Table 2.

Type I R-M systems identified in members of the family Enterobacteriaceae

R-M familyEnzymeTarget sequenceReference(s)
IA EcoKIa AAC(N6)GTGC 79
EcoBIb TGA(N8)TGCT 147
EcoDITTA(N7)GTCY 125
StyLTIIIc GAG(N6)RTAYG 126
StySPIAAC(N6)GTRC 126
EcoR5INDd 11
EcoR10Ie ND 11
EcoR23IND 11
IB EcoAIGAG(N7)GTCA 91,168
EcoEIGAG(N7)ATGC 33
CfrAIGCA(N8)GTGG 80
StySKICGAT(N7)GTTA 179
StySTIND 10
EcoR17IND 11
EcoR42IND 11
IC EcoR124IGAA(N6)RTCG 142
EcoDXXITCA(N7)RTTC 64
EcoprrICCA(N7)RTGC 183
ID StySBLICGA(N6)TACC 180; Titheradge and Murray, unpublished
EcoR9IND 11
KpnAIND 101
  • a Strains ECOR12 and -24 have type IA systems with the same specificity.

  • b Strains ECOR14, 42 and 70 have type IA systems with the same specificity.

  • c Referred to as StySBI in the early literature.

  • d ND, not done.

  • e Strain ECOR25 has a type IA system with the same specificity.