text: Enzyme inhibitors are found in nature and also produced artificially in the laboratory. Naturally occurring enzyme inhibitors regulate many metabolic processes and are essential for life. In addition, naturally produced poisons are often enzyme inhibitors that have evolved for use as toxic agents against predators, prey, and competing organisms. These natural toxins include some of the most poisonous substances known. Artificial inhibitors are often used as drugs, but can also be insecticides such as malathion, herbicides such as glyphosate, or disinfectants such as triclosan. Other artificial enzyme inhibitors block acetylcholinesterase, an enzyme which breaks down acetylcholine, and are used as nerve agents in chemical warfare.