caa a22 4500 605455309 CHVBK 20210128100211.0 cr unu---uuuuu 210128e20151201xx s 000 0 eng 10.1007/s10872-015-0310-8 doi (NATIONALLICENCE)springer-10.1007/s10872-015-0310-8 New radioisotope-free method for measuring bacterial production using [15N5]-2′-deoxyadenosine and liquid chromatography mass spectrometry (LC-MS) in aquatic environments [Elektronische Daten] [Kenji Tsuchiya, Tomoharu Sano, Nobuyuki Kawasaki, Hideki Fukuda, Noriko Tomioka, Koji Hamasaki, Yuya Tada, Shinji Shimode, Tatsuki Toda, Akio Imai] This study proposed a non-radioactive quantitative measurement of bacterial production using stable isotope nitrogen-15-labeled deoxyadenosine ([15N5]-2′-deoxyadenosine; 15N-dA) by liquid chromatography mass spectrometry (LC-MS). The method of preparing 5N-dA described in this study included incubation of seawater or lake water with 15N-dA for 5-24h, filtration onto a membrane filter, DNA extraction, enzymatic hydrolysis of DNA to nucleosides and quantification of 15N-dA by LC-MS. In the DNA extraction, the silica beads method was examined first, but a large amount of salts and enzymatic inhibitors used in the method caused failure of subsequent procedures, such as enzymatic hydrolysis and LC-MS analysis. On the other hand, the magnetic beads method showed much better results for the extraction. The incorporation rate of 15N-dA was significantly positively correlated to that of tritium-labeled thymidine (3H-TdR) in samples of coastal seawaters and lake waters. The average 15N-dA: 3H-TdR incorporation ratio for the seawater sample was 0.55 with 2.5 and 97.5% confidence intervals of 0.51 and 0.58, respectively; the average ratio for the lake water sample was 0.28 with 2.5 and 97.5% confidence intervals of 0.23 and 0.34, respectively. The results suggest that the 15N-dA method can be applied to the measurement of bacterial production in aquatic ecosystems, and that this method can accurately predict the DNA synthesis rates measured by the conventional method. The Oceanographic Society of Japan and Springer Japan, 2015 Bacterial production nationallicence Stable isotope nationallicence Liquid chromatography mass spectrometry (LC-MS) nationallicence DNA synthesis nationallicence 2′-deoxyadenosine nationallicence Tsuchiya Kenji Faculty of Science and Engineering, Soka University, 1-236, Tangi-machi, 192-8577, Hachioji, Tokyo, Japan aut Sano Tomoharu National Institute for Environmental Studies, 16-2, Onogawa, 305-8506, Tsukuba, Ibaraki, Japan aut Kawasaki Nobuyuki National Institute for Environmental Studies, 16-2, Onogawa, 305-8506, Tsukuba, Ibaraki, Japan aut Fukuda Hideki Atmosphere and Ocean Research Institute, The University of Tokyo, 5-1-5, Kashiwanoha, 277-8564, Kashiwa, Chiba, Japan aut Tomioka Noriko National Institute for Environmental Studies, 16-2, Onogawa, 305-8506, Tsukuba, Ibaraki, Japan aut Hamasaki Koji Atmosphere and Ocean Research Institute, The University of Tokyo, 5-1-5, Kashiwanoha, 277-8564, Kashiwa, Chiba, Japan aut Tada Yuya Atmosphere and Ocean Research Institute, The University of Tokyo, 5-1-5, Kashiwanoha, 277-8564, Kashiwa, Chiba, Japan aut Shimode Shinji Graduate School of Environment and Information Science, Yokohama National University, 79-7 Tokiwadai, Hodogaya-ku, 240-8501, Yokohama, Kanagawa, Japan aut Toda Tatsuki Faculty of Science and Engineering, Soka University, 1-236, Tangi-machi, 192-8577, Hachioji, Tokyo, Japan aut Imai Akio National Institute for Environmental Studies, 16-2, Onogawa, 305-8506, Tsukuba, Ibaraki, Japan aut Journal of Oceanography Springer Japan 71/6(2015-12-01), 675-683 0916-8370 71:6<675 2015 71 10872 https://doi.org/10.1007/s10872-015-0310-8 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s10872-015-0310-8 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Tsuchiya Kenji Faculty of Science and Engineering, Soka University, 1-236, Tangi-machi, 192-8577, Hachioji, Tokyo, Japan aut NATIONALLICENCE 700 1- Sano Tomoharu National Institute for Environmental Studies, 16-2, Onogawa, 305-8506, Tsukuba, Ibaraki, Japan aut NATIONALLICENCE 700 1- Kawasaki Nobuyuki National Institute for Environmental Studies, 16-2, Onogawa, 305-8506, Tsukuba, Ibaraki, Japan aut NATIONALLICENCE 700 1- Fukuda Hideki Atmosphere and Ocean Research Institute, The University of Tokyo, 5-1-5, Kashiwanoha, 277-8564, Kashiwa, Chiba, Japan aut NATIONALLICENCE 700 1- Tomioka Noriko National Institute for Environmental Studies, 16-2, Onogawa, 305-8506, Tsukuba, Ibaraki, Japan aut NATIONALLICENCE 700 1- Hamasaki Koji Atmosphere and Ocean Research Institute, The University of Tokyo, 5-1-5, Kashiwanoha, 277-8564, Kashiwa, Chiba, Japan aut NATIONALLICENCE 700 1- Tada Yuya Atmosphere and Ocean Research Institute, The University of Tokyo, 5-1-5, Kashiwanoha, 277-8564, Kashiwa, Chiba, Japan aut NATIONALLICENCE 700 1- Shimode Shinji Graduate School of Environment and Information Science, Yokohama National University, 79-7 Tokiwadai, Hodogaya-ku, 240-8501, Yokohama, Kanagawa, Japan aut NATIONALLICENCE 700 1- Toda Tatsuki Faculty of Science and Engineering, Soka University, 1-236, Tangi-machi, 192-8577, Hachioji, Tokyo, Japan aut NATIONALLICENCE 700 1- Imai Akio National Institute for Environmental Studies, 16-2, Onogawa, 305-8506, Tsukuba, Ibaraki, Japan aut NATIONALLICENCE 773 0- Journal of Oceanography Springer Japan 71/6(2015-12-01), 675-683 0916-8370 71:6<675 2015 71 10872