| Abstract |
Undecaprenyl phosphate (C55P) is an essential sugar carrier for bacterial cell wall synthesis, which has gained importance in recent years as a promising target for new antibiotic development. In Escherichia coli, C55P is produced by dephosphorylation of undecaprenyl diphosphate (C55PP) by BacA and two type 2 phosphatidic acid phosphatase (PAP2) family enzymes, PgpB and YbjG, in the periplasmic space. To clarify the regulatory mechanism of C55PP dephosphorylation, we quantified C55P and C55PP using a new high-performance liquid chromatography method, conducted susceptibility tests against bacitracin, and analyzed the gene expression of bacA, pgpB, and ybjG in E. coli single- and double-disruption strains of those genes. C55P levels were similar in all strains, but C55PP levels increased only in the bacA, ybjG double-disruption strain. The double-disruption strains containing bacA disruption and the bacA single-disruption strain were more susceptible to bacitracin than the other strains. In the double-disruption strains containing bacA disruption, the expression of the remaining genes pgpB and ybjG increased. These results indicate that the transcription of the PAP2 family enzyme genes, pgpB and ybjG, was activated under conditions where C55PP dephosphorylation activity in cells was reduced. This transcriptional regulation might contribute to the maintenance of C55P levels in cells.
|
