Evaluation of biochemical responses in Palearctic and Lake Baikal endemic amphipod species exposed t

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Evaluation of biochemical responses in Palearctic
and Lake Baikal endemic amphipod species exposed
to toxicity stress
REG-4 Structural and evolutionary study of
ecosystems of water bodies in the Baikal region

• Marina Protopopova,
• Darya Bedulina
• Irkutsk State University, Irkutsk
• Laboratory of biological systems adaptation

Bolshie Koty, Baikal, Russia June 25-29, 2007
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The evaluation of antioxidant enzymes and sHSP as
possible biomarkers for using in the
toxicological studies of Baikal endemic species

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The biomarkers of stress

• Antioxidant enzymes
• peroxidase (POD)
• catalase (CAT)
• Heat-shock proteins (HSP)
• small heat-shock proteins (sHSP)

Toxic stress
solution of cadmium chloride (CdCl2)
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The objects of the research
Freshwater species of amphipods (Crustacea,
Amphipoda)
Baikal species
E. cyaneus (Dyb.)
E. verrucosus (Gerstf)

• Palearctic species

Gammarus lacustris (Sars)
Gammarus lacustris Sars
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Methods
Measurement of enzymes activities
Spectrophotometric method
POD activity was measured with guaiacol as the
substrate at 436 nm, pH 5 according to Bergmeyer
(1983)
CAT activity was measured with hydrogen peroxide
as the substrate at 240 nm and a pH of 7
according to Aebi (1984).
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Methods
Measurement of sHSPs content
SDS- electrophoresis
Western-blotting
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Results
POD activities in the three amphipod species
exposed to 0,05 mgL-1CdCl2
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Results
CAT activities in the three amphipod species
exposed to 0,05 mgL-1CdCl2
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Results
Western blot analysis on sHSP of the amphypods
after 24 hours exposition in different CdCl2
solutions
line 1 control, line 2 - 0,05 mgL-1, line 3 -
0,5 mgL-1, line 4 5 mgL-1.

• E. cyaneus,
• E. verrucosus,
• C. G. lacustris

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The chaperon function of sHSP
stress
The refolded protein chain
The native protein chain
The denaturated protein chain
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Conclusion

• CdCl2 causes significant effects of the
  peroxidase.
• CdCl2 causes induction of the dose-dependent
  synthesis of small heat shock proteins.
• All measured parameters varied interspecifically
  and depended on the ability of the species to
  resist cadmium chloride toxicity.

The synthesis of small heat shock proteins and
peroxidase activity, could be successfully used
as biomarkers for the further studies in amphipod
species including endemics from Lake Baikal.
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Laboratory of biological systems adaptation
The grants of Russian Foundation for Basic
Research ? 06-04-48099-?, 05-04-97239-baikal,
05-04-97263-baikal The publication Evaluation
of biochemical responses in Palearctic and Lake
Baikal' endemic amphipod species exposed to CdCl2
// Ecotoxicology and Environmental Safety, 2007
(in press)
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Thank you