TABLE 1.

Yersinia type III machinery components and their role in YopQ secretion

Type III proteinYsc solubilitya (%)YopQ secretion by Δ(ysc, yopD) mutantb (% of control)
YscD070
YscL1000
YscN500
YscQ10020
YscR00
YscS00
YscTNT0
YscU00
YscV00
ControlNA100
  • a Yersiniae were lysed by French press, and crude extracts were centrifuged (100,000 × g). Supernatant and sediment were separated and analyzed by immunoblotting with specific antisera. The amount of immuno reactive Ysc in the supernatant is shown. NT, not tested; NA, not applicable.

  • b YopQ secretion in low-calcium-induced Yersinia cultures was measured by immunoblotting. Y. enterocolitica VTL2 (ysc wild type) Δ(yopD) secreted 100% YopQ, whereas Δ(ysc, yopD) mutants displayed the secretion defects recorded.