The V. fischeri Autoinducer N-(b-ketocaproyl)-L-homoserine lactone

Quorum Sensing LuxI LuxR LuxR target gene

Acyl-Homoserine Lactone Autoinducers

LuxI-LuxR Quorum Sensing Systems V. fischeri P.aeruginosa A. tumefaciens E. carotovora Density dependent luminescence Virulence factors Conjugal transfer of Ti plasmid Antibiotic synthesis

Quorum Sensing in V. harveyi AI-2 LuxQ LuxP H D H D HTH LuxU LuxO H D LuxN AI-1 LuxR LuxCDABE

Quorum Sensing in E. coli and Salmonella

Bacteria That Contain luxS Klebsiella pneumoniae Lactococcus lactis Leuconostoc oenos Listeria monocytogenes Neisseria gonorrhoeae Neisseria meningitidis Pasteurella multocida Porphyromonas gingivalis Proteus mirabilis Salmonella paratyphi Salmonella typhi Salmonella typhimurium Bacillus anthracis Bacillus halodurans Bacillus subtilis Borrelia burgdorferi Campylobacter jejuni Clostridium acetobolyticum Clostridium difficile Clostridium perfringens Deinococcus radiodurans Escherichia coli Enterococcus faecalis Haemophilus influenzae Helicobacter pylori Shewanella putrefaciens Staphylococcus aureus Staphylococcus epidermidis Streptococcus gordonii Streptococcus mutans Streptococcus pneumoniae Streptococcus pyogenes Vibrio anguillarum Vibrio cholerae Vibrio harveyi Vibrio vulnificus Yersinia pestis

pfs metK luxS

MetK Pfs Page 544

SAM Utilization Met SAM SAH MTA SRH MTR 4,5-Dihydroxy- 2,3-pentanedione + HC ? MetK Pfs

SAM Utilization Met MetK SAM SAH MTA Pfs Pfs SRH MTR LuxS? 4,5-Dihydroxy- 2,3-pentanedione + HC ?

SAM Utilization Met MetK SAM SAH MTA Pfs Pfs SRH MTR LuxS AI-2 + HC ?

The LuxS Reaction 4,5-Dihydroxy- 2,3-pentanedione SRH + Homocysteine

AI-2 Could be a Furanone MHF DMHF HF DHCP

Quorum Sensing in V. harveyi AI-2 LuxQ LuxP H D H D HTH LuxU LuxO H D LuxN AI-1 LuxCDABE LuxR

Holo-LuxP

Boron is ubiquitous in the biosphere Sea water 0.4 mM (primarily boric acid) L.A. tap water 40 μM Soils 2-100 ppm Marine plants 120 ppm Land plants 50 ppm Marine animals 20-50 ppm Land animals 0.5 ppm Boron is required by a number of organisms, but for poorly characterized reasons Vascular plants cell wall? pollination? Diatoms Cyanobacteria heterocyst formation Zebrafish embryogenesis

11B NMR holo-LuxP filtered apo-LuxP

Synthesis of AI-2

Boric Acid Induces Lux in V. harveyi

Synthesis of AI-2

Targets of AI-2 Vibrio harveyi Bioluminescence, Biofilms Vibrio cholerae Virulence, Biofilms Salmonella typhimurium ABC transporter Salmonella typhi Biofilms Escherichia coli O157:H7 Type III Secretion (virulence) Porphyromonas gingivalis Hemin acquisition genes, virulence factors Shigella flexneri VirB (virulence factor) Streptococcus pyogenes Secreted protease Actinobacillus actinomycetemcomitans Periodontal virulence, Mixed-species biofilms Photorhabdus luminescens Antibiotic production Neisseria meningitidis Virulence/bacteremia Borrelia burgdorferi Virulence Clostridium perfringens Virulence Campylobacter jejuni Motility Microarrays Escherichia coli K12 ~300 genes Escherichia coli O157:H7 ~400 genes Vibrio cholerae El Tor ~70 genes (virulence regulon)

Biosynthesis of AI-1 and AI-2 Met MetK LuxI SAM LuxLM AI-1 SAH MTA Pfs Pfs SRH MTR LuxS AI-2 + HC ?

Quorum Sensing in V. harveyi AI-2 LuxQ LuxP H D H D HTH LuxU LuxO H D LuxN AI-1 LuxCDABE LuxR