Aline D Batista1, Rinamara M Rosa1, Mariana Machado2, Alan S Magalhães1, Bárbara A Shalaguti1, Priscilla F Gomes1, Lidiane Covell1, Marcelo G M V Vaz1, Wagner L Araújo1,3, Adriano Nunes-Nesi4. 1. Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais, 36570-900, Brazil. 2. Instituto de Biociências, Universidade Federal de Goiás - Regional Jataí, Jataí, Goiás, 75801-615, Brazil. 3. Max-Planck Partner Group at the Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais, 36570-900, Brazil. 4. Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais, 36570-900, Brazil. nunesnesi@ufv.br.
Abstract
INTRODUCTION: The use of urea as a nitrogen (N) source by Chlorophytes usually enhances biomass and lipid production when compared to ammonium (NH4+). However, the metabolic shifts displayed by Chlamydomonas reinhardtii growing with this organic N source are not known. OBJECTIVES: This study aimed: (i) to characterize the metabolism of C. reinhardtii cultivated in media containing only urea as N source as well as combined with different NH4+ ratios; (ii) to understand how metabolism respond to urea availability. METHODS: Specific quantification of metabolites using 96-well microplates, and high-performance liquid chromatography combined with non-targeted metabolite profiling by gas chromatography (GC)-time-of-flight (TOF)-mass spectrometry (MS) were used in this study. In addition, GC analysis was used to determine fatty acid profiling. RESULTS: The use of urea did not alter the growth rate in comparison with NH4+. Interestingly, the cell number decreased and the cell size increased proportionally with urea availability. Furthermore, chlorophyll, protein and lipid contents increased with the amount of urea. Regarding the fatty acid profile, oleic acid (C18:1 w8) decreased with amount of urea, while linoleic acid (C18:2 w6) doubled in urea-containing medium. CONCLUSIONS: These results indicate that urea promotes remarkable adjustments in metabolism, without drastic changes in biomass, promoting changes in carbohydrate and amino acid metabolism, as well as in lipids production and fatty acid profile.
INTRODUCTION: The use of urea as a nitrogen (N) source by Chlorophytes usually enhances biomass and lipid production when compared to ammonium (NH4+). However, the metabolic shifts displayed by Chlamydomonas reinhardtii growing with this organic N source are not known. OBJECTIVES: This study aimed: (i) to characterize the metabolism of C. reinhardtii cultivated in media containing only urea as N source as well as combined with different NH4+ ratios; (ii) to understand how metabolism respond to urea availability. METHODS: Specific quantification of metabolites using 96-well microplates, and high-performance liquid chromatography combined with non-targeted metabolite profiling by gas chromatography (GC)-time-of-flight (TOF)-mass spectrometry (MS) were used in this study. In addition, GC analysis was used to determine fatty acid profiling. RESULTS: The use of urea did not alter the growth rate in comparison with NH4+. Interestingly, the cell number decreased and the cell size increased proportionally with urea availability. Furthermore, chlorophyll, protein and lipid contents increased with the amount of urea. Regarding the fatty acid profile, oleic acid (C18:1 w8) decreased with amount of urea, while linoleic acid (C18:2 w6) doubled in urea-containing medium. CONCLUSIONS: These results indicate that urea promotes remarkable adjustments in metabolism, without drastic changes in biomass, promoting changes in carbohydrate and amino acid metabolism, as well as in lipids production and fatty acid profile.
Authors: Gabriel O James; Charles H Hocart; Warwick Hillier; Hancai Chen; Farzaneh Kordbacheh; G Dean Price; Michael A Djordjevic Journal: Bioresour Technol Date: 2010-11-16 Impact factor: 9.642
Authors: Ian K Blaby; Anne G Glaesener; Tabea Mettler; Sorel T Fitz-Gibbon; Sean D Gallaher; Bensheng Liu; Nanette R Boyle; Janette Kropat; Mark Stitt; Shannon Johnson; Christoph Benning; Matteo Pellegrini; David Casero; Sabeeha S Merchant Journal: Plant Cell Date: 2013-11-26 Impact factor: 11.277