Small Talk

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Small Talk Cell-to-Cell Communication in Bacteria
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Prokaryotic (Bacterial) Cells
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V. fischeri Quorum Sensing
LuxR
LuxI
LuxR
Luciferase Genes
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Quorum Sensing In Bacteria
LuxR
LuxI
LuxR
Target genes
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Acyl-Homoserine Lactone Autoinducers
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LuxI-LuxR Quorum Sensing Systems
V. fischeri P. aeruginosa A. tumefaciens E.
carotovora
Bioluminescence Virulence Factors,
Biofilms Mating, Transfer of Mobile
DNA Virulence Factors, Antibiotic Synthesis
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Quorum Sensing in V. harveyi
LuxQ
AI-2
Luciferase Genes
AI-1
Light
LuxN
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V. harveyi Reporter Strain AI-1
AI-2
Luciferase Genes
AI-1
LuxN
Light
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V. harveyi Reporter Strain AI-2
LuxQ
AI-2
Luciferase Genes
AI-1
Light
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Quorum Sensing in E. coli and Salmonella
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Bacteria That Contain luxS
(A sample of 534 genomes sequenced)
Actinobacillus actinomycetemcomitans Actinobacillu
s pleuropneumoniae Actinobacillus suis Bacillus
anthracis Bacillus halodurans Bacillus
subtilis Borrelia burgdorferi Campylobacter
jejuni Clostridium acetobutylicum Clostridium
difficile Clostridium perfringens Deinococcus
radiodurans Escherichia coli MG1655 Escherichia
coli O157H7 Enterococcus faecalis Haemophilus
influenzae Helicobacter pylori Klebsiella
pneumoniae Lactococcus lactis Leuconostoc
oenos Listeria monocytogenes Mannheimia
haemolytica
Neisseria gonorrhoeae Neisseria
meningitidis Pasteurella multocida Pasteurella
trehalosi Porphyromonas gingivalis Proteus
mirabilis Salmonella paratyphi Salmonella
typhi Salmonella typhimurium Shewanella
putrefaciens Shigella flexneri Staphylococcus
aureus Staphylococcus epidermidis Streptococcus
gordonii Streptococcus mutans Streptococcus
pneumoniae Streptococcus pyogenes Vibrio
cholerae Vibrio harveyi Vibrio
parahaemolyticus Vibrio anguillarum Vibrio
vulnificus Yersinia pestis
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Targets of AI-2
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Quorum Sensing in V. harveyi
LuxQ
AI-2
Luciferase Genes
AI-1
LuxN
Light
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Inter-Species Communication The Structure of AI-2
4,5-Dihydroxy-2,3-Pentanedione
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Making Antibiotics Based on AI-2
LuxQ
AI-2
LuxS
Luciferase Genes
AI-1
LuxN
Light
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Making Antibiotics Based on AI-2
CHEMISTRY
AI-2
AI-2 Analog
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AI-2 Quorum Sensing in V. harveyi
LuxQ
AI-2
Luciferase Genes
No Light
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AI-1 Quorum Sensing in V. harveyi
Luciferase Genes
AI-1
Light
LuxN
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Making Antibiotics Based on AI-2
Test Substance
Dead or Alive
Inject
Virulent Bacteria
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Quorum Sensing In Bacteria
Bacteria Talk to Each Other
Multiple Languages i.e., intra- and inter-species
communication
Bacteria Distinguish Self from Other
Many More Molecules Remain To Be Discovered i.e.,
molecules that tell who the other is
Quorum Sensing Allows Bacteria To Be
Multi-Cellular Similar to Higher Organisms
Opportunities for Novel Biotechnological
Applications To Impede/Enhance Quorum Sensing
Controlled Functions
Natural Anti-Quorum Sensing Strategies Already
Exist
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