1021-4437/05/5202- © 2005
Russian Journal of Plant Physiology, Vol. 52, No. 2, 2005, pp. 209–212. Translated from Fiziologiya Rastenii, Vol. 52, No. 2, 2005, pp. 238–242.
Original Russian Text Copyright © 2005 by Yusupova, Akhmetova, Khairullin, Maksimov.
The set of physiologically active substances
involved in the control of plant growth and develop-
ment and in their defensive responses is rather wide and
diverse. Among them are auxins, cytokinins, gibberel-
lins, brassinosteroids, ABA, ethylene , salicylic and
jasmonic acids, various phenolic compounds, some
fatty acids, oligogalacturinides, and cell-wall compo-
nents of plants, fungi, and bacteria [2–4]. The mecha-
nisms of their biological activity are complex and
diverse. For example, some of them can trigger defen-
sive responses by the enhancement of phytoalexin syn-
thesis, induction of defensive proteins, or acceleration
of lignin synthesis [4, 5]. The regulatory effects of oli-
gosaccharins on cell morphogenesis and elongation
were demonstrated [6, 7]. Therefore, oligosaccharins
are used in agriculture to control plant tolerance and
One of the ways for the induction of plant defensive
responses by chitin, chitosan, and chitooligosaccha-
rides (ChOS) may be their inﬂuence on H
tion and peroxidase activity [9, 10]. Earlier we have
observed that wheat anionic peroxidases with pI of
could be absorbed by chitin . ChOS-induced activa-
tion of wheat peroxidase was also demonstrated .
However, we do not know much about their effects on
particular peroxidase isoforms and ROS generation.
In this connection, we studied the effects of ChOS
generation and the activities of anionic perox-
idases in the wheat coleoptile segments.
MATERIALS AND METHODS
ChOS preparation with a mol wt of 5–10 kD and the
acetylation level of 65% was produced from crab chitin
(Fluka, Switzerland) according to the method sug-
gested by Maksimov and Smirnova .
Auxin-like and inhibitory activities of ChOS were
studied on wheat (cv. Simbirka) coleoptile segments in
a test-system developed by Kefeli
. The seg-
ments were incubated in the medium containing 0.01–
100 mg/l ChOS and 10 mg/l IAA for 3 and 6 h. Control
segments were kept on distilled water. No less than
20 segments were used in each treatment.
The content of hydrogen peroxide in the incubation
medium was measured from the chemoluminescence of
oxidized by H
in the reaction catalyzed by peroxi-
dase, using a KhLM-0.03 apparatus (Russia). The
apparatus and procedure have been described by us in
detail in . The calibration curve was built up using
M). Puriﬁed H
(Reakhim, Russia) was kindly provided by Prof.
V.V. Shereshovets (Institute of Organic Chemistry,
Peroxidase activity was assayed in the protein
extracted from wheat coleoptiles after their homogeni-
The Effect of Chitooligosaccharides
on Hydrogen Peroxide Production and Anionic Peroxidase
Activity in Wheat Coleoptiles
Z. R. Yusupova, I. E. Akhmetova, R. M. Khairullin, and I. V. Maksimov
Institute Biochemistry and Genetics, Ufa Research Center, Russian Academy of Sciences,
pr. Oktyabrya 69, Ufa, Bashkortostan, 450054 Russia;
Received August 26, 2004
—We studied the effects of chitooligosaccharides (ChOS) with a mol wt of 5 kD, the degree of acety-
lation of 65%, and the concentrations from 0.01 to 100 mg/l on the content of hydrogen peroxide in incubation
medium and the activity of anionic peroxidase (pI
) in the segments of wheat (
production and peroxidase activity were found to be dependent on the ChOS concentration. After 3
h of incubation, the highest H
level in medium was observed at 0.01 mg/l ChOS, whereas after 6h, at 1 mg/l.
After 3 h of incubation, ChOS suppressed peroxidase activity. After 6 h of incubation, high ChOS concentra-
tions enhanced peroxidase activity. IAA favored H
accumulation in medium and suppressed anionic perox-
idase. The involvement of ChOS in the control of the level of reactive oxygen species and anionic peroxidase
activity in plant cells is suggested.
Key words: Triticum aestivum - chitooligosaccharides - IAA - hydrogen peroxide - peroxidase - isoforms
: ChOS—chitooligosaccharides; PB—phosphate
buffer; ROS—reactive oxygen species.