title: New method of peptide cleavage based on Edman degradation.
abstract: A straightforward cleavage method for N- acylated peptides based on the phenylthiohydantoin (PTH) formation is presented. The procedure could be applied to acid-stable resins, such as TentaGel HL-NH[Formula: see text]. We designed a cleavable linker that consists of a lysine residue with the [Formula: see text]-amino group blocked by Boc, whereas the [Formula: see text]-amino group is used for peptide synthesis. After the peptide assembly is completed, the protecting groups in peptide side chains are removed using trifluoroacetic acid, thus liberating also the [Formula: see text]-amino group of the lysine in the linker. Then the reaction with phenyl isothiocyanate followed by acidolysis causes an efficient peptide release from the resin as a stable PTH derivative. Furthermore, the application of a fixed charge tag in the form of 2-(4-aza-1-azoniabicyclo[2.2.2]octylammonium)acetyl group increases ionization efficiency and reduces the detection limit, allowing ESI-MS/MS sequencing of peptides in the subfemtomolar range. The proposed strategy is compatible with standard conditions during one-bead-one-compound peptide library synthesis. The applicability of the developed strategy in combinatorial chemistry was confirmed using a small training library of [Formula: see text]-chymotrypsin substrates.
authors.affiliation: Faculty of Chemistry, University of Wrocław, ul. F. Joliot-Curie 14, 50-383 , Wrocław, Poland.
authors.forename: Remigiusz
authors.initials: R
authors.lastname: Bąchor
authors.forename: Alicja
authors.initials: A
authors.lastname: Kluczyk
authors.forename: Piotr
authors.initials: P
authors.lastname: Stefanowicz
authors.forename: Zbigniew
authors.initials: Z
authors.lastname: Szewczuk
mesh_terms: D000595:Amino Acid Sequence; D020650:Combinatorial Chemistry Techniques; D019151:Peptide Library; D010455:Peptides / Q000737:chemistry*; D010669:Phenylthiohydantoin / Q000737:chemistry*; D020539:Sequence Analysis, Protein / Q000379:methods*; D053719:Tandem Mass Spectrometry
chemical_list: D019151:Peptide Library; D010455:Peptides; D010669:Phenylthiohydantoin