxins; In vitro; Hela cell line; Cell line; Polypeptide; Antibacterial agent; Neutralization
• ISSN: 0968-0896; 1464-3391
• DOI: 10.1016/j.bmc.2005.07.052

We have designed novel short peptides expressing both antimicrobial and Shiga-toxin (Stx) neutralization activities by combining nuclear localization signal (NLS) peptides (RIRKKLR, PKKKRKV, and PRRRK) tandemly with globotriaoside (Gb3) mimic peptide (WHWTWL). These fusion peptides exhibited excellent antimicrobial activity against both gram-positive and gram-negative bacteria. A peptide WHWTWLRIRKKLR (Trp-His-Trp-Thr-Trp-Leu-Arg-Ile-Arg-Lys-Lys-Leu-Arg), especially, exhibited about 100 times higher activity than the original NLS peptide. SPR analysis demonstrated that the binding of this peptide to both Stxs was strong: K(d) = 6.6 x 10(-6) to Stx-1 and 6.8 x 10(-6) to Stx-2. The in vitro assay against Stx-1 using HeLa cells showed that this peptide increased the survival rate of HeLa cells against the infection of Stx-1. The peptide has been found to maintain high antimicrobial activity, Stx neutralization activity, and no cytotoxicity at its concentration of 7.8-31.3 microg/mL (4.2-16.7 microM). The present peptide design has a prospect of developing potent multifunctional drugs to destroy proteinaceous toxin-producing bacteria and to simultaneously neutralize the toxins released by bacteriolysis.