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1

Changes in microbial community structure during adaptation towards polyhydroxyalkanoates production

100%

Ciesielski S., Klimiuk E., Mozejko J., Nowakowska E., Pokoj T.

Polish Journal of Microbiology

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2009

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tom 58

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nr 2

131-139

Polyhydroxyalkanoates (PHAs) are interesting as material for bioplastic production because they are recognized as biodegradable and could be produced from renewable resources. The industrial production of PHAs has already been used in practice by pure cultures. In recent years, many studies have been addressed of PHA production by mixed cultures. Nevertheless, while fermentation strategy to improve the PHA content of biomass, yield and productivity in pure cultures are well defined, knowledge about the operational condition for PHA synthesis by mixed culture is still very limited. The ecology of the microbial community of activated sludge remains largely unknown, primarily because of the difficulty of making detailed observation. Recently, developed molecular techniques allow determination of community composition from DNA extracted directly from biomass samples. This study examined the changes of bacterial communities in activated sludge through application of the molecular technique, ribosomal intergenic spacer analysis (RISA). Microbial communities from anaerobic-aerobic and ammonia limited fermentations were ascertained. The applied operational conditions were shown to select for a restricted microbial population, which were different in term of structure with respect to the initial microbial consortia in the activated sludge used as inoculum.

2

Molecular identification of polyhydroxyalkanoates-producing bacteria isolated from enriched microbial community

86%

Ciesielski S., Pokoj T., Mozejko J., Klimiuk E.

Polish Journal of Microbiology

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2013

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tom 62

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nr 1

Polyhydroxyalkanoates (PHAs) are especially interesting because of their similar properties to synthetic plastics and their potential use as biodegradable polymers. Many strategies have been employed to effectively and economically produce PHAs, among them a production process based on mixed microbial populations, enriched from activated sludge could be one of the alternative technologies. Defining the bacterial species creating these anonymous populations is crucial for the improvement of cultivation strategy. Moreover, enriched bacterial populations could be a promising source for microbes, useful in many biotechnological projects. The main object of this study was to characterize the microorganisms creating the microbial consortium cultured towards PHAs production. After cultivation, bacteria were identified using the 16S rRNA gene sequencing approach. The presence of genes engaged in PHAs synthesis was detected using PCR. The performed analysis revealed that among eleven isolated bacterial strains, four possessed the ability of polyhydroxybutyrate synthesis.

3

The challenges of incorporating realistic simulations of marine protists in biogeochemically based mathematical models

86%

Davidson K.

Acta Protozoologica

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2014

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tom 53

|

nr 1 Spec.is. Marine Heterotrophic Protists

4

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Effects of climate change on microbial community structure and function in the Antarctic glacier lagoon

86%

Swiatecki A., Gorniak D., Jankowska K., Zdanowski M. K., Borsuk P., Zmuda-Baranowska M. J., Grzesiak J.

Papers on Global Change

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2010

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nr 17

One of the dramatic effects of global warming is the retreat of glaciers. This phenomenon has intensified in the last two decades. Postglacial areas are quickly colonised by various groups of organisms. Auto- and heterotrophic microorganisms play an especially vital role in these processes. They thrive in shallow glacial lagoons which often form in front of retreating glaciers. These reservoirs are characterised by high dynamics of physicochemical parameters, including: salinity, temperature and concentrations of organic compounds and nutrients. The conducted microbiological studies have revealed rich structural and functional diversity of bacteria occurring in the ecosystem of Ecology Lagoon situated on King George Island. Bacteria found on the surface of algae and stones in the shore zone of the lagoon showed particularly intense metabolic activity. A molecular analysis has indicated that unique taxonomic groups of bacteria occur in the ecosystem of Ecology Lagoon.

5

Microbial community at the front of Ecology Glacier [King George Island, Antarctica]: Initial observations

86%

Grzesiak J., Zmuda-Baranowska M., Borsuk P., Zdanowski M.

Polish Polar Research

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2009

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tom 30

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nr 1

37-47

6

Effects of agricultural land use change on fungal community composition

86%

Wu M., Zhong G., Meng D., Wei W.

