TY  - JOUR
A1  - Martinez, Ronny
A1  - Jakob, Felix
A1  - Tu, Ran
A1  - Siegert, Petra
A1  - Maurer, Karl-Heinz
A1  - Schwaneberg, Ulrich
T1  - Increasing activity and thermal resistance of Bacillus gibsonii alkaline protease (BgAP) by directed evolution
JF  - Biotechnology and bioengineering
Y1  - 2013
SN  - 1097-0290 (E-Journal); 0006-3592 (Print); 0368-1467 (Print)
VL  - Vol. 110
IS  - Iss. 3
SP  - 711
EP  - 720
PB  - Wiley
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Jakob, Felix
A1  - Martinez, Ronny
A1  - Mandawe, John
A1  - Hellmuth, Hendrik
A1  - Siegert, Petra
A1  - Maurer, Karl-Heinz
A1  - Schwaneberg, Ulrich
T1  - Surface charge engineering of a Bacillus gibsonii subtilisin protease
JF  - Applied microbiology and biotechnology
Y1  - 2013
SN  - 1432-0614 (E-Journal); 0171-1741 (Print); 0175-7598 (Print); 0340-2118 (Print)
VL  - Vol. 97
IS  - Iss. 15
SP  - 6793
EP  - 6802
PB  - Springer
CY  - Berlin
ER  - 
TY  - JOUR
A1  - Scheer, Nico
A1  - Snaith, Mike
A1  - Wolf, C. Roland
A1  - Seibler, Jost
T1  - Generation and utility of genetically humanized mouse models
JF  - Drug Discovery Today
Y1  - 2013
U6  - http://dx.doi.org/10.1016/j.drudis.2013.07.007
SN  - 1359-6446
VL  - Vol 18
IS  - 23-24
SP  - 1200
EP  - 1211
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Bouwman, Peter
A1  - Gulden, Hanneke van der
A1  - Heijden, Ingrid van der
A1  - Drost, Rinske
A1  - Klijn, Christiaan N.
A1  - Prasetyanti, Pramudita
A1  - Pieterse, Mark
A1  - Wientjens, Ellen
A1  - Seibler, Jost
A1  - Hogervorst, Frank B. L.
A1  - Jonkers, Jos
T1  - A High-Throughput Functional Complementation Assay for Classification of BRCA1 Missense Variants
JF  - Cancer Discovery
Y1  - 2013
U6  - http://dx.doi.org/10.1158/2159-8290.CD-13-0094
SN  - 2159-8290
IS  - 3
SP  - 1142
EP  - 1152
ER  - 
TY  - JOUR
A1  - Michalak, Ewa Malgorzata
A1  - Nacerddine, Karim
A1  - Pietersen, Alexandra
A1  - Beuger, Vincent
A1  - Pawlitzky, Inka
A1  - Cornelissen-Steijger, Paulien
A1  - Wientjens, Ellen
A1  - Tanger, Ellen
A1  - Seibler, Jost
A1  - Lohuizen, Maarten van
A1  - Jonkers, Jos
T1  - Polycomb group gene Ezh2 regulates mammary gland morphogenesis and maintains the luminal progenitor pool
JF  - Stem Cells
Y1  - 2013
U6  - http://dx.doi.org/10.1002/stem.1437
SN  - 1549-4918
VL  - Vol 31
IS  - 9
SP  - 1910
EP  - 1920
PB  - Oxford University Press
CY  - Oxford
ER  - 
TY  - JOUR
A1  - Gebeshuber, Christoph A.
A1  - Kornauth, Christoph
A1  - Dong, Lihua
A1  - Sierig, Ralph
A1  - Seibler, Jost
A1  - Reiss, Martina
A1  - Tauber, Stefanie
A1  - Bilban, Martin
A1  - Wang, Shijun
A1  - Kain, Renate
A1  - Böhmig, Georg A.
A1  - Moeller, Marcus J.
A1  - Gröne, Hermann-Josef
A1  - Englert, Christoph
A1  - Martinez, Javier
A1  - Kerjaschki, Dontscho
T1  - Focal segmental glomerulosclerosis is induced by microRNA-193a and its downregulation of WT1
JF  - Nature Medicine
Y1  - 2013
U6  - http://dx.doi.org/10.1038/nm.3142
SN  - 1078-8956
VL  - 19
IS  - 4
SP  - 481
EP  - 487
ER  - 
TY  - JOUR
A1  - Kornfeld, Jan-Wilhelm
A1  - Baitzel, Catherina
A1  - Könner, A. Christine
A1  - Nicholls, Hayley T.
