1. Effect of copper stress on polyamine and reactive oxygen species metabolism in aseptic seedlings of Potamogeton crispus L
- Author
-
Qiao Xuqiang, Shi Guoxin, Tian Xiuli, Jiang Yan, Chen Lin, and Wang Penghe
- Subjects
biology ,Spermine ,Aquatic Science ,Pollution ,Ornithine decarboxylase ,Spermidine ,Superoxide dismutase ,chemistry.chemical_compound ,chemistry ,Biochemistry ,Catalase ,Earth and Planetary Sciences (miscellaneous) ,Putrescine ,biology.protein ,Diamine oxidase ,Polyamine ,Water Science and Technology - Abstract
Taking aseptic seedlings of P.crispus as the experimental material,the effect of different concentrations of Cu2+(0,1,2,4,8,12 μmol/L) on the metabolism of polyamine(PAs) and reactive oxygen were investigated.With the increasing of Cu2+ concentration,the results indicated that:(1) Superoxide dismutase(SOD) activity increased markedly,while the activities of peroxidase(POD) and catalase(CAT) increased progressively followed by a decline.(2) The generation rate of O·-2and the content of H2O2 and MDA increased,while soluble protein content decreased.(3) Free putrescine(Put) content first enhanced and then reduced notably.However,the content of free spermidine(Spd) decreased gradually and spermine(Spm) increased significantly.Therefore,the ratio of free(Spd+Spm)/Put promptly increased under high concentrations of Cu2+ stress.The changes of total PAs content were similar to those on free PAs.Perchloric acid soluble conjugated(PS-conjugated) Put and Spm changed in the same pattern as free PAs.While PS-conjugated Spd content increased slightly.In addition,the content of perchloric acid insoluble bound(PIS-bound) Put and Spd first increased and then decreased,but they were still higher than those in the control.Moreover,PIS-bound Spm content declined.(4) With the increase of Cu2+ concentration,the activity of arginine decarboxylase(ADC) sharply decreased after a transient increase,while the activity of ornithine decarboxylase(ODC) did not change significantly.Polyamine oxidase(PAO) and diamine oxidase(DAO) activities increased gradually,followed by a decrease.Our results suggested that Cu2+ stress induced obvious oxidative damage on aseptic seedlings of P.crispus.The up-regulation of antioxidant enzymes activities and Spm content,the changes of Put into Spd and Spm as well as the conversion between different forms of polyamines played a key role in the adaptation mechanism of aseptic seedlings of P.crispus under Cu2+ stress.
- Published
- 2013