IN INOCULANTS Nodulaid - 17th International Nitrogen Fixation ...

17 th International Congress on Nitrogen Fixation
Fremantle, Western Australia
27 November – 1 December 2011
Session Details: Tuesday 29 November 2011
Authors:
Concurrent Session 4 – Applications of New Technologies
1100 - 1230
Tikhonovich I.A. 1,2 , Dolgikh E.A. 1 , Leppyanen I.V. 1 , Lopatin S.А. 3 , Varlamov V.P. 3
1 All-Russia Research Institute for Agricultural Microbiology (ARRIAM), chausse
Podbelskogo 3, Pushkin 8, Saint-Petersburg, 196608, Russia; 2 Saint Petersburg State
University (SPbSU), Universitetskaya nab., 7-9, St. Petersburg, 199034, Russia;
3 Center Bioengineering RAS, street of 60 th of October, 7/1, Moscow, 117312.
Presentation Title: New application of N2-fixing organisms: heterologous expression of rhizobial
glycosylatransferases involved in chitin oligosaccharides synthesis
Presentation Time: 1200 - 1220
Due to their unique properties like biocompatibility, low toxicity and simplicity of biodegradation, the chitin
oligosaccharides (COs, chitin oligomers, chitosane oligomers and their derivatives) find a wide application. There
is significant interest in application of COs in agriculture. Chitin oligosaccharides produced by pathogenic fungi,
are effectively detected by many plant species as elicitors leading to defence reactions and inactivation or
destruction of the potential pathogen. In plants COs activate a set of defence reactions such as activation of
defence enzymes, production of active oxygen species (О2 - , Н2О2, OH - ), biosynthesis of phytoalexins and callose
or lignin deposition. Therefore application of these compounds and their modified analogs for stimulation of plant
resistance against pathogens looks like enough promising. The treatment of plants with COs is more preferential
in comparison with chemical agents because they are not toxic and easily utilized. That is a reason why last
years the interest in the synthesis of COs by enzymatic methods using either the biosynthetic
glycosyltransferases or glycosidases is being increased. The possibility of enzymatic synthesis of chitin
oligomeres by means of unique enzymes of soil bacteria rhizobia has been investigated in our experiments.
Original approaches to analyse the structure of synthesized chitin oligosaccharides by methods of high
performance liquid chromatography and mass-spectrometry have been developed. In our experiments the elicitor
activity of synthesized chitin oligomers has been analysed using specific tests.
This research was supported by the Ministry of Education and Science of the Russian Federation (state
contracts ## 16.512.11.2183, 16.552.11.7047).
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