The Two Deubiquitinating Enzymes from Chlamydia trachomatis have Distinct Ubiquitin Recognition Properties

Chlamydia trachomatis is the cause of several diseases such as sexually transmitted urogenital disease and ocular trachoma. The pathogen contains a small genome yet, upon infection, expresses two enzymes with deubiquitinating activity, termed ChlaDUB1 ChlaDUB2, presumed to have redundant deubiquitinase (DUB) function because similarity primary structure their catalytic domain. Previous studies led structural characterization enzymatic properties ChlaDUB1; however, ChlaDUB2 has yet be investigated thoroughly. In this study, we compared them those ChlaDUB1. This revealed distinct difference in hydrolytic activity regard di- polyubiquitin chains while showing similar ability cleave monoubiquitin-based substrate, ubiquitin aminomethylcoumarin (Ub-AMC). was unable diubiquitin substrate efficiently, whereas could rapidly hydrolyze like prototypical prokaryotic DUB, SdeA. With polyubiquitinated green fluorescent protein (GFP-Ubn), efficiently disassembled into monoubiquitin product, deubiquitination depletion did not produce appreciable levels product. We report structures construct its complex propargyl amide. These differences residues involved recognition between DUBs. On basis structures, conclude that distal binding equivalent DUBs, consistent Ub-AMC result. Therefore, longer ubiquitinated substrates may due differential these involving additional sites.