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 - Selmer, Thorsten A1 - Pinkenburg, Olaf T1 - Method of cloning at least one nucleic acid molecule of interest using type IIS restriction endonucleases, and corresponding cloning vectors, kits and system using type IIS restriction endonucleases / Selmer, Thorsten ; Pinkenburg, Olaf Y1 - 2008 N1 - Patent No. WO 2008095927 A1 Aug 14, 2008 ER - TY - BOOK A1 - Selmer, Thorsten T1 - Nachweis einer neuartigen posttranslationalen Modifikation in Sulfatasen und ihr Fehlen in Enzymen aus Patienten mit multipler Sulfatase-Defizienz Y1 - 1996 N1 - Zugl.: Göttingen, Univ., Diss., 1996 PB - Cuvillier CY - Göttingen ER - TY - JOUR A1 - Selmer, Thorsten A1 - Pierik, Antonio J. A1 - Heider, Johann T1 - New glycyl radical enzymes catalysing key metabolic steps in anaerobic bacteria JF - Biological Chemistry. 386 (2005), H. 10 Y1 - 2005 SN - 1431-6730 SP - 981 EP - 988 ER - TY - JOUR A1 - Selmer, Thorsten A1 - Jennemann, Richard A1 - Bauer, Bernhard L. A1 - Bertalanffy, Helmut T1 - Novel glycoinositolphosphosphingolipids, basidiolipids, from Agaricus / Jennemann, Richard ; Bauer, Bernhard, L. ; Bertalanffy, Helmut ; Geyer, Rudolf ; Gschwind, Ruth, M. ; Selmer, Thorsten ; Wiegandt, Herbert JF - European Journal of Biochemistry. 259 (1999), H. 1-2 Y1 - 1999 SN - 0014-2956 SP - 331 EP - 338 ER - TY - JOUR A1 - Werner, Frederik A1 - Groebel, Simone A1 - Krumbe, Christoph A1 - Wagner, Torsten A1 - Selmer, Thorsten A1 - Yoshinobu, Tatsuo A1 - Baumann, Marcus A1 - Schöning, Michael Josef T1 - Nutrient concentration-sensitive microorganism-based biosensor JF - Physica Status Solidi (a) Y1 - 2012 U6 - http://dx.doi.org/10.1002/pssa.201100801 SN - 1862-6319 VL - 209 IS - 5 SP - 900 EP - 904 PB - Wiley-VCH CY - Weinheim ER - TY - JOUR A1 - Pilas, Johanna A1 - Yazici, Yasemen A1 - Selmer, Thorsten A1 - Keusgen, Michael A1 - Schöning, Michael Josef T1 - Optimization of an amperometric biosensor array for simultaneous measurement of ethanol, formate, d- and l-lactate JF - Electrochimica Acta N2 - The immobilization of NAD+-dependent dehydrogenases, in combination with a diaphorase, enables the facile development of multiparametric sensing devices. In this work, an amperometric biosensor array for simultaneous determination of ethanol, formate, d- and l-lactate is presented. Enzyme immobilization on platinum thin-film electrodes was realized by chemical cross-linking with glutaraldehyde. The optimization of the sensor performance was investigated with regard to enzyme loading, glutaraldehyde concentration, pH, cofactor concentration and temperature. Under optimal working conditions (potassium phosphate buffer with pH 7.5, 2.5 mmol L-1 NAD+, 2.0 mmol L-1 ferricyanide, 25 °C and 0.4% glutaraldehyde) the linear working range and sensitivity of the four sensor elements was improved. Simultaneous and cross-talk free measurements of four different metabolic parameters were performed successfully. The reliable analytical performance of the biosensor array was demonstrated by application in a clarified sample of inoculum sludge. Thereby, a promising approach for on-site monitoring of fermentation processes is provided. KW - Simultaneous determination KW - Enzymatic biosensor KW - Diaphorase KW - Dehydrogenase Y1 - 2017 U6 - http://dx.doi.org/10.1016/j.electacta.2017.07.119 SN - 0013-4686 VL - 251 SP - 256 EP - 262 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Pilas, Johanna A1 - Mariano, K. A1 - Keusgen, M. A1 - Selmer, Thorsten A1 - Schöning, Michael Josef T1 - Optimization of an Enzyme-based Multi-parameter Biosensor for Monitoring Biogas Processes JF - Procedia Engineering Y1 - 2015 U6 - http://dx.doi.org/10.1016/j.proeng.2015.08.702 SN - 1877-7058 N1 - Part of special issue "Eurosensors 2015" VL - 120 SP - 532 EP - 535 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Selmer, Thorsten A1 - Buckel, Wolfgang T1 - Oxygen Exchange between Acetate and the Catalytic Glutamate Residue in Glutaconate CoA-transferase from Acidaminococcus fermentans. IMPLICATIONS FOR THE MECHANISM OF CoA-ESTER HYDROLYSIS JF - Journal of Biological Chemistry. 274 (1999), H. 30 Y1 - 1999 SN - 1083-351X SP - 20772 EP - 20778 ER - TY - JOUR A1 - Selmer, Thorsten A1 - Andrei, Paula I. T1 - p-Hydroxyphenylacetate decarboxylase from Clostridium difficile. A novel glycyl radical enzyme catalysing the formation of p-cresol JF - European Journal of Biochemistry. 268 (2001), H. 5 Y1 - 2001 SN - 0014-2956 SP - 1363 EP - 1372 ER -