The DUB blade goes snicker-snack： Novel ubiquitin cleavage by a Legionella effector protein

Recently, a Legionellapneumophila effector protein was shown to have an unprecedented ATP-independent ubiquitin ligase activity that couples phosphoribosylated ubiquitin （PR- Ub） to serine residues of host pro- teins. A new study published in Cell Research by Qiu et al.reveals that anothar Legionella effector protein, SidJ, catalyzes deubiquitination of PR-Ub by cleavage of the substrate- linked phosphodiester bond.