Abstract:
Proteasomes are cellular proteases involved in the degradation of numerous cellular proteins. The 20S proteasome is a cylindrical 28-mer protein complex composed of two outer heptameric α-rings forming the entrance for the protein substrate and two inner heptameric β-rings carrying the catalytic sites. Numerous in vitro studies have provided evidence that the 20S proteasome may degrade peptides of various lengths and even unfolded full-length polypeptide chains. However, a direct demonstration that the 20S proteasome may also cleave surface-attached immobilized peptides is lacking so far. To this end, we used a model system by coupling peptides from different source proteins covalently to the surface of glass beads and applied nanoLC/MS analysis to monitor the generation of proteolytic fragments in the presence of the 20S proteasome. Detectable amounts of cleavage products occurred within a few minutes indicating a much higher cleavage rate than observed with the same substrates in solution. Our finding lends support to the idea that proteasomes may directly degrade segments of membrane-bound proteins protruding into the aqueous phase. Copyright © 2013 European Peptide Society and John Wiley & Sons, Ltd.
Projects: No Projects
J. Pept. Sci.
J. Pept. Sci. 19(9): 588-97
28th Jul 2013
Marc Hovestädt, Ulrike Kuckelkorn, Agathe Niewienda, Christin Keller, Andrean Goede, Bernhard Ay, Stefan Günther, Katharina Janek, Rudolf Volkmer, Hermann-Georg Holzhütter
Authors
Attributions
None
Scales
Not Specified
- Created: 9th Sep 2013 at 15:19
- Last updated: 24th Oct 2013 at 16:14
Related items
