Journal
MOLECULAR MICROBIOLOGY
Volume 87, Issue 5, Pages 1013-1028Publisher
WILEY
DOI: 10.1111/mmi.12147
Keywords
-
Categories
Funding
- Deutsche Forschungsgemeinschaft [MO970/3]
- Hartmut Hoffman-Berling International Graduate School of Molecular and Cellular Biology (HBIGS)
Ask authors/readers for more resources
The multicomponent type VI secretion system (T6SS) mediates the transport of effector proteins by puncturing target membranes. T6SSs are suggested to form a contractile nanomachine, functioning similar to the cell-puncturing device of tailed bacteriophages. The T6SS members VipA/VipB form tubular complexes and are predicted to function in analogy to viral tail sheath proteins by providing the energy for secretion via contraction. The ATPase ClpV disassembles VipA/VipB tubules in vitro, but the physiological relevance of tubule disintegration remained unclear. Here, we show that VipA/VipB tubules localize near-perpendicular to the inner membrane of Vibrio cholerae cells and exhibit repetitive cycles of elongation, contraction and disassembly. VipA/VipB tubules are decorated by ClpV in vivo and become static in clpV cells, indicating that ClpV is required for tubule removal. VipA/VipB tubules mislocalize in clpV cells and exhibit a reduced frequency of tubule elongation, indicating that ClpV also suppresses the spontaneous formation of contracted, non-productive VipA/VipB tubules. ClpV activity is restricted to the contracted state of VipA/VipB, allowing formation of functional elongated tubules at a T6SS assembly. Targeting of an unrelated ATPase to VipA/VipB is sufficient to replace ClpV function in vivo, suggesting that ClpV activity is autonomously regulated by VipA/VipB conformation.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available