The Dynamics of Contents of the Total Protein, Haemocyanin and Activity of the Antioxidant Enzymes Under Condition of Acute Hyperthermia in Pulmonate Mollusk Lymnaea stagnalis

The dynamics of total protein’s and hemocyanin’s content in the hemolymph, as well as the activity of the antioxidant enzymes (peroxidase, catalase and glutathione S-transferase) in pulmonate mollusc Lymnaea stagnalis (Linnaeus, 1758) under the impact of acute temperature stress were evaluated. It has been shown that the effect of acute thermal stress (30 °C) leads to activation of physiological mechanisms of stress resistance and has no influence on activity of the antioxidant enzymes in investigated population of molluscs

Secondary Metabolites Detected in Deep-Water Endemic Amphipods of Lake Baikal: Bacterial or Crustacean Origin?

The aim of the study was to conduct a dereplication analysis of crude extract of deepwater Baikal’s endemic amphipod species, Ommatogammarus albinus. Detected masses provide some evidence that amphipod’s extract might contain both host and microbiota secondary metabolites. Some of the masses correspond with known structures isolated from eubacteria. Also, two compounds did not match with any registered natural products from the database Dictionary of Natural Products. Those findings allow suggesting that Baikal’s endemics and their microbiota are promising sources of novel natural products

Haemolymph of Cold-Adapted Baikal Endemic Amphipods as a Promising Source for Screening of Novel Natural Products

The aim of this study was to assess the possibility to use Baikal endemic amphipods as a source for screening of novel natural products. Analysis of amphipod’s E. verrucosus hemolymph by HPLC-MS was performed for the first time. A number of natural products with new molecular mass for Baikal endemic macroinvertebrates were found. We found a compound as chrysin by comparison of MS1, MS2 profiles and molecular mass of natural products registered in Dictionary of Natural Products and MZ-cloud databases. Also, we found new compound with mass 493.80277 Da, circulating in the amphipod’s hemolymph

The Estimation of the Antioxidant Enzymes Activity in Representatives of Different Populations of Lymnaea stagnalis Differ in the Degree of Infestation Under Temperature Stress

The aim of this study was to assess the impact of effects of thermal stress and parasitic infestation on the activity of antioxidant enzymes (peroxidase, catalase and glutathione S-transferase) in different populations of wide-spread species of pulmonate mollusk Lymnaea stagnalis from water bodies with different levels of anthropogenic pollution in Belarus - unpolluted Narach Lake and polluted Chizhovsky reservoir. There are several differences were found under thermal stress exposition (35 °С). In non infected mollusсs of both populations the peroxidase activity decreased and activity of catalase increased. An activity of glutathione S-transferase increased in non infested mollusks that inhabit polluted Chizhovsky reservoir

Estimation of experimental cohabitation between Holarctic and Baikal Endemic Amphipods Species: G. lacustris against G. fasciatus

The aim of the present study was to estimate the cohabitation effect of two invasive amphipods species (Gammarus lacustris and Gmelinoides fasciatus) by the cellular stress markers such as activity of antioxidant enzymes (peroxidase, catalase, glutathione S-transferase) and content of heat shock protein 70 (HSP70). Changes of antioxidant enzymes activity were shown in both amphipods species. It was observed that in G. lacustris cohabitation with other species led to the activation of all studied enzymes, whereas in G. fasciatus only peroxidase activity alteration was recorded. Notably, the activation of all studied enzymes was short-term. There were no changes of HSP70 content for both species. According to obtained data less sensitivity of G. fasciatus stress markers can be one of the key advantages for further successful distribution and adaptation to the new conditions

The Particularities of Nonspecific Stress Resistance Mechanism Activation in Baikalian Endemic Amphipod Gmelinoides fasciatus (Stebb, 1899) under Thermal Stress

The aim of the current study was to determine the characteristics of the stress response in endemic species Gmelinoides fasciatus (Stebb., 1899) in comparison with other Baikal amphipods under short term thermal stress. It were shown the changes in activity of antioxidant enzymes, and lactate dehydrogenase correlated with content of lactate under the influence of gradual temperature increase. While the changes of cellular stress - markers content or their activity in other Baikal species occurred beyond the thermal preference zone, the cellular stress - markers content or their activity in G. fasciatus associated with entrance into the thermal preference zone. Thus we concluded that the relict endemic species G. fasciatus has a different stress resistance mechanism to elevated temperature than other Baikal amphipods species

A Comparative Study of Antioxidant Enzymes Activity to Heat Shock in Amphipods Gmelinoides fasciatus of Littoral Community of Lake Baikal and Thermal Springs

The aim of the current study was to comparative assessment of the antioxidant enzymes activity (peroxidase, catalase, glutathione S-transferase) in endemic species Gmelinoides fasciatus (Stebbing, 1899) inhabitants of the littoral community of the Lake Baikal and the thermal spring under short term thermal stress. It was shown, that the exposure of G. fasciatus from different areas to acute temperature stress didn’t lead to changes in the activities of three key enzymes of the antioxidant system. However, it was found that the activity of glutathione S-transferase in the control animals of thermal springs population is higher than in animals of Lake Baikal. This can be determined by peculiarities of environment of different populations

The Influence of Trematode Invasion on the Thermoresistance of Lymnaea stagnalis (Gastropoda, Pulmonata) Population from the Floodplain Reservoir of Angara River

The average terms (AT) of survival at 35°C in matured Lymnaea stagnalis with different levels of trematode invasion have been determined. There were noninvaded individuals from a natural population of L. stagnalis and laboratory culture; poorly (rear sporocysts and rediae) and heavily invaded (numerous cercariae) ones from a natural population. The AT values for both noninvaded groups were practically identical (31.6 and 32.4 hours, respectively). The AT values for the heavily invaded ones (18.0 hours) were significantly lower (p < 0.01) than for all of groups which mentioned above. The AT value for the non-selected sample from a natural population (22.5 hours) was rather low because of their strong infestation of mollusks (up to 84.6%) with cercaria. Obviously, the thermoresistance of natural L. stagnalis populations is largely determined both by the shares of invaded mollusks and the stages of trematode life cycle in them

Culturable Actinobacteria Associated with Baikal Algae: Diversity and Antimicrobial Activity

The aim of the study was to assess the biodiversity of culturable strains of actinobacteria isolated from freshwater Baikal algae Draparnaldioides baicalensis and to assess the antimicrobial activity of compounds against Gram-positive bacteria. In the course of this study, we isolated both widespread strains of the genus Streptomyces, and rare representatives of the genus Saccharopolyspora, Nonomuraea, Rhodococcus and Micromonospora. We demonstrated that the strains produce natural products with antimicrobial activity. Considering the large number of rare and active strains associated with the endemic algae D. baicalensis, we shown that these microorganisms have a value for biomedical and biotechnological development and to discovery of new natural compounds, including antibiotics