The microscopic computer uses enzymes as hardware, which in turn manipulates DNA molecules as software, creating a single mathematical computing machine, called a finite automaton.

The "biological nanocomputer" was created by a group of scientists headed by Ehud Shapiro, a professor at the Weizmann Institute of Science, which announced the development.

"The living cell contains incredible molecular machines that manipulate information-encoding molecules ... in ways that are fundamentally very similar to computation," Shapiro said.

Another expert expressed both caution and optimism.

"Using the term 'computer' is actually a bit misleading," said professor Naftali Tishbi of the Hebrew University, a scientist familiar with the group's work.

Tishbi defined the cells as automatons, meaning they operate according to preset reactions, but he said the invention is "a very exciting step toward plausible DNA computing."

The creators of the device said that the trillion cells, acting together, can perform a billion operations per second, with 99.8 percent accuracy. The trillion cells require less than a billionth of a watt of power to operate.

Although the nanocomputer doesn't have any practical use at the moment, scientists claim it has enormous potential. "Such a future computer could sense an abnormal biochemical change in the body and decide how to correct it by synthesizing and releasing the necessary drug," said professor Zvi Livneh, a DNA expert at the Weizmann Institute.

Tishbi said the automatons could soon prove to be useful by detecting anomalies while operating within human DNA.

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