Revision as of 04:01, 18 November 2007

Logic Gates in Synthetic Biology

Background: Logic Gates and Truth Tables

A logic gate is a computing unit that performs a logical operation on one or more inputs and produces a single output. Gates are identified by their function, and each type of logic gate can be represented with a distinctive symbol. The inputs are represented with short line segments to the left of the shape, and the output is represented by a short line segment to the right of the shape. A small circle on the right indicates that the output of the logical operation is inverted. Here are a few examples:

A truth table is a useful way to describe the behavior or function of a logic gate. A "1" is used for "true" or a positive input, and a "0" is used for "false" or a negative input.

Logic Gates in Synthetic Biology

Engineering Principles

1. Standardization of parts
2. Component abstraction
3. Separation of system design from system fabrication

Biomolecular logic gates can be used as "parts" in the design of synthetic gene circuits.

Biomolecular Logic Gates

In vitro studies have been used to design combinations of molecules that have emergent properties related to information processing--molecular computing devices. The extent to which these devices will be used with the cellular context is unclear--however, they are bound to inspire new directions for research in synthetic biology.

Computing with Enzymes

Baron et al.

Ribozyme-Based Logic Gates

Stojanovic and Stephanovic

DNA Self-Assembly

Yan et al. (Reif)

Other Molecular Systems

Ghadiri, de Silva

Cellular Logic Gates

Methods

Examples

Applications and Future Directions

Synthetic gene circuits - use multiple simple input-output logic systems to design and build more complex circuits.

Medical applications - Increase specificity with which bacteria can sense an environment by combining multiple environmental inputs in logic gates. Autonomous biomolecular computing devices - use for molecular-level diagnostics and treatment

References

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