Meddelelser KEMISK INSTITUT MOLEKYLER DER SAMLER SIG I AVANCEREDE NANOSTRUKTURER - HVORFOR OG HVORDAN?

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1 Index for nr. 32 S 259 Ph.D. forsvar: Grethe Vestergaard Jensen S 260 Ph.D. forsvar: Kasper Kristensen S 261 Kandidatårseksamen: Sidsel Dahl Schrøder S 262 Kandidatårseksamen: Anja Funch Brøgger S 263 Studenterkollokvium: Mikkel Vindbæk Andersen S 264 Scientific Talk: Dr. Stephan Bachmann S 265 inano Lecture: Professor, Dr. Stefan U. Egelhaaf S 266 inano Lecture: Professor, Dr. Hellmut Eckert S 267 Specialized inano Lecture: Dr. Jörg H. Kleinschmidt S 268 Kjeldgaard Lecture: Ingrid Grummt

2 Meddelelser KEMISK INSTITUT 43. årgang nr. 32 AARHUS UNIVERSITET 13. oktober 2011 olekyler der samler sig i avancerede nanostrukturer - Hvorfor... MOLEKYLER DER SAMLER SIG I AVANCEREDE NANOSTRUKTURER - HVORFOR OG HVORDAN? Ph.d.-forsvar, fredag den 14. oktober Cand.scient. Grethe Vestergaard Jensen. I løbet af sit ph.d.-studium har Grethe Vestergaard Jensen forsket i molekyler, der er 'programmeret', så de samler sig i veldefinerede strukturer. Dette gælder f.eks. for sæbemolekyler og større molekyler sammensat af to forskellige polymerblokke. I vand danner disse molekyler små aggregater kaldet miceller, der kan have et væld af forskellige størrelser og former (runde, aflange, flade) afhængigt af molekylernes kemiske struktur. De har mange forskellige anvendelser som tensider, stabilisatorer og emulgatorer, både inden for rengøring, personlig pleje, i olieindustrien, fødevarer og i medicin RIKKE J. LJUNGMANN I afhandlingen vises det, hvordan micellernes struktur kan bestemmes ved hjælp af spredning af røntgenstråling. For at forstå hvad der er afgørende for, hvilken struktur der dannes, sammenlignes resultaterne med forskellige teoretiske forudsigelser. Når der tilsættes salt, eller når opløsningerne blandes med andre sæbemolekyler, kan micellerne ændre form, eller nye miceller kan dannes. Dette forgår meget hurtigt, i løbet af brøkdele af et sekund. Ved brug af høj-intensiv røntgenstråling fra en synkrotronkilde, kan ændringerne følges. Dette har givet ny viden om de molekylære mekanismer, der er involveret i dannelsen af miceller. Twitter Facebook Synes godt om Ph.d.-studiet er gennemført ved Interdisciplinært Nanoscience Center, inano, under Science and Technology ved Aarhus Universitet. Grethe Vestergaard Jensen Tid: Fredag den 14. oktober 2011 kl Sted: Auditorium D2, Institut for Matematik, Aarhus Universitet Afhandlingens titel: Scattering Studies of Micelles in Solution. Structure, Formation, and Rearrangement of Micelles Kontaktinfo: Grethe Vestergaard Jensen, inagvj@inano.au.dk Bedømmelsesudvalg: Professor, Dr. Stefan Egelhaaf, Lehrstuhl für Physik der weichen Materie, Heinrich-Heine-Universität, Düsseldorf, Tyskland Professor Kell Mortensen, Head of Biophysics Group, Department of Natural Sciences, Faculty of Life Sciences, Københavns Universitet Professor Niels Chr. Nielsen (formand), inano og Institut for Kemi, Aarhus Universitet Hovedvejleder: Professor Jan Skov Pedersen, inano og Institut for Kemi, Aarhus Universitet Sprog: Ph.d.-afhandlingen forsvares på engelsk. Forsvaret er offentligt. Afhandlingen ligger til gennemsyn hos Graduate School of Science and Technology, GSST, Ny Munkegade 120, bygning 1521, lokale 112. Ph. D. Forsvar Forskellige geometrier af molekylerne giver forskellige nanostrukturer

