Team:Chiba/Project/Delay Switch

From 2009.igem.org

Revision as of 15:03, 10 September 2009 by Yoshimi (Talk | contribs)

Home

The Project


Delay Switch


Parallel Activation


Series Activation


Constructing A Delay Switch Since 2008

In principle, there are three ways to delay the activation of chemical communications;

  1. Silencing the Speakers: Rate of signal accumulation down-regulated, for instance, by slowing down the signal generators.
  2. Desensitize Receivers: Switching threshold elevated, for instance, by using insensitive receiver/ reporter systems.
  3. Partial Blocking: Decreasing the by chewing the signal up.

Inter-species communications! We decided to go for the strategy inspired by Japanese-classic experience; Whenever we speak to somebody in English, we often experience a certain delay in activating the communication. We though this is exactly what we pursued in. See Exp #4. Same applies to the reverse, too. When somebody speaks to us, we definitely need some time (sometime infinite) to get activated. This is all in spite that he/ she was loud and clear enough. The less affinity (perception) we have to English, the longer we need to activate them.See exp #5.

Experiments in 2008

For details, click each of the index titles

Exp #1 Partial quenching of signals (jamming)

The idea was that the effective concentration of AHL in receiver cell get significantly decreased due to the constantly expressing AiiA, thereby enlarging the delay time.

Exp #2 Balancing Player

In this section, we intended to create time-delay by altering the amount of luxR protein per cell. Since the amount of LuxR that receives AHL differs, we hypothesized that the time required to reach the threshold AHL concentration will differ.

To do this, we used different copy number plasmids of the Receivers.

Exp #4 Spoken to by Foreigners

In this plan, we induce cross-talk of quorum sensing by changing sender protein. This results in slower activation of receivers, when AHL concentration is increasing.

Exp #5 Speaking to Foreigners

In this plan, we induce cross-talk of quorum sensing by changing receiver protein. It is known that receiver proteins can work with the stimuli of signaling molecule even from another species of bacteria.

Experiments in 2009

Exp #3 Lux Mutants

Results