Table 1.

Bacterial toxins and effector proteins that modulate the Unfolded Protein Response (UPR).

Bacterium	Toxin or Effector	Effect	Mode of Action	Reference
Brucella	VceC	Induces the UPR	Binds BiP	[31]
	TcpB (BtpA/Btp1]	Induces the UPR	Restructures ER tubules	[32]
	BspC, BspG, BspH, BspI, BspK	Induces the UPR	Unknown	[33]
Legionella	Lgt1, Lgt2, Lgt3	Inhibits XBP1 splicing	Inhibits translation elongation	[34,35]
Mycobacteria	ESAT-6, Heparin-Binding Haemagglutinin (HBHA)	Induces the UPR	Increases intracellular Ca2+ and Reactive Oxygen Species (ROS)	[36,37]
	Rv027	Induces the UPR	Increases intracellular Ca2+ and ROS	[38]
	Mpt64	Inhibits CHOP expression	Unknown, binds PIPs on ER membrane	[39]
Chlamydia	CT288, Tarp	Activates Ire1	Drives Ire1 oligomerisation	[40]
Salmonella	SlrP	Induces the UPR	Binds ERdj3, BiP cochaperone	[41,42]
Listeria	Listeriolysin O (LLO)	Induces the UPR	Increases intracellular Ca2+	[43]
Helicobacter	VacA	Activates Perk	Unknown	[44]
Vibrio cholerae	Cholera toxin (CT)	Induces the UPR	Binds BiP and ERdj3	[45,46]
E. coli	Subtilase cytotoxin	Induces the UPR	Cleaves BiP	[47,48,49]
	Shiga-like toxins (SLT)	Induces the UPR	Binds BiP and ERdj3	[50,51,52]