AnkB F-Box

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AnkB F-Box is a protein excreted by Legionella pneumophila which contains a domain F-box.

F-box proteins are involved in the ubiquitination of proteins targeted for degradation by the proteasome. AnkB F-box is a protein that assembles host cell polyubiquitinated proteins on the cytoplasmatic side of Legionella containing vacuole (LCV). [1]

This effector is required for intracellular proliferation within human and amoeba cells and for intrapulmonary Legionella proliferation in mice. The presence of the F-box domain is an example of molecular mimicry of eukaryotic F-box by which Legionella exploits the proteasomal degradation capacity of the host cell for its own sake. [2]

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References

  1. Christopher T. D. Price, Tasneem Al-Quadan, Marina Santic, Ilan Rosenshine, Yousef Abu Kwaik. Host Proteasomal Degradation Generates Amino Acids Essential for Intracellular Bacterial Growth. SCIENCE VOL 334 16 DECEMBER 2011
  2. Price C. T., Al-Khodor S., Al-Quadan T., Santic M., Habyarimana F., Kalia A., Kwaik Y. A. (2009). Molecular mimicry by an F-Box Effector of Legionella pneumophila hijacks a conserved polyubiquitination machinery within macrophages and protozoa. PLoS Pathog. 5, e1000704. doi: 10.1371/journal.ppat.1000704.