Wyniki wyszukiwania - Biblioteka Nauki

1

Bialka jako substrat pokarmowy dla mikroorganizmow wodnych

100%

Kiersztyn B. , Siuda W.

Postępy Mikrobiologii

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2007

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tom 46

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nr 4

355-366

2

Urea in lake ecosystem: the origin, concentration and distribution in relation to trophic state of The Great Mazurian Lakes (Poland)

100%

Siuda W. , Kiersztyn B.

Polish Journal of Ecology

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2015

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tom Vol. 63, nr 1

110--123

EN

The distribution, concentrations and origin of urea were studied in surface and profundal waters of meso-eutrophic and highly eutrophic parts of The Great Mazurian Lake System (GMLS) during spring – autumn period. Urea concentrations varied from 0.25 µM in surface layer to 3.36 µM in profundal zone of studied lakes and were in the range of concentrations noted in other non-polluted freshwater habitats. In the photic zone of lakes of GMLS Urea N made up to 10 % the total DON pool and often exceeded 2-3 times of NH4+-N concentrations. Pattern of changes in urea concentrations observed during three-years study excludes external urea input and suggests supplementation of lake waters with this compounds by phytoplankton decomposition processes. Generally, urea concentrations were negatively correlated with the trophic state index calculated from “algal” as well as from “bacterial” determinants. However, more detailed analysis showed that the relationships between production and assimilation of urea by various plankton components as well as the ecological role of this compound in meso- and eutrophic lakes could be different.

3

Microbial biomass and enzymatic activity of the surface microlayer and subsurface water in two dystrophic lakes

100%

Kostrzewska-Szlakowska I. , Kiersztyn B.

Polish Journal of Microbiology

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2017

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tom 66

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nr 1

EN

Nutrient and organic matter concentration, microbial biomass and activities were studied at the surface microlayers (SML) and subsurface waters (SSW) in two small forest lakes of different water colour. The SML in polyhumic lake is more enriched with dissolved inorganic nitrogen (0.141 mg l⁻¹) than that of oligohumic lake (0.124 mg l⁻¹), the former also contains higher levels of total nitrogen (2.66 mg l⁻¹). Higher activities of lipase (Vmax 2290 nmol l⁻¹1 h⁻¹ in oligo- and 6098 in polyhumic) and glucosidase (Vmax 41 nmol l⁻¹ h⁻¹ in oligo- and 49 in polyhumic) were in the SMLs in both lakes. Phosphatase activity was higher in the oligohumic SML than in SSW (Vmax 632 vs. 339 nmol l⁻¹ h⁻¹)while in polyhumic lake was higher in SSW (Vmax 2258 nmol l⁻¹ h⁻¹ vs. 1908 nmol l⁻¹ h⁻¹). Aminopeptidase activity in the SSW in both lakes was higher than in SMLs (Vmax 2117 in oligo- and 1213 nmol l⁻¹ h⁻¹ in polyhumic). It seems that solar radiation does inhibit neuston microbial community as a whole because secondary production and the share of active bacteria in total bacteria number were higher in SSW. However, in the oligohumic lake the abundance of bacteria in the SML was always higher than in the SSW (4.07 vs. 2.69 × 10⁶ cells ml⁻¹) while in the polyhumic lake was roughly equal (4.48 vs. 4.33 × 10⁶ cells ml⁻¹) in both layers. Results may also suggest that surface communities are not supplemented by immigration from bulk communities. The SML of humic lakes may act as important sinks for allochthonous nutrient resources and may then generate considerable energy pools for microbial food webs.

4

Urea in lake ecosystem: the origin, concentration and distribution in relation to trophic state of The Great Mazurian Lakes (Poland)

100%

Siuda W. , Kiersztyn B.

Polish Journal of Ecology

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2015

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tom 63

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nr 1

EN

The distribution, concentrations and origin of urea were studied in surface and profundal waters of meso-eutrophic and highly eutrophic parts of The Great Mazurian Lake System (GMLS) during spring — autumn period. Urea concentrations varied from 0.25 µM in surface layer to 3.36 µM in profundal zone of studied lakes and were in the range of concentrations noted in other non-polluted freshwater habitats. In the photic zone of lakes of GMLS Urea N made up to 10 % the total DON pool and often exceeded 2-3 times of NH₄-N concentrations. Pattern of changes in urea concentrations observed during three-years study excludes external urea input and suggests supplementation of lake waters with this compounds by phytoplankton decomposition processes. Generally, urea concentrations were negatively correlated with the trophic state index calculated from “algal” as well as from “bacterial” determinants. However, more detailed analysis showed that the relationships between production and assimilation of urea by various plankton components as well as the ecological role of this compound in meso- and eutrophic lakes could be different.

