| Autor: |
Murielle Eyletters, Yao Casimir Brou, Robert Lannoye |
| Rok vydání: |
1998 |
| Předmět: |
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| Zdroj: |
Photosynthesis: Mechanisms and Effects ISBN: 9780792355472 |
| DOI: |
10.1007/978-94-011-3953-3_467 |
| Popis: |
The most feared and the most widespread plant stress agents are active oxygen species. One regroups under the term « active oxygen species» all molecules derived of oxygen that possess a more or less great reactivity and aggressiveness towards membrane structures (lipids and proteins) and nuclear structures of plant or animal cell [1, 2]. Among these species are superoxide radicals (O2 -) and hydrogen peroxide (H2O2). Hydrogen peroxide is produced in peroxisomes during glycolate pathway and during enzymatic dismutation of superoxide radicals [1]. These reduced oxygen species are not only generated as by-products of endogenous biological reactions, but also their formation increases during biotic and non-biotic stress. Accumulation of superoxide radicals is prevented by superoxide dismutase (EC 1.15.1.1) which catalyses the dismutation of O2 - to O2 and H2O2 [3]. The three known types of this enzyme are distinguishable by their metal prosthetic part made of manganese (MnSOD), iron (FeSOD) or copper and zinc (Cu/ZnSOD), and by their behaviour towards specific inhibitors [2]. H2O2 is scavenged by catalases in the peroxisomes and by ascorbate peroxidase in Halliwell-Asada cycle [1, 4]. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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