How Far Have We Gotten?

Dr. Karmella Haynes and Samantha Simpson ('09) Continued Flipping



Convert Constructs to Numerical Symbols
Flippable Promoter (1) or (-1)
Flippable Tetracycline resistance (2) or (-2)



Unexpected Problems = opportunities to learn more



Position Matters for RBS




It Flips Too Fast!



Needed Two Plasmids to Reduce Hin Production; Remove RE

Pancakes in pSB1A7
Hin in pSB3K3




Test Predictions with Biological Reality




Needed Insulated Plasmid





Biological Equivalents

(1, 2) = (-2, -1)

Distinguish 1,2 from -2, -1



pBad is a Weak Promoter




pLac Promoter and Tetr Reveal Secrets

White Colonies Live on Tet Plates
Faint Pink Colonies Live on Tet Plates
Cells Die
Red Colonies Live on Tet Plates




4 PCR Primers Detect 4 Possible Orientations




4 PCR Primers to Detect 4 Possible Combinations



Screen Colonies for Flipping Order



One Flip Before Two Flips, No Size Preference




Hin Can Flip (-2, 1) to (-1, 2)

White Light
UV Light



What have we gained, besides having fun and learning a lot?

Cross-trained students in biology and math/CS

Understand: Promoters, Reporter Strengths, Critical Parts, and System Behavior

Successfully built biological computer

Produce better transgenic organisms?

Biological digital data storage (0's and 1's) device?

Massively parallel computation as cheap as an undercooked hamburger!


Biology Department

© Copyright 2007 Department of Biology, Davidson College, Davidson, NC 28036
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