Effect of inhibition of proteasome-mediated proteolysis on ligninolytic activities of white-rot fungi

Nam Seok Cho, Magdalena Staszczak, Jerzy Rogalski, Hee Yeon Cho, Shoji Ohga

Research output: Contribution to journalArticlepeer-review


It has recently been established that most short- and long-lived cellular proteins (80-90%) are degraded by a highly selective non-lysosomal pathway that requires ATP and a large (-2.5 MDa) multisubunit, multicatalytic proteinase complex known as the 26S proteasome. It degrades many important proteins involved in signaling pathway, in cell cycle control, and in general metabolism, including transcription factors and key metabolic enzymes. Here, we demonstrated all distinct proteasome activities: chymotrypsinlike, trypsin-like, and caspase-like (peptidylglutamyl-peptide hydrolyzing) in mycelial extracts of the white-rot fungi Trametes versicolor and Phlebia radiata by monitoring cleavage of three different fluorogenic peptide substrates: Suc-LLVY-MCA, Z-GGR-MCA, Z-LLE-βSNA, respectively. We also found that this cleavage was ATP-dependent. Reagents that inhibit proteasome-mediated protein degradation in intact cells have recently become available, including substrate-related peptide aldehydes. These inhibitors are useful tools to demonstrate that a process exhibits proteasome-dependent biochemical regulation. In the present study, we report that in vivo Cbz-LLLal treatment strongly inhibited all tested proteasome activities and affected ligninolytic activities in nutrient deprived cultures of both fungi.

Original languageEnglish
Pages (from-to)399-404
Number of pages6
JournalJournal of the Faculty of Agriculture, Kyushu University
Issue number2
Publication statusPublished - Oct 2008

All Science Journal Classification (ASJC) codes

  • Agronomy and Crop Science
  • Biotechnology


Dive into the research topics of 'Effect of inhibition of proteasome-mediated proteolysis on ligninolytic activities of white-rot fungi'. Together they form a unique fingerprint.

Cite this