Table 6.

Yop effectors

ProteinSize (kDa)Action on the cellEnzymatic activityRelevant similaritiesLocalization in the target cellSufficient signals fora:Reference(s)
Secretion (aa or codons)Translocation (aa)
YopE22.9Disruption of the cytoskeleton; rounding up of cells; detachment from extracellular matrixCytotoxicityExoS (P. aeruginosa); SptP/StpA (Salmonella)Perinuclear region1150 10, 14,184, 282, 283, 300, 321, 378
YopH51.0Disruption of peripheral focal complexesPTPaseEukaryotic phosphatases; SptP/StpA (Salmonella)Cytoplasm1771 14, 31,32, 46, 132, 184, 258, 321, 340
YopM41.6UnknownUnknowny4fR (Rhizobium); IpaH (Shigella); numerous proteoglycans; GP1bαUnknown40100 41, 104, 148, 207,208
YpkA/YopO81.7Rounding up of cellsSer/Thr kinaseSer/Thr kinases; COT oncogeneInner surface of plasma membrane7777 74, 110, 137, 324
YopP/YopJ32.5Apoptosis of macrophages; inhibition of TNF-α releaseCytotoxicityAvRxv (X. campestris); AvrA (Salmonella)Cytoplasm9999 41,144, 232, 237, 251, 324
YopT35.5Disruption of actin filamentsCytotoxicityp76 (H. somnus)Unknown124124 170
  • a aa, amino acids.