Ubiquitin-dependent processes control much of cellular physiology. We show that expression of a highly active. Epstein-Barr virus-derived deubiquitylating enzyme (EBV-DUB) blocks proteasomal degradation of cytosolic and ER-derived proteins by preemptive removal of ubiquitin from proteasome substrates. a treatment less toxic than the use of proteasome inhibitors. https://jalyttlers.shop/product-category/o-rings/