Protein sequence alignment of A. nidulans CreB and the putative T. reesei orthologue. Black box denotes identical amino acids. Grey box denotes similar amino acids. Solid underline denotes the ubiquitin hydrolayse domain, Asp54 to Tyr474. The position of insertion of the A. nidulans amdS region is indicated, between Tyr425 and His426. Arrows denote the active sites, His428 and Asp437 of the ubiquitin hydrolase domain .