A1  - Vogt, Merly C.
A1  - Herrmanns, Karolin
A1  - Scheja, Ludger
A1  - Haumaitre, Cécile
A1  - Wolf, Anna M.
A1  - Knippschild, Uwe
A1  - Seibler, Jost
A1  - Cereghini, Silvia
A1  - Heeren, Joerg
A1  - Stoffel, Markus
A1  - Brüning, Jens C.
T1  - Obesity-induced overexpression of miR-802 impairs glucose metabolism through silencing of Hnf1b
JF  - Nature
Y1  - 2013
SN  - 0028-0836
U6  - http://dx.doi.org/10.1038/nature11793
VL  - 494
IS  - 7435
SP  - 111
EP  - 115
PB  - Springer Nature
CY  - Cham
ER  - 
TY  - JOUR
A1  - Wiegand, Sandra
A1  - Voigt, Birgit
A1  - Albrecht, Dirk
A1  - Bongaerts, Johannes
A1  - Evers, Stefan
A1  - Hecker, Michael
A1  - Daniel, Rolf
A1  - Liesegang, Heiko
T1  - Fermentation stage-dependent adaptations of Bacillus licheniformis during enzyme production
JF  - Microbial Cell Factories
Y1  - 2013
U6  - http://dx.doi.org/10.1186/1475-2859-12-120
SN  - 1475-2859
VL  - 12
SP  - 120
PB  - Biomed Central
CY  - London
ER  - 
TY  - JOUR
A1  - Thiel, Alexander
A1  - Tippkötter, Nils
A1  - Suck, Kirstin
A1  - Sohling, Ulrich
A1  - Ruf, Friedrich
A1  - Ulber, Roland
T1  - New zeolite adsorbents for downstream processing of polyphenols from renewable resources
JF  - Engineering in Life Sciences
N2  - Commercial materials with polyvinylpolypyrrolidone and polymeric amberlites (XAD7HP, XAD16) are commonly used for the adsorptive downstream processing of polyphenols from renewable resources. In this study, beta-zeolite-based adsorbent systems were examined, and their properties were compared to organic resins. Batch adsorption experiments were conducted with synthetic solutions of major polyphenols. Adsorption isotherms and desorption characteristics of individual adsorbent were determined based on these results. Maximum adsorption capacities were calculated using the Langmuir model. For example, the zeolites had capacities up to 203.2 mg/g for ferulic acid. To extend these results to a complex system, additional experiments were performed on rapeseed meal and wheat seed extracts as representative renewable resources. HPLC analysis showed that with 7.5% w/v, which is regarded as the optimum amount of zeolites, zeolites A and B could bind 100% of the major polyphenols as well as release polyphenols at high yields. Additionally, regeneration experiments were performed with isopropyl alcohol at 99°C to evaluate how zeolites regenerate under mild conditions. The results showed only a negligible loss of adsorption capacity and no loss of desorption capacity. In summary, it was concluded that beta-zeolites were promising adsorbents for developing new processes to isolate polyphenols from renewable resources.
Y1  - 2013
U6  - http://dx.doi.org/10.1002/elsc.201200188
VL  - 13
IS  - 3
SP  - 239
EP  - 246
PB  - Wiley
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Tippkötter, Nils
A1  - Al-Kaidy, Huschyar
A1  - Wollny, Steffen
A1  - Ulber, Roland
T1  - Functionalized magnetizable particles for downstream processing in single-use systems
JF  - Chemie Ingenieur Technik
N2  - Biotechnological downstream processing is usually an elaborate procedure, requiring a multitude of unit operations to isolate the target component. Besides the disadvantageous space-time yield, the risks of cross-contaminations and product loss grow fast with the complexity of the isolation procedure. A significant reduction of unit operations can be achieved by application of magnetic particles, especially if these are functionalized with affinity ligands. As magnetic susceptible materials are highly uncommon in biotechnological processes, target binding and selective separation of such particles from fermentation or reactions broths can be done in a single step. Since the magnetizable particles can be produced from iron salts and low priced polymers, a single-use implementation of these systems is highly conceivable. In this article, the principles of magnetizable particles, their synthesis and functionalization are explained. Furthermore, applications in the area of reaction engineering, microfluidics and downstream processing are discussed focusing on established single-use technologies and development potential.
