TY  - JOUR
A1  - Kubin, Markus
A1  - Kern, Jan
A1  - Gul, Sheraz
A1  - Kroll, Thomas
A1  - Chatterjee, Ruchira
A1  - Loechel, Heike
A1  - Fuller, Franklin D.
A1  - Sierra, Raymond G.
A1  - Quevedo, Wilson
A1  - Weniger, Christian
A1  - Rehanek, Jens
A1  - Firsov, Anatoly
A1  - Laksmono, Hartawan
A1  - Weninger, Clemens
A1  - Alonso-Mori, Roberto
A1  - Nordlund, Dennis L.
A1  - Lassalle-Kaiser, Benedikt
A1  - Glownia, James M.
A1  - Krzywinski, Jacek
A1  - Moeller, Stefan
A1  - Turner, Joshua J.
A1  - Minitti, Michael P.
A1  - Dakovski, Georgi L.
A1  - Koroidov, Sergey
A1  - Kawde, Anurag
A1  - Kanady, Jacob S.
A1  - Tsui, Emily Y.
A1  - Suseno, Sandy
A1  - Han, Zhiji
A1  - Hill, Ethan
A1  - Taguchi, Taketo
A1  - Borovik, Andrew S.
A1  - Agapie, Theodor
A1  - Messinger, Johannes
A1  - Erko, Alexei
A1  - Föhlisch, Alexander
A1  - Bergmann, Uwe
A1  - Mitzner, Rolf
A1  - Yachandra, Vittal K.
A1  - Yano, Junko
A1  - Wernet, Philippe
T1  - Soft x-ray absorption spectroscopy of metalloproteins and high-valent metal-complexes at room temperature using free-electron lasers
JF  - Structural dynamics
N2  - X-ray absorption spectroscopy at the L-edge of 3d transition metals provides unique information on the local metal charge and spin states by directly probing 3d-derived molecular orbitals through 2p-3d transitions. However, this soft x-ray technique has been rarely used at synchrotron facilities for mechanistic studies of metalloenzymes due to the difficulties of x-ray-induced sample damage and strong background signals from light elements that can dominate the low metal signal. Here, we combine femtosecond soft x-ray pulses from a free-electron laser with a novel x-ray fluorescence-yield spectrometer to overcome these difficulties. We present L-edge absorption spectra of inorganic high-valent Mn complexes (Mn similar to 6-15 mmol/l) with no visible effects of radiation damage. We also present the first L-edge absorption spectra of the oxygen evolving complex (Mn4CaO5) in Photosystem II (Mn < 1 mmol/l) at room temperature, measured under similar conditions. Our approach opens new ways to study metalloenzymes under functional conditions. (C) 2017 Author(s).
Y1  - 2017
U6  - https://doi.org/10.1063/1.4986627
SN  - 2329-7778
VL  - 4
PB  - American Institute of Physics
CY  - Melville
ER  - 
TY  - JOUR
A1  - Eggert, Kai
A1  - Rawel, Harshadrai Manilal
A1  - Nikfardjam, Martin S. Pour
A1  - Kroll, Jürgen
T1  - Interactions between lysozyme and wine components
JF  - Deutsche Lebensmittel-Rundschau : DLR
N2  - The addition of lysozyme amounting to 1000 mg/l wine does neither effect its total phenol content (Folin-Ciocalteu-Method), nor wine colour (measured by extinction at 512 nm) nor its antioxidative capacity (TEAC-Assay). No covalent binding of wine phenols to the enzyme was observed during lysozyme addition, although non-covalent interactions are possible. Lysozyme activity is not influenced by the presence of malvidin-3-glucoside and resveratrol in model experiments, whereas pH and ethanol content produce a corresponding alteration in lysozyme activity. With regard to red wine, a significant effect was noted in the presence of wine components.
KW  - lysozyme
KW  - red wine
KW  - total phenol content
KW  - colour
KW  - antioxidative capacity
KW  - lysozyme activity
Y1  - 2006
SN  - 0012-0413
VL  - 102
IS  - 10
SP  - 472
EP  - 478
PB  - Behr
CY  - Stuttgart
ER  - 
TY  - JOUR
A1  - Petzke, Klaus-Jürgen
A1  - Schuppe, S.
A1  - Rohn, Sascha
A1  - Rawel, Harshadrai Manilal
A1  - Kroll, Jürgen
T1  - Chlorogenic acid moderately decreases the quality of whey proteins in rats
N2  - During processing and storage, phenolic compounds (PCs) may react with food protein bound amino acids (AAs). Such reactions have been reported to change physicochemical and to decrease in vitro digestion properties of proteins. A rat growth and nitrogen (N) balance study was conducted to prove whether derivatization with chlorogenic acid (CA) affects the nutritional quality of beta-lactoglobulin (beta-LG). Test diets (10% protein level) contained nonderivatized beta-LG (LG, treated under omission of CA), low derivatization level beta-LG (LGL), high derivatization level beta-LG (LGH), or casein supplemented with L-methionine (0.3% of diet; C+met) as an internal standard. An additional group received untreated beta-LG supplemented with pure CA (1.03% of diet; LG+CA). The AA composition of test proteins, plasma AAs, and liver glutathione (GSH) concentrations were determined. Protein digestibility-corrected amino acid score (PDCAAS) was calculated using human or rat AA requirement patterns and rat fecal digestibility values. N excretion was significantly higher in feces and lower in urine of rats fed with LGH as compared to LG and LGL. Consequently, true N digestibility (TND) was significantly lower with LGH as compared to LG and LGL. The lower content of methionine, cysteine, lysine, and tryptophan in LGH corresponded to a reduced TND. Net protein utilization (NPU) was not different between treated beta-LG fed diet groups but was lower than in LG+CA and C+met fed groups. Only at a relatively high level of derivatization with CA, the otherwise good nutritional quality of beta-LG is affected so that TND is reduced, while NPU still remains unaffected. Derivatization of beta-LG with CA does not seem to lead to an additional deficiency in a specific indispensable AA in growing rats fed with 10% protein
Y1  - 2005
SN  - 0021-8561
ER  - 
TY  - JOUR
A1  - Zoller, Peter
A1  - Beth, Thomas
A1  - Binosi, D.
A1  - Blatt, Rainer
A1  - Briegel, Hans J.
A1  - Bruss, D.
A1  - Calarco, Tommaso
A1  - Cirac, Juan Ignacio
A1  - Deutsch, David
A1  - Eisert, Jens
A1  - Ekert, Artur
A1  - Fabre, Claude
A1  - Gisin, Nicolas
A1  - Grangiere, P.
A1  - Grassl, Markus
A1  - Haroche, Serge
A1  - Imamoglu, Atac
A1  - Karlson, A.
A1  - Kempe, Julia
A1  - Kouwenhoven, Leo P.
A1  - Kröll, S.
A1  - Leuchs, Gerd
A1  - Lewenstein, Maciej
A1  - Loss, Daniel
A1  - Lütkenhaus, Norbert
A1  - Massar, Serge
A1  - Mooij, J. E.
A1  - Plenio, Martin Bodo
A1  - Polzik, Eugene
A1  - Popescu, Sandu
A1  - Rempe, Gerhard
A1  - Sergienko, Alexander
A1  - Suter, David
A1  - Twamley, John
A1  - Wendin, Göran
A1  - Werner, Reinhard F.
A1  - Winter, Andreas
A1  - Wrachtrup, Jörg
A1  - Zeilinger, Anton
T1  - Quantum information processing and communication : Strategic report on current status, visions and goals for research in Europe
N2  - We present an excerpt of the document "Quantum Information Processing and Communication: Strategic report on current status, visions and goals for research in Europe", which has been recently published in electronic form at the website of FET (the Future and Emerging Technologies Unit of the Directorate General Information Society of the European Commission, http://www.cordis.lu/ist/fet/qipc-sr.htm). This document has been elaborated, following a former suggestion by FET, by a committee of QIPC scientists to provide input towards the European Commission for the preparation of the Seventh Framework Program. Besides being a document addressed to policy makers and funding agencies (both at the European and national level), the document contains a detailed scientific assessment of the state-of-the-art, main research goals, challenges, strengths, weaknesses, visions and perspectives of all the most relevant QIPC sub-fields, that we report here
Y1  - 2005
SN  - 1434-6060
ER  - 
TY  - JOUR
A1  - Kroll, Thomas
A1  - Kern, Jan
A1  - Kubin, Markus
A1  - Ratner, Daniel
A1  - Gul, Sheraz
A1  - Fuller, Franklin D.
A1  - Löchel, Heike
A1  - Krzywinski, Jacek
A1  - Lutman, Alberto
A1  - Ding, Yuantao
A1  - Dakovski, Georgi L.
A1  - Moeller, Stefan
A1  - Turner, Joshua J.
A1  - Alonso-Mori, Roberto
A1  - Nordlund, Dennis L.
A1  - Rehanek, Jens
A1  - Weniger, Christian
A1  - Firsov, Alexander
A1  - Brzhezinskaya, Maria
A1  - Chatterjee, Ruchira
A1  - Lassalle-Kaiser, Benedikt
A1  - Sierra, Raymond G.
A1  - Laksmono, Hartawan
A1  - Hill, Ethan
A1  - Borovik, Andrew S.
A1  - Erko, Alexei
A1  - Föhlisch, Alexander
A1  - Mitzner, Rolf
A1  - Yachandra, Vittal K.
A1  - Yano, Junko
A1  - Wernet, Philippe
A1  - Bergmann, Uwe
T1  - X-ray absorption spectroscopy using a self-seeded soft X-ray free-electron laser
JF  - Optics express : the international electronic journal of optics
N2  - X-ray free electron lasers (XFELs) enable unprecedented new ways to study the electronic structure and dynamics of transition metal systems. L-edge absorption spectroscopy is a powerful technique for such studies and the feasibility of this method at XFELs for solutions and solids has been demonstrated. However, the required x-ray bandwidth is an order of magnitude narrower than that of self-amplified spontaneous emission (SASE), and additional monochromatization is needed. Here we compare L-edge x-ray absorption spectroscopy (XAS) of a prototypical transition metal system based on monochromatizing the SASE radiation of the linac coherent light source (LCLS) with a new technique based on self-seeding of LCLS. We demonstrate how L-edge XAS can be performed using the self-seeding scheme without the need of an additional beam line monochromator. We show how the spectral shape and pulse energy depend on the undulator setup and how this affects the x-ray spectroscopy measurements. (C) 2016 Optical Society of America
Y1  - 2016
U6  - https://doi.org/10.1364/OE.24.022469
SN  - 1094-4087
VL  - 24
SP  - 22469
EP  - 22480
PB  - Optical Society of America
CY  - Washington
ER  -