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1

Mechanism and Effects of Cyanobacterial Hepatotoxin Action on Human Organism

100%

Zyska A., Jasik-Ślęzak J.

Polish Journal of Public Health

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2015

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vol. 124

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issue 3

156-159

EN

Eutrophication of waters and climate warming have created in the last decades favourable conditions for cyanobacteria colonization. The presence of cyanobacteria toxins in heavily polluted lake waters and fish ponds has become a current problem. These toxins belong to cyanobacteria secondary metabolites and are active in various fields of harmfulness to animals and humans. This group includes neurotoxins, dermatotoxins and hepatotoxins having a destructive influence on liver's cells. The group of hepatotoxins comprises microcystins and nodularin. The symptoms of hepatotoxin poisoning include stomach, intestine and liver disorders, intra-liver bleeding and physiological insufficiency of this organ. These compounds can induce apoptosis of liver cells and tumor promoters. From the above facts, it follows that hepatotox-ins can pose a very serious health problem on a global scale. This work presents the characteristic of cyanobacterial hepato-toxins, their chemical structure, properties, and mechanism of their action on human organism. The harmful influence caused by consuming products used in diet supplements, which contain microcystins was also pointed out.

2

EPR study of thylakoid membrane dynamics in mutants of the carotenoid biosynthesis pathway of Synechocystis sp. PCC6803

100%

Kłodawska K., Malec P., Kis M., Gombos Z., Strzałka K.

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2012

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vol. 59

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issue 1

87-90

EN

EPR spectroscopy using 5-doxylstearic acid (5-SASL) and 16-doxylstearic acid (16-SASL) spin probes was used to study the fluidity of thylakoid membranes. These were isolated from wild type Synechocystis and from several mutants in genes encoding selected enzymes of the carotenoid biosynthesis pathway and/or acyl-lipid desaturases. Cyanobacteria were cultivated at 25°C and 35°C under different light regimes: photoautotrophically (PAG) and/or in light-activated heterotrophic conditions (LAHG). The relative fluidity of membranes was estimated from EPR spectra based on the empirical outermost splitting parameter in a temperature range from 15°C to 40°C. Our findings demonstrate that in native thylakoid membranes the elimination of xanthophylls decreased fluidity in the inner membrane region under optimal growth conditions (25°C) and increased it under sublethal heat stress (35°C). This indicated that the overall fluidity of native photosynthetic membranes in cyanobacteria may be influenced by the ratio of polar to non-polar carotenoid pools under different environmental conditions.

3

Combined treatment of toxic cyanobacteria Microcystis aeruginosa with hydrogen peroxide and microcystin biodegradation agents results in quick toxin elimination

88%

Dziga D., Maksylewicz A., Maroszek M., Marek S.

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2018

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vol. 65

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issue 1

133-140

EN

Under some conditions the growth of toxic cyanobacteria must be controlled by treatment with algicidal compounds. Hydrogen peroxide has been proposed as an efficient and relatively safe chemical which can remove cyanobacteria from the environment selectively, without affecting other microorganisms. However, the uncontrolled release of secondary metabolites, including toxins may occur after such a treatment. Our proposal presented in this paper concerns fast biodegradation of microcystin released after cell lysis induced by hydrogen peroxide. The effectiveness of both, Sphingomonas sp. and heterologously expressed MlrA enzyme, in the removal of the toxin from Microcystis aeruginosa culture was investigated. The results indicate that neither Sphingomonas cells nor MlrA are affected by hydrogen peroxide at the concentrations which stop the growth of cyanobacteria. A several-fold reduction in microcystin levels was documented in the presence of these agents with biodegradation ability. Our results provide evidence that such a combined treatment of water reservoirs dominated by microcystin-producing cyanobacteria may be a promising alternative which allows fast elimination of both, the bloom forming species and toxins, from the environment.

4

Ecological background of cyanobacterial assemblages of the northern part of James Ross Island , Antarctica

75%

Komárek J., Elster J., Komárek J., Elster J.

Polish Polar Research

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2008

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vol. 29

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issue 1

5

Experimental investigation of Microcystis aeruginosa cyanobacteria thickening to obtain a biomass for the energy production

63%

Malovanyy M., Zhuk V., Nykyforov V., Bordun I., Balandiukh I., Leskiv G.

