Mami Konomi

New Preparation Method using Ionic Liquid for Fast and Reliable SEM Observation of Biological Specimens

1. Tokyo Solution Lab., Hitachi High-Technologies Corp., KANAGAWA SCIENCEPARK, R&D BUSINESSPARK BLDG C-1F, 3-2-1, Sakado, Takatsu, Kawasaki, Kanagawa 213-0012, Japan 2. Hitachi High-Technologies Corp., 882, ichige, hitachinaka, Ibaraki 312-8504, Japan 3. Miyoshi Oil & Fat CO., LTD. 4-66-1, Horikiri, Katushika, Tokyo 124-0006, Japan 4. Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871 Japan

Deciphering the relationship among phosphate dynamics, electron-dense body and lipid accumulation in the green alga Parachlorella kessleri

Phosphorus is an essential element for life on earth and is also important for modern agriculture, which is dependent on inorganic fertilizers from phosphate rock. Polyphosphate is a biological polymer of phosphate residues, which is accumulated in organisms during the biological wastewater treatment process to enhance biological phosphorus removal. Here, we investigated the relationship between polyphosphate accumulation and electron-dense bodies in the green alga Parachlorella kessleri. Under sulfur-depleted conditions, in which some symporter genes were upregulated, while others were downregulated, total phosphate accumulation increased in the early stage of culture compared to that under sulfur-replete conditions. The P signal was detected only in dense bodies by energy dispersive X-ray analysis. Transmission electron microscopy revealed marked ultrastructural variations in dense bodies with and without polyphosphate. Our findings suggest that the dense body is a site of polyphosphate accumulation, and P. kessleri has potential as a phosphate-accumulating organism.

Ionic Liquid Preparation for SEM Observation of Minute Crustacean

1. Tokyo Solution Lab., Hitachi High-Technologies Corp., KANAGAWA SCIENCEPARK, R&D BUSINESSPARK BLDG C-1F, 3-2-1, Sakado, Takatsu, Kawasaki, Kanagawa 213-0012, Japan 2. Hitachi High-Technologies Corp., 882, ichige, hitachinaka, Ibaraki 312-8504, Japan 3. Miyoshi Oil & Fat CO.,LTD. 4-66-1, Horikiri, Katushika, Tokyo 124-0006, Japan 4. Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871 Japan