RAB33B and legionellosis: The Sdc and Sde-dependent ubiquitination/PR-ubiquitination of host targets was not limited to Rab1 as several other previously reported Sde substrates, Rab33B 26, the autophagosomal SNARE protein Stx17 44, and an ER membrane protein, LULL1 45 showed a similar Sdc and Sde-dependent ubiquitination during Legionella infection (Extended data Fig. 1a–c).