5

Enzymatic fingerprints used for comparison of physiological diversity of microbial communities in clear-water and humic lakes

80%

Siuda W. , Jasser I. , Kiersztyn B.

Polish Journal of Ecology

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2013

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tom Vol. 61, nr 4

715--728

EN

Extracellular enzymes occurring in aquatic environment are heterogeneous in respect to their origin and function, place, where they are located and their activity. They can be divided into mainly ‘bacterial-origin’ enzymes produced by heterotrophic organisms in order to obtain organic carbon, and mostly ‘phytoplankton-bacterial-origin’ enzymes, which are produced by autotrophic and heterotrophic organisms, and are responsible mainly for obtaining inorganic compounds. Enzymes activity provides information about microorganisms present in given environment and about their physiological state. We hypothesize that the patterns (‘fingerprints’) calculated on the basis of activity of several enzymes both mainly ‘bacterial-origin’ and mainly ‘phytoplankton-bacterial-origin’ may be used to characterise lake ecosystems in terms of the physiological structure of aquatic microorganisms present in these lakes. For the study we selected four lakes from Mazurian Lakes District in north-eastern Poland. Three of them were clear-water (lakes: Kuc, Mikołajskie, Tałtowisko) and ranged from oligotrophy to eutrophy, the fourth (Lake Smolak Duży) was slightly acidic (pH 5.2), highly productive and polyhumic. Activity of phosphatase (PA), L-leucine-aminopeptidase (AMP), β-glucosidase (B-Glu), esterase (EST), glucosaminidase (Glu-ami), glucuronidase (Glu-uro) and cellobiohydrolase (Cellob) were measured fluorometrically. The results were normalised and analysis of agglomerative clustering was performed to create an enzyme activity patterns characteristic for lakes. We found out that the enzymatic pattern reflected trophic differences between studied lakes. The patterns (‘fingerprints’) of enzymes were similar for three clear-water lakes, with urease (U–ase), AMP and EST dominating the overall enzymatic activity, but differed substantially for polyhumic lake, in which considerably high PA and saccharolytic enzyme activities were observed. We conclude that the analysis of enzymatic ‘fingerprints’ can be a useful tool to characterise lakes with respect to their trophic status and physiological diversity of microbial assemblages associated with each particular lake.

6

Coomassie blue G250 for visualization of active bacteria from lake environment and culture

80%

Kiersztyn B. , Siuda W. , Chrost R.

Polish Journal of Microbiology

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2017

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tom 66

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nr 3

EN

Bacteria play a fundamental role in the cycling of nutrients in aquatic environments. A precise distinction between active and inactive bacteria is crucial for the description of this process. We have evaluated the usefulness of Coomassie Blue G250 for fluorescent staining of protein containing potentially highly active bacteria. We found that the G250 solution has excitation and emission properties appropriate for direct epifluorescence microscopy observations. It enables fast and effective fluorescent visualization of living, protein-rich bacteria, both in freshwater environment and culture. Our results revealed that the number of G250-stained bacteria from eutrophic lake was positively correlated with other standard bacterial activity markers, like number of bacteria containing 16S rRNA, bacterial secondary productionor maximal potential leucine-aminopeptidase activity. In case of the E. coli culture, the percentage of bacteria visualized with G250 was similar to that of bacteria which accumulated tetracycline. Compared to other common methods utilizing fluorogenic substances forbacteria staining, the approach we evaluated is inexpensive and less hazardous (for example mutagenic) to the environment and researchers. It can be regarded as an additional or alternative method for protein rich, active bacteria staining.

7

Enzymatic "fingerprinting" of physiological diversity of microbial communities in clear-water and humic lakes

80%

Siuda W. , Jasser I. , Kiersztyn B.

