Proteinaceous Plant Toxins with Antimicrobial and Antitumor Activities

Abstract

Plants have a huge variety of bioactive compounds, which confer upon these organisms great potential for defense. Among these compounds there are pro- teins and peptides that are responsible for important roles as the first line of defense against pathogenic microorganisms, such as Gram-positive and Gram- negative bacteria, fungi, and viruses. They also demonstrate antitumor and DNA cleavage activities.Asignificant number of these molecules have been described to show cytotoxic activity against mammalians, inducing mainly neuronal tox- icity and cell death. In view of the latest research in pursuit of possible new drug applications for these protein compounds, this chapter primarily focuses on the antimicrobial and antitumor activities of some plant toxic proteins. The bio- chemical properties are reviewed, in addition to their possible uses in human health as new alternatives to conventional medicines.