Polish Journal of Ecology

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2015

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tom 63

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nr 3

Anthropogenic disturbances, such as tillage, management practices, and fertilization, can influence soil microbial communities, but little is known about the effects of land use type on soil fungal communities. In this study, fungal abundance, diversity and community composition in soils were analyzed, to determine the impacts of different agricultural land use types, including old rice paddies (ORP), the long-term and (LTV), short-term (STV) cultivation of vegetables and Magnolia nursery plantations (MNP). Compared to the soils in ORP, the fungal abundance, determined by real-time quantitative polymerase chain reaction, was significantly higher in soils from LTV fields and lower in those from MNP; the copy numbers of the fungal ITS genes in the LTV soils were 30 times greater than in the MNP soils. The terminal restriction fragment length polymorphism (T-RFLP) results showed that the fungal community composition was obviously different in the different soils, based on land use type. Only three T-RFs were found in the soils from the LTV fields, followed by seven in the STV soils and nine in the MNP soils; the most (11) T-RFs were found in the ORP soils. Of the measured soil chemical properties, SOC, available P and NO₃⁻-N were the dominant factors that influenced the fungal communities based on the canonical correspondence analysis (CCA). The present study showed that conversion from paddy soil to vegetable cultivation changed soil properties, decreased soil fungal diversity, increased fungal abundance, and shifted fungal community composition.

7

Structure of microbial community in soils contaminated with heavy metals assessed by culture and fatty acid approaches

86%

Piotrowska-Seget Z.

Prace Naukowe Uniwersytetu Śląskiego w Katowicach

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2005

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nr 2340

8

Surface microlayer in lakes of different trophic status: dissolved organic matter and microbial community

86%

Kostrzewska-Szlakowska I.

Polish Journal of Ecology

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2005

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tom 53

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nr 3

The aim of this paper was to recognize the abundance and frequency of occurrence of neustonic organisms (i.e. bacteria and algae) and accumulation of organic matter in the surface microlayer of three lakes of various trophic status. Water samples of surface microlayer (0.5–0.6 mm) were taken (with Larsson plate) as well as from respective epilimnion layer (0.5 m deep). The samples were collected from shallow, humic (Sphagnum bog) lake (L. Flosek), shallow, eutrophic (L. Zełwążek) and deeper, mesotrophic lake (L. Kuc) in the period May–October during several years. The ratio of the organisms’ density in the surface microlayer to that in deeper (0.5 m) layer was considered as the enrichment factor (Ef). Heterotrophic bacteria accumulation in the surface microlayer was more frequent in the humic lake (75% of samples), than in mesoand eutrophic lakes (64%). Mean Ef values for bacteria ranged from 1.3 to 1.4. Frequent, but not strong accumulation of dissolved organic matter measured as the absorbance A₂₄₅ was noted in the surface microlayer. Dissolved organic carbon (DOC) measured in automatic analyzer showed much stronger accumulation in microlayer, particularly in humic lake. Concentration of chlorophyll a in the surface microlayer was found as the most fluctuating and the highest mean Ef value was found in the mesotrophic lake (Ef = 6.3). An attempt was undertaken to explain these differences between the lakes in terms of variable ratio between allochthonous and autochthonous production in humic, mesotrophic and eutrophic lakes.

9

Changes in soil microbial communities as a result of growing Brassicaceae crops

72%

Majchrzak B., Kurowski T. P., Wachowska U., Jazwinska E.

Acta Agrobotanica

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2010

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tom 63

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nr 1

The study was conducted in 2006 – 2008 at the Production and Experimental Station of the University of Warmia and Mazury in Olsztyn, located in Bałcyny (NE Poland). The objective of this study was to determine the microbial quality of soil after Brassicaceae grown as forecrops for winter wheat. A field experiment was established on grey-brown podsolic soil, and it involved the following forecrops: winter rapeseed, spring rapeseed, white mustard, Chinese mustard, and winter wheat as control. Soil samples for microbiological analyses were collected in the spring, before the sowing of forecrops, and in the autumn, after the harvest of Brassicaceae and ploughing-in crop residues. Bacterial and fungal communities isolated from soil sown with Brassicaceae as forecrops were generally more abundant and diverse. These communities exerted an inhibitory effect on the growth of soil pathogens. Forecrops with the greatest microbiological potential were white mustard and winter rapeseed.

