A biosynthetic dual-core cell computer

ETH researchers have integrated two CRISPR-Cas9-based core processors into human cells. This represents a huge step towards creating powerful biocomputers.

A team of researchers led by Martin Fussenegger, Professor of Biotechnology and Bioengineering at the Department of Biosystems Science and Engineering at ETH Zurich in Basel, have now found a way to use biological components to construct a flexible core processor, or central processing unit (CPU), that accepts different kinds of programming. The processor developed by the ETH scientists is based on a modified CRISPR-Cas9 system and basically can work with as many inputs as desired in the form of RNA molecules (known as guide RNA).

A special variant of the Cas9 protein forms the core of the processor. In response to input delivered by guide RNA sequences, the CPU regulates the expression of a particular gene, which in turn makes a particular protein. With this approach, researchers can program scalable circuits in human cells – like digital half adders, these consist of two inputs and two outputs and can add two single-digit binary numbers.

The researchers took it a step further: they created a biological dual-core processor, similar to those in the digital world, by integrating two cores into a cell. To do so, they used CRISPR-Cas9 components from two different bacteria. Fussenegger was delighted with the result, saying: "We have created the first cell computer with more than one core processor."

This biological computer is not only extremely small, but in theory can be scaled up to any conceivable size. "Imagine a microtissue with billions of cells, each equipped with its own dual-core processor. Such 'computational organs' could theoretically attain computing power that far outstrips that of a digital supercomputer – and using just a fraction of the energy," Fussenegger says.