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+49 541 969 2656
amulkid @ uni-osnabrueck.de
Mulkidjanian, A.Y., E. V. Koonin, K. S. Makarova, S. L. Mekhedov, A. Sorokin, Y. I. Wolf, A. Dufresne, F. Partensky, H. Burd, D. Kaznadzey, R. Haselkorn, M. Y. Galperin 2006. The cyanobacterial genome core and the origin of photosynthesis, Proc. Natl. Acad. Sci. U.S.A., 103: 13126-13131. (Full text, pdf)
Mulkidjanian, A.Y., D.A. Cherepanov, and M.Y. Galperin. 2003. Survival of the fittest before the beginning of life: selection of the first oligonucleotide-like polymers by UV light. BMC. Evol. Biol 3:12 (freely accessible at http://www.biomedcentral.com/1471-2148/3/12)
We investigate the molecular mechanisms of biological energy conversion and their evolution. In our work, we combine biophysical and biochemical techniques with computational and evolutionary approaches. We concentrate on enzymes of phototrophic bacteria that are homologous (closely related) to the enzymes of mitochondria, the power stations of human cells. We exploit the bacterial photosynthetic apparatus to synchronously trigger the metabolic chains by flashes of light and then monitor the single turnovers of the enzymes involved. We use a set of spectrophotomertric and electrometric techniques that enable to trace subnanoscopic displacements of electric charges inside membrane proteins and at their surface. Routinely a resolution of up to 0.1 nm in space and up to 100 ns in time can be achieved for displacements of protons, electrons or charged protein groups. Via these charge displacements, we can follow the partial steps of enzyme catalysis. We complement our experimental research by kinetic modeling, electrostatic calculations and molecular dynamics simulations. The ultimate goal of our research is to obtain detailed mechanistic schemes for key energy converting enzymes, such as cytochrome bc1 complex, photosynthetic reaction centers, and ATP synthase.
Our methods allow us to probe the state of the membrane/water interfaces by tracing the proton passage across them.
By studying several enzymes simultaneously, we hope to understand the general "rules" of bioenergetic coupling.
We also use the tools of comparative genomics to explore the evolution of enzyme mechanisms.
In addition, we address the origin of life problem from the viewpoint of energetics.
Our research is being done in framework of a long-lasting collaboration between the University of Osnabrück and the Moscow State University.Here are the links to the topics of our studies: