Figure 4

Nedd8-AMC processing ability of some of the mutant strains. The Δuch1Δuch2Δnep1Δnep2 strain shows reduced levels of activity (66% of wild type) while the 5 gene deletion strain, Δuch1Δuch2Δnep1Δnep2Δcsn5 shows even less activity (45% of wild type). However there is still processing activity unaccounted for by these 5 enzymes. This activity can be further reduced upon incubation with ubiquitin-aldehyde, but not o-phenanthroline. This suggests that other ubiquitin proteases could account for the remaining activity, but that these proteases are not metalloproteases. (n = 5, S.E.M. shown as error bars).