Host-Pathogen Interactions

Use It, Then Lose It

Sci. Signal.  26 Jul 2011:
Vol. 4, Issue 183, pp. ec208
DOI: 10.1126/scisignal.4183ec208

Pathogenic bacteria encode effector proteins that AMPylate (covalently attach adenosine monophosphate to) target host factors, such as Rho or Rab guanosine triphosphatases. AMPylation interferes with downstream signaling events, thereby promoting microbial infection. How AMPylation of host factors is regulated during infection and whether it can be reversed within cells is unclear. Neunuebel et al. have now discovered that Legionella pneumophila, in addition to secreting an AMPylation enzyme, also translocates a de-AMPylase, SidD, into host cells. SidD thus represents the missing link between the processes of early Rab1 accumulation and subsequent Rab1 removal from Legionella-containing vacuoles during infection.

M. R. Neunuebel, Y. Chen, A. H. Gaspar, P. S. Backlund Jr., A. Yergey, M. P. Machner, De-AMPylation of the small GTPase Rab1 by the pathogen Legionella pneumophila. Science 333, 453–456 (2011). [Abstract] [Full Text]