The Rab1 in host cells modulates Brucella intracellular survival and binds to Brucella DnaK protein.

The intracellular pathogen Brucella abortus (B. abortus) survives and replicates inside host cells within the Brucella-containing vacuole, in which membrane contains a small GTPase Rab1. Here, we reported that Rab1 mediates B. abortus intracellular growth. Furthermore, B. abortus DnaK was identified to interact with Rab1 using GST pull-down and mass spectrometry analysis. This interaction was confirmed by co-immunoprecipitation and immunofluorescence. Through DnaK-CyaA fusion protein translocation assay and immunofluorescence confocal microscopy, the B. abortus DnaK was proved to be a virB-dependent translocated substrate.