Oleg Sitsel
Aarhus University
Network
Latest external collaboration on country level. Dive into details by clicking on the dots.
Publication
Featured researches published by Oleg Sitsel.
Journal of Synchrotron Radiation | 2015
Karol Nass; Lutz Foucar; Thomas R. M. Barends; Elisabeth Hartmann; Sabine Botha; Robert L. Shoeman; R. Bruce Doak; Roberto Alonso-Mori; Andrew Aquila; Sasa Bajt; Anton Barty; Richard Bean; Kenneth R. Beyerlein; Maike Bublitz; Nikolaj D. Drachmann; Jonas Lindholt Gregersen; H. Olof Jönsson; Wolfgang Kabsch; Stephan Kassemeyer; Jason E. Koglin; Michael Krumrey; Daniel Mattle; Marc Messerschmidt; Poul Nissen; Linda Reinhard; Oleg Sitsel; Dimosthenis Sokaras; Garth J. Williams; Stefan P. Hau-Riege; Nicusor Timneanu
Proteins that contain metal cofactors are expected to be highly radiation sensitive since the degree of X-ray absorption correlates with the presence of high-atomic-number elements and X-ray energy. To explore the effects of local damage in serial femtosecond crystallography (SFX), Clostridium ferredoxin was used as a model system. The protein contains two [4Fe-4S] clusters that serve as sensitive probes for radiation-induced electronic and structural changes. High-dose room-temperature SFX datasets were collected at the Linac Coherent Light Source of ferredoxin microcrystals. Difference electron density maps calculated from high-dose SFX and synchrotron data show peaks at the iron positions of the clusters, indicative of decrease of atomic scattering factors due to ionization. The electron density of the two [4Fe-4S] clusters differs in the FEL data, but not in the synchrotron data. Since the clusters differ in their detailed architecture, this observation is suggestive of an influence of the molecular bonding and geometry on the atomic displacement dynamics following initial photoionization. The experiments are complemented by plasma code calculations.
Biochemistry | 2015
Oleg Sitsel; Christina Grønberg; Henriette Elisabeth Autzen; Kaituo Wang; Gabriele Meloni; Poul Nissen; Pontus Gourdon
Copper and zinc are micronutrients essential for the function of many enzymes while also being toxic at elevated concentrations. Cu(I)- and Zn(II)-transporting P-type ATPases of subclass 1B are of key importance for the homeostasis of these transition metals, allowing ion transport across cellular membranes at the expense of ATP. Recent biochemical studies and crystal structures have significantly improved our understanding of the transport mechanisms of these proteins, but many details about their structure and function remain elusive. Here we compare the Cu(I)- and Zn(II)-ATPases, scrutinizing the molecular differences that allow transport of these two distinct metal types, and discuss possible future directions of research in the field.
EMBO Reports | 2015
Daniel Mattle; Limei Zhang; Oleg Sitsel; Lotte Thue Pedersen; Maria Rosa Moncelli; Francesco Tadini-Buoninsegni; Pontus Gourdon; Douglas C. Rees; Poul Nissen; Gabriele Meloni
Cells regulate copper levels tightly to balance the biogenesis and integrity of copper centers in vital enzymes against toxic levels of copper. PIB‐type Cu+‐ATPases play a central role in copper homeostasis by catalyzing the selective translocation of Cu+ across cellular membranes. Crystal structures of a copper‐free Cu+‐ATPase are available, but the mechanism of Cu+ recognition, binding, and translocation remains elusive. Through X‐ray absorption spectroscopy, ATPase activity assays, and charge transfer measurements on solid‐supported membranes using wild‐type and mutant forms of the Legionella pneumophila Cu+‐ATPase (LpCopA), we identify a sulfur‐lined metal transport pathway. Structural analysis indicates that Cu+ is bound at a high‐affinity transmembrane‐binding site in a trigonal‐planar coordination with the Cys residues of the conserved CPC motif of transmembrane segment 4 (C382 and C384) and the conserved Met residue of transmembrane segment 6 (M717 of the MXXXS motif). These residues are also essential for transport. Additionally, the studies indicate essential roles of other conserved intramembranous polar residues in facilitating copper binding to the high‐affinity site and subsequent release through the exit pathway.
IUCrJ | 2015
Maike Bublitz; Karol Nass; N.D. Drachmann; Anders J. Markvardsen; Matthias J. Gutmann; Thomas R. M. Barends; Daniel Mattle; Robert L. Shoeman; R.B. Doak; Sébastien Boutet; Marc Messerschmidt; M. Marvin Seibert; Garth J. Williams; Lutz Foucar; Linda Reinhard; Oleg Sitsel; J.L. Gregersen; Johannes D. Clausen; Thomas Boesen; Kamil Gotfryd; K.-T. Wang; Claus Olesen; Jesper V. Møller; Poul Nissen; Ilme Schlichting
The structure determination of P-type ATPase–ligand complexes from microcrystals by serial femtosecond crystallography using a free-electron laser is described. The feasibility of the method for ligand screening is demonstrated, and SFX data quality metrics as well as suitable refinement procedures are discussed.
Methods of Molecular Biology | 2016
Xiangyu Liu; Oleg Sitsel; Kaituo Wang; Pontus Gourdon
Understanding of the functions and mechanisms of fundamental processes in the cell requires structural information. Structural studies of membrane proteins typically necessitate large amounts of purified and preferably homogenous target protein. Here, we describe a rapid overproduction and purification strategy of a bacterial PIB-type ATPase for isolation of milligrams of target protein per liter Escherichia coli cell culture, with a final quality of the sample which is sufficient for generating high-resolution crystals.
Nature Structural & Molecular Biology | 2014
Magnus Andersson; Daniel Mattle; Oleg Sitsel; Tetyana Klymchuk; Anna Marie Nielsen; Lisbeth Birk Møller; Stephen H. White; Poul Nissen; Pontus Gourdon
Nature | 2014
Kaituo Wang; Oleg Sitsel; Gabriele Meloni; Henriette Elisabeth Autzen; Magnus Andersson; Tetyana Klymchuk; Anna Marie Nielsen; Douglas C. Rees; Poul Nissen; Pontus Gourdon
Journal of Molecular Biology | 2013
Daniel Mattle; Oleg Sitsel; Henriette Elisabeth Autzen; Gabriele Meloni; Pontus Gourdon; Poul Nissen
Biophysical Journal | 2016
Christina Grønberg; Oleg Sitsel; Erik Lindahl; Pontus Gourdon; Magnus Andersson
Methods of Molecular Biology | 2016
Oleg Sitsel; Kaituo Wang; Xiangyu Liu; Pontus Gourdon