Table 1.

Properties of plasmid-encoded TA loci

LocusaOrganismToxin (no. of aa)TargetAntitoxin (no. of aa)ProteasePSKReference(s)
ccd of F E. coli CcdB (101)DNA gyraseCcdA (72)LonYes 57, 58, 67,95, 96
pem/parD of R100/R1 E. coli PemK/Kid (110)DnaB?PemI/Kis (84)LonYes 10, 77, 91,92
phd-doc of P1 E. coli Doc (126)UnknownPhd (73)ClpXPYes 46,47
parDE of RK2BHRb ParE (103)UnknownParD (83)UnknownYes 72
relBE/pasABC T. ferrooxidans PasB (90)UnknownPasA (74)LonYes 82, 83, 84
stb of pMYSH6000 S. flexneri Orf2 (133)UnknownOrf1 (75)UnknownNDc 69
hig of Rts1BHRHigB (92)UnknownHigA (104)UnknownYes 90
ɛ/ζ of pSM19035 BHRζ (287)Unknownɛ (90)UnknownYes 13
relBE of P307 E. coli RelE (95)TranslationRelB (83)LonYes 30
relBE/stbDE of R485 M. morganii RelE/StbE (93)UnknownRelB/StbD (83)UnknownYes 32
relBE of pJK21 A. europaeus RelE (93)UnknownRelB (87)UnknownNDThis work
relBE of pRJF2 B. fibrisolvens RelE (93)UnknownRelB (83)UnknownNDThis work
relBE of pB171 E. coli RelE (95)UnknownRelB (83)UnknownNDThis work
relBE of p11184 P. shigelloides RelE (94)UnknownRelB (80)UnknownNDThis work
  • a Plasmid R485 is from M. morganii, pMYSH6000 is from Shigella flexneri, pJK21 from Acetobacter europaeus, pasABC is from theT. ferrooxidans plasmid pTF-CF2, ω-ɛ-ζ of pSM19035 is from S. pyogenes, and plasmid pRJF2 is from B. fibrisolvens; all other loci are from E. coli plasmids or broad-host-range plasmids (RK2/RP4, Rts1 and pSM19035). Broad-host-range plasmid RK2/RP4 is from gram-negative bacteria, pSM19035 is from gram-positive bacteria.

  • b BHR, broad-host-range plasmid.

  • c ND, not determined.