Professor Chris Waters, Department of Microbiology and Molecular Genetics Michigan State University Drug Discovery Interdisciplinary Event

1. Hunting for PaNACEAs
Chris Waters
Department of Microbiology and Molecular Genetics

2. What would be the ideal activity for an anti-biofilm
compound?
+ Compound X
Potent and Novel Anti-biofilm Compounds that Enhance
Antibiotics (PaNACEAs)

3. Enhance tobramycin killing of P. aeruginosa biofilms
Tobramycin
• Aminoglycoside: binds to bacterial 30S
ribosomal subunit impairing protein
synthesis.
• Ototoxicity and nephrotoxicity
Cystic fibrosis

4. 384 Pin tool + 384-well growth plate
Rinse plate
Treatment plate +250 mg/mL tobramycin
(planktonic MIC-1 mg/mL)
Rinse plate
The PaNACEA Screening Protocol
BacTiterGlo

5. Summary of the pilot screen
Performed pilot screen of 6,080 biologically active compounds
at the Center for Chemical Genomics.
Z-factor 0.6 (very good for actual biofilms!)

6. TRICLOSAN
• Colgate Total= 0.3% = 10 mM
• Mechanism of action: inhibits fatty acid synthesisfabI
• P. aeruginosa known to be resistant

7. -20
0
20
40
60
80
100
120
CF11 CF13 CF78 CF99 CF101 CF144 CF153
PercentBiofilmKilling
P. aeruginosa CF Strain
Tri
Tob
Tri/Tob
Triclosan/Tobramycin effectively kills the biofilms of
19/19 clinical isolates tested

8. Before
treatment
Tobramycin Triclosan Water
Tobramycin
+Triclosan
P. aeruginosa 2.50E+08 7.61E+06 4.93E+06 7.39E+06 3.86E+03
1.0E+00
1.0E+01
1.0E+02
1.0E+03
1.0E+04
1.0E+05
1.0E+06
1.0E+07
1.0E+08
1.0E+09
CFU/mouse
Triclosan/Tobramycin effective in vivo

9. Future Directions
1. Screen the additional compounds libraries at the
CCG
2. Identify mechanism of triclosan
3. Further characterize additional PaNACEAs
4. Move triclosan/tobramycin treatment forward

10. Waters Lab
Alessandra Hunt, PhD
Will Soto, PhD
Eric Bruger
Nico Fernandez
Michael Maiden
Ben Pursley
Geoff Severin
Meng Shieh
Rudy Sloup
Jake Gibson
Charnay Gloss
Jenny Nyberg
John Shook
Alumni: Lauren Priniski!
CCG-University of Michigan
Martha Larsen
Tom McQuade
David Sherman
Pamela Schultz
Carl Averang
Avi Raveh
Princeton University
Martin Semmelhak
Wei-wei Lao
Jiaqiang Dong
Eric Kim