Display Settings:

Format

Send to:

Choose Destination
See comment in PubMed Commons below
J Biol Chem. 2009 Oct 9;284(41):28188-97. doi: 10.1074/jbc.M109.046334. Epub 2009 Aug 3.

Transcriptional activator YesS is stimulated by histidine-phosphorylated HPr of the Bacillus subtilis phosphotransferase system.

Author information

  • 1Laboratoire de Microbiologie et Génétique Moléculaire, INRA-AgroParisTech-CNRS, 78850 Thiverval-Grignon, France.

Abstract

In low GC content gram-positive bacteria, the HPr protein is the master regulator of carbon metabolism. HPr is a key component of the phosphoenolpyruvate (PEP):sugar phosphotransferase system that interacts with and/or phosphorylates proteins relevant to carbon catabolite repression. HPr can be phosphorylated by two distinct kinases as follows: the bifunctional enzyme HPr kinase/Ser(P)-HPr phosphorylase (HprK/P) phosphorylating the serine 46 residue (Ser(P)-HPr) and acting as a phosphorylase on Ser(P)-HPr; and the PEP-requiring enzyme I (EI) generating histidine 15-phosphorylated HPr (His(P)-HPr). The various HPr forms interact with numerous enzymes and modulate their activity. By carrying out a genome-wide yeast two-hybrid screen of a Bacillus subtilis library, we identified a novel HPr-interacting protein, the transcriptional activator YesS, which regulates the expression of pectin/rhamnogalacturonan utilization genes. Remarkably, yeast tri-hybrid assays involving the ATP-dependent HprK/P and the PEP-dependent EI suggested that YesS interacts with HPr and His(P)-HPr but not with Ser(P)-HPr. These findings were confirmed by in vitro interaction assays using the purified HPr-binding domain of the YesS protein. Furthermore, pectin utilization and in vivo YesS-mediated transcriptional activation depended upon the presence of His(P)-HPr, indicating that HPr-mediated YesS regulation serves as a novel type of carbon catabolite repression. In the yeast two-hybrid assays, B. subtilis HprK/P and EI were active and specifically recognized their substrates. Both kinases formed long lived complexes only with the corresponding nonphosphorylatable mutant HPr. These findings suggest that two-hybrid assays can be used for the identification of unknown kinases of phosphorylated bacterial proteins detected in phosphoproteome analyses.

PMID:
19651770
[PubMed - indexed for MEDLINE]
PMCID:
PMC2788870
Free PMC Article

Images from this publication.See all images (6)Free text

FIGURE 1.
FIGURE 2.
FIGURE 3.
FIGURE 4.
FIGURE 5.
FIGURE 6.
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Icon for HighWire Icon for PubMed Central
    Loading ...
    Write to the Help Desk