title: Design of multifunctional peptides expressing both antimicrobial activity and shiga toxin neutralization activity.
abstract: 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.
authors.affiliation: Department of Molecular Design and Engineering, Graduate School of Engineering, Nagoya University, Chikusa, Nagoya 464-8603, Japan.
authors.forename: Yoshinao
authors.initials: Y
authors.lastname: Yamada
authors.forename: Yoshiko
authors.initials: Y
authors.lastname: Miura
authors.forename: Akio
authors.initials: A
authors.lastname: Sakaki
authors.forename: Tetsuhiko
authors.initials: T
authors.lastname: Yoshida
authors.forename: Kazukiyo
authors.initials: K
authors.lastname: Kobayashi
mesh_terms: D000595:Amino Acid Sequence; D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000494:pharmacology*; D015195:Drug Design; D006367:HeLa Cells; D006801:Humans; D008826:Microbial Sensitivity Tests; D010455:Peptides / Q000737:chemistry / Q000494:pharmacology*; D022621:Shiga Toxin / Q000037:antagonists & inhibitors*; D020349:Surface Plasmon Resonance
chemical_list: D000900:Anti-Bacterial Agents; D010455:Peptides; D022621:Shiga Toxin