Some clever biochemistry has led to the worlds first enzyme-based memory capable of learning, say biochemists

Electronic processors are highly efficient at certain types of computation. For example, a standard PC can vastly outperform any human at arithmetic. However, computer scientists have long been fascinated by the ability of biological systems to do tasks, such as face recognition, at speeds and a power efficiency that put the most powerful supercomputers to shame.

Clearly, biology is able of computing in ways that traditional processors have failed to capture, which is why there is a significant interest in unconventional methods of computing that explore new ways of processing information.

One form of unconventional computing is biochemical and involves using molecules to encode information and using chemical reactions to process it. Nature has developed highly complex machinery for doing this so much of the focus has been on exploiting biological molecules for this task, using proteins, DNA and the like.

Today,Vera Bocharova and a few pals at Clarkson University in Potsdam, New York, say they ve used a set of enzymes to create a memory system that can learn to produce a specific output given a certain input. They says this system can even unlearn again later. We report the first realization of a simple variant of associative memory in an enzymaticbiochemical process, they say.

The theory is straightforward. Imagine the system as a black box that can have two chemical inputs and a chemical output. This output is a chemical called oxidised3,3,5,5-tetramethylbenzidine (TMB).

The black box produces oxidised TMB when it receives input 1 but the goal is to make it produce oxidised TMB when it receives input 2. In other words, Bocharova and co aim to teach the system to produce oxidised TMB when it senses input 2.

The trick theyve perfected is one of chemistry. Input 1 alone produces oxidised TMB. But Bocharova and co have designed the chemistry so that when input 1 and 2 are added together, the result is a chemical environment that is ripe for the production of oxidised TMBbut only when they add more of input 2.

So having added input 1 and 2 togetherhaving trained the systemit is now ready to produce oxidised TMB when it receives input 2 alone. The system has learned to respond to input 2.

Original post:
First Enzyme-Based Memory Created in the Lab