Synthetic Biology: PTL Logic

Post-Translational Logic (PTL) devices regulate the post-translational modifications of proteins to define system state and control cell function. Current synthetic biological circuits make use of protein-DNA and RNA-RNA interactions to control gene expression in bacteria– such circuits are examples of Transcription-based Logic.

This is an area where Samantha Sutton of MIT is a leading researcher.
The BioBricks Foundation awarded Samantha Sutton the prize of Best Device at the Synthetic Biology 2.0 confernce. Sutton works in the Endy Lab.

A brief comparison of the two types of logic is as follows:

Transcription-based Logic

* Engineered around gene expression
* Typical parts: transcriptional regulators, translational regulators
* Typical signal: PoPS, resulting in desired cellular concentrations of proteins.
* Easier to engineer than PTL
* Slow response time (hours)
* Uses one subset of cellular functions


* Engineered around protein modifications
* Typical parts: kinases, phosphorylation sites, docking sites
* Typical signal: rate of modification, resulting in desired state of proteins.
* More difficult to engineer than Transcription-based logic.
* Fast response time (seconds)
* Explores a new set of applications

Openwetware community portal is a place where synthetic biology information is shared

Openwetware has tutorials, Materials used, and equipment at various labs

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