Paris/July 8

From 2007.igem.org

yesterday -- tomorrow

Growth kinetics of w121 strain

We make an array to test growth of w121 on different growth media (LB, S0.2, S0.4, S0.6, S0.8), supplemented with different amount of DAP.

Two questions are addressed by the following assay:

  • What is the growth behaviour of w121 (dapA- strain) at different concentrations of DAP?
  • How does w121 strain grow on filtrates of MG1655 growth medium; that is, does MG1655 secrete DAP during growth?

MG1655 was grown on LB medium and the growth medium was filtered free of bacteria at different DO (Optical Densities) during exponential growth phase:

S0.2 (at DO=0.2) S0.4 S0.6 S0.8


W121 was grown on different media:


LB line B in the array S0.2 (at DO=0.2) line C in the array S0.4 line D & E in the array S0.6 line F in the array S0.8 line G in the array

In the different columns, DAP was added to the indicated final concentrations (without taking into account DAP produced by MG1655 regarding the recycled growth media)


Kinetic Array :w121 kinetic as a function of DAP and supplemented medium (S0.x)
1 2 3 4 5 6 7 8 9 10 11 12
A H20 H20 H20 H20 H20 H20 H20 H20 H20 H20 H20 H20
B H20 LB+0µM DAP LB+13µM DAP LB+17µM DAP LB+20µM DAP LB+23µM DAP LB+27µM DAP LB+30µM DAP LB+33µM DAP LB+37µM DAP LB+40µM DAP H20
C H20 S0.2+0µM DAP S0.2+13µM DAP S0.2+17µM DAP S0.2+20µM DAP S0.2+23µM DAP S0.2+27µM DAP S0.2+30µM DAP S0.2+33µM DAP S0.2+37µM DAP S0.2+40µM DAP H20
D H20 S0.4+0µM DAP S0.4+13µM DAP S0.4+17µM DAP S0.4+20µM DAP S0.4+23µM DAP S0.4+27µM DAP S0.4+30µM DAP S0.4+33µM DAP S0.4+37µM DAP S0.4+40µM DAP H20
E H20 S0.4+0µM DAP S0.4+13µM DAP S0.4+17µM DAP S0.4+20µM DAP S0.4+23µM DAP S0.4+27µM DAP S0.4+30µM DAP S0.4+33µM DAP S0.4+37µM DAP S0.4+40µM DAP H20
F H20 S0.6+0µM DAP S0.6+13µM DAP S0.6+17µM DAP S0.6+20µM DAP S0.6+23µM DAP S0.6+27µM DAP S0.6+30µM DAP S0.6+33µM DAP S0.6+37µM DAP S0.6+40µM DAP H20
G H20 S0.8+0µM DAP S0.8+13µM DAP S0.8+17µM DAP S0.8+20µM DAP S0.8+23µM DAP S0.8+27µM DAP S0.8+30µM DAP S0.8+33µM DAP S0.8+37µM DAP S0.8+40µM DAP H20
H H20 H20 H20 H20 H20 H20 H20 H20 H20 H20 H20 H20


The 96 well plate is surrounded by H2O in order to maintain humidity during the assay. In each slot, 200µL of the growth medium (LB or S0.x) is mixed with 2µL of w121 culture grown ON, and with different amount of DAP (see table). The growth profile is measured over a period of 20H, a DO measurement is acquired each 4min10s.

Results of previous day kinetics

Y axis : Optical Density. Paris Graph1 w121 070707.jpg Paris Graph2 w121 070707.jpg