Table 1.

Summary of features and experimental observations for selected multicargo T3SC

Multicargo chaperone	pI/103 Mw	Known binding interaction(s) with secreted substratesa	Mutant virulence defect	Interaction with conserved T3SS component	Relevant references
InvB	4.5/14.9	SspA(SipA), SopE/E2, SopA	Yes		6, 19, 20, 43
Spa15	4.3/15.2	IpaA, IpgB1, IpgB2, OspB, OspC1, OspC2, OspC3, OspD1, OspD2	NDb		60, 61, 67
CesT	4.4/17.7	Tir, Map, EspF, EspG, EspH, EspZ, NleA, NleG, NleH, NleH2	Yes	EscN	1, 16, 23, 73
HpaB (162 aa)	4.3/18.5	AvrBs1, AvrBs3, XopF1	Yes	HrcN, HrcU, HrcV	3, 7, 8, 46
Mcsc	4.6/18.8	Ct618, Cap1, Ct225	ND	CdsQ	68
SrcA	4.6/16.1	SseL	Yes	SsaN	11

^aListed by direct interactions in experimental binding assays. Additional roles in effector secretion without demonstrated binding have been observed in some cases.

^bND, not determined.