10

Changes in microbial communities of nitrifying immobilized biomass: the role of operational conditions

72%

Zielinska M., Cydzik-Kwiatkowska A., Wojnowska-Baryla I.

Polish Journal of Environmental Studies

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2012

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tom 21

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nr 4

Our research determined the impact of operational conditions on the quantity of total and ammonia-oxidizing bacteria (AOB) in immobilized biomass. The experiment was conducted for two kinds of wastewater differing in organic carbon concentration at HRTs of 1.5 h, 1.0 h, and 0.5 h. The evaluation of bacteria number was accomplished by using the real-time PCR targeting ammonia monooxygenase (amoA) and 16S rDNA genes. In the absence of organic carbon in the influent, the shortening of HRT from 1.5 h to 0.5 h positively affected the AOB number in immobilized biomass, which reached even 30%. But their activity was limited. In the presence of organic carbon in the influent, the shortening of HRT below 1.5 h resulted in a decline of the abundance of ammonia-oxidizing bacteria and nitrification efficiency.

11

Effects of emergent plant species and growth strategy on microbial community structure and diversity

72%

Wang A.-L.

Polish Journal of Environmental Studies

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2013

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tom 22

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nr 5

A field study was conducted in two adjacent shallow lakes (Aiwan Lake and Qingnian Lake) in Tianjin, China, to investigate the effects of plant species and growth strategy (single or mix) on the microbial community’s structure and diversity in the rhizosphere of emergent plants by phospholipid fatty acid (PLFA) methods. The results demonstrated that microbial biomass was higher in the Typha orientalis (T. orientalis) rhizosphere than that in the Phragmites australis (P. australis) rhizosphere, whether they grew separately or together. The bacterial population of gram-positive bacteria (G⁺) was found to be less than that of the gramnegative bacteria (G⁻) in all samples, and the ratio of G⁺ to G⁻ in the plant rhizosphere was less than that in the non-rhizosphere. The diversity index of plant rhizosphere was higher than that of the non-rhizosphere, and was higher in the T. orientalis rhizosphere than in the P. australis rhizosphere. Cluster analysis demonstrated that microbial community structure was more significantly influenced by plant species than by growth strategy.

12

Eukaryotic microbial communities associated with rock-dwelling foliose lichens: a functional morphological and microecological analysis

72%

Bock N., Anderson O. R.

Acta Protozoologica

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2015

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tom 54

|

nr 4

13

Optimized methods for stabilization of microbal communities specializing in biodegradation of organic environmental contaminants

72%

Augustynowicz J., Kaszycki P., Kus M., Bialecka A., Koloczek H.

Polish Journal of Environmental Studies

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2008

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tom 17

|

nr 5

655-664

The aim of this study was to optimize storage conditions of a microbial community used for degradation of petroleum-derived environmental contaminants. Microorganisms were either freeze-dried or directly frozen (-20°C) in the presence of four stabilizers: trehalose, sucrose, glycerol and DMSO. It was found that preincubation with trehalose and sucrose had a positive impact on cell viability for both tested storage techniques. Disaccharide-stabilized consortia were more biodiverse than control samples (untreated with any protectants) and they retained high xenobiotic biodegradation capabilities. The effect of glycerol and DMSO was unexpectedly poor, contradicting other findings on the protective action of these compounds on monocultures. Higher cell survival was achieved only upon short-term (7 days) freezing, whereas DMSO proved to be lethal in the case of freeze-dried communities. Taking into account practical and economic reasons, the use of sucrose rather than the more expensive trehalose appears as the most efficient method for microbial consortia biostabilization during long-term storage. The experimental work provides some important data concerning the problem of elaboration of improved methods for preserving robust microbial communities to be used in environmental biotechnology practice.

