Crassostrea gigas ferritin: cDNA sequence analysis for two heavy chain type subunits and protein purification.

Ferritin has been shown as being the principal iron storage in the majority of living organisms. In marine species, ferritin is also involved in high-level accumulation of (210)Po. As part of our work on the investigation of these radionuclides' concentration in natural environment, ferritin was searched at the gene and protein level.

Identification of 137Cs-and 241Am-binding sites in the oyster Crassostrea gigas.

The subcellular distribution and binding of 241Am and 137Cs in the visceral mass of the oyster Crassostrea gigas were investigated following exposure to sea water contaminated with these radionuclides. 241Am was predominantly sequestered by the lysosomal system. Approximately, 10% of 241Am was associated with soluble macromolecules.

Binding of 241Am to carp cytosolic fractions in vitro.

Recent studies on the competition between Cd and radionuclides have been reported in marine species. The present investigation aims to study the binding of 241Am to freshwater fish cytosolic fraction before and after Cd-treatment. The main organs studied are the liver, kidneys and muscles.

Biodynamic study of americium-241 accumulation in the cytosol of the hepatopancreas of the lobster Homarus gammarus.

In the lobster, most of the radionuclides ingested with contaminated food are concentrated in the digestive gland. Americium-241 accumulation in the hepatopancreas of the lobster was studied during the digestive cycle. Fractionations of cytosols at different times after ingestion of radioactive preys were performed by gel permeation chromatography to determine the distribution of 241Am in the different macromolecular components.

Chemical behaviour of three radionuclides (cesium, americium and technetium) and their uptake at the cytosolic level in aquatic organisms.

In previous papers, we observed that there were great differences in the subcellular accumulation and elimination of 137Cs, 99Tc and 241Am in different marine animals. In this study, we analysed and compared the behaviour of these radionuclides at the cytosolic level. We found great similarities in the cytosolic distribution of a given radionuclide in the various organisms studied.

Distribution of [241Am] in hepato-pancreatic nuclear proteins of the lobster (Homarus gammarus).

Recent studies on the bio-accumulation of transuranic elements in marine invertebrates have demonstrated an intracellular concentration of radionuclides in the digestive gland. The present investigation aims to establish the distribution of [241Am] within the different structures of the cell nucleus. Lobsters were experimentally contaminated through feeding and then killed.

Conditions for the extraction of protease-free LMG proteins from calf thymus.

Calf thymus LMG proteins are known to be susceptible to a wide variety of chromatin-associated proteases. We have investigated the use of different inhibitors to protect LMG chromosomal proteins from proteolytic degradation. In this work we have developed a preparative method for the extraction of LMG proteins from purified chromatin which provides an LMG protein extract devoid of proteolytic activity.