title: Identification of peptide inhibitors of Pseudomonas aeruginosa exotoxin A function using a yeast two-hybrid approach.
abstract: The yeast two-hybrid system was used to identify peptide inhibitors of exotoxin A of Pseudomonas aeruginosa with the goal of using these to design peptide-based drugs against the toxin. A random peptide library consisting of 10(7) peptides ranging in length from 16 to 63 residues was screened for peptides that interact with the C-domain of exotoxin A. From the 10(7) transformants screened, three unique peptides of 63, 61 and 25 amino acids in length were found to specifically interact with the enzyme domain. The genes encoding these peptides were cloned and expressed as fusion proteins with the maltose-binding protein. In vitro inhibition measurements indicated that two of the peptides were modest inhibitors of toxin enzyme activity. These peptides now provide the basis for the development of more potent inhibitors, which will serve as lead inhibitors for evolution of potent peptide-based therapeutics.
authors.affiliation: Department of Chemistry and Biochemistry, University of Guelph, Guelph, ON, Canada N1G 2W1.
authors.forename: Crista
authors.initials: C
authors.lastname: Thompson
authors.forename: A Rod
authors.initials: AR
authors.lastname: Merrill
authors.forename: Dev
authors.initials: D
authors.lastname: Mangroo
mesh_terms: D036002:ADP Ribose Transferases / Q000037:antagonists & inhibitors*; D000595:Amino Acid Sequence; D001427:Bacterial Toxins / Q000037:antagonists & inhibitors*; D001483:Base Sequence; D005098:Exotoxins / Q000037:antagonists & inhibitors*; D008969:Molecular Sequence Data; D019151:Peptide Library; D010455:Peptides / Q000235:genetics / Q000302:isolation & purification; D011550:Pseudomonas aeruginosa / Q000235:genetics* / Q000254:growth & development; D020798:Two-Hybrid System Techniques; D037521:Virulence Factors / Q000037:antagonists & inhibitors*; D015003:Yeasts; D000097668:Pseudomonas aeruginosa Exotoxin A
chemical_list: D036002:ADP Ribose Transferases; D001427:Bacterial Toxins; D005098:Exotoxins; D019151:Peptide Library; D010455:Peptides; D037521:Virulence Factors; D000097668:Pseudomonas aeruginosa Exotoxin A