New York (PTI): Scientists have developed "designer enzymes" which they claim will have applications for defense against biological warfare and for creating more effective medications.

According to them, the designer enzymes are created for a chemical reaction called the Kemp elimination which is a non-natural transformation in which hydrogen is pulled off a carbon atom.

"The design of new enzymes for reactions not normally catalysed in nature is finally feasible. The goal of our research is to use computational methods to design the arrangement of groups inside a protein to cause any desired reaction to occur," said lead researcher Prof Kendall Houk.

Prof Houk of University of California and his fellow researchers at the Washington University used algorithms and supercomputers to design the active site for the enzymes -- the area in which the chemical reactions take place.

Then they used their computer programmes to design a sequence of amino acids that folded to produce an active site like the one designed.

Subsequently, the scientists determined the precise three-dimensional arrangement of these chemical groups, which is critical for the specificity and activity of the designer enzymes with an accuracy of less than a hundredth of nanometre.

"Previous reports of designed enzymes have not been very successful, and some have been withdrawn. That is hardly surprising, considering the challenge of designing in days or weeks what nature has perfected over years of evolution.

"Enzymes are the ultimate 'green' catalysts by performing under ambient conditions in water. This technology will find tremendous applications," Prof Houk was quoted by the 'ScienceDaily' as saying.

Added co-researcher Jason DeChancie, "The rate enhancements by our designer enzymes are modest and hardly competitive, so far, with those observed for their natural counterparts. We hope with improvements in technology, we can close the gap between designer enzymes and natural enzymes."