Jun'ichi Mano1,2, Asami Ishibashi3, Hitoshi Muneuchi3, Chihiro Morita4, Hiroki Sakai4, Md Sanaullah Biswas5,6, Takao Koeduka7, Sakihito Kitajima8,9. 1. Science Research Center, Organization for Research Initiatives, Yamaguchi University, Yoshida 1677-1, Yamaguchi, 753-8515, Japan. mano@yamaguchi-u.ac.jp. 2. Graduate School of Sciences and Technology for Innovation, Yamaguchi University, Yoshida 1677-1, Yamaguchi, 753-8515, Japan. mano@yamaguchi-u.ac.jp. 3. Graduate School of Agriculture, Yamaguchi University, Yoshida 1677-1, Yamaguchi, 753-8515, Japan. 4. Faculty of Agriculture, Yamaguchi University, Yoshida 1677-1, Yamaguchi, 753-8515, Japan. 5. The United Graduate School of Agriculture, Tottori University, Koyama-Cho Minami 4-101, Tottori, 680-8550, Japan. 6. Department of Horticulture, Bangabandhu Sheikh Mujibur Rahman Agricultural University, Gazipur, 1706, Bangladesh. 7. Graduate School of Sciences and Technology for Innovation, Yamaguchi University, Yoshida 1677-1, Yamaguchi, 753-8515, Japan. 8. Department of Applied Biology, Kyoto Institute of Technology, Matsugasaki Sakyo-ku, Kyoto, 606-8585, Japan. 9. The Center for Advanced Insect Research Promotion, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto, 606-8585, Japan.
Abstract
MAIN CONCLUSION: Acrolein is a lipid-derived highly reactive aldehyde, mediating oxidative signal and damage in plants. We found acrolein-scavenging glutathione transferase activity in plants and purified a low K M isozyme from spinach. Various environmental stressors on plants cause the generation of acrolein, a highly toxic aldehyde produced from lipid peroxides, via the promotion of the formation of reactive oxygen species, which oxidize membrane lipids. In mammals, acrolein is scavenged by glutathione transferase (GST; EC 2.5.1.18) isozymes of Alpha, Pi, and Mu classes, but plants lack these GST classes. We detected the acrolein-scavenging GST activity in four species of plants, and purified an isozyme showing this activity from spinach (Spinacia oleracea L.) leaves. The isozyme (GST-Acr), obtained after an affinity chromatography and two ion exchange chromatography steps, showed the K M value for acrolein 93 μM, the smallest value known for acrolein-detoxifying enzymes in plants. Peptide sequence homology search revealed that GST-Acr belongs to the GST Tau, a plant-specific class. The Arabidopsis thaliana GST Tau19, which has the closest sequence similar to spinach GST-Acr, also showed a high catalytic efficiency for acrolein. These results suggest that GST plays as a scavenger for acrolein in plants.
MAIN CONCLUSION: Acrolein is a lipid-derived highly reactive aldehyde, mediating oxidative signal and damage in plants. We found acrolein-scavenging glutathione transferase activity in plants and purified a low K M isozyme from spinach. Various environmental stressors on plants cause the generation of acrolein, a highly toxic aldehyde produced from lipid peroxides, via the promotion of the formation of reactive oxygen species, which oxidize membrane lipids. In mammals, acrolein is scavenged by glutathione transferase (GST; EC 2.5.1.18) isozymes of Alpha, Pi, and Mu classes, but plants lack these GST classes. We detected the acrolein-scavenging GST activity in four species of plants, and purified an isozyme showing this activity from spinach (Spinacia oleracea L.) leaves. The isozyme (GST-Acr), obtained after an affinity chromatography and two ion exchange chromatography steps, showed the K M value for acrolein 93 μM, the smallest value known for acrolein-detoxifying enzymes in plants. Peptide sequence homology search revealed that GST-Acr belongs to the GST Tau, a plant-specific class. The Arabidopsis thaliana GST Tau19, which has the closest sequence similar to spinach GST-Acr, also showed a high catalytic efficiency for acrolein. These results suggest that GST plays as a scavenger for acrolein in plants.
Authors: Stephen F Altschul; John C Wootton; E Michael Gertz; Richa Agarwala; Aleksandr Morgulis; Alejandro A Schäffer; Yi-Kuo Yu Journal: FEBS J Date: 2005-10 Impact factor: 5.542