The discovery of anammox bacteria in the 1990's has dramatically changed our understanding of the global nitrogen cycle. These bacteria perform ANaerobic AMMonium Oxidation (ANAMMOX), combining ammonium with nitrite into molecular dinitrogen (N2) and water, yielding energy for the cell. This process relies on highly unusual intermediates such as hydrazine. We are studying the molecular mechanism of the ANAMMOX process using structural biology.[more]
ACTIVITIES. Bruce Doak and his group invent and develop novel methods of sample delivery for use at advanced X-ray sources, including X-ray Free-Electron Lasers (XFEL) and fourth generation synchrotrons. Based on their research and development, they design and fabricate well-engineered sample injectors for X-ray scattering facilities worldwide.
Sunlight is an important environmental factor and light-induced chemical reactions may have both beneficial and detrimental biological effects. Photon absorption produces highly reactive excited molecules which can undergo chemical changes.
Giant viruses and virophages are two groups of DNA viruses that infect single-celled eukaryotes (protists). Encoding hundreds of proteins and featuring particles that are visible by light microscopy, giant viruses are the largest known viruses. Their enormous coding potential renders them host-independent for many biochemical pathways, such as transcription, glycosylation, DNA replication and repair, and allows certain giant viruses to replicate entirely in the cytoplasm. Virophages are smaller DNA viruses that parasitize upon the enzymatic complexity of giant viruses. In co-infected host populations, the virophage inhibits replication of the giant virus and increases host survival. We are interested in the underlying mechanisms of virophage-virus-host interactions and in the diversity and evolutionary history of these viruses.
Attaining a well defined three dimensional structure and thus functionality can be a serious challenge in the early life of many proteins. Although the final structure is energetically favored, many side reactions can occur mostly leading to aggregation that prevent the formation of the native protein structure. Molecular chaperones are ubiquitous in prokarytic/eukaryotic organisms and form cellular networks which assist protein folding in the cell.[more]
The very detailed behavioral and physiological analyses of our mice with altered GluA1 expression revealed, for the first time, that AMPA receptor plasticity is also critically involved in hippocampus-based learning and memory, thus illuminating the endogenous regulation of AMPA receptors. Several studies from us and our collaborators showed, with no doubt, that AMPA receptors with the GluA1 subunit are not essential for spatial reference memory - the gold standard for spatial learning -, but are critically involved in behavioral tasks for the spatial working memory; a learning deficiency which we could correlate with lack of some forms of long-term potentiation at CA3-to-CA1 hippocampal connections[more]