Objectif UCYN-A is a globally abundant nitrogen fixing cyanobacterium with a very unusual metabolism and lifestyle. These microorganisms express nitrogenase genes with maximum transcript abundances during the light period (Zehr et al., 2007).Previous results in the group of Jonathan Zehr found that UCYN-A cyanobacteria are genetically incapable of oxygenic photosynthesis because the entire PSII apparatus is missing (although the PSI apparatus appears to be intact). Moreover, PSII isn´t the only component that is lacking in this genome: RuBisCo (ribulose-1,5 bisphosphate carboxylase-oxygenase that fixes CO2) and the tricarboxylic acid cycle (TCA) that usually are present in the cyanobacteria, are missing in UCYN-A.The lack of biosynthetic pathways suggested that this organism depend on other organisms, either in close association or in symbiosis, for critical nutrients.Thanks to flow cytometry and the metagenomic studies, this group obtained a complete genome sequence from UCYN-A and observed by quantitative isotopic analysis that UCYN-A has a symbiotic association with a unicellular Prymnesiophyte (Thompson et al., 2012).In this project we will determine whole-genome transcription over natural diel cycle in order to get a better understanding of the interplay of host and cyanobacterium metabolisms, and how it relates to supply of organic matter from the host eukaryote to the cyanobacterium.The transcriptome work will help to determine the global importance of N2 fixation by this cyanobacterial group in order to better constrain the global ocean nitrogen budget.- Thompson, A., R. Foster, A. Krupke, B. Carter, N. Musat, D. Vaulot, M. Kuypers & J.P. Zehr. Science 337:1546 (2012).- Zehr, J., S. Bench, B. Carter, I. Hewson, F. Niazi, T. Shi, H. Tripp & J. Affourtit. Science 322: 1110 (2008).- Zehr, J., J. Montoya, I. Hewson, E. Mondragon, C. Short, A. Hansen, B. Jenkins, M.Church & D.M. Karl. Limnol. Oceanogr. 52: 169 (2007). Champ scientifique natural sciencesbiological sciencesbiological behavioural sciencesethologybiological interactionsnatural sciencesbiological sciencesgeneticsgenomesnatural sciencesbiological sciencesmicrobiologynatural sciencesbiological sciencesbotany Programme(s) FP7-PEOPLE - Specific programme "People" implementing the Seventh Framework Programme of the European Community for research, technological development and demonstration activities (2007 to 2013) Thème(s) FP7-PEOPLE-2013-IOF - Marie Curie Action: "International Outgoing Fellowships for Career Development" Appel à propositions FP7-PEOPLE-2013-IOF Voir d’autres projets de cet appel Régime de financement MC-IOF - International Outgoing Fellowships (IOF) Coordinateur UNIVERSIDAD DE CORDOBA Contribution de l’UE € 254 474,10 Adresse AVENIDA DE MEDINA AZAHARA 5 14005 Cordoba Espagne Voir sur la carte Région Sur Andalucía Córdoba Type d’activité Higher or Secondary Education Establishments Contact administratif Carmen Tarradas Iglesias (Prof.) Liens Contacter l’organisation Opens in new window Site web Opens in new window Coût total Aucune donnée
