A Novel Protein Kinase That Controls Carbon Catabolite Repression in Bacteria

Mol Microbiol. 1998 Mar;27(6):1157-69. doi: 10.1046/j.1365-2958.1998.00747.x.

Abstract

HPr(Ser) kinase is the sensor in a multicomponent phosphorelay system that controls catabolite repression, sugar transport and carbon metabolism in gram-positive bacteria. Unlike most other protein kinases, it recognizes the tertiary structure in its target protein, HPr, a phosphocarrier protein of the bacterial phosphotransferase system and a transcriptional cofactor controlling the phenomenon of catabolite repression. We have identified the gene (ptsK) encoding this serine/threonine protein kinase and characterized the purified protein product. Orthologues of PtsK have been identified only in bacteria. These proteins constitute a novel family unrelated to other previously characterized protein phosphorylating enzymes. The Bacillus subtilis kinase is shown to be allosterically activated by metabolites such as fructose 1,6-bisphosphate and inhibited by inorganic phosphate. In contrast to wild-type B. subtilis, the ptsK mutant is insensitive to transcriptional regulation by catabolite repression. The reported results advance our understanding of phosphorylation-dependent carbon control mechanisms in Gram-positive bacteria.

Publication types

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

MeSH terms

  • Adenosine Triphosphate / pharmacology
  • Allosteric Regulation / physiology
  • Amino Acid Sequence
  • Bacillus subtilis / enzymology*
  • Bacillus subtilis / metabolism
  • Bacterial Proteins / chemistry
  • Enzyme Activation / physiology
  • Enzyme Inhibitors
  • Escherichia coli / genetics
  • Fructosediphosphates / pharmacology
  • Genome, Bacterial
  • Molecular Sequence Data
  • Phosphoenolpyruvate Sugar Phosphotransferase System / metabolism
  • Phosphorylation
  • Protein Kinase Inhibitors
  • Protein Kinases / chemistry*
  • Protein-Serine-Threonine Kinases*
  • Recombinant Proteins / chemistry
  • Sequence Alignment
  • Sequence Analysis

Substances

  • Bacterial Proteins
  • Enzyme Inhibitors
  • Fructosediphosphates
  • Protein Kinase Inhibitors
  • Recombinant Proteins
  • Adenosine Triphosphate
  • Protein Kinases
  • Phosphoenolpyruvate Sugar Phosphotransferase System
  • phosphocarrier protein HPr
  • HPr kinase
  • Protein-Serine-Threonine Kinases
  • fructose-1,6-diphosphate

Associated data

  • GENBANK/AF017113