TY  - JOUR
A1  - Haeger, Gerrit
A1  - Probst, Johanna
A1  - Jaeger, Karl-Erich
A1  - Bongaerts, Johannes
A1  - Siegert, Petra
T1  - Novel aminoacylases from Streptomyces griseus DSM 40236 and their recombinant production in Streptomyces lividans
JF  - FEBS Open Bio
N2  - Amino acid-based surfactants are valuable compounds for cosmetic formulations. The chemical synthesis of acyl-amino acids is conventionally performed by the Schotten-Baumann reaction using fatty acyl chlorides, but aminoacylases have also been investigated for use in biocatalytic synthesis with free fatty acids. Aminoacylases and their properties are diverse; they belong to different peptidase families and show differences in substrate specificity and biocatalytic potential. Bacterial aminoacylases capable of synthesis have been isolated from Burkholderia, Mycolicibacterium, and Streptomyces. Although several proteases and peptidases from S. griseus have been described, no aminoacylases from this species have been identified yet. In this study, we investigated two novel enzymes produced by S. griseus DSM 40236ᵀ . We identified and cloned the respective genes and recombinantly expressed an α-aminoacylase (EC 3.5.1.14), designated SgAA, and an ε-lysine acylase (EC 3.5.1.17), designated SgELA, in S. lividans TK23. The purified aminoacylase SgAA was biochemically characterized, focusing on its hydrolytic activity to determine temperature- and pH optima and stabilities. The aminoacylase could hydrolyze various acetyl-amino acids at the Nα -position with a broad specificity regarding the sidechain. Substrates with longer acyl chains, like lauroyl-amino acids, were hydrolyzed to a lesser extent. Purified aminoacylase SgELA specific for the hydrolysis of Nε -acetyl-L-lysine was unstable and lost its enzymatic activity upon storage for a longer period but could initially be characterized. The pH optimum of SgELA was pH 8.0. While synthesis of acyl-amino acids was not observed with SgELA, SgAA catalyzed the synthesis of lauroyl-methionine.
KW  - Streptomyces lividans
KW  - recombinant expression
KW  - Streptomyces griseus
KW  - ε-lysine acylase
KW  - α-aminoacylase
Y1  - 2023
U6  - http://dx.doi.org/10.1002/2211-5463.13723
SN  - 2211-5463
N1  - Corresponding author: Petra Siegert
VL  - 13
IS  - 12
SP  - 2224
EP  - 2238
PB  - Wiley
CY  - Hoboken, NJ
ER  - 
TY  - JOUR
A1  - Wagner, Torsten
A1  - Miyamoto, Ko-ichiro
A1  - Schöning, Michael Josef
A1  - Yoshinobu, Tatsuo
T1  - Novel combination of digital light processing (DLP) and light-addressable potentiometric sensors (LAPS) for flexible chemical imaging
JF  - Procedia Engineering. 5 (2010)
Y1  - 2010
SN  - 1877-7058
N1  - Eurosensor XXIV Conference
SP  - 520
EP  - 523
ER  - 
TY  - JOUR
A1  - Poghossian, Arshak
A1  - Berndsen, Lars
A1  - Lüth, Hans
A1  - Schöning, Michael Josef
T1  - Novel concepts for flow-rate and flow-direction determination by means of pH-sensitive ISFETs
JF  - Proceedings of SPIE. 4560 (2001)
Y1  - 2001
SP  - 19
EP  - 27
ER  - 
TY  - JOUR
A1  - Schöning, Michael Josef
A1  - Lüth, H.
T1  - Novel concepts for silicon-based biosensors
JF  - Physica Status Solidi (A) (2001)
Y1  - 2001
SN  - 0031-8965
SP  - 65
EP  - 77
ER  - 
TY  - JOUR
A1  - Schöning, Michael Josef
A1  - Malkoc, Ü.
A1  - Thust, M.
A1  - Steffen, A.
A1  - Kordos, P.
A1  - Lüth, H.
