. Author manuscript; available in PMC: 2010 Sep 1.

Published in final edited form as: Nat Rev Microbiol. 2009 Sep;7(9):654–665. doi: 10.1038/nrmicro2199

Table 1.

Characteristics of P. aeruginosa T3SS effector proteins.

Effector protein	Size (kDa)	Chaperone	Substrates	Cofactor for activation
ExoS	49	SpcS	GAP activity: Rho, Rac, and Cdc42 ADPRT activity: ezrin, radixin, moesin, vimentin, cyclophilin A, IgG₃, apolipoprotein A1, Ras, Rac1, Cdc42, Rabs 1, 3, 5, 7, 8, and 11, RalA, Rap1, Rap2	14-3-3 proteins
ExoT	53	SpcS	GAP activity: Rho, Rac, and Cdc42 ADPRT activity: Crk-I, Crk-II, phosphoglycerate kinase	14-3-3 proteins
ExoU	74	SpcU	phospholipids, lysophospholipids, neutral lipids	SOD1
ExoY	41	?	ATP	?

GAP: GTPase activating protein

ADPRT: adenosine diphosphate ribosyl transferase

Crk: CT10-regulator of kinase

SOD1: Cu²⁺, Zn²⁺-superoxide dismutase

?: unknown

Please see text for citations