Identification of triphosphoribosyl-dephospho-CoA as precursor of the citrate lyase prosthetic group

FEBS Lett. 2000 Oct 20;483(2-3):165-8. doi: 10.1016/s0014-5793(00)02105-0.


The gamma-subunit of citrate lyase (EC contains the prosthetic group 2'-(5"-phosphoribosyl)-3'-dephospho-CoA and serves as an acyl carrier protein (ACP). We recently showed that in Escherichia coli the proteins CitG and CitX are essential for holo-ACP synthesis and provided evidence that CitG catalyzes the formation of a prosthetic group precursor from ATP and dephospho-CoA, which is subsequently attached via phosphodiester linkage to apo-ACP by CitX. Here we prove that CitG indeed catalyzes the conversion of ATP and dephospho-CoA to adenine and 2'-(5"-triphosphoribosyl)-3'-dephospho-CoA, the predicted precursor of the prosthetic group. Furthermore, this precursor was transferred by CitX to apo-ACP, yielding holo-ACP. Thus, our proposed mechanism for holo-ACP synthesis could be verified.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • ATP Citrate (pro-S)-Lyase / chemistry
  • ATP Citrate (pro-S)-Lyase / metabolism*
  • Acyl Carrier Protein / metabolism
  • Adenosine Triphosphate / metabolism
  • Apoenzymes / metabolism
  • Chromatography, High Pressure Liquid
  • Coenzyme A / metabolism*
  • Electrophoresis, Polyacrylamide Gel
  • Enzyme Precursors / metabolism
  • Escherichia coli / enzymology
  • Holoenzymes / metabolism
  • Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization


  • Acyl Carrier Protein
  • Apoenzymes
  • Enzyme Precursors
  • Holoenzymes
  • dephosphocoenzyme A
  • Adenosine Triphosphate
  • ATP Citrate (pro-S)-Lyase
  • Coenzyme A