Polish Journal of Ecology

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2013

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tom 61

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nr 4

EN

Extracellular enzymes occurring in aquatic environment are heterogeneous in respect to their origin and function, place, where they are located and their activity. They can be divided into mainly ‘bacterial-origin’ enzymes produced by heterotrophic organisms in order to obtain organic carbon, and mostly ‘phytoplankton-bacterial-origin’ enzymes, which are produced by autotrophic and heterotrophic organisms, and are responsible mainly for obtaining inorganic compounds. Enzymes activity provides information about microorganisms present in given environment and about their physiological state. We hypothesize that the patterns (‘fingerprints’) calculated on the basis of activity of several enzymes both mainly ‘bacterial-origin’ and mainly ‘phytoplankton-bacterial-origin’ may be used to characterise lake ecosystems in terms of the physiological structure of aquatic microorganisms present in these lakes. For the study we selected four lakes from Mazurian Lakes District in north-eastern Poland. Three of them were clear-water (lakes: Kuc, Mikołajskie, Tałtowisko) and ranged from oligotrophy to eutrophy, the fourth (Lake Smolak Duży) was slightly acidic (pH 5.2), highly productive and polyhumic. Activity of phosphatase (PA), L-leucine-aminopeptidase (AMP), β-glucosidase (B-Glu), esterase (EST), glucosaminidase (Glu-ami), glucuronidase (Glu-uro) and cellobiohydrolase (Cellob) were measured fluorometrically. The results were normalised and analysis of agglomerative clustering was performed to create an enzyme activity patterns characteristic for lakes. We found out that the enzymatic pattern reflected trophic differences between studied lakes. The patterns (‘fingerprints’) of enzymes were similar for three clear-water lakes, with urease (U–ase), AMP and EST dominating the overall enzymatic activity, but differed substantially for polyhumic lake, in which considerably high PA and saccharolytic enzyme activities were observed. We conclude that the analysis of enzymatic ‘fingerprints’ can be a useful tool to characterise lakes with respect to their trophic status and physiological diversity of microbial assemblages associated with each particular lake.

8

Microbial ectoenzyme activity: useful parameters for characterizing the trophic conditions of lakes

80%

Kiersztyn B. , Siuda W. , Chrost R. J.

Polish Journal of Environmental Studies

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2002

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tom 11

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nr 4

EN

This report describes the relationship between microbial enzymatic activities (aminopeptidase, esterase, and alkaline phosphatase) and the trophic state index of the studied lakes. Pelagic surface water samples were collected from nineteen lakes (Mazurian Lake District, northeastern Poland), characterized by different degrees of eutrophication, during spring homothermy and summer thermal stratification periods in 1999 and 2000. Aminopeptidase and esterase activities of microbial assemblages in unfiltered water samples were positively proportional to the trophic conditions of the studied lakes and both enzymes significantly correlated with Carlson's trophic state index of lakes. No correlation between alkaline phosphatase activities and the trophic state index of the studied lakes was found. This study showed that the selected parameters of microbial activity are very useful for the rapid determination of actual trophic conditions in lake ecosystems.

9

The Relationship between Primary Production and Respiration in the Photic Zone of the Great Mazurian Lakes (GMLS), in Relation to Trophic Conditions, Plankton Composition and Other Ecological Factors

70%

Siuda W. , Kauppinen E. S. , Kaliński T. , Chróst R. J. , Kiersztyn B.

Polish Journal of Ecology

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2017

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tom Vol. 65, nr 3

303--323

EN

The relation of primary production to respiration and dependence of both processes on various environmental factors were investigated in the surface waters of lakes of The Great Mazurian Lake System (GMLS) during summer seasons 2009-2011. Primary production and extracellular release was determined by 14C method, respiration (dark oxygen consumption) - by Winkler's method. Collected results allow to conclude that: (i) in all studied lakes primary production was primarily cyanobacterial, although in mesotrophic ones participation of eukaryotic phytoplankton in light CO2 fixation was more pronounced; (ii) in mesotrophic part of GMLS primary production was limited alternately by N and P availability and less dependent on N and P regeneration processes, whereas in southern, eutrophic lakes it was primarily fueled by regeneration of biogenic substances from organic compounds and strongly limited by N resources; (iii) although in photic zone of whole GMLS respiration was dominated by heterotrophic bacteria, in its mesotrophic part also participation of other plankton components in respiration processes was significant and, (iv) that in eutrophic lakes planktonic respiration was more dependent on low molecular weight products liberated enzymatically from organic substrates than on organic compounds released by primary producers. The mean production to respiration ratio, which varied from 2.11 to 2.60 in northern, and from 2.05 to 3.67 in southern lakes suggested that during period of investigations photic zones of lakes of both parts of GMLS were net autotrophic systems.

10

The relationship between primary production and respiration in the photic zone of the Great Mazurian Lakes (GMLS), in relation to trophic conditions, plankton composition and other ecological factors

70%

Siuda W. , Kauppinen E. S. , Kalinski T. , Chrost R. J. , Kiersztyn B.

