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Contents 1 Intro 2 Principle 3 Approaches 3.1 The 'Cell Duplication' approach 3.2 The 'Single Oscillator' approach 3.3 The 'Beat' approach 3.4 Alternative approach 4 Discussion 4.1 Questions: 4.2 Remarks: 4.3 Ideas: 4.4 Critics:

Intro

When you think about Switzerland the first things you associate with this country may be chees, chocolate and of course watches. So a bacterial Swiss watch would be cool to develop.

Principle

The idea is to develop a relative fast and mainly robust and precise (otherwise it wouldn't be a swiss watch ;-)) triggering of at least 2 different output signals in order to distinguish between minutes and hours (as the processes are not so fast it will be more likely hours and days).

Approaches

The 'Cell Duplication' approach

As bacterias duplicate themselfes rather fast and in periodic intervals - as long as the environmental conditions allow it - one could use the duplication for triggering an output. For example the DnaA protein or the concentration of the produced mioC and oriC respectivly could be such triggering substances (see paper on 'Transcriptional control for initiation of chromosomal replication in Escherichia coli'). This approach could also be used as a kind of a 'Generation Counter'.

The 'Single Oscillator' approach

With a stable and robust oscillator (see paper 'Development of genetic circuitry exhibiting toggle switch or oscillatory behavior in Escherichia coli') one could rather easily implement a watch by just counting the peaks (see also 'Oscillation Counter').

The 'Beat' approach

With the combination of two oscillators of different frequencies one could establish a kind of a beat. One oscillator could be used as the 'minute hand' and the when the beat reaches its maximum the 'short hand' gives an impulse.

Alternative approach

The focus of the project could be reduced to creating an oscillator that is simple, robust, and very regular. To make things even more attractive, one could build a quorum sensing component that synchronizes the whole population. (Strange, i think i already saw something like that somewhere in the registry of biological parts, does anybody have an idea?)

Discussion

Questions:

Remarks:

Ideas:

Critics:

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