GLORIA — GEOMAR Library Ocean Research Information Access

Treffer pro Seite

Treffer 1 - 2 | 2 Treffer

Sortierung

Digitale Medien

Modeling the increase of nodularin content in Baltic Sea Nodularia spumigena during stationary phase in phosphorus-limited batch cultures (2002)

Stolte, Willem ; Karlsson, Chatarina ; Carlsson, Per ; [weitere]

Oxford, UK : Blackwell Publishing Ltd

FEMS microbiology ecology 41 (2002), S. 0

zur Merkliste hinzufügen auf der Merkliste

Details

ISSN: 1574-6941

Quelle: Blackwell Publishing Journal Backfiles 1879-2005

Thema: Biologie

Notizen: Nodularin (Nod), produced by the brackish/marine cyanobacterium Nodularia spumigena, is a potent hepatotoxin, tumor promoter and is possibly carcinogenic to mammals. It is structurally and toxicologically related to the microcystins, produced by Microcystis aeruginosa in fresh water. A better understanding of the kinetics of Nod production might provide an insight into the physiological and ecological function of cyanobacterial hepatotoxins. The present study presents a simple model simulating the concentration of Nod in N. spumigena KAC66 during phosphorus-limited growth. The main assumption of the model is that the Nod production rate is proportional to the chlorophyll-a (Chla) concentration. The model was tuned to data from phosphorus-limited batch cultures of N. spumigena KAC66 at saturating light and was able to predict 96% or more of the variation in both Chla and Nod concentration. No significant effect of available nitrogen source was found on the Chla-specific Nod production rate although specific growth rates were higher in ammonium and nitrate grown cultures compared to cultures grown with N2 as the sole nitrogen source. Literature data on microcystin production by M. aeruginosa in phosphorus-limited chemostats fitted the model predictions well, except at very low dilution rates (0.1 day−1). The good fit with the proposed model to our own and literature data suggests that the production of hepatotoxic cyanotoxins is not regulated upon growth reduction due to phosphate limitation.

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1111/j.1574-6941.2002.tb00982.x

Permalink

	Standort	Signatur	Einschränkungen	Verfügbarkeit

Andere fanden auch interessant ...

Artikel (Nationallizenzen)

Volltext

Digitale Medien

Evidence for multiple species within the endoparasitic dinoflagellate Amoebophrya ceratii as based on 18S rRNA gene-sequence analysis (2000)

Janson, Sven ; Gisselson, Lars-Åke ; Salomon, Paulo S. ; [weitere]

Springer

Parasitology research 86 (2000), S. 929-933

zur Merkliste hinzufügen auf der Merkliste

Details

ISSN: 1432-1955

Quelle: Springer Online Journal Archives 1860-2000

Thema: Biologie , Medizin

Notizen: Abstract Parasitism within the group of dinoflagellates is a widespread phenomenon. Whether the parasitic dinoflagellates exhibit specificity in their infection is not well known, but this possibility has become an important issue in the development of biological control of harmful algal blooms. The 18S rDNA sequences from the parasite Amoebophrya sp. and its dinoflagellate host Dinophysis norvegica were determined and compared with the published sequence of Amoebophrya sp. infecting Gymnodinium sanguineum and other dinoflagellates. The results showed that the sequence from the parasite within D. norvegica was clustered with that of the one from G. sanguineum with 100% bootstrap support in a maximum-likelihood analysis. The observed identity between these two sequences was 93%, which indicates that they are not identical species. The two sequences from Amoebophrya sp. were deeply branched within the group of dinoflagellate sequences and represent the earliest diverging dinoflagellates. The sequence from the parasite Parvilucifera infectans, also infecting D. norvegica, was not closely related to the Amoebophrya sp. sequences. The sequence from D. norvegica appeared as a sister group to a cluster containing Prorocentrum lima and Alexandrium spp. without significant bootstrap support. The data presented herein support the hypothesis that A. ceratii comprises more than one species, and this opens the possibility that infections of harmful algal species might involve more than one Amoebophrya species.