Acrolein-detoxifying isozymes of glutathione transferase in plants

作者：Mano Jun'ichi^*; Ishibashi Asami; Muneuchi Hitoshi; Morita Chihiro; Sakai Hiroki; Biswas Md Sanaullah; Koeduka Takao; Kitajima Sakihito

来源：Planta, 2017, 245(2): 255-264.

DOI：10.1007/s00425-016-2604-5

• Acrolein
• Oxidative stress
• Oxylipin carbonyls
• Reactive carbonyl species
• Reactive electrophiles

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 mu M, 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.

• 出版日期2017-2