Describe cellular communication systems used
Las/Rhl cell signaling system
Responsible: Robert Cool, Alicia Allen, and Erin Feeney
Signal Molecule: An AHL called PAI-1 (N-3-oxododecanoyl-l-hsl)(3-oxo-C12-hsl)
Bacterial species: Pseudomonas aeruginosa gram(-) possibly E.coli (see article 3)
Receiver protein: LasR
Effect of binding: TXN activation of virulence genes, lasA, lasB, apr, toxR
Synthase: LasI enzyme
Target Genes: lasI, lasA, lasB, apr, toxR
"Roles of Pseudomonas aeruginosa las and rhl quorum-sensing systems in control of elastase and rhamnolipid biosynthesis genes"
JP Pearson, EC Pesci and BH Iglewski 
"Regulation of Pseudomonas Quinolone Signal Synthesis in Pseudomonas aeruginosa"
Dana S. Wade, M. Worth Calfee, Edson R. Rocha, Elizabeth A. Ling, Elana Engstrom, James P. Coleman, and Everett C. Pesci 2
Posttranscriptional Control of Quorum-Sensing-Dependent Virulence Genes by DksA in Pseudomonas aeruginosa
Florence Jude,Thilo Köhler,Pavel Branny,Karl Perron,Matthias P. Mayer,Rachel Comte, and Christian van Delden 3
Signal Molecule: An AHL called PAI-2, Plasminogen activator inhibitor-2, N-butanoyl-homoserine lactone (C4HSL)
Bacterial species: Pseudomonas aeruginosa, gram(-)
Receiver Protein: Rhl R
Effect of Binding: activation of Rhamnosyl Transferase, then making RL (rhamnolipid)
Synthase: RhlA and RhlB
Target Genes: pqsABCDE and phnAB
Lux cell signaling system
Responsible: Andrew Gordon and Pallavi Penumetcha
Signal molecule: N-acyl-homoserine lactone (AHL) Generic term for a variety of species specific hormone-like molecules
Bacterial species: discovered in Vibrio fischeri known to work in E. coli
Receiver protein: LuxR protein receives signal from AHL; also has some control over transciption of luciferase
Signal molecule synthase: LuxI; also has some control over transciption of luciferase
Additional Information: "Quorum Quenching" aiiA (intracellular) lactonase reduces AHL concentration
 A Synthetic multicellular system for programmed pattern formation
Lsr (AI-2) cell signaling system
Responsible: Kelly Davis, Xiao Zhu
Signal molecule: AI-2 (furanosyl borate diester in V. harveyi, a variety of other molecules in other species), all are derived from DPD. AI-2 is R-THMF in E. coli
lsrA,B,C,D,F,G,R,K: Escherichia coli HS, SMS-3-5, str. K12 substr. MG1655, and substr. DH10B.
lsrE:Escherichia coli str. K12 substr. MG1655
LuxS:Escherichia coli HS, SMS-3-5, APEC O1, str. K12 substr. MG1655, substr. DH10B, and UTI89.
Receiver protein: LsrR protein receives signal from sensor protein
Signal molecule synthase: Pfs enzyme, then LuxS autoinducer synthase
Target genes: lsr operon, including ABC transporter and LsrK kinase
Regulation: LsrR represses the lsr operon, derepression by phospho-AI-2; catabolite repression influences AI-2 accumulation through the cyclic AMP (cAMP)-cAMP receptor protein (CRP) complex, which directly stimulates transcription of the lsr operon and indirectly represses luxS expression.cAMP-CRP is shown to bind to a cAMP receptor protein (CRP) binding site located in the upstream region of the lsr promoter and works with the LsrR repressor to regulate AI-2 uptake.
Note: AI-2 is synthesized and secreted during exponential growth and is imported in stationary phase when glucose becomes limiting. In the presence of glucose, AI-2 is not imported because the lsr operon is not transcribed due to camp-CAP mediated repression. Both glycerol and G3P(glycerol 3-phosphate) repress lsr transcription, while the majority repression comes from G3P. DHAP represses lsr transcription by a cAMP-CAP-independent mechanism involving LsrR.
lsrB encodes the periplasmic AI-2 binding protein
lsrC & lsrD encode the channel proteins
lsrA encodes the ATPase that provides energy for AI-2 transport
lsrF is similar to genes specifying aldolases
lsrG encodes a protein with an unknown function.
DHAP: dihydroxyacetone phosphate.
Transcription of LuxS (interaction with micA,gshA)