14

Microbial communities in the rhizosphere soil of soybean cultivated after tansy phacelia, winter wheat, white mustard, rye, agrimony and soybean as previous crops

72%

Belkot M., Pieta D.

Journal of Plant Protection Research

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2004

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tom 44

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nr 4

The object of the studies conducted in the years 2000–2002 on a field of 3 years’ monoculture of soybean was rhizosphere soil of soybean cultivated after tansy phacelia, winter wheat, white mustard, rye, agrimony and soybean as previous crops. The purpose of the studies was to determine the effect of cultivating the above listed previous crop plants on the formation of microorganism communities in the rhizosphere soil of soybean. The lowest total number of fungal colonies was found in the rhizosphere soil of soybean cultivated after rye and winter wheat (21.09 × 103 and 22.58 × 103 c. f. u., respectively), while the highest number was found in soil after soybean (36.95 × 103 c. f. u.). The highest total number of bacteria was found in 1 g of dryweight of the rhizosphere soil of soybean cultivated after agrimony, and the lowest after soybean (5.80 × 106 and 4.09 × 106 c. f. u., respectively). The largest proportion of pathogenic fungi was characteristic of the rhizosphere soil of soybean cultivated after soybean, and the smallest – of the rhizosphere soil of soybean after agrimony as a previous crop. The dominating species among pathogenic fungi in all experimental objects was Fusarium oxysporum. The rhizosphere soil of soybean cultivated after soybean was the poorest in saprophytic fungi (35.2% of all isolations). On the other hand, the highest number of saprophytes, including antagonistic ones, was found in the rhizosphere soil of soybean after agrimony and winter wheat.

15

Signature lipid biomarker [SLB] analysis in determining changes in community structure of soil microorganisms

72%

Piotrowska-Seget Z., Mrozik A.

Polish Journal of Environmental Studies

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2003

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tom 12

|

nr 6

Signature lipid biomarker (SLB) analysis is a useful tool for identifying microorganisms and characterizing microbial communities in natural systems. Specific fatty acids, especially phospholipids (PLFA), are essential membrane components, make up a relatively constant proportion of the microorganisms under natural conditions and their patterns provide insight into the bacterial and fungal community structure and biomass. This method is based on direct extraction of fatty acids from cultured bacteria or environmental samples and determining the isolated methyl ester fatty acids (FAME) using gas chromatography (GC). Several PLFAs are useful markers for the detection of the specific groups, and whole cell fatty acid analysis is used for routine identification of microbial species. The fatty acid analysis has been successfully applied for the characterization of microbial communities from agricultural soils, from sites contaminated with heavy metals, aromatic compounds, alkaline dust, acid rain and from other diverse habitats.

16

Unusual bacterial strain closely related to Bacillus insolitus

72%

Sklodowska A., Matlakowska R., Ludwig W.

Acta Microbiologica Polonica

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1996

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tom 45

|

nr 2

17

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

58%

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

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.

18

Inorganic phosphorus and nitrogen modify composition and diversity of microbial communities in water of mesotrophic lake

58%

Chrost R. J., Adamczewski T., Kalinowska K., Skowronska A.

Polish Journal of Microbiology

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2009

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tom 58

|

nr 1

77-90

The effects of inorganic nutrients (N, P) enrichment of mesotrophic lake water on changes in bacterial and protistan (heterotrophic nanoflagellates and ciliates) communities compositions were studied in the mesocosm experiment. Phosphorus (PO₄³⁻) and nitrogen (NH₄⁺) alone and in combination were added to three types of experimental mesocosms. Mesocosms results suggested that simultaneous addition of P and N stimulated phytoplankton growth and production rates of bacterial biomass its turnover rate. Strong positive correlations between chlorophyll a and bacterial secondary production rates suggested that bacteria were mainly controlled by organic substrates released in course of phytoplankton photosynthesis. Both nutrients increased distinctly protistan biomass and resulted in the shift in ciliate community composition from algivorous to large omnivorous species. The response of bacterial numbers and biomass to nutrients addition was less evident. However, intensive grazing caused their dynamic changes. Fluorescence in situ hybridization (FISH) revealed only small changes in bacterial taxonomic composition. There was an apparent shift in dominance from Cytophaga-Flavobacterium to the Alphaproteobacteria group in the mesocosm with simultaneous addition of P and N, which positively related to increased abundance of bacterivorous protists. Experiment demonstrated that inorganic N and P nutrients directly influenced the bottom-down control of microbial communities, which had a crucial effect on morphological diversity of bacteria.

