# Presentation: 065879

## Small Talk

**Cell-to-Cell Communication**
**in Bacteria**

## Prokaryotic (Bacterial) Cells

- Prokaryotic (Bacterial) Cells

## Slide 3

## V. fischeri Quorum Sensing

**LuxI**

- Luciferase Genes

**LuxR**

**LuxR**

## Quorum Sensing In Bacteria

**LuxI**

- Target genes

**LuxR**

**LuxR**

## Acyl-Homoserine Lactone Autoinducers

- Acyl-Homoserine** **Lactone Autoinducers

## 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

## Slide 8

## Light

**LuxN**

**LuxQ**

**AI-1**

**AI-2**

**Luciferase Genes**

**Light**

- Quorum Sensing in *V. harveyi*

## V. harveyi Reporter Strain AI-1

**LuxN**

**AI-1**

**AI-2**

*V. harveyi *Reporter Strain AI-1

**Luciferase Genes**

**Light**

## Light

**LuxQ**

**AI-1**

**AI-2**

**Luciferase Genes**

**Light**

*V. harveyi *Reporter Strain AI-2

## Bacteria That Contain luxS

*Actinobacillus 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 O157:H7**	*
*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**	*

- Bacteria That Contain *luxS*

- (A sample of 534 genomes sequenced)

## Targets of AI-2

| Actinobacillus actinomycetemcomitans | Periodontal virulence, Mixed-species biofilms |
| --- | --- |
| Bacillus anthracis | Growth |
| Bacillus cereus | Biofilms |
| Bacillus subtilis | Development |
| Borrelia burgdorferi | Virulence |
| Campylobacter jejuni | Motility,  Toxins |
| Clostridium difficile | Virulence, Toxins |
| Clostridium perfringens | Virulence, Toxins |
| Escherichia coli K12 | AI-2 transport, Biofilms, Cell division, DNA  processing, Iron uptake |
| Escherichia coli EHEC O157:H7 | Virulence, Type III Secretion , Motility |
| Escherichia coli EPEC | Motility, Type III Secretion |
| Haemophilus influenzae | Virulence, Cell invasion |
| Helicobacter pylori | Motility, Biofilms |
| Klebsiella pneumoniae | Biofilms |
| Lactobacillus reuteri | Biofilms in mice |
| Listeria monocytogenes | Biofilms |
| Mannheimia haemolytica | Virulence, Encapsulation, Adhesion |
| Neisseria meningitidis | Virulence, Bacteremia |
| Photorhabdus luminescens | Antibiotic production |
| Porphyromonas gingivalis | Virulence, Proteases Hemin acquisition, Stress response |
| Salmonella typhi | Biofilms |
| Salmonella typhimurium | AI-2 transport, Biofilms |
| Serratia marcescens | Virulence in C. elegans, Hemolysin, Antibiotic production |
| Shigella flexneri | VirB (virulence factor) |
| Staphylococcus epidermis | Virulence, Biofilms |
| Streptococcus gordonii | Mixed-species biofilms |
| Streptococcus mutans | Virulence, Biofilms, Competence, Stress response |
| Streptococcus pneumoniae | Virulence, Persistence, Competence |
| Streptococcus pyogenes | Virulence factors, Protease, Hemolysin |
| Vibrio anguillarum | Protease |
| Vibrio cholerae | Virulence, Toxins, Biofilms |
| Vibrio fischeri | Bioluminescence, Colonization |
| Vibrio harveyi | Bioluminescence, Biofilms, Siderophore, Virulence, Type III Secretion, Protease |

## Inter-Species Communication

- 4,5-Dihydroxy-2,3-Pentanedione

- The Structure of AI-2

## Light

**LuxQ**

**AI-1**

**AI-2**

**Luciferase Genes**

**Light**

- Making Antibiotics Based on AI-2

## Making Antibiotics Based on AI-2

**AI-2**
**Analog**

**CHEMISTRY**

## No Light

**LuxQ**

**AI-2**

**Luciferase Genes**

**No Light**

- Making Antibiotics Based on AI-2

## Light

**LuxN**

**AI-1**

**Luciferase Genes**

**Light**

- Making Antibiotics Based on AI-2

## Making Antibiotics Based on AI-2

- Virulent  Bacteria

- Test Substance

- Feed

- Dead
- or
- Alive

## Quorum Sensing In Bacteria

- Bacteria Talk to Each Other

- Bacteria Distinguish Self from Other

*Opportunities for Novel Biotechnological Applications To*
*Impede/Enhance Quorum Sensing Controlled Functions*

- Quorum Sensing Allows Bacteria To Be Multi-Cellular
- Similar to Higher Organisms

*Many More Molecules Remain To Be Discovered*
*i.e., molecules that tell “who” the other is*

- Natural Anti-Quorum Sensing Strategies Already Exist

*Multiple Languages*
*i.e., intra- and inter-species communication*

## Slide 21