Toxin



A toxin is a poisonous substance produced within living cells or organisms. The term was first employed by the organic chemist Ludwig Brieger (Born::1849-Died::1919). There is a distinction between the terms toxicant and toxin: a toxicant is any chemical that can be of natural or synthetic origin, capable of causing a deleterious effect on a living organism. On the other hand, a toxin is a toxicant which is produced exclusively by a living organism, floral or faunal, including bacteria.

Occurrence in nature
There are several examples of organisms that produce toxins in nature. Many of these cause disease in humans and other organisms. Several species of bacteria produce toxins such as corynebacterium diphtheriae (causes diphtheria), vibrio cholerae (causes cholera), Clostridium tetani (causes Tetanus), clostridium botulinum (causes Botulism) and so on. Some plants, fungi, or sponges produce toxins in self-defense protecting them from being eaten since they can not move in flight.