ARS | Publication request: PARTICIPATION OF CHITIN SPECIFIC ISOFORMS OF PEROXIDASE IN PROTECTIVE REACTION OF PLANTS INFECTED BY PATHOGENS

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: August 1, 2005
Publication Date: October 30, 2005
Citation: Akhunov, A.A., Golubenko, Z., Beresneva, Y.V., Khashimova, N.A., Ibragimov, F.A., Abdurashidova, N.A., Mustakimova, E.C., Stipanovic, R.D. 2005. Participation of chitin specific isoforms of peroxidase in protective reaction of plants infected by pathogens [abstract]. Proceedings of the 3rd Moscow International Congress on Biotechnology: State of the Art and Prospects of Development. p. 225.

Technical Abstract: We are interested in how isoforms of peroxidases may influence the cotton plant's resistance to pathogens. Cotton is a member of the Malvaceae and we have been investigating the resistance of wild members of the Malvaceae to the plant pathogen Verticillium dahliae. Using electrophoresis, we have observed four isoforms of peroxidase in tissue from Althea rosa infected with V. dahliae. These isoforms had Rf values of 0.32, 0.35, 0.56, and 0.59. We submitted these to chromatography on a chitin column. Two isoforms with Rf equal to 0.56 and 0.59 were retained by the column. These isoforms have a pI value of approximately 8.3. A densitogram derived from electrophoresis showed an increase in the peroxidase activity of chitin specific isoforms in A. rosa after inoculation with the pathogen. In a similar experiment with Malva bucharica, electrophoresis showed five isoform peroxidases with Rf 0.33, 0.37, 0.41, 0.44, and 0.48. Chromatography of extracts from M. bucharica on a chitin column showed peroxidases with Rf 0.33, 0.37; and with pi 9.7, 10.0, respectively, were bound by the chitin column. Peroxidases that did not bind to chitin also increased. Our data indicate that chitin-specific isoforms of peroxidase play an important role in protecting plants against microbial attack. This data indicates that an increase in peroxidase activity in A. rosa correlates with resistance to V. dahliae and M. bucharica and lower activity correlates with susceptibility.