Phosphorylation and processing of the quorum-sensing molecule autoinducer-2 in enteric bacteria.

TitlePhosphorylation and processing of the quorum-sensing molecule autoinducer-2 in enteric bacteria.
Publication TypeJournal Article
Year of Publication2007
AuthorsXavier, KB, Miller, ST, Lu, W, Kim, JHwan, Rabinowitz, J, Pelczer, I, Semmelhack, MF, Bassler, BL
JournalACS Chem Biol
Date Published2007 Feb 20
KeywordsAdenosine Triphosphate, Enterobacteriaceae, Escherichia coli Proteins, Homoserine, Lactones, Magnetic Resonance Spectroscopy, Mass Spectrometry, Pentanes, Phosphorylation, Quorum Sensing, Receptors, Cell Surface, Repressor Proteins

<p>Quorum sensing is a process of chemical communication that bacteria use to assess cell population density and synchronize behavior on a community-wide scale. Communication is mediated by signal molecules called autoinducers. The LuxS autoinducer synthase produces 4,5-dihydroxy-2,3-pentanedione (DPD), the precursor to a set of interconverting molecules that are generically called autoinducer-2 (AI-2). In enteric bacteria, AI-2 production induces the assembly of a transport apparatus (called the LuxS regulated (Lsr) transporter) that internalizes endogenously produced AI-2 as well as AI-2 produced by other bacterial species. AI-2 internalization is proposed to be a mechanism enteric bacteria employ to interfere with the signaling capabilities of neighboring species of bacteria. We have previously shown that Salmonella enterica serovar Typhimurium binds a specific cyclic derivative of DPD. Here we show that following internalization, the kinase LsrK phosphorylates carbon-5 of the open form of DPD. Phosphorylated DPD (P-DPD) binds specifically to the repressor of the lsr operon, LsrR, consistent with P-DPD being the inducer of the lsr operon. Subsequently, LsrG catalyzes the cleavage of P-DPD producing 2-phosphoglycolic acid. This series of chemical events is proposed to enable enteric bacteria to respond to the presence of competitor bacteria by sequestering and destroying AI-2, thereby eliminating the competitors' intercellular communication capabilities.</p>

Alternate JournalACS Chem Biol
PubMed ID17274596
Grant ListAI 054442 / AI / NIAID NIH HHS / United States
GM 065859 / GM / NIGMS NIH HHS / United States