Biochemical Mechanisms for the Maintenance of Oxidative Stress Under Control in Plants

D.G. ARIAS; C.V. PIATTONI; S.A. GUERRERO; A.A. IGLESIAS

Handbook of Plant and Crop Stress, 3rd ed

CRC Press Taylor & Francis Group

Lugar: Boca Raton; Año: 2011; p. 157 - 190

It is believed that over 2.2 billion years ago, the presence of O2 in the Earth’s atmosphere was originated due to the evolution of cyanobacteria photosynthetic activity, which used the sun’s energy and water to produce sugars with the release of O2. Since then, several organisms began to evolve an antioxidant defense that gives them the capacity to tolerate O2 and use it for metabolic transformation and biosynthesis. Considering the relationship between aerobic organisms and O2, it is remarkable that this molecule can be both beneficial and damaging. Beneficial for the reason that O2 is essential as electron exchanger for an efficient respiration and photosynthetic activity and it is largely used for signal transduction; while damaging because O2 can cause dysfunction on cell components by irreversible modifications on DNA, proteins, sugars, and lipids. Hence, there is a balance/imbalance between both sides, which is critical for the cell functionality and survival.