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issue 43

6

Zespół niespecyficznych objawów chorobowych po kontakcie z toksycznymi sinicami – opis przypadku

63%

Kisiel A., Pańczyk-Tomaszewska M., Roszkowska-Blaim M.

Pediatria i Medycyna Rodzinna

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2013

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vol. 9

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issue 2

193-196

EN

Environmental pollution results in increasing frequency of cyanobacteria blooms occurrence in water reservoirs. Many genera of cyanobacteria may produce toxins which are dangerous for animal and human health. Intoxication may be a result of drinking contaminated water, eating contaminated fish or seafood but also due to skin exposure in recreational water during cyanobacteria bloom. Signs and symptoms of intoxication are unspecific and vary from less serious like skin irritation to death. Accept from confirmation of having contact with contaminated water or food there are no diagnostic tests available. In Poland cyanobacteria blooms occur especially during heat waves. Bellow we present a case of a girl who suffered from an unspecific syndrome after returning from holidays at The Baltic Sea during cyanobacteria bloom occurrence. Few days after swimming in the sea she presented feeling unwell, with fever, skin irritation, visual disturbances, joint pain, slightly elevated inflammatory indicators and proteinuria. On the basis of clinical presentation and results of additional tests we excluded respiratory, gastrointestinal and urinary tract infection. Signs and symptoms disappeared spontaneously within few days of observation. The fact that cyanobacteria bloom occurrence is increasing over the last few years indicates that cyanobacteria intoxication should be taken under consideration while diagnosing unspecific syndrome in children coming back from holidays at the seaside.

PL

Z uwagi na rosnące zanieczyszczenie środowiska coraz częściej dochodzi do zakwitu sinic w wodach rekreacyjnych. Wiele gatunków sinic może produkować szkodliwe dla zdrowia zwierząt i ludzi cyjanotoksyny. Do zatrucia może dojść na skutek spożycia skażonej wody, ryb lub owoców morza, ale także poprzez bezpośredni kontakt skóry z wodą, w której doszło do zakwitu sinic. Objawy intoksykacji są niespecyficzne, od mniej groźnych, takich jak podrażnienie skóry, do poważnego zagrożenia życia, ze zgonem włącznie. Oprócz udowodnienia kontaktu ze skażoną wodą lub pożywieniem brak jest metod diagnostycznych potwierdzających zatrucie. W Polsce do zakwitu sinic dochodzi przede wszystkim podczas letnich upałów. Poniżej przedstawiamy przypadek dziewczynki, u której wystąpił zespół niespecyficznych objawów chorobowych po powrocie znad Morza Bałtyckiego w okresie zakwitu sinic. W kilka dni po kąpieli w morzu u dziewczynki obserwowano gorsze samopoczucie, gorączkę, podrażnienie skóry, zaburzenia widzenia, bóle stawów łokciowych, nieznaczne podwyższenie wskaźników stanu zapalnego oraz białkomocz. Na podstawie obrazu klinicznego oraz wyników badań dodatkowych wykluczono infekcje dróg oddechowych, nieżyt żołądkowo-jelitowy oraz zakażenie układu moczowego. Objawy choroby ustąpiły samoistnie w ciągu kilkudniowej obserwacji. Wobec narastającego w ostatnich latach problemu zakwitu sinic w zbiornikach wodnych intoksykację cyjanotoksynami należy rozważyć jako potencjalną przyczynę niespecyficznych objawów chorobowych u dzieci powracających znad morza lub jeziora w okresie letnich upałów.

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Mechanism and Effects of Cyanobacterial Hepatotoxin Action on Human Organism

EPR study of thylakoid membrane dynamics in mutants of the carotenoid biosynthesis pathway of Synechocystis sp. PCC6803

Combined treatment of toxic cyanobacteria Microcystis aeruginosa with hydrogen peroxide and microcystin biodegradation agents results in quick toxin elimination

Ecological background of cyanobacterial assemblages of the northern part of James Ross Island , Antarctica

Experimental investigation of Microcystis aeruginosa cyanobacteria thickening to obtain a biomass for the energy production

Zespół niespecyficznych objawów chorobowych po kontakcie z toksycznymi sinicami – opis przypadku