New enzyme fights nerve gas

A group of scientists at the Weizmann Institute of Science in Rehovot, Israel, have developed an enzyme to break down organophosphorous nerve agents by inducing "natural selection" of enzymes in a test tube to produce effective remedies.  

Current nerve gas drugs are somewhat effective but they do not protect against high-dose exposure or against all nerve agents and they may cause several major side effects. These drugs also cannot prevent or repair motor and cerebral nerve damage caused by the agent, reports.

Nerve gases, produced by armies and terrorist organizations around the world, can cause damage to nerves and muscles by disrupting chemical messages. If untreated, these compounds will cause death by suffocation.

Since nerve gases are man made, the issue in creating an enzyme to break the gas down is that evolution has not developed natural enzymes to carry out this task, according to Professor Dan Tawfik's chemistry department at the Weizmann Institute took this into their own hands by tailoring enzymes using evolution in a test tube to mutate the enzymes through many generations.

The team selected the PON1 enzyme - typically used in the human body to oxidize fats accumulated on blood vessel walls - because it naturally performs some degradation of nerve agent compounds. After performing the artificial evolution on the enzyme, it has become faster and more effective at breaking down nerve gases.

When these gases were given to animals as a preventative treatment before exposure, they gave almost complete protection against two types of nerve agents, even when exposed to relatively high levels, reports. The scientists hope to continue to test this process on enzymes until they develop enzymes effective enough to be injected immediately after exposure.