PT - JOURNAL ARTICLE AU - Chen, Z AU - Silva, H AU - Klessig, DF TI - Active oxygen species in the induction of plant systemic acquired resistance by salicylic acid AID - 10.1126/science.8266079 DP - 1993 Dec 17 TA - Science PG - 1883--1886 VI - 262 IP - 5141 4099 - http://science.sciencemag.org/content/262/5141/1883.short 4100 - http://science.sciencemag.org/content/262/5141/1883.full SO - Science1993 Dec 17; 262 AB - A complementary DNA encoding a salicylic acid (SA)-binding protein has been cloned. Its properties suggest involvement in SA-mediated induction of systemic acquired resistance (SAR) in plants. The sequence of the protein is similar to that of catalases and the protein exhibits catalase activity. Salicylic acid specifically inhibited the catalase activity in vitro and induced an increase in H2O2 concentrations in vivo. H2O2 or compounds, such as SA, that inhibit catalases or enhance the generation of H2O2, induced expression of defense-related genes associated with SAR. Thus, the action of SA in SAR is likely mediated by elevated amounts of H2O2.