3 HIGH-ACCURACY COMPUTER CALCULATIONS ON LARGE MOLECULES PhD defence, Friday 21 October Kasper Kristensen ANNE HAVE LIETZEN Computer calculations on molecules often supplement experimental studies and may to some extent also replace expensive or potentially dangerous experiments. The main challenge for traditional high-accuracy methods is that the time for a calculation increases dramatically with system size (for example, a high-precision calculation of insulin would take several million years!). This makes it impossible to carry out accurate theoretical studies of, for example, large biological molecules with potential applications in the pharmaceutical industry i.e. how a drug binds to a protein. Twitter Facebook Synes godt om During his PhD studies, Kasper Kristensen investigated how high-accuracy quantum mechanical models can be reformulated to make them applicable to large molecules (e.g. proteins). The basic formulations have been implemented, thereby providing the foundation for future high-accuracy theoretical studies of biological molecules, for example. Kasper Kristensen Time: Friday 21 October 2011 at Place: Lecture Theatre VI, building 1510, room 213 Title of dissertation: Self-Consistent Field Response Theory and Coupled-Cluster Theory Contact information: Kasper Kristensen, kasperk@chem.au.dk Members of the assessment committee: Professor Hans-Joachim Werner, University of Stuttgart, Germany Professor Jack Simons, University of Utah, USA Associate Professor Ove Christensen, Department of Chemistry, Aarhus University Supervisor: Professor Poul Jørgensen, Department of Chemistry, Aarhus University Language: The dissertation will be defended in English The defence is public. The dissertation is available for reading at the Graduate School of Science and Technology / GSST, Ny Munkegade 120, building 1521, room 112. Ph. D. Forsvar Illustration of insulin. To describe a molecule of this size, it is necessary to describe local physical effects without having to consider the whole molecule. The core of the project is to do this using local functions, such as the yellow/green mushroom in the left part of the image. COMMENTS ON CONTENT: IDA MARIE GERDES REVISED Science and Technology mail@science.au.dk CVR no: Contact web editor Aarhus University Tel: P no: Ny Munkegade 120 Fax: EAN no: DK-8000 Aarhus C Budget code: Denmark

4 O P S L A G NATURVIDENSKABELIG KANDIDATEKSAMEN SOMMER 2011 KEMI Kandidatårseksamen: Sidsel Dahl Schrøder Mundtlig eksamen: Torsdag den , kl Eksamen afholdes: Aud. I

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6 Studenterkollokvium Mikkel Vindbæk Andersen: Li-ion Batterier: funktion, materialer og ydeevne Tirsdag d. 18/ , Kl:11:15 i Aud. VI Abstrakt: Genopladelige Li-ion batterier har, siden de første gang blev demonstreret i 1979 af John B. Goodenough, indtaget en større og større plads i vores samfund. Der findes flere forskellige elektrode materialer og elektrolytter, som påvirker stabiliteten, ydeevnen og prisen på Li-ion batterier. Desuden har episoder de seneste år vist, at sikkerheden også er et meget vigtigt aspekt for udviklingen af moderne Li-ion batterier. Foredraget vil gennemgå en række interessante elektrode og elektrolyt materialer, sikkerheden af disse, samt give en ide om hvad fremtiden kan bringe inden for Li-ion batterier. Alle er velkomne.

7 US AARH SCIENTIFIC TALK Catalysis as a Key Technology for the Synthesis of APIs and Building Blocks by Dr. Stephan Bachmann F. Hoffmann-La Roche AG Process Research & Synthesis Switzerland Friday October 14 th, 2011 at in Aud. 1 (Department of Chemistry, build ) INSTITUT FOR KEMI SCIENCE AND TECHNOLOGY AARHUS UNIVERSITET

8 inano lecture of the week - open to all Professor, Dr. Stefan U. Egelhaaf Department of Physics of Soft Matter International Helmholtz Research School on Biophysics and Soft Matter Heinrich-Heine-Universität Düsseldorf, Germany Title: Time: Location: Flow into and through nanoporous matrices - neutron imaging experiments Friday 14 October 2011, at 10:15am Coffee and bread will be served from 10am Phys Aud, 3 rd floor, Department of Physics Abstract: Flow or diffusion of solvent into and through soft and complex matter matrices is not only of fundamental interest but also important for applications ranging from drug delivery to food packaging. Recently it became possible to investigate such processes in situ due to significant technical improvements in neutron imaging. Its spatial and temporal resolution (a few tens of micrometers and seconds) as well as its ability to penetrate most matrices, allows us to quantitatively follow the evolution of concentration profiles even within the matrices. We have explored this technique for a variety of systems, including the imbibition of solvent into nanoporous Vycor glass, the influx of solvent into semi-crystalline polymers and (macroporous) hydrogels, the dissolution of amphiphiles upon contact with water, and the swelling of biologically-relevant lipid lamellar phases.

9 inano lecture of the week - open to all Professor, Dr. Hellmut Eckert Institut für Physikalische Chemie Westfalhlische Wilhelms-Universität Münster, Germany Title: Time: New Magnetic Resonance Approaches Towards the Structural Characterization of Luminescent Ceramic Materials Friday 21 October 2011, at 10:15am Coffee and bread will be served from 10am Location: Aud I, Department of Chemistry ( ) Abstract: Glasses and vitroceramics based have been introduced as excellent alternatives to single crystalline host materials for luminescent rare-earth ions with special laser applications. To optimize the luminescent properties of these materials, detailed structural information regarding the local environment of the rare-earth species is essential. This characterization must include the distribution of the rare earth ions over the different crystalline and amorphous components present. While solid state nuclear magnetic resonance (NMR) is in general a promising tool for such purposes, unfortunately, the rare-earth ions themselves cannot be studied by NMR due to their paramagnetism. To overcome this difficulty, we have developed a comprehensive examination strategy consisting of (a) the use of diamagnetic mimics such as 45 Sc and 89 Y NMR [1], (b) the quantification of paramagnetic broadening effects imparted by the rare-earth ions upon the solid state NMR spectra of framework atoms [2], and (c) the direct study of electron-nuclear interactions as probed by electron spin echo envelope modulation (ESEEM) spectroscopy [3]. Results will be presented for a range of rare-earth containing aluminoborate and phosphate glasses and ceramics, and extensions to other laser ceramic systems will be discussed. References: [1] H. Deters, H.; A. S. S. de Camargo, C. N. Santos, C. R. Ferrari, A. C. Hernandes, A. Ibanez, M. T. Rinke, H. Eckert, J. Phys. Chem. C 113, (2009). [2] H. Deters, A. S. S. de Camargo, C. N. Santos, H. Eckert, J. Phys. Chem. C 114, (2010). [3] H. Deters, J. F. de Lima, C. J. Magon, A. S. S. de Camargo, H. Eckert, Phys. Chem. Chem. Phys. 2011, in press.

10 Specialized inano lecture - open to all Dr Jörg H. Kleinschmidt Department of Biology University of Konstanz Konstanz, Germany Title: Role of folding factors from the periplasm of E.coli in insertion and folding of a β-barrel membrane protein into lipid bilayers. Time: Monday 24 October 2011, at 11:15 Location: , Department of Physics Abstract: Folding and insertion of outer membrane proteins (OMPs) of Gram-negative bacteria are not well understood. Biosynthesized in the cytosol, OMPs are translocated via the SecYEG translocon across the plasma membrane into the periplasm, where the leader peptidase cleaves their signal sequence. The subsequent transport and insertion into the outer membrane (OM) are mediated by several folding factors. Once inserted into the OM, the transmembrane domains of most OMPs form highly stable β-barrel structures, composed of an even number of β-strands, ranging from 8 to 24. Several proteins have been isolated from the periplasm, which prevent aggregation of unfolded OMPs in aqueous solution and in the periplasm. Depletion of these molecular chaperones in cells leads to lower concentrations of the OMPs in the OM, indicating that chaperones are important for OMP transport and/or OMP insertion. However, the periplasmic chaperones are not essential for cell survival. In contrast, the β-barrel assembly machinery complex (BAM-complex), which is part of the OM, is essential for OMP assembly and OM-biogenesis. For the outer membrane protein A as a client OMP, I present biophysical data for the roles of the periplasmic chaperones Skp, FkpA, and SurA and for the role of the core protein of the BAM complex, BamA.

11 A KJELDGAARD LECTURE Friday 14 October 2011 at am Bartholin Aud I, Bldg. 1241, Room135 PhD session: Bartholin Bldg.1241, Room 211 A Kjeldgaard Lecture in Molecular Biology Ingrid Grummt German Cancer Research Center Heidelberg, Germany Non-coding RNA targets chromatin modifying enzymes to regulatory gene sequences Transcriptional regulation of rrna genes (rdna) is brought about by both modification of RNA polymerase I-specific transcription factors and by epigenetic mechanisms. Epigenetic silencing of a subpopulation of rdna requires prna, processed nt noncoding RNA that originates from the intergenic spacer and overlaps with the rdna promoter. Overexpression of prna mediates de novo DNA methylation and transcriptional repression, whereas antisense-mediated depletion of prna decreases rdna methylation. A 20 nt sequence in the 5 -terminal part of prna forms a DNA:RNA triplex with a transcription factor binding site, and this triplex structure is specifically recognized by the DNA methyltransferase DNMT3b. The results reveal a compelling RNA-based strategy for epigenetic programming, and imply that ncrnas may guide DNA methyltransferase to specific genomic sites to methylate DNA. In addition, rdna is also transcribed in antisense orientation, yielding a heterogeneous population of long RNA polymerase II-directed transcripts that cover the rdna promoter and the pre-rrna coding region. The level of antisense RNA is increased in serum-starved and density-arrested cells. Up-regulation of antisense transcripts correlates with enhanced recruitment of the methyltransferase Suv4-20 to rdna, increased trimethylation of H4K20 and inhibition of transcription. The results indicate that the specific interaction of Suv4-20 with antisense RNA is required to trigger H4K20 trimethylation and chromatin compaction at the rdna promoter in response to growth factor deprivation. The lecture will be followed by sandwich lunch and a chalk-board session for PhD students The Kjeldgaard Lecture Series is organised by AU DEPT. OF MOLECULAR BIOLOGY AND GENETICS AARHUS UNIVERSITY