caa a22 4500 37894147X CHVBK 20180305123653.0 cr unu---uuuuu 161128e20040712xx s 000 0 eng 10.1515/BOT.2004.026 doi (NATIONALLICENCE)gruyter-10.1515/BOT.2004.026 Short-term uptake of dissolved organic nitrogen by an axenic strain of Ulva pertusa (Chlorophyceae) using [15]N isotope measurements [Elektronische Daten] [Kenji Tarutani, Yoko Niimura, Takuji Uchida] Uptake rates of dissolved organic nitrogen (DON; urea, alanine and glutamate) by Ulva pertusa were determined using axenic cultures and 15N isotopic tracers. When urea or alanine was added to N-starved cultures, the incorporation of 15N into algal tissue was found at all concentrations tested (0.5-40 μM). Maximum uptake rates were 7.92 and 3.00 μmol N g−1 dw h−1, and half-saturation constants were 25.5 and 27.6 μM for urea and alanine, respectively. These results show that U. pertusa can take up urea and alanine directly without bacterial decomposition to inorganic nitrogen. Therefore, U. pertusa is able to utilize certain species of DON, and has the potential to regulate DON fluxes and transformations in coastal environments. Copyright © 2004 by Walter de Gruyter GmbH & Co. KG Hydrobiology nationallicence Mycology, fungi nationallicence Botany & plant sciences nationallicence Tarutani Kenji aut Niimura Yoko aut Uchida Takuji aut Botanica Marina Walter de Gruyter 47/3(2004-07-12), 248-250 0006-8055 47:3<248 2004 47 botm https://doi.org/10.1515/BOT.2004.026 text/html Onlinezugriff via DOI 1 research article jats NATIONALLICENCE 856 40 https://doi.org/10.1515/BOT.2004.026 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Tarutani Kenji aut NATIONALLICENCE 700 1- Niimura Yoko aut NATIONALLICENCE 700 1- Uchida Takuji aut NATIONALLICENCE 773 0- Botanica Marina Walter de Gruyter 47/3(2004-07-12), 248-250 0006-8055 47:3<248 2004 47 botm CC0 http://creativecommons.org/publicdomain/zero/1.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-gruyter