title: Synthetic peptides as artificial receptors towards proteins from genetically modified organisms.
abstract: The aim of this work was the preparation of peptide ligands with good affinity and selectivity towards proteins from genetically modified organisms, namely neomycin phosphotransferase II (Npt II) and the endotoxin Cry1A. A 12 x 12 combinatorial solid phase synthesis in aqueous medium was performed to prepare peptide libraries. From this library, two dipeptides with binding properties towards the chosen ligands (Pro-Lys for Npt II, K(eq) 7.59 x 10(4)M(-1); Trp-Gln for Cry 1A, K(eq) 4.35 x 10(4)M(-1)) were selected as scaffolds for the synthesis of new tetrapeptide libraries. The equilibrium constants of the newly selected tetrapeptides increased slightly respect to the dipeptides (Pro-Lys-His-Phe for Npt II, K(eq) 7.88 x 10(4)M(-1); Trp-Gln-Ala-Phe for Cry 1A, K(eq) 5.65 x 10(4)M(-1)), but selectivity towards other proteins (wheat gliadins, bovine gamma-globulins, bovine serum albumin and chicken ovalbumin) became higher. It was demonstrated that selected tetrapeptides recognised well the ligands also in presence of very complex mixtures of potentially interfering proteins, such as whole cell lysates. This approach can be considered as a general method to obtain tailor-made reagents with antibody-like binding properties towards biomacromolecules.
authors.affiliation: Department of Analytical Chemistry, Laboratory of Bioanalytical Chemistry, University of Torino, Torino, Italy.
authors.forename: Cinzia
authors.initials: C
authors.lastname: Tozzi
authors.forename: Laura
authors.initials: L
authors.lastname: Anfossi
authors.forename: Claudio
authors.initials: C
authors.lastname: Baggiani
authors.forename: Cristina
authors.initials: C
authors.lastname: Giovannoli
authors.forename: Gianfranco
authors.initials: G
authors.lastname: Giraudi
mesh_terms: D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins / Q000737:chemistry*; D020650:Combinatorial Chemistry Techniques / Q000379:methods*; D004731:Endotoxins / Q000737:chemistry*; D006460:Hemolysin Proteins / Q000737:chemistry*; D019868:Kanamycin Kinase / Q000737:chemistry*; D009842:Oligopeptides / Q000737:chemistry*; D030781:Organisms, Genetically Modified / Q000378:metabolism*; D019151:Peptide Library
chemical_list: D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins; D004731:Endotoxins; D006460:Hemolysin Proteins; D009842:Oligopeptides; D019151:Peptide Library; C030956:insecticidal crystal protein, Bacillus Thuringiensis; D019868:Kanamycin Kinase