Propionyl coenzyme A is a common intermediate in the 1,2-propanediol and propionate catabolic pathways needed for expression of the prpBCDE operon during growth of Salmonella enterica on 1,2-propanediol

J Bacteriol. 2003 May;185(9):2802-10. doi: 10.1128/jb.185.9.2802-2810.2003.

Abstract

The studies reported here identify propionyl coenzyme A (propionyl-CoA) as the common intermediate in the 1,2-propanediol and propionate catabolic pathways of Salmonella enterica serovar Typhimurium LT2. Growth on 1,2-propanediol as a carbon and energy source led to the formation and excretion of propionate, whose activation to propionyl-CoA relied on the activities of the propionate kinase (PduW)/phosphotransacetylase (Pta) enzyme system and the CobB sirtuin-controlled acetyl-CoA and propionyl-CoA (Acs, PrpE) synthetases. The different affinities of these systems for propionate ensure sufficient synthesis of propionyl-CoA to support wild-type growth of S. enterica under low or high concentrations of propionate in the environment. These redundant systems of propionyl-CoA synthesis are needed because the prpE gene encoding the propionyl-CoA synthetase enzyme is part of the prpBCDE operon under the control of the PrpR regulatory protein, which needs 2-methylcitrate as a coactivator. Because the synthesis of 2-methylcitrate by PrpC (i.e., the 2-methylcitrate synthase enzyme) requires propionyl-CoA as a substrate, the level of propionyl-CoA needs to be raised by the Acs or PduW-Pta system before 2-methylcitrate can be synthesized and prpBCDE transcription can be activated.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Acyl Coenzyme A / metabolism*
  • Coenzyme A Ligases / metabolism
  • Escherichia coli Proteins*
  • Gene Expression Regulation, Bacterial*
  • Mutation
  • Operon
  • Phosphate Acetyltransferase / metabolism
  • Phosphotransferases (Carboxyl Group Acceptor) / metabolism
  • Propionates / metabolism*
  • Propylene Glycol / metabolism*
  • Salmonella enterica / genetics
  • Salmonella enterica / growth & development
  • Salmonella enterica / metabolism*
  • Sirtuins / genetics

Substances

  • Acyl Coenzyme A
  • Escherichia coli Proteins
  • Propionates
  • propionyl-coenzyme A
  • Propylene Glycol
  • Phosphate Acetyltransferase
  • Phosphotransferases (Carboxyl Group Acceptor)
  • TdcD protein, E coli
  • Sirtuins
  • Coenzyme A Ligases
  • propionate - CoA ligase