2.  Bacteria constantly release signal molecules  If cell density is not big enough  nothing happens  Threshold density  all bacteria simultaneously carry out gene expression  “Quorum Sensing” from counting as to take a vote before acting

3.  Acyl homoserine lactones (AHL molecules)  Easy transport of molecules outside of cells

5.  Precursor Oligopeptides  Must be exported via active transport proteins

7.  Al-2 molecule is universal  Produced by LuxS enzyme from dihydroxy pentanedione substrate

9.  Microorganisms form layer with proteins, DNA and long chain sugars  Often pathogenic  Concern for health and food industry ◦ Spoiled food ◦ Biofilms in cystis fibrosis  Quorum sensing plays big role in the high cell density communication and virulence

12.  Scientists are investigating varied bio-film formations and mutations that could help decrease formation  Looking at mutant luxS enzymes and other quorum sensing systems  Disrupt quorum sensing  disrupt biofilm formation and virulence

14.  Benign epithelial brain tumor common in children  Cannot spread but presses on vital structures  Can cause stunted growth, obesity, diabetes insipidus, and other morbidity  Hard to remove due to strong adherence to important structures  Often reoccurs

15.  Ep-CAM gene expression is highly over expressed  Produces Ep-CAM glycoprotein adhesion molecule  Is linked to tumor genesis and metastasis  Makes tumor strongly adherent

17.  Radiotherapy ◦ Kills healthy cells ◦ High risk of second cancer in children and adolescents

18.  Silencing Ep-CAM gene by inhibiting transcription through methylation of the promoter region

19. Aerotolerant E.Coli bacteria engineered to produce invasin protein and produce m5c DNA methyltransferase enzymes on signal Calcification material Ep-CAM glycoprotein Receptor

20. m5c methyltransferase enzymes Invasin proteins Bacteria Produces

21. B-1 Integrin receptor Tumor cell Invasin Proteins

22. Ep-CAM promoter M5c DNA methyltrasnferase enzymes

23. RNA Polymerase Ep-CAM Transcription

24. Ep-CAM glycoproteinCalcium depositsm5c methyltransferase production 000 010 100 111

25. Methylated CpG Islands on Promoter Ep-CAM Expression 01 10

26.  No damage to healthy cells  Easy to administer  No radioactive material  Helps surgeons remove tumor  Decrease reoccurrence

27.  Ep-CAM promoter region specific methylation  Laboratory precaution while working with cells with invasin  Precautions to keep bacteria from evolving and reproducing out of control

28.  Testing on tissue culture and many other steps before reaching human testing  Similar system could be tweaked and developed for other cancers