Table 4.

CobB or an uncharacterized Pdu protein is required forprpBCDE transcription in response to propionate or 1,2-PDL

StrainbRelevant genotypeMean β-galactosidase activity ± SD (U/A650 unit) in cells grown in minimal mediuma supplemented with:Growth on PrpcGrowth on Prp, 1,2-PDLd
No additions1,2-PDL
JE4334 cobB +DUP1033[proA-pyrC]prpC114::MudJ663 ± 51770 ± 20YesYes
JE4265DEL1184cobBDUP1033[proA-pyrC]prpC114::MudJ28 ± 7750 ± 37NoYes
JE4359DEL1184cobBDUP1033[proA-pyrC]prpC114::MudJpdu-8::MudA21 ± 317 ± 2NoNo
JE4402JE4265/pCOBB5cobB + 692 ± 50NDe YesYes
  • a NCE medium (7) containing glycerol (22 mM) and propionate (30 mM).

  • b All strains were derivatives of strain TR6583 (metE205 ara-9).

  • c NCE medium with 30 mM propionate (Prp) was the sole carbon and energy source.

  • d NCE medium with 30 mM propionate (Prp) and 12 mM 1,2-PDL. The medium did not contain cobalamin to prevent 1,2-PDL degradation.

  • e ND, not determined.