Evidence of link between quorum sensing and sugar metabolism in Escherichia coli revealed via cocrystal structures of LsrK and HPr

Sci Adv. 2018 Jun 1;4(6):eaar7063. doi: 10.1126/sciadv.aar7063. eCollection 2018 Jun.


Quorum sensing (QS), a bacterial process that regulates population-scale behavior, is mediated by small signaling molecules, called autoinducers (AIs), that are secreted and perceived, modulating a "collective" phenotype. Because the autoinducer AI-2 is secreted by a wide variety of bacterial species, its "perception" cues bacterial behavior. This response is mediated by the lsr (LuxS-regulated) operon that includes the AI-2 transporter LsrACDB and the kinase LsrK. We report that HPr, a phosphocarrier protein central to the sugar phosphotransferase system of Escherichia coli, copurifies with LsrK. Cocrystal structures of an LsrK/HPr complex were determined, and the effects of HPr and phosphorylated HPr on LsrK activity were assessed. LsrK activity is inhibited when bound to HPr, revealing new linkages between QS activity and sugar metabolism. These findings help shed new light on the abilities of bacteria to rapidly respond to changing nutrient levels at the population scale. They also suggest new means of manipulating QS activity among bacteria and within various niches.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Bacterial Proteins / chemistry
  • Bacterial Proteins / metabolism*
  • Carbohydrate Metabolism
  • Enzyme Activation
  • Escherichia coli / physiology*
  • Escherichia coli Proteins / chemistry
  • Escherichia coli Proteins / metabolism*
  • Gene Expression Regulation, Bacterial
  • Kinetics
  • Models, Molecular
  • Phosphoenolpyruvate Sugar Phosphotransferase System / chemistry
  • Phosphoenolpyruvate Sugar Phosphotransferase System / metabolism*
  • Phosphotransferases (Alcohol Group Acceptor) / chemistry
  • Phosphotransferases (Alcohol Group Acceptor) / metabolism*
  • Promoter Regions, Genetic
  • Protein Binding
  • Protein Conformation
  • Quorum Sensing*
  • Recombinant Proteins / chemistry
  • Recombinant Proteins / metabolism
  • Structure-Activity Relationship
  • Sugars / metabolism*


  • Bacterial Proteins
  • Escherichia coli Proteins
  • Recombinant Proteins
  • Sugars
  • LsrK protein, E coli
  • Phosphoenolpyruvate Sugar Phosphotransferase System
  • Phosphotransferases (Alcohol Group Acceptor)
  • phosphocarrier protein HPr