Team:Harvard/Dailybook/Week7/Widgetry

=Goals for this week=
 * Shewanella and E. coli co-culture experiments
 * If Shewanella responds rapidly to lactate, and E. coli breaks down lactose into lactate, can we couple lactose breakdown by E. coli with current production by Shewanella?
 * Motivation:
 * An inducible system in E. coli could be used to control Shewanella current production

=Monday: August 4, 2008=

Co-culture experiment setup

 * Chambers 1 & 2: wt E. coli + wt Shewie + lactose
 * Chambers 4 &5 : Lac-operon knockout E. coli + wt Shewie + lactose

Positive Controls
 * Chamber 3: wt E. coli + wt Shewie + lactate
 * Chamber 6: Lac-operon knockout E. coli + wt Shewie + lactate

Negative Controls
 * Chamber 7: wt Shewie + lactose
 * Chamber 8: wt E. coli + lactose
 * Chamber 9: Lac-operon knockout E. coli + lactose

=Tuesday: August 5, 2008=

Co-culture experiment results, day 1

 * [[Image: Co-culture_part1.JPG | 700 px]]
 * Notes:
 * At t = 2000 s, all cells added
 * At t = 80000 s, all injection done

Zoomed-in graph of results, part 1

 * [[Image: Co-culture_part1_zoomed.jpg | 700 px]]
 * Notes:
 * Zoomed-in on time since injections
 * Positive controls omitted

Preliminary Conclusions
 * Noticeable difference in behavior between wt E. coli + Shewie and Lac-operon knockout + Shewie co-cultures
 * Positive and negative controls show most likely no other variables involved
 * Could be used to create tic-tac-toe which uses the difference in behavior to determine moves

=Wednesday: August 6, 2008 to Friday: August 8, 2008=

wt E. coli vs. Lac-operon knockout E. coli

 * [[Image: Co-culture_part2_test.jpg | 700px]]
 * Notes:
 * At t = 260000 s, adjusted gas for Chamber 5
 * At t = 340000 s, lactose injection for Chamber 1
 * Initially, very noticeable difference between wt E. coli and Lac-operon knockout E. coli, but the current production of one of the E. coli chambers rises after a day, making the difference less distinguishable

Results w/ positive controls

 * [[Image: Co-culture_part2_wpos.jpg | 700px]]
 * Notes:
 * At t = 340000 s, lactose injections for Chambers 1, 3, and 6
 * Wanted to see if the positive controls would exhibit the same behavior when lactose injected instead of lactate

Results (entire)

 * [[Image: Co-culture_part2.jpg | 700px]]


 * Concerns
 * Chambers with co-cultures contained double the amount of cells of the controls
 * Current production in non-positive co-culture chambers
 * wt Shewie + lactose
 * lac-operon knockout E. coli + Shewie + lactose
 * lac-operon knockout E. coli + lactose


 * Conclusions
 * Although behavior of wt E. coli + Shewie and Lac-operon knockout E. coli + Shewie co-cultures are not as distinguishable after a day, our focus can only be on the first day
 * Will try the same experiment with DH5(alpha) and DH5(alpha)/pUC19 strains
 * Need to look for inducible lacZ systems
 * Light-repressible (RU1012 with plasmid) system?