19

Effect of organic phosphorus and nitrogen enrichment of mesotrophic lake water on dynamics and diversity of planktonic microbial communities - DNA and protein case studies [mesocosm experiments]

58%

Chrost R. J., Adamczewski T., Kalinowska K., Skowronska A.

Polish Journal of Microbiology

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2009

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tom 58

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nr 2

163-180

Effects of mesotrophic lake water enrichment with organic phosphorus and nitrogen substrates (DNA and model protein, bovine serum albumin - BSA) on dynamics and diversity of natural microbial communities (bacteria, heterotrophic nanoflagellates, ciliates) were studied in mesocosm experiments. Simultaneous enrichment with DNA and BSA strongly increased the abundance and biomass of all studied groups of microorganisms and induced changes in their morphological and taxonomic structure. The increased participation of large heterotrophic nanoflagellates cells (larger than 10 μm) in their total numbers and shifts in taxonomic and trophic Structure of the ciliates, from algivorous to small bacterivorous, species were observed. Grazing caused changes in bacterial size distribution in all enriched mesocosms. Large (10-50 μm) filamentous bacteria significantly contributed to the total bacterial numbers and biomass. Pronounced increase in populations of (β- and γ-Proteobacteria was found in lake water enriched with organic P and N sources, whereas α-Pmteobacteria did not change markedly in the studied mesocosms. DNA additions stimulated the rates of bacterial secondary production. BSA shortened the rates of bacterial biomass turnover in lake water. Relatively high and constant (~ 30%) percentage contribution of active bacteria (MEM+) in two mesocosms enriched with DNA and DNA+BSA suggested the important role of nucleic acids as a source of phosphorus for bacterial growth, activity and production. Numerous and statistically significant correlations between bacteria and protists indicated the direct and selective predator-prey relationship.

20

Soil development and soil biology on King George Island, maritime Antarctic

58%

Bolter M.

Polish Polar Research

|

2011

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tom 32

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nr 2

Ograniczanie wyników

Changes in microbial community structure during adaptation towards polyhydroxyalkanoates production

Molecular identification of polyhydroxyalkanoates-producing bacteria isolated from enriched microbial community

The challenges of incorporating realistic simulations of marine protists in biogeochemically based mathematical models

Effects of climate change on microbial community structure and function in the Antarctic glacier lagoon

Microbial community at the front of Ecology Glacier [King George Island, Antarctica]: Initial observations

Effects of agricultural land use change on fungal community composition

Structure of microbial community in soils contaminated with heavy metals assessed by culture and fatty acid approaches

Surface microlayer in lakes of different trophic status: dissolved organic matter and microbial community

Changes in soil microbial communities as a result of growing Brassicaceae crops

Changes in microbial communities of nitrifying immobilized biomass: the role of operational conditions

Effects of emergent plant species and growth strategy on microbial community structure and diversity

Eukaryotic microbial communities associated with rock-dwelling foliose lichens: a functional morphological and microecological analysis

Optimized methods for stabilization of microbal communities specializing in biodegradation of organic environmental contaminants

Microbial communities in the rhizosphere soil of soybean cultivated after tansy phacelia, winter wheat, white mustard, rye, agrimony and soybean as previous crops

Signature lipid biomarker [SLB] analysis in determining changes in community structure of soil microorganisms

Unusual bacterial strain closely related to Bacillus insolitus

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

Inorganic phosphorus and nitrogen modify composition and diversity of microbial communities in water of mesotrophic lake

Effect of organic phosphorus and nitrogen enrichment of mesotrophic lake water on dynamics and diversity of planktonic microbial communities - DNA and protein case studies [mesocosm experiments]

Soil development and soil biology on King George Island, maritime Antarctic