Polish Journal of Ecology

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2017

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tom 65

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nr 3

EN

The relation of primary production to respiration and dependence of both processes on various environmental factors were investigated in the surface waters of lakes of The Great Mazurian Lake System (GMLS) during summer seasons 2009–2011. Primary production and extracellular release was determined by ¹⁴C method, respiration (dark oxygen consumption) - by Winkler's method. Collected results allow to conclude that: (i) in all studied lakes primary production was primarily cyanobacterial, although in mesotrophic ones participation of eukaryotic phytoplankton in light CO₂ fixation was more pronounced; (ii) in mesotrophic part of GMLS primary production was limited alternately by N and P availability and less dependent on N and P regeneration processes, whereas in southern, eutrophic lakes it was primarily fueled by regeneration of biogenic substances from organic compounds and strongly limited by N resources; (iii) although in photic zone of whole GMLS respiration was dominated by heterotrophic bacteria, in its mesotrophic part also participation of other plankton components in respiration processes was significant and, (iv) that in eutrophic lakes planktonic respiration was more dependent on low molecular weight products liberated enzymatically from organic substrates than on organic compounds released by primary producers. The mean production to respiration ratio, which varied from 2.11 to 2.60 in northern, and from 2.05 to 3.67 in southern lakes suggested that during period of investigations photic zones of lakes of both parts of GMLS were net autotrophic systems.

11

The Role of Planktonic Organisms in Urea Metabolism in Lakes of Temperate Zone : Case Study

70%

Siuda W. , Chróst R. J. , Kalinowska K. , Ejsmont-Karabin J. , Kiersztyn B.

Polish Journal of Ecology

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2016

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tom Vol. 64, nr 4

468--484

EN

Although urea is the simplest N-containing organic compound ubiquitous in all aquatic environments, its role in N-nutrition of planktonic biota and relevance for eutrophication of freshwater ecosystems is still insufficiently defined and often bypassed. The dynamics of production of autochthonous urea as well as maximal potential net ureolytic activity (net URA Vmax) of phyto- and bacterioplakton were studied in mesocosm experiment and verified during the field studies conducted in the Great Mazurian Lake system (GMLS). Analysis of the obtained results revealed that the proteins were the main autochthonous urea precursors. Urea concentration in the studied mesocosms and in GMLS surface waters was positively correlated with flagellate, ciliate and crustacean biomass and, less evidently, with bacterial biomass (BB). In surface waters of GMLS net URA Vmax, similarly as urea concentrations, increased with their trophic status. Analysis of correlation of potential ureolytic activity with chlorophylla, (Chla) BB and L-leucine aminopeptidase activity (AMP) in lakes of different trophic status suggests that although both groups of planktonic microorganisms participated in urea decomposition processes, in eutrophic ones bacterial decomposition of urea is more evident. In highly eutrophic lakes excess of phosphorus induced higher nitrogen requirement resulting in the increase in protein decomposition rate. Intensified protein degradation resulted faster urea production, which finally induced higher ureolytic activity of planktonic microorganisms. In profundal waters of GMLS potential ureolytic activity was distinctly lower than in surface waters. This was caused by low temperature of hypolymnetic waters, inhibitory effect of hydrogen sulphide and lack of phytoplankton, which is known as a primary urea consumer.

12

The role of planktonic organisms in urea metabolism in lakes of temperate zone – case study

70%

Siuda W. , Chrost R. J. , Kalinowska K. , Ejsmont-Karabin J. , Kiersztyn B.

Polish Journal of Ecology

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2016

|

tom 64

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nr 4

EN

Although urea is the simplest N-containing organic compound ubiquitous in all aquatic environments, its role in N-nutrition of planktonic biota and relevance for eutrophication of freshwater ecosystems is still insufficiently defined and often bypassed. The dynamics of production of autochthonous urea as well as maximal potential net ureolytic activity (net URA Vmax) of phyto- and bacterioplakton were studied in mesocosm experiment and verified during the field studies conducted in the Great Mazurian Lake system (GMLS). Analysis of the obtained results revealed that the proteins were the main autochthonous urea precursors. Urea concentration in the studied mesocosms and in GMLS surface waters was positively correlated with flagellate, ciliate and crustacean biomass and, less evidently, with bacterial biomass (BB). In surface waters of GMLS net URA Vmax, similarly as urea concentrations, increased with their trophic status. Analysis of correlation of potential ureolytic activity with chlorophyllₐ, (Chlₐ) BB and L-leucine aminopeptidase activity (AMP) in lakes of different trophic status suggests that although both groups of planktonic microorganisms participated in urea decomposition processes, in eutrophic ones bacterial decomposition of urea is more evident. In highly eutrophic lakes excess of phosphorus induced higher nitrogen requirement resulting in the increase in protein decomposition rate. Intensified protein degradation resulted faster urea production, which finally induced higher ureolytic activity of planktonic microorganisms. In profundal waters of GMLS potential ureolytic activity was distinctly lower than in surface waters. This was caused by low temperature of hypolymnetic waters, inhibitory effect of hydrogen sulphide and lack of phytoplankton, which is known as a primary urea consumer.