|Stipanovic, Robert - Bob|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 6/26/2005
Publication Date: 10/3/2005
Citation: Akhunov, A.A., Golubenko, Z., Abdurashidova, N.A., Ibragimov, F.A., Beresneva, Y.V., Khashimova, N.R., Mustakimova, E.C., Akbarova, G.O., Bokov, A.F., Stipanovic, R.D. 2005. Role of peroxidase in resistance of Malvaceae to Verticillium dahliae [abstract]. Proceedings of the 6th International Symposium on the Chemistry of Natural Compounds. p. 154.
Technical Abstract: Peroxidases participate in many reactions and regulate multiple processes in the plant, with anion peroxidases playing a key role in these processes. These enzymes could serve as markers to identify resistant plants. On this basis, a new test for resistance to fungal pathogens using peroxidase activity and isoenzyme formation will be developed. Initially we investigated two representatives in the family Malvaceae. Upon infection with Verticillium dahliae, the plant’s peroxidase activity increase sharply in comparison to control mock inoculated plants. We also observed the occurrence of additional isoforms in infected plants. Isoelectrofocusing shows the activation of an acid isoform which participates in lignification and suberinization when phytopathogens are introduced. A new isoform was observed in the first hour after inoculation. Plant proteins which have an affinity for chitin are known and create a barrier to pathogen penetration. Therefore, we have further investigated chitin - specific isoforms of peroxidase from Malvaceae species. For this purpose we used column chromatography on chitin. An increase in synthesis and of chitin specific isoforms activity in resistant species of Malvaceae was observed one hour after inoculation. These data confirm the activation of some peroxidase in the presence of chitin. Our data support other observations concerning activation of peroxidase isoform that bind chitin. The chitin specific fraction was investigated by isoelectrofocusing and capillary electrophoresis. Two isoforms with Rf 0.36 and 0.40 which are in area p1 3.5 bind with chitin. On the basis of our data, we conclude that a rapid activation of chitin-specific peroxidase isoforms in stems of Malva sylvestris is activated by the pathogen Verticillium dahliae.