Table 3.

Overview of restriction–modification (RM) systems.

Name of locus	Toxin/antitoxin	Organism	References
ecoRI	EcoRI/M.EcoRI	E. coli	Hedgpeth et al. (1972); Kulakauskas et al. (1995)
ecoRII	EcoRII/M.EcoRII	E. coli	Som et al. (1987); Som and Friedman (1993); Karyagina et al. (1997); Takahashi et al. (2002); Ohno et al. (2008)
ecoRV	EcoRV/M.EcoRV	E. coli	Nakayama and Kobayashi (1998)
ssoII	SsoII/M.SsoII	Shigella sonnei	Karyagina et al. (1997); Kobayashi (2004)
paeR71	PaeR71/M.PaeR71	P. aeroginosa	Wilson and Murray (1991); Kusano et al. (1995); Kobayashi (2004)
pvuII	PvuII/M.PvuII	P. vulgaris	Tao et al. (1991); Cheng et al. (1994); Calvin‐Koons and Blumenthal (1995); Gong et al. (1997)
bsp6I	Bsp6I/M.Bsp6I	Bacillus sp. RFL6I	Kulakauskas et al. (1995); Lubys and Janulaitis (1995)
haeII	HaeII/M.HaeII	Haemophilus aegyptius	Tu et al. (1976)
dcm–vsr	None/Dcm	E. coli	Lieb (1991); Palmer and Marinus (1994); Takahashi et al. (2002); Bunting et al. (2003)

Table displays the host origin, involved toxin/antitoxin as described in literature.