To correct the problem, researchers transplanted a copy of the missing gene into the child's body in order to trigger production of the crucial enzyme.

Researchers hope that the new blood cells will pump out normal levels of the crucial enzyme and restore the girl's immune system to full health.

OTC is an enzyme crucial to removing nitrogen, a by-product of protein breakdown, from the body.

Plants are unable to read this "antisense RNA" and, therefore, could not make the crucial enzyme, the researchers said.

The crucial enzyme required in the stimulation of the downstream pathway is caspase-1, which is located inside the cells.

The myxopyronin binds to and inhibits the crucial bacterial enzyme, RNA polymerase.

Stressors can cause a change in the activity of crucial enzymes inside an organisms body.

The children all suffer from severe combined immunodeficiency, or SCID, which is caused by the absence an enzyme crucial to maintaining the body's immune system.

Scientists will also look for drugs that block crucial enzymes the virus uses for replication, like proteases.

A principal reason, according to the patent, is that the body fights back with antibodies that block the action of a crucial enzyme, called reverse transcripterase.