title: Novel internally quenched substrate of the trypsin-like subunit of 20S eukaryotic proteasome.
abstract: This article describes the synthesis, using combinatorial chemistry, of internally quenched substrates of the trypsin-like subunit of human 20S proteasome. Such substrates were optimized in both the nonprime and prime regions of the peptide chain. Two were selected as the most susceptible for proteasomal proteolysis with excellent kinetic parameters: (i) ABZ-Val-Val-Ser-Arg-Ser-Leu-Gly-Tyr(3-NO2)-NH2 (kcat/KM = 934,000 M(-1) s(-1)) and (ii) ABZ-Val-Val-Ser-GNF-Ala-Met-Gly-Tyr(3-NO2)-NH2 (kcat/KM = 1,980,000 M(-1) s(-1)). Both compounds were efficiently hydrolyzed by the 20S proteasome at picomolar concentrations, demonstrating significant selectivity over other proteasome entities.
authors: Faculty of Chemistry, University of Gdansk, 80-308 Gdansk, Poland.
authors: Natalia
authors: N
authors: Gruba
authors: Faculty of Chemistry, University of Gdansk, 80-308 Gdansk, Poland.
authors: Magdalena
authors: M
authors: Wysocka
authors: Faculty of Chemistry, University of Gdansk, 80-308 Gdansk, Poland.
authors: Magdalena
authors: M
authors: Brzezińska
authors: Faculty of Chemistry, University of Gdansk, 80-308 Gdansk, Poland.
authors: Dawid
authors: D
authors: Debowski
authors: Faculty of Chemistry, University of Gdansk, 80-308 Gdansk, Poland.
authors: Krzysztof
authors: K
authors: Rolka
authors: Faculty of Science, Utrecht University, 3512 JE Utrecht, The Netherlands.
authors: Nathaniel I
authors: NI
authors: Martin
authors: Faculty of Chemistry, University of Gdansk, 80-308 Gdansk, Poland. Electronic address: adam.lesner@ug.edu.pl.
authors: Adam
authors: A
authors: Lesner
mesh_terms: D020650:Combinatorial Chemistry Techniques; D006801:Humans; D057230:Limit of Detection; D010455:Peptides / Q000037:antagonists & inhibitors / Q000138:chemical synthesis / Q000737:chemistry* / Q000378:metabolism; D046988:Proteasome Endopeptidase Complex / Q000737:chemistry* / Q000378:metabolism; D059748:Proteolysis; D014357:Trypsin / Q000737:chemistry* / Q000378:metabolism
chemical_list: D010455:Peptides; D014357:Trypsin; D046988:Proteasome Endopeptidase Complex
keywords: 20S Eukaryotic proteasome; Fluorescence; Internally quenched peptides