T1  - Novel electrochemical sensors with structured and porous semiconductor/insulator capacitors
JF  - Sensors and Actuators B. 65 (2000), H. 1-3
Y1  - 2000
SN  - 0925-4005
SP  - 288
EP  - 290
ER  - 
TY  - CHAP
A1  - Arida, Hassan A.
A1  - Kloock, Joachim P.
A1  - Schöning, Michael Josef
T1  - Novel organic membrane-based thin-film microsensors for the determination of heavy metal cations
N2  - A first step towards the fabrication and electrochemical evaluation of thin-film microsensors based on organic PVC membranes for the determination of Hg(II), Cd(II), Pb(II) and Cu(II) ions in solutions has been realised. The membrane-coating mixture used in the preparation of this new type of microsensors is incorporating PVC as supporting matrix, o-nitrophenyloctylether (o-NPOE) as solvent mediator and a recently synthesized Hg[dimethylglyoxime(phene)]2+ and Bis-(4-hydroxyacetophenone)-ethylenediamine as electroactive materials for Hg(II) and Cd(II), respectively. A set of three commercialised ionophores for Cd(II), Pb(II) and Cu(II) has been also used for comparison. Thin-film microsensors based on these membranes showed a Nernstian response of slope (26-30 mV/dec.) for the respective tested cations. The potentiometric response characteristics (linear range, pH range, detection limit and response time) are comparable with those obtained by conventional membranes as well as coated wire electrodes prepared from the same membrane. The realisation of the new organic membrane-based thin-film microsensors overcomes the problem of an insufficient selectivity of solid-state-based thinfilm sensors.
KW  - Biosensor
KW  - Heavy metal detection
KW  - thin-film microsensors
KW  - organic PVC membranes
Y1  - 2006
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:a96-opus-1545
ER  - 
TY  - JOUR
A1  - Guo, Yuanyuan
A1  - Seki, Kosuke
A1  - Miyamoto, Ko-ichiro
A1  - Wagner, Torsten
A1  - Schöning, Michael Josef
A1  - Yoshinobu, Tatsuo
T1  - Novel photoexcitation method for light-addressable potentiometric sensor with higher spatial resolution
JF  - Applied physics express : APEX
N2  - A novel photoexcitation method for the light-addressable potentiometric sensor (LAPS) is proposed to achieve a higher spatial resolution of chemical images. The proposed method employs a combined light source that consists of a modulated light probe, which generates the alternating photocurrent signal, and a ring of constant illumination surrounding it. The constant illumination generates a sheath of carriers with increased concentration which suppresses the spread of photocarriers by enhanced recombination. A device simulation was carried out to verify the effect of constant illumination on the spatial resolution, which demonstrated that a higher spatial resolution can be obtained.
Y1  - 2014
U6  - http://dx.doi.org/10.7567/APEX.7.067301
SN  - 1882-0786 (E-Journa); 1882-0778 (Print)
VL  - 7
IS  - 6
SP  - 067301-4
PB  - IOP
CY  - Bristol
ER  - 
TY  - JOUR
A1  - Haeger, Gerrit
A1  - Jolmes, Tristan
A1  - Oyen, Sven
A1  - Jaeger, Karl-Erich
A1  - Bongaerts, Johannes
A1  - Schörken, Ulrich
A1  - Siegert, Petra
T1  - Novel recombinant aminoacylase from Paraburkholderia monticola capable of N-acyl-amino acid synthesis
JF  - Applied Microbiology and Biotechnology
N2  - N-Acyl-amino acids can act as mild biobased surfactants, which are used, e.g., in baby shampoos. However, their chemical synthesis needs acyl chlorides and does not meet sustainability criteria. Thus, the identification of biocatalysts to develop greener synthesis routes is desirable. We describe a novel aminoacylase from Paraburkholderia monticola DSM 100849 (PmAcy) which was identified, cloned, and evaluated for its N-acyl-amino acid synthesis potential. Soluble protein was obtained by expression in lactose autoinduction medium and co-expression of molecular chaperones GroEL/S. Strep-tag affinity purification enriched the enzyme 16-fold and yielded 15 mg pure enzyme from 100 mL of culture. Biochemical characterization revealed that PmAcy possesses beneficial traits for industrial application like high temperature and pH-stability. A heat activation of PmAcy was observed upon incubation at temperatures up to 80 °C. Hydrolytic activity of PmAcy was detected with several N-acyl-amino acids as substrates and exhibited the highest conversion rate of 773 U/mg with N-lauroyl-L-alanine at 75 °C. The enzyme preferred long-chain acyl-amino-acids and displayed hardly any activity with acetyl-amino acids. PmAcy was also capable of N-acyl-amino acid synthesis with good conversion rates. The best synthesis results were obtained with the cationic L-amino acids L-arginine and L-lysine as well as with L-leucine and L-phenylalanine. Exemplarily, L-phenylalanine was acylated with fatty acids of chain lengths from C8 to C18 with conversion rates of up to 75%. N-lauroyl-L-phenylalanine was purified by precipitation, and the structure of the reaction product was verified by LC–MS and NMR.
KW  - Chaperone
KW  - Biocatalysis
KW  - Aminoacylase
KW  - Acylation
KW  - Acyl-amino acids
KW  - Biosurfactants
Y1  - 2024
U6  - http://dx.doi.org/10.1007/s00253-023-12868-8
SN  - 1432-0614
N1  - Corresponding author: Petra Siegert
IS  - 108
PB  - Springer
CY  - Berlin
ER  - 
TY  - JOUR
A1  - Iken, Heiko
A1  - Kirsanov, D.
A1  - Legin, A.
A1  - Schöning, Michael Josef
T1  - Novel Thin-Film Polymeric Materials for the Detection of Heavy Metals
JF  - Procedia Engineering
N2  - A variety of transition metals, e.g., copper, zinc, cadmium, lead, etc. are widely used in industry as components for wires, coatings, alloys, batteries, paints and so on. The inevitable presence of transition metals in industrial processes implies the ambition of developing a proper analytical technique for their adequate monitoring. Most of these elements, especially lead and cadmium, are acutely toxic for biological organisms. Quantitative determination of these metals at low activity levels in different environmental and industrial samples is therefore a vital task. A promising approach to achieve an at-side or on-line monitoring on a miniaturized and cost efficient way is the combination of a common potentiometric sensor array with heavy metal-sensitive thin-film materials, like chalcogenide glasses and polymeric materials, respectively.
Y1  - 2012
U6  - http://dx.doi.org/10.1016/j.proeng.2012.09.148
SN  - 1877-7058
N1  - Part of special issue "26th European Conference on Solid-State Transducers, EUROSENSOR 2012"
IS  - 47
SP  - 322
EP  - 325
PB  - Elsevier
CY  - Amsterdam
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  - Zatko, B.
A1  - Dubecký, F.
A1  - Bohacek, P.
A1  - Gombia, E.
A1  - Frigeri, P.
A1  - Mosca, R.
A1  - Franchi, S.
A1  - Huarn, J.
A1  - Nescas, V.
A1  - Sekacova, M.
A1  - Förster, Arnold
A1  - Kordos, P.
T1  - On the spectrometric performance limit of radiation detectors based on semi-insulating GaAs
JF  - Nuclear instruments and methods in physics research, Section A. 531 (2004), H. 1-2
Y1  - 2004
SN  - 0168-9002
SP  - 111
EP  - 120
ER  - 
TY  - JOUR
A1  - Wagner, Torsten
A1  - Beging, Stefan
A1  - Rotter, L.
A1  - Poghossian, Arshak
A1  - Biselli, Manfred
A1  - Zang, Werner
A1  - Schöning, Michael Josef
T1  - Online-Messsysteme für die automatisierte Charakterisierung von feldeffektbasierten Biosensoren
JF  - 8. Dresdner Sensor-Symposium : Sensoren für Umwelt, Klima und Sicