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1

Characterization of phycotoxins produced by cyanobacteria

100%

Mazur-Marzec H.

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2006

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tom Vol. 35, No.1

85-109

EN

Cyanobacteria (blue-green algae), photosynthetic prokaryotes, are essential elements of aquatic ecosystems. They produce a great variety of secondary metabolites; some of which have potentially useful pharmaceutical properties as anti-tumour, antibacterial and antiviral agents. Some species of cyanobacteria form blooms and become dominant over other forms of aquatic life. Blooms can deteriorate water quality in a variety of ways. Blooms formed by toxic species are the most harmful, as they can cause poisoning and death of organisms that come into contact with them. In this review, the structure and activity of cyanobacterial toxins are described. The toxins are classified into: hepatotoxins, neurotoxins, dermatotoxins and endotoxic lipopolysaccharides. Hepatotoxic cyclic pentapeptides, microcystins and nodularins, are the most common cyanobacterial toxins that have been identified in strains of Microcystis, Anabaena, Nodularia, Planktothrix (Oscillatoria), Nostoc, Hapalosiphon and Anabaenopsis. Cylindrospermopsin, another cyanobacterial hepatotoxin, is produced mainly by Cylindrospermopsis raciborskii. There are several neurotoxins produced by the cyanobacterial genera Anabaena, Aphanizomenon, Planktothrix and Cylindrospermopsis. Based on their activity, these neurotoxins were classified into anatoxin-a, anatoxin-a(S) and saxitoxins. BMAA is a novel cyanobacterial neurotoxin implicated in the ALS/PDC syndrome in the Chamorro people of Guam. The occurrence and harmful effects of cyanobacterial dermatotoxins and endotoxic lipopolysaccharides are less well recognised.

2

Vertical distribution of cyanobacteria biomass and cyanotoxin production in the polymictic Siemianowka Dam Reservoir (eastern Poland)

63%

Grabowska M. , Mazur-Marzec H.

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nr 1

3

Toxic Nodularia spumigena blooms in the coastal waters of the Gulf of Gdańsk: a ten-year survey

51%

Mazur-Marzec H. , Krężel A. , Kobos J. , Pliński M.

Oceanologia

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2006

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tom No. 48 (2)

255-273

EN

In the Baltic Sea, summer blooms of the filamentous, nitrogen-fixing cyanobacterium Nodularia spumigena are favoured by high P concentrations at low N:P ratios and a salinity range of 5-13 PSU. The blooms are initiated by calm and sunny weather, an elevated surface water temperature and thermal stratification. The mass occurrence of N. spumigena in coastal waters is a matter of special concern, as the cyanobacterium produces nodularin, a potent pentapeptide hepatotoxin. In the Gulf of Gdansk, the large-scale occurrence of N. spumigena was recorded for the first time in 1994. Blooms of a similar intensity occurred in 2001, 2003 and 2004. Nodularin concentrations in freeze-dried bloom samples varied from 0.01 to 4.01 mg g-1 d.w. In the coastal waters of the Gulf of Gdańsk, cell-bound nodularin concentrations in 2004 and 2005 attained maxima of 25852 š 107 žg dm-3 and 3964 š 125 žg dm-3, respectively. Microscopic analysis revealed the presence of diverse N. spumigena forms, with the dominance of curved filaments in bloom samples. The results of in situ studies and remote sensing measurements indicate a high frequency and intensity of cyanobacterial blooms in the Gulf of Gdańsk in the last ten years.

4

Bioaccumulation of microcystins in invasive bivalves: A case study from the boreal lagoon ecosystem

51%

Paldaviciene A. , Zaiko A. , Mazur-Marzec H. , Razinkovas-Baziukas A.

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tom 57

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nr 1

5

Bioaccumulation of microcystins in invasive bivalves: a case study from the boreal lagoon ecosystem

51%

Paldavičienė A. , Zaiko A. , Mazur-Marzec H. , Razinkovas-Baziukas A.

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tom No. 57 (1)

93--101

EN

In the current study we present the first report on the bioaccumulation of microcystins (MC) in zebra mussel Dreissena polymorpha from the eutrophic brackish water Curonian Lagoon. The bioaccumulation capacity was related to age structure of mussels and ambient environmental conditions. We also discuss the relevant implications of these findings for biomonitoring of toxic cyanobacteria blooms in the Curonian Lagoon and potential consequences for D. polymorpha cultivation activities considered for the futures as remediation measure. Samples for the analysis were collected twice per year, in June and September, in 2006, 2007 and 2008, from two sites within the littoral zone of the lagoon. The highest microcystin concentrations were measured in mussels larger than 30 mm length and sampled in 2006 (when a severe toxic cyanobacteria bloom occurred). In the following years, a consistent reduction in bioaccumulated MC concentration was noticed. However, certain amount of microcystin was recorded in mussel tissues in 2007 and 2008, when no cyanotoxins were reported in the phytoplankton. Considering high depuration rates and presence of cyanotoxins in the bottom sediments well after the recorded toxic blooms, we assume mechanism of secondary contamination when microcystin residuals could be uptaken by mussels with resuspended sediment particles.

6

Toxic Nodularia spumigena blooms in the coastal waters of the Gulf of Gdańsk: a ten-year survey

51%

Mazur-Marzec H. , Krezel A. , Kobos J. , Plinski M.

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tom 48

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nr 2

EN

In the Baltic Sea, summer blooms of the filamentous, nitrogen-fixing cyanobacterium Nodularia spumigena are favoured by high P concentrations at low N:P ratios and a salinity range of 5–13 PSU. The blooms are initiated by calm and sunny weather, an elevated surface water temperature and thermal stratification. The mass occurrence of N. spumigena in coastal waters is a matter of special concern, as the cyanobacterium produces nodularin, a potent pentapeptide hepatotoxin. In the Gulf of Gdańsk, the large-scale occurrence of N. spumigena was recorded for the first time in 1994. Blooms of a similar intensity occurred in 2001, 2003 and 2004. Nodularin concentrations in freeze-dried bloom samples varied from 0.01 to 4.01 mg g−1 d.w. In the coastal waters of the Gulf of Gdańsk, cell-bound nodularin concentrations in 2004 and 2005 attained maxima of 25 852±107 μg dm−3 and 3964±125 μg dm−3, respectively. Microscopic analysis revealed the presence of diverse Nodularia forms, with the dominance of curved filaments in bloom samples. The results of in situ studies and remote sensing measurements indicate a high frequency and intensity of cyanobacterial blooms in the Gulf of Gdańsk in the last ten years.

7

Morphological, genetic, chemical and ecophysiological characterisation of two Microcystis aeruginosa isolates from the Vistula Lagoon, Southern Baltic

45%

Mazur-Marzec H. , Browarczyk-Matusiak G. , Forycka K. , Kobos J. , Plinski M.

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nr 1

127-146

EN

The Vistula Lagoon (southern Baltic Sea) is a shallow and highly eutrophic water body, with frequent blooms of cyanobacteria dominated by Microcystis and Anabaena species. Two Microcystis strains, MK10.10 and MAKR0205, isolated from the lagoon were characterised in this work. The morphology of the isolates differed significantly with respect to cell size and their ability to form aggregates. Based on the 16S rRNA sequence and 16S-23S internal transcribed spacer (ITS) sequence, both isolates were classified as Microcystis aeruginosa. However, only one isolate, MK10.10, possessed the mcy genes responsible for microcystin biosynthesis and only this strain produced microcystins. The effects of environmental factors, such as light, temperature and salinity, on toxin production turned out to be minor. Under the culture conditions used in the experiments, the biomass of the toxic MK10.10 was always lower. Hybrid quadrupole-time-of-flight liquid chromatography/tandem mass spectrometry (QTOF-LC/MS/MS) was used to elucidate the structure of the microcystin (MC) variants produced by MK10.10. Based on molecular ion and fragmentation spectra, the toxins were identified as MC-LR, MC-VR and MC- HIlR. Our study confirmed that some morphological criteria could be useful in preliminarily assessing the potential toxicity of a Microcystis bloom.

8

Toxic cyanobacterial blooms in the Kociewskie Lakes [Northern Poland]

45%

Kobos J. , Mazur-Marzec H. , Dittmer M. , Witek B. , Plinski M.

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tom 34

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nr Suppl.3

9

Biotechnological potentialof Baltic cyanobacteria

38%

Mazur-Marzec H. , Ceglowska M. , Fidor A. , Goua M. , Kropidlowska M. , Wieczerzak E. , Edwards C.

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nr S2