Rise of the machines: Bioengineers make working transistor from DNA

Bioengineers have moved a step closer to making a biological computer by fashioning working transistors out of genetic materials DNA and RNA.

 

The researchers, whose work was published in "Science," developed a three-terminal device architecture dubbed the "transcriptor" to do the job.

 

"We developed a three-terminal device architecture, termed the transcriptor, that uses bacteriophage serine integrases to control the flow of RNA polymerase along DNA. Integrase-mediated inversion or deletion of DNA encoding transcription terminators or a promoter modulate transcription rates," they said in their abstract.

 

Researchers in the study included Jerome Bonnet, Peter Yin, Monica Ortiz, Pakpoom Subsoontorn, and Drew Endy.

 

A separate article on ExtremeTech said this is one step closer to biological computers that can "detect changes in a cell’s environment, store a record of that change in memory made of DNA, and then trigger some kind of response."

 

Such responses may include "commanding a cell to stop producing insulin, or to self-destruct if cancer is detected," it said.

Biocomputers  

"Biological computers could tell their host cells to stop producing insulin, to pump out more adrenaline, to reproduce some healthy cells to combat disease, or to stop reproducing if cancer is detected. Biological computers will probably obviate the use of many pharmaceutical drugs," it said.

 

Just as transistors control the flow of electricity, transcriptors control the flow of RNA traveling along a strand of DNA.

 

ExtremeTech said this is done with special combinations of enzymes (integrases) that control the RNA’s movement along the strand of DNA.

 

Transcriptors, like transistors, also amplify signals, such that a small change in the enzyme’s activity can trigger a large change in two connected genes. Logic gates

 

Multiple transcriptors can be used to create Boolean Integrase Logic (BIL) gates, "the biological equivalent of AND, NAND, OR, XOR, NOR, and XNOR logic gates," it added.

 

“The choice of enzymes is important. We have been careful to select enzymes that function in bacteria, fungi, plants and animals, so that bio-computers can be engineered within a variety of organisms,” Bonnet said.

 

On the other hand, ExtremeTech said the work of other research groups can complement the new biological transistors have managed to store data in DNA.

 

Even Stanford has developed a way to use the M13 virus to transmit strands of DNA between cells.

 

Stanford contributed its BIL gate design to the public domain, allowing other research institutes, such as Harvard’s Wyss Institute to work on the first biological computer.

 

Biosensors 

 

ExtremeTech said people may soon expect to see —at least for now— simple biological sensors that can measure and record changes in a cell’s environment.

 

"We are essentially talking about fully-functional computers that can sense their surroundings, and then manipulate their host cells into doing just about anything. Biological computers might be used as an early-warning system for disease, or simply as a diagnostic tool," it said. — TJD, GMA News