TABLE 1

Bacterial strains and plasmids

Strain or plasmidDescriptionReference or source
Strains
 Salmonella enterica serovar Cerro 87Strain contains the dndBCDE gene cluster with modification site at GAAC/GTTC60
 Escherichia coli DH10BF ΔmcrA (mrr-hsdRMS-mcrBC), cloning vectorInvitrogen
 Escherichia coli BL21(DE3)E. coli B strain with DE3, a λ prophage carrying the T7 RNA polymerase gene; host strain for protein hetero-expressionStratagene
Plasmids
    pET-28a (+)pBR322 origin, expression vector, KanrNovagen
    pET-15bpBR322 origin, expression vector, AmprNovagen
    pDndBCDEHDerived from pET-28a, with DNA region coding DndBCDE inserted at NcoI-XhoI sites, enables the host DNA phosphorothioation, Kanr52
    pDndBCDHDerived from pDndBCDEH, with in-frame deletion in dndE, Kanr52
    pDndBCEHDerived from pDndBCDEH, with in-frame deletion in dndD, Kanr52
    pDndBDEHDerived from pDndBCDEH, with in-frame deletion in dndC, Kanr52
    pDndBCHDerived from pET-28a, with DNA region coding DndBC, Kanr52
    pIscSDerived from pET-15b, with iscS gene and N-terminal His tag, AmprThis lab
    pDnd-DndC-C39ApDndBCDEH derivative, site mutant with C39A on DndC, KanrThis study
    pDnd-DndC-C146ApDndBCDEH derivative, site mutant with C146A on DndC, KanrThis study
    pDnd-DndC-C262ApDndBCDEH derivative, site mutant with C262A on DndC, KanrThis study
    pDnd-DndC-C273ApDndBCDEH derivative, site mutant with C273A on DndC, KanrThis study
    pDnd-DndC-C280ApDndBCDEH derivative, site mutant with C280A on DndC, KanrThis study
    pDnd-DndC-C283ApDndBCDEH derivative, site mutant with C283A on DndC, KanrThis study