Abstract
The terrestrial cyanobacterium Nostoc commune accumulates high levels of radioactive material, but the mechanism had not been understood. Localization of Sr and Cs in N. commune was analyzed by using the analytical scanning electron microscopy. N. commune was cultured in a chemically defined liquid medium supplemented with CsCl or SrCl2・6H2O. N. commune absorbed high amount of Sr and Cs, but the cultured monilioid cells were contracted. As a result of energy dispersive X-ray spectrometer analysis, Sr and Cs were detected in both cell and jelly-like extracellular matrix. These results suggested that N. commune absorbed Sr and Cs in both cell and extracellular matrix.
