Study on sustainable formation of actinide phosphates in microbial food chain

2015 Fiscal Year Final Research Report

• Project/Area Number: 25420910
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Nuclear engineering
• Research Institution: Japan Atomic Energy Agency
• Principal Investigator: Kozai Naofumi 国立研究開発法人日本原子力研究開発機構, 原子力科学研究部門 先端基礎研究センター, 研究主幹 (80354877)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: ゾウリムシ / 酵母 / ウラン / 食物連鎖 / リン酸塩 / 疑似コロイド / 表面タンパク質

Outline of Final Research Achievements

When Paramecium eats yeast cells on which heavy elements such as uranium were fixed as phosphate mineral, the heavy element phosphates were excreted from Paramecium, mostly undissolved, and migrated into membrane-like precipitates in which digestion residues of yeast cells were connected with each other by dense organic substances. We found that Paramecium has an ability to reduce adsorption of heavy elements on cells through the process where heavy elements are adsorbed to the soluble huge glycoproteins on Paramecium cell surfaces and subsequently the glycoproteins are dissolved into aqueous phase. These glycoproteins are easily polymerized in aqueous phase. These results show heavy elements are transformed to pseudocolloid by Paramecium and also suggest that the membrane-like precipitates may be formed with the glycoprotein binding digestion residues of yeast cells.

Free Research Field

放射性廃棄物地層処分