title: Peptide splicing in a double-sequence analogue of trypsin inhibitor SFTI-1 substituted in the P₁ positions by peptoid monomers.
abstract: Recently, we described a process of trypsin-assisted peptide splicing of analogs of trypsin inhibitor SFTI-1, that seems to be very similar to proteasome-catalyzed peptide splicing. Here, we show, for the first time, that a peptide-peptoid hybrid (peptomer) can also be spliced by trypsin. Incubation of a double sequence SFTI-1 analog, containing two peptoid monomers, with equimolar amount of trypsin leads to formation of monocyclic peptomer as the main product. We proved that the peptide bond formed by a peptoid monomer is not only digested by trypsin but also participates in the enzyme-assisted splicing process.
authors.affiliation: Department of Chemistry, University of Gdansk, Wita Stwosza 63, 80-952, Gdansk, Poland.
authors.forename: Natalia
authors.initials: N
authors.lastname: Karna
authors.affiliation: Department of Chemistry, University of Gdansk, Wita Stwosza 63, 80-952, Gdansk, Poland.
authors.forename: Dawid
authors.initials: D
authors.lastname: Dębowski
authors.affiliation: Department of Chemistry, University of Gdansk, Wita Stwosza 63, 80-952, Gdansk, Poland.
authors.forename: Anna
authors.initials: A
authors.lastname: Łęgowska
authors.affiliation: Department of Chemistry, University of Wroclaw, F. Joliot-Curie 14, 50-383, Wroclaw, Poland.
authors.forename: Remigiusz
authors.initials: R
authors.lastname: Bąchor
authors.affiliation: Department of Chemistry, University of Wroclaw, F. Joliot-Curie 14, 50-383, Wroclaw, Poland.
authors.forename: Zbigniew
authors.initials: Z
authors.lastname: Szewczuk
authors.affiliation: Department of Chemistry, University of Gdansk, Wita Stwosza 63, 80-952, Gdansk, Poland.
authors.forename: Krzysztof
authors.initials: K
authors.lastname: Rolka
mesh_terms: D000818:Animals; D002417:Cattle; D010456:Peptides, Cyclic / Q000737:chemistry*; D019154:Protein Splicing; D014357:Trypsin / Q000737:chemistry*; D014361:Trypsin Inhibitors / Q000737:chemistry*
chemical_list: D010456:Peptides, Cyclic; C448501:SFTI-1 peptide, sunflower; D014361:Trypsin Inhibitors; D014357:Trypsin
keywords: SFTI-1 inhibitor; mass spectrometry; peptide splicing; peptomer