Metabolic Engineering: kinetics 3

The last highly oversimplified computer simulation is Exercise 3, FEEDBAK.BAS, that shows how feedback control overcomes a change in a rate coefficient. Again a mutation that impairs a rate is not necessarily lethal. The cell may carry on with little impairment while the biochemical of industrial interest accumulates. The reaction sequences are:


The green circles show the biochemical feedback. The coefficients being maniplated are k2 and k4. Try various permutations with this applet: (RED for C, GREEN for E)


This time the graphs have several interesting features:
  • a large change in an earlier rate coefficient has little effect on the biochemical that has its concentration feeding back to control an earlier rate,
  • an earlier intermediate has its concentration greatly effected,
  • when either rate is selected, effects of the other are minimal over fairly wide ranges.
    The dynamics of reaching equilibrium are not realistic, but the final concentrations demonstrate the principles.

    End of this topic.


    bungay@rpi.edu while on sabbatical leave in Porto, Oct. 1996