1021-4437/00/4706- $25.00 © 2000
Russian Journal of Plant Physiology, Vol. 47, No. 6, 2000, pp. 721–727. Translated from Fiziologiya Rastenii, Vol. 47, No. 6, 2000, pp. 821–828.
Original Russian Text Copyright © 2000 by Troitskaya, Zhiznevskaya, Ismailov.
Depending on which major nitrogen compound of
symbiotically ﬁxed dinitrogen is exported from root
nodules, legume plants belong to the ureide or amide
type of nitrogen metabolism. In the temperate species,
, etc., asparagine is the
major nitrogen compound exported from the nodules.
In the tropical species from the tribe Phaseoleae, such
, 70–90% of symbiot-
ically ﬁxed nitrogen is transported into the shoots as the
ureides allantoin and allantoic acid [1, 2].
Allantoin synthesis from uric acid is catalyzed by
uricase (EC 18.104.22.168) in peroxisomes and is accom-
panied by the evolution of hydrogen peroxide,
which is immediately degraded by peroxisomal cat-
alase (EC 22.214.171.124) [1, 3]. In the nodules of amide-
transporting species, catalase is neither directly nor
indirectly related to the synthesis of the transported
forms of symbiotically ﬁxed dinitrogen [1, 2].
The previous study of iron-containing proteins from
legume nodules  found considerably higher catalase
activity in the nodules of soybeans, a ureide plant spe-
cies, than in the nodules of the amide plant species,
lupine and broad beans. The catalase activity in soy-
bean nodules was shown to exceed that of pea nodules
. Meanwhile, in the nodules of white lupine, an
amide plant species, the electron cytochemical study
demonstrated that high catalase activity in peroxisomes
considerably decreased when dinitrogen ﬁxation was
inhibited with nitrate.
Using the data from the
 suggested that catalase participated in protect-
ing Lb, an essential component of the symbiotic dini-
trogen ﬁxation, from irreversible oxidation by hydro-
gen peroxide. At the same time, Dalton
sumed that Lb was protected by another H
detoxifying enzyme, ascorbate peroxidase.
In this study, we investigated the probable catalase
participation in the functioning of the symbiotic sys-
tems of dinitrogen ﬁxation in the amide-transporting
legumes. To do this, we compared catalase activities in
the nodules and the roots of several ureide- and amide-
transporting plant species. In addition, the catalase dis-
tribution in nodule tissues was related to Lb content and
the efﬁciency of the symbiotic dinitrogen ﬁxation.
MATERIALS AND METHODS
The following species represented the amide-trans-
porting plants: alfalfa (
L., cv. Sever-
naya gibridnaya), garden pea (
L., cv. Svo-
boda), red clover (
L., cv. VIK-7),
bird’s foot (
Broth., cv. Neris), broad
L., cv. Aushra), yellow lupine (
L., cv. Fakel), chick pea (
cv. Yubileynyi), and goat’s rue (
wildly-growing species recently introduced to cultiva-
tion. Kidney bean (
L., cv. Saksa),
Catalase Activity of Nodules in the Ureide-
and Amide-transporting Legume Plants
G. N. Troitskaya, G. Ya. Zhiznevskaya, and S. F. Ismailov
Timiryazev Institute of Plant Physiology, Russian Academy of Sciences, Botanicheskaya ul. 35, Moscow, 127276 Russia;
fax: 7 (095) 977-8018; e-mail: firstname.lastname@example.org
Received April 6, 1999
—The relations of catalase activity to the efﬁciency of symbiotic dinitrogen ﬁxation and leghemoglo-
bin (Lb) content were investigated in roots and nodules of several legume plant species together with the cata-
lase distribution between the inner bacteroidal and the outer cortical nodule tissues. The catalase activity in the
nodules exceeded that of the roots of the amide- and ureide-synthesizing plant species by one and two orders
of magnitude. During the growth period, catalase activity and Lb content changed in parallel and reached their
highest levels early in the stage of ﬂowering or fruit formation, depending on plant species. In the case of effec-
tive symbiosis, catalase activity in the nodules was 2.5–5 times higher than in the case of ineffective symbiosis.
Catalase activity in the bacteroidal zone of the nodules was several times higher than that of the cortical tissue,
and two nodule tissues differed in catalase activity more notably in the plant species exporting ureides. The
authors suggest that high catalase activity in the nodules, especially in their bacteroidal zone, is essential for the
efﬁcient functioning of the symbiotic system of dinitrogen ﬁxation in both ureide- and amide-transporting plants.
Key words: Leguminosae - symbiotic nitrogen ﬁxation - effective and ineffective symbiosis - root nodules - cat-