Wyniki wyszukiwania - Biblioteka Nauki

1

Antibiotic resistance in marine neustonic and planktonic bacteria isolated from the Gdańsk Deep

100%

Mudryk Z. , Skorczewski P.

Oceanologia

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1998

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tom No. 40 (2)

125-136

EN

This study deals with the antibiotic resistance of heterotrophic bacteria isolated from the surface and subsurface water of the Gdansk Deep. The level of resistance of bacteria to various antibiotics differed considerably. As a rule, there were no significant differences in antibiotic resistance between neustonic and planktonic bacteria. Considerable diel fluctuations in bacterial antibiotic resistance were found. There were significant differences between pigmented and non-pigmented bacteria in their resistance to the tested antibiotics. Bacterial resistance to antibiotics was dependent on their chemical structure.

2

A novel Virbio hraveyi mutant with altered quorum sensing regulation

100%

Czyż A. , Zielke R. , Węgrzyn G.

Oceanological and Hydrobiological Studies

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2005

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tom Vol. 34, No.2

55--61

EN

The expression of genes involved in the luminescence (lux genes) of many light-emitting bacteria, including the marine bacterium Vibrio harveyi, is regulated by a phenomenon called quorum sensing. The expression of the lux genes, and thus the efficiency of light emission, depends on the concentration of cells in the environment. Bacterial luminescence is effective when cells occur at high density, whereas light emission is negligible in diluted cultures. Quorum sensing regulation is a complex process which requires the functioning of many genes. The current paper describes the recently isolated novel V. harveyi mutant, which now appears to be impaired in quorum sensing. The mutant produces autoinducers normally, but it is partially defective in responding to these molecules, thus its quorum sensing reaction is delayed relative to wild-type bacteria.

3

Phylogenetic relationship of the stringent response-related genes of marine bacteria

100%

Guzow-Krzemińska B. , Gąsior T. , Szalewska-Pałasz A.

Acta Biochimica Polonica

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2015

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tom 62

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nr 4

773-783

EN

Bacteria living in marine environment encounter various challenges and limitations, thus in order to survive, they need to employ efficient stress-response mechanisms. One of these mechanisms is the stringent response, where unusual nucleotides, guanosine tetra- and pentaphosphates, herald starvation and physico-chemical stresses. All so far sequenced free-living bacteria contain the gene(s) responsible for (p)ppGpp synthesis - rsh (named after Escherichia coli genes, relA and spoT). Two similar genes were identified mostly in β- and γ-proteobacteria while other bacteria have only one gene coding the dual function of (p)ppGpp synthesis and degradation. Although the presence of (p)ppGpp-mediated response to the stress conditions has been shown for a few, and predicted for some other marine microorganisms, the (p)ppGpp effects may vary among different organisms. Thus, in this work we asked whether marine bacteria could have evolved a genetic adaptation specifically suited to adapt to environment with limited resources. The phylogenetic analyses of SpoT, RelA and RSH proteins from organisms associated with marine environment showed, however, that the evolutionary correlations obtained for these proteins are congruent with those constructed for 16S rRNA sequences and reflect taxonomical relationships of these organisms. Likewise, the similarity of specific amino acid residues indispensable for catalytic activity of these enzymes is very high, and any observed changes parallel with the taxonomical and evolutionary relationships. However, potential homologs of Mesh1 enzyme (metazoan SpoT homologs) that occur in both eukaryotic and prokaryotic organisms and contain the hydrolytic domain orthologous to SpoT were identified in Cellulophaga, Erythrobacter and Flavobacterium genera for the first time, as well as in soil bacterium Cytophaga hutchinsonii and freshwater Rhodothermus marinus.

4

Extracellular hydrolytic enzyme production by proteolytic bacteria from the Antarctic

88%

Tropeano M. , Vázquez S. , Coria S. , Turjanski A. , Cicero D. , Bercovich A. , Mac Cormack W.

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5

Zeaxanthin biosynthesis by members of the genus Muricauda

88%

Prabhu S. , Rekha P. D. , Arun A. B.

Polish Journal of Microbiology

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2014

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tom 63

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nr 1

EN

Zeaxanthin, a C₄₀ xanthophyll carotenoid, has potential biological applications in nutrition and human health. In this study we characterized carotenoid composition in 5 taxonomically related marine bacterial isolates from the genus Muricauda. The pigment was characterized using high performance liquid chromatography (HPLC) and mass spectrometry, which confirmed the presence of all-trans-zeaxanthin. Muricauda strains produced zeaxanthin as a predominant carotenoid. M. flavescens JCM 11812T produced highest yield (4.4 ± 0.2 mg L⁻¹) when cultured on marine broth at 32°C for 72 h. This is the first report on the presence of zeaxanthin among the majority of species from the genus Muricauda.

6

Abundance and morphotype diversity of surface bacterioplankton along the Gdynia - brest transect

88%

Żmuda M. J.

Oceanological and Hydrobiological Studies

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2005

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tom Vol. 34, No.4

3--17

EN

Abundance, biomass and morphotype diversity of bacterioplankton were analyzed in surface samples collected on a transect from Gdynia (Poland) to Brest (France) between 5 and 17 October, 2002. The total bacterial number ranged from 1.52 x 105 š 7.0 x 103 ml-1 (SE) to 4.08 x 106 š 3.1 x 105 ml-1. Samples from the Baltic Sea showed both the highest number of bacteria and the largest variability. Total bacterial biomass ranged from 5.45 š 0.99 to 128.17 š 13.58 ěg C l-1. The dominant morphotype were rods (82.4% to 95.7%) especially those with average cell volume below 0.1 ěm3. Regional differences in the average cell volume ranged from 0.099 to 0.382 ěm3. Autotrophic bacteria comprised on average 13.5 % of total bacterioplankton biomass, but increased to 48% at the west side of the English Channel. The high bacterial abundances discussed here shed light on the importance of the ocean surface as a habitat for prokaryotes and as a reservoir of bacterial biomass.

7

A novel Vibrio harveyi mutant with altered quorum sensing regulation

88%

Czyz A. , Zielke R. , Wegrzyn G.

Oceanological and Hydrobiological Studies

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2005

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tom 34

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nr 2

8

Antifouling activity of bacterial extracts associated with soft coral and macroalgae from the Red Sea

75%

Tunkal R. I. , Jamal M. T. , Abdulrahman I. , Pugazhendi A. , Satheesh S.

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tom Vol. 51, No. 4

325--336

EN

In marine environments where biofouling occurs and has an impact on the maritime economy and environment, compounds that inhibit the attachment, growth and survival of microorganisms in a biofilm complex as well as settlement of larvae are considered potential antifouling compounds. In this study, the extracellular metabolites from two surface- associated bacteria isolated from soft coral and macroalga were evaluated for antibiofilm and antisettlement activity. The bacteria were identified using 16S rRNA gene sequencing, and the culture supernatant extract of each strain was evaluated for antibiofilm activity. The compounds present in the extracts were analysed using GC-MS. The two bacterial strains were identified as Bacillus licheniformis MBR1 and Vibrio alginolyticus MBR4 for the isolates from soft coral and macroalgae, respectively. The extracts inhibited the growth of biofilm-forming bacteria, biofilm formation and barnacle larval settlement. The GC-MS analysis of the extract detected the presence of compounds such as tetrapentacontane, octadecanoic acid, 2,3-dihydroxypropyl ester, hexadecanoic acid, 2-hydroxy-1-(hydroxymethyl) ethyl ester and 17-pentatriacontene. The results of the study show that extracellular metabolites of the bacteria associated with marine organisms could be used as natural antifouling compounds to control biofouling.

9

Bioremediation of petroleum contaminated sands with bacteria cultures

75%

Przystaś W. , Pasadakis N. , Kalogerakis N.

Architecture Civil Engineering Environment

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2010

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tom Vol. 3, no. 3

105-114

EN

Accidental oil spills at open sea is a common environmental problem. However, we are faced with a much more severe problem once the oil spill reaches the shoreline. Current oil spill combating practice is to collect manually the polluted sand and proceed with disposal or temporary storage in nearby sites. Addition of mixed bacterial cultures into petroleum contaminated sand was examined. Experiments with sand polluted by 5% (v/w) of crude oil were performed in sterile and non-sterile conditions to see the degradation potential of isolated cultures, their growth characteristics and possible antagonisms between supplemented microorganisms and natural microflora. During the experiments the oxygen demand was monitored. Correlation between high oxygen demand and high depletion of hydrocarbons was observed. The best TPH removal in sterile conditions was found in samples with the mixed cultures isolated from waste sludge from petroleum refinery Motor Oil Hellas (Korinth Refineries, Greece). For this culture concentration of hydrocarbons in sterile sand was 73.2% lower than in control sample. In non-sterile sand concentration of TPH after 14 days was 70.5% lower than in control (sterile sand) without bioaugmentation. The lowest depletion of hydrocarbons was observed in sample with addition of mixed culture (AM) of Alcanivorax borcumensis (DSM 11573) and Marinobacter hydrocarbonoclasticus (DSM 8798) (32.9%). Finally, the addition of artificial seawater and fertilizers had also a positive influence on contaminants depletion by naturally occurring microorganisms (48%).

PL

Powszechnym problemem środowiskowym są przypadkowe wycieki paliw na otwartym morzu. Z jeszcze bardziej uciążliwym problemem spotykamy się jednakże w momencie dotarcia wycieku do wybrzeża. Obecne praktyki rekultywacyjne polegają na zebraniu zanieczyszczonego piasku i jego usunięciu lub okresowym składowaniu na pobliskich terenach. Celem badań było określenie wpływu inokulacji mieszanymi kulturami bakteryjnymi piasku zanieczyszczonego surową ropą naftową. Badania prowadzono na piasku zanieczyszczonym 5% (v/w) surowej ropy naftowej w warunkach sterylnych i niesterylnych tak, aby zaobserwować zdolność wyizolowanych kultur do degradacji zanieczyszczenia, scharakteryzować ich wzrost oraz możliwe antagonizmy między wprowadzonymi mikroorganizmami a naturalną mikroflorą. Zaobserwowano dodatnią korelację miedzy ubytkiem tlenu i wysokim ubytkiem węglowodorów. Najwyższy stopień usunięcia TPH w warunkach sterylnych zaobserwowano w próbach z mieszaną kulturą wyizolowaną z osadu pochodzącego z rafinerii Motor Oil Hellas (Korinth Refineries, Grecja). Stężenie ropopochodnych w próbie z tą kulturą i sterylnym piaskiem było o 72.3% niższe niż w kontroli. W warunkach niesterylnych stężenie TPH po 14 dniach było niższe niż w kontroli (piasek sterylny) o 70.5%. Najniższy ubytek węglowodorów zaobserwowano w próbach zaszczepionych mieszaniną kultur (AM) zawierających Alcanivorax borcumensis (DSM 11573) i Marinobacter hydrocarbonoclasticus (DSM 8798) (32.9%). Wreszcie zaobserwowano, iż dodatek sztucznie spreparowanej wody morskiej i biogenów miały również pozytywny wpływ na ubytek zanieczyszczeń spowodowany działalnością autochtonicznych mikroorganizmów (48%).

10

Utilization of dissolved amino acids by marine bacteria isolated from the surface and subsurface layers of the Gdansk Deep

75%

Mudryk Z. , Skorczewski P.

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tom 07

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nr 5

11

The use of marine bacteria in mutagenicity assays

63%

Podgorska B. , Wegrzyn G.

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tom 56

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nr 4

EN

Mutagenic pollution of environment is a global and important problem. This includes marine environment. Although many mutagenicity assays have been developed, there are specific problems with testing marine water and sediments for mutagenic contamination. One of them is the fact that most of genetically modified strains used in commonly available microbiological mutagenicity assays, like Escherichia coli or Salmonella, survive relatively poorly in marine waters, especially those of higher salinity. Thus, alternative assays have been developed, in which bacteria occurring naturally in marine habitats are employed. These assays, reviewed in this article, appear to be useful in testing not only marine samples but also can be used in other approaches, which involve detection and estimation of the amount of mutagenic compounds.

12

Cloning of the groE operon of the marine bacterium Vibrio harveyi using a lambda vector

63%

Kuchanny D. , Klein G. , Krzewska J. , Czyz A. , Lipinska B.

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nr 1

EN

groES and groEL genes encode two co-operating proteins GroES and GroEL, belonging to a class of chaperone proteins highly conserved during evolution. The GroE chaperones are indispensable for the growth of bacteriophage λ in Escherichia coli cells. In order to clone the groEL and groES genes of the marine bacterium Vibrio harveyi, we constructed the V. harveyi genomic library in the λEMBL1 vector, and selected clones which were able to complement mutations in both groE genes of E. coli for bacteriophage λ growth. Using Southern hybridization, in one of these clones we identified a DNA fragment homologous to the E. coli groE region. Analysis of the nucleotide sequence of this fragment showed that the cloned region contained a sequence in 71.7% homologous to the 3' end of the groEL gene of E. coli. This confirmed that the λ clone indeed carries the groE region of V. harveyi. The positive result of our strategy of cloning with the use of the genomic library in λ vector suggests that the same method might be useful in the isolation of the groE homologues from other bacteria. The V. harveyi cloned groE genes did not suppress thermosensitivity of the E. coli groE mutants.

13

Survival in extremes

51%

Malecki P. H. , Rypniewski W.

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nr 1

14

Exposure to chlorine affects the extracellular polymeric substance production and cell surface hydrophobicity in biofilm bacteria

51%

Rathi R. , Satheesh S.

Oceanological and Hydrobiological Studies

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2012

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tom 41

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nr 4

15

Degradation of crude oil in seawater and sand by mixed bacterial cultures

51%

Przystaś W. , Pasadakis N. , Kalogerakis N.

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tom Vol. 32, no. 1

43-58

EN

Accidental oil spills at open sea is a common environmental problem. They lead to degradation of sea and shoreline life. In the last ten years there has been an increased interest in bioremediation using the enzymatic activity of the naturally occurring microorganisms. In this work the potential of mixed microbial cultures for biodegradation of crude oil in seawater and sand has been examined. Artificial seawater supplemented with nitrogen and phosphorus was inoculated with cultures isolated from refinery sludge. The same cultures were used for experiments in sand polluted by 5% (v/w) of crude oil. These experiments were performed in sterile and semi-natural (not sterile) conditions to see the degradation potential of isolated cultures, their growth characteristics and possible antagonisms between supplemented microorganisms and natural microflora. During the experiments the oxygen demand, number of bacteria (cfu) and optical density (ODH|1) were monitored. After 14 days of cultivation, the concentration of total petroleum hydrocarbons (TPH) in all samples was measured. All tested cultures had a potential for degradation of hydrocarbons in seawater and sand. After two weeks of experiment, loss of hydrocarbons in seawater polluted with crude oil was between 56.8% (A2 culture) and 64.4% (Al culture). The most effective culture for bioaugmentation of seawater does not have to be the best solution for bioaugmentation of sand. In sand the best degraders in sterile and semi-natural conditions were found in the mixed cultures isolated from Corinth refinery sludge. For this culture concentration of hydrocarbons in sterile sand was 73.2% lower than in control sample and in non-sterile sand 70.5% lower than in control (sterile sand) without bioaugmentation. Finally, the addition of seawater and fertilizers to sand had also a positive influence on contaminants degradation by naturally occurring microorganisms (48%). Experiments performed with different environments (seawater and sand) and under different conditions (sterilized material and semi-natural conditions) confirmed that cultures should be tested in semi-natural conditions especially when indigenous microflora cans posse's high degradation potential. Allochtonic cultures, very active in sterile conditions, after inoculation to natural environment can even slow down the degradation.

PL

Przypadkowe wycieki ropy na otwartym morzu są częstym problemem środowiskowym prowadzącym do degradacji życia morskiego jak i życia na wybrzeżu. Obecnie techniki są skoncentrowane na zebraniu oleju, wypaleniu in-situ pozostałości ropy, zbieraniu zanieczyszczonego piasku i likwidowaniu zanieczyszczeń lub magazynowaniu go na terenach przyległych. W ciągu ostatnich lat wzrosło zainteresowanie bioremediacją z użyciem mikroorganizmów aktywnych w rozkładzie zanieczyszczeń ropopochodnych. Celem tej pracy było sprawdzenie zdolności mikroorganizmów wyizolowanych ze środowisk zanieczyszczonych do biodegradacji ropy naftowej w wodzie morskiej oraz w piasku pobranym z wybrzeża. Sztuczna woda morska wzbogacona biogenami została zaszczepiona bakteriami wyizolowanymi z osadów rafineryjnych. Te same kultury zostały użyte również w doświadczeniu z piaskiem pobranym z wybrzeża Krety. Badania z użyciem piasku zanieczyszczonego 5% (v/w) ropy naftowej były przeprowadzone po jego uprzednim wysterylizowaniu i bez poddania go sterylizacji. Takie modyfikacje miały na celu: wykazanie, czy wyizolowane kultury potrafią sobie radzić z zanieczyszczeniem w warunkach semi-naturalnych oraz scharakteryzowanie ich wzrostu i możliwości wystąpienia reakcji antagonistycznych pomiędzy inokulowanymi szczepami a mikroflorą naturalną. W trakcie eksperymentu mierzono zużycie tlenu, liczebność bakterii (cfu) i gęstość optyczną prób. Po zakończeniu eksperymentów (po 14 dniach) zmierzono zawartość węglowodorów ropopochodnych (TPH - total petroleum hydrocarbons) przy użyciu spektrofotometrii w podczerwieni (IR). Wszystkie testowane kultury mieszane posiadały zdolność do rozkładu węglowodorów w wodzie morskiej i piasku. Po dwóch tygodniach eksperymentu usunięcie TPH w wodzie morskiej zanieczyszczonej ropą naftową było pomiędzy 56,8% (dla A2) i 64,4% (dla Al). Stwierdzono, iż kultury najefektywniej usuwające węglowodory w wodzie morskiej nie są najlepszymi dla piasku. W piasku najlepszy rozkład węglowodorów obserwowano w próbach zaszczepionych mieszaniną bakterii wyizolowanych z osadów rafinerii w Koryncie. Zawartość węglowodorów była odpowiednio o ponad 70% niższa niż w odpowiadającym kontrolach nieinokulowanych. Zaobserwowano, iż dodatek wody morskiej wzbogaconej biogenami do Piasku miał również pozytywny wpływ na usunięcie węglowodorów przez naturalnie występujące w piasku mikroorganizmy (48%). Otrzymane wyniki wskazują na konieczność przeprowadzania analiz w warunkach mi-naturalnych zwłaszcza, gdy autochtoniczna mikroflora może posiadać wysoki potencjał degradacyjny. a mikroflora wprowadzona do środowiska może nie tylko nie przyspieszyć rozkładu zanieczyszczeń, ale i go spowolnić

16

Utilization of low molecular weight organic compounds by marine neustonic and planktonic bacteria

51%

Donderski W. , Mudryk Z. , Walczak M.

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tom 07

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nr 5

EN

The efficiency of utilization of low molecular weight organic molecules by neustonic and planktonic bacteria inhabiting the waters of the Gdańsk Deep region has been determined. The most intensive growth was observed in the presence of amino acids, while carbohydrates and organic acids were utilized less actively. Glutamic acid, asparatic acid, histidine, glycine, cysteine and calcium lactate were the most suitable sources of carbon and energy for the bacteria. Significant differences in the level of intensity of assimilation of low molecular weight organic molecules by bacteria inhabiting various water layers occurred.

17

Factors regulating bacterial abundance in Antarctic coastal and shelf waters

51%

Zdanowski M. K.

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tom 19

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nr 3-4

18

Abundance and morphotype diversity of surface bacterioplankton along the Gdynia - Brest transect

51%

Zmuda M. J.

Oceanological and Hydrobiological Studies

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2005

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tom 34

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nr 4

19

How do marine bacteria produce light, why are they luminescent, and can we employ bacterial bioluminescence in aquatic biotechnology?

51%

Wegrzyn G. , Czyz A.

Oceanologia

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2002

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tom 44

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nr 3

EN

Bioluminescence, the phenomenon of light production by living organisms, occurs in forms of life as various as bacteria, fungi and animals. Nevertheless, light-emitting bacteria are the most abundant and widespread of luminescent organisms. Interestingly, most species of such bacteria live in marine environments. In this article, the biochemical mechanism of bacterial luminescence and its genetic regulation are summarized. Although the biochemistry and genetics of light emission by cells have been investigated in detail, the biological role of bacterial luminescence has remained obscure. Here, we discuss recent discoveries that shed new light on this problem. Finally, we provide examples of how bacterial luminescence can be employed in marine biotechnology, especially in the detection of toxic and mutagenic pollution in aquatic environments.

20

Chemical and bacteriological studies of surface and subsurface water layers in estuarine Lake Gardno

51%

Mudryk Z. J. , Trojanowski J. , Antonowicz J. , Skorczewski P.

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nr 2

EN

This paper presents results of chemical and bacteriological examinations of surface and subsurface water layers of estuarine lake Gardno. The obtained data indicate that there are substantial differences in chemical compound concentrations and also bacteria number and activity between the water layers under investigation. Particularly great differences between microlayers and subsurface water refer to concentrations of organic phosphorus and nitrogen. It was found that bacteria number was greater in surface water layers than in subsurface water. Significant differences among the studied chemical and bacteriological parameters were revealed between particular sites across lake Gardno. The number of freshwater, brackish and marine bacteria in the water of lake Gardno was up to chlorides concentration.