Y1  - 2013
U6  - http://dx.doi.org/10.1002/cite.201200130
VL  - 85
IS  - 1-2: Special Issue: Single-Use Technology
SP  - 76
EP  - 86
PB  - Wiley
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Pellegrini, Paul A.
A1  - Howell, Nicholas R.
A1  - Shepherd, Rachael K.
A1  - Lengkeek, Nigel A.
A1  - Paulßen, Elisabeth
A1  - Katsifis, Andrew G.
A1  - Greguric, Ivan
T1  - Synthesis and Radiolabelling of DOTA-Linked Glutamine Analogues with 67,68Ga as Markers for Increased Glutamine Metabolism in Tumour Cells
JF  - Molecules
Y1  - 2013
U6  - http://dx.doi.org/10.3390/molecules18067160
SN  - 1420-3049
VL  - 18
IS  - 6
SP  - 7160
EP  - 7178
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Paulßen, Elisabeth
A1  - Le, Van So
A1  - Lengkeek, Nigel
A1  - Pellegrini, Paul
A1  - Jackson, Tim
A1  - Greguric, Ivan
A1  - Weiner, Ron
T1  - Influence of Metal Ions on the 68Ga-labeling of DOTATATE
JF  - Applied Radiation and Isotopes
Y1  - 2013
U6  - http://dx.doi.org/10.1016/j.apradiso.2013.08.010
SN  - 1872-9800
VL  - 82
SP  - 232
EP  - 238
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Scheer, Nico
A1  - Wolf, C. Roland
T1  - Xenobiotic receptor humanized mice and their utility
JF  - Drug Metabolism Reviews
Y1  - 2013
U6  - http://dx.doi.org/10.3109/03602532.2012.738687
SN  - 1097-9883
IS  - 1
SP  - 110
EP  - 121
PB  - Taylor & Francis
CY  - London
ER  - 
TY  - JOUR
A1  - Huck, Christina
A1  - Schiffels, Johannes
A1  - Herrera, Cony N.
A1  - Schelden, Maximilian
A1  - Selmer, Thorsten
A1  - Poghossian, Arshak
A1  - Baumann, Marcus
A1  - Wagner, Patrick
A1  - Schöning, Michael Josef
T1  - Metabolic responses of Escherichia coli upon glucose pulses captured by a capacitive field-effect sensor
JF  - Physica Status Solidi (A)
N2  - Living cells are complex biological systems transforming metabolites taken up from the surrounding medium. Monitoring the responses of such cells to certain substrate concentrations is a challenging task and offers possibilities to gain insight into the vitality of a community influenced by the growth environment. Cell-based sensors represent a promising platform for monitoring the metabolic activity and thus, the “welfare” of relevant organisms. In the present study, metabolic responses of the model bacterium Escherichia coli in suspension, layered onto a capacitive field-effect structure, were examined to pulses of glucose in the concentration range between 0.05 and 2 mM. It was found that acidification of the surrounding medium takes place immediately after glucose addition and follows Michaelis–Menten kinetic behavior as a function of the glucose concentration. In future, the presented setup can, therefore, be used to study substrate specificities on the enzymatic level and may as well be used to perform investigations of more complex metabolic responses. Conclusions and perspectives highlighting this system are discussed.
Y1  - 2013
U6  - http://dx.doi.org/10.1002/pssa.201200900
SN  - 0031-8965
VL  - 210
IS  - 5
SP  - 926
EP  - 931
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Bäcker, Matthias
A1  - Rakowski, D.
A1  - Poghossian, Arshak
A1  - Biselli, Manfred
A1  - Wagner, Patrick
A1  - Schöning, Michael Josef
T1  - Chip-based amperometric enzyme sensor system for monitoring of bioprocesses by flow-injection analysis
JF  - Journal of Biotechnology
N2  - A microfluidic chip integrating amperometric enzyme sensors for the detection of glucose, glutamate and glutamine in cell-culture fermentation processes has been developed. The enzymes glucose oxidase, glutamate oxidase and glutaminase were immobilized by means of cross-linking with glutaraldehyde on platinum thin-film electrodes integrated within a microfluidic channel. The biosensor chip was coupled to a flow-injection analysis system for electrochemical characterization of the sensors. The sensors have been characterized in terms of sensitivity, linear working range and detection limit. The sensitivity evaluated from the respective peak areas was 1.47, 3.68 and 0.28 μAs/mM for the glucose, glutamate and glutamine sensor, respectively. The calibration curves were linear up to a concentration of 20 mM glucose and glutamine and up to 10 mM for glutamate. The lower detection limit amounted to be 0.05 mM for the glucose and glutamate sensor, respectively, and 0.1 mM for the glutamine sensor. Experiments in cell-culture medium have demonstrated a good correlation between the glutamate, glutamine and glucose concentrations measured with the chip-based biosensors in a differential-mode and the commercially available instrumentation. The obtained results demonstrate the feasibility of the realized microfluidic biosensor chip for monitoring of bioprocesses.
Y1  - 2013
U6  - http://dx.doi.org/10.1016/j.jbiotec.2012.03.014
SN  - 0168-1656
VL  - 163
IS  - 4
SP  - 371
EP  - 376
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Winckler, Silvia
A1  - Krueger, Rolf
A1  - Schnitzler, Thomas
A1  - Zang, Werner
A1  - Fischer, Rainer
A1  - Biselli, Manfred
T1  - A sensitive monitoring system for mammalian cell cultivation processes: a PAT approach
JF  - Bioprocess and biosystems engineering
N2  - Biopharmaceuticals such as antibodies are produced in cultivated mammalian cells, which must be monitored to comply with good manufacturing practice. We, therefore, developed a fully automated system comprising a specific exhaust gas analyzer, inline analytics and a corresponding algorithm to precisely determine the oxygen uptake rate, carbon dioxide evolution rate, carbon dioxide transfer rate, transfer quotient and respiratory quotient without interrupting the ongoing cultivation, in order to assess its reproducibility. The system was verified using chemical simulation experiments and was able to measure the respiratory activity of hybridoma cells and DG44 cells (derived from Chinese hamster ovary cells) with satisfactory results at a minimum viable cell density of ~2.0 × 10⁵ cells ml⁻¹. The system was suitable for both batch and fed-batch cultivations in bubble-aerated and membrane-aerated reactors, with and without the control of pH and dissolved oxygen.
Y1  - 2014
U6  - http://dx.doi.org/10.1007/s00449-013-1062-8
SN  - 1615-7591 (Print) 1615-7605 (Online)
VL  - 37
IS  - 5
SP  - 901
EP  - 912
PB  - Springer
CY  - Berlin, Heidelberg
ER  - 
TY  - JOUR
A1  - Heinze, Daniel
A1  - Mang, Thomas
A1  - Peter, Karin
A1  - Möller, Martin
A1  - Weichold, Oliver
T1  - Synthesis of low molecular weight poly(vinyl acetate) and its application as plasticizer
JF  - Journal of applied polymer science
N2  - Poly(vinyl acetate), PVAc, with a degree of polymerization Xn = 10 was prepared by chain-transfer radical polymerization using carbon tetrachloride and used as oligomeric plasticizer for commercial PVAc. However, the chlorinated chain ends cause a low thermal stability requiring mild Cl/H substitution. The product exhibits high thermal stability and excellent melt-compounding properties. Blends of oligomeric and commercial PVAc show single glass transition temperatures which decrease with higher oligomer content and exhibit small negative deviations from Fox' linear additivity rule. This indicates plasticization and miscibility being mainly due to entropic effects. Injection-moulded thick specimens show ductile behaviour at oligomer contents >10 wt %, while sheets with a thickness of 0.2–0.5 mm appear flexible already at 7.5 wt %. The oxygen permeability coefficients are an order of magnitude lower than those of low-density polyethylene. Due to the sum of their properties, the plasticized sheets present a promising alternative in the preparation of barrier materials.
Y1  - 2014
U6  - http://dx.doi.org/10.1002/app.40226
SN  - 1097-4628 (E-Journal); 0021-8995 (Print)
VL  - 131
IS  - 9
SP  - Article No. 40226
PB  - Wiley
CY  - New York
ER  - 
TY  - JOUR
A1  - Wang, Ren-Qi
A1  - Druckenmüller, Katharina
A1  - Elbers, Gereon
A1  - Guenther, Klaus
A1  - Croué, Jean-Philippe
T1  - Analysis of aquatic-phase natural organic matter by optimized LDI-MS method
JF  - Journal of mass spectrometry
N2  - The composition and physiochemical properties of aquatic-phase natural organic matter (NOM) are most important problems for both environmental studies and water industry. Laser desorption/ionization (LDI) mass spectrometry facilitated successful examinations of NOM, as humic and fulvic acids in NOM are readily ionized by the nitrogen laser. In this study, hydrophobic NOMs (HPO NOMs) from river, reservoir and waste water were characterized by this technique. The effect of analytical variables like concentration, solvent composition and laser energy was investigated. The exact masses of small molecular NOM moieties in the range of 200–1200 m/z were determined in reflectron mode. In addition, spectra of post-source-decay experiments in this range showed that some compounds from different natural NOMs had the same fragmental ions. In the large mass range of 1200–15 000 Da, macromolecules and their aggregates were found in HPO NOMs from natural waters. Highly humic HPO exhibited mass peaks larger than 8000 Da. On the other hand, the waste water and reservoir water mainly had relatively smaller molecules of about 2000 Da. The LDI-MS measurements indicated that highly humic river waters were able to form large aggregates and membrane foulants, while the HPO NOMs from waste water and reservoir water were unlikely to form large aggregates. Copyright © 2014 John Wiley & Sons, Ltd.
Y1  - 2014
U6  - http://dx.doi.org/10.1002/jms.3321
SN  - 1096-9888
VL  - 49
IS  - 2
SP  - 154
EP  - 160
PB  - Wiley
CY  - Bognor Regis
ER  - 
TY  - JOUR
A1  - Heine, A.
A1  - Herrmann, G.
A1  - Selmer, Thorsten
A1  - Terwesten, F.
A1  - Buckel, W.
A1  - Reuter, K.
T1  - High resolution crystal structure of clostridium propionicum β-Alanyl-CoA:Ammonia Lyase, a new member of the "Hot Dog Fold" protein superfamily
JF  - Proteins
N2  - Clostridium propionicum is the only organism known to ferment β-alanine, a constituent of coenzyme A (CoA) and the phosphopantetheinyl prosthetic group of holo-acyl carrier protein. The first step in the fermentation is a CoA-transfer to β-alanine. Subsequently, the resulting β-alanyl-CoA is deaminated by the enzyme β-alanyl-CoA:ammonia lyase (Acl) to reversibly form ammonia and acrylyl-CoA. We have determined the crystal structure of Acl in its apo-form at a resolution of 0.97 Å as well as in complex with CoA at a resolution of 1.59 Å. The structures reveal that the enyzme belongs to a superfamily of proteins exhibiting a so called “hot dog fold” which is characterized by a five-stranded antiparallel β-sheet with a long α-helix packed against it. The functional unit of all “hot dog fold” proteins is a homodimer containing two equivalent substrate binding sites which are established by the dimer interface. In the case of Acl, three functional dimers combine to a homohexamer strongly resembling the homohexamer formed by YciA-like acyl-CoA thioesterases. Here, we propose an enzymatic mechanism based on the crystal structure of the Acl·CoA complex and molecular docking. Proteins 2014; 82:2041–2053. © 2014 Wiley Periodicals, Inc.
Y1  - 2014
U6  - http://dx.doi.org/10.1002/prot.24557
SN  - 1097-0134 (E-Journal); 0887-3585 (Print)
VL  - 82
IS  - 9
SP  - 2041
EP  - 2053
PB  - Wiley-Liss
CY  - New York
ER  - 
TY  - JOUR
A1  - Takenaga, Shoko
A1  - Biselli, Manfred
A1  - Schnitzler, Thomas
A1  - Öhlschläger, Peter
A1  - Wagner, Torsten
A1  - Schöning, Michael Josef
T1  - Toward multi-analyte bioarray sensors: LAPS-based on-chip determination of a Michaelis–Menten-like kinetics for cell culturing
JF  - Physica status solidi A : Applications and materials science
N2  - The metabolic activity of Chinese hamster ovary (CHO) cells was observed using a light-addressable potentiometric sensor (LAPS). The dependency toward different glucose concentrations (17–200 mM) follows a Michaelis–Menten kinetics trajectory with Kₘ = 32.8 mM, and the obtained Kₘ value in this experiment was compared with that found in literature. In addition, the pH shift induced by glucose metabolism of tumor cells transfected with the HPV-16 genome (C3 cells) was successfully observed. These results indicate the possibility to determine the tumor cells metabolism with a LAPS-based measurement device.
Y1  - 2014
U6  - http://dx.doi.org/10.1002/pssa.201330464
SN  - 1521-396X (E); 1862-6319 (E-Journal); 0031-8965 (Print); 1862-6300 (Print)
VL  - 211
IS  - 6
SP  - 1410
EP  - 1415
PB  - Wiley-VCH
CY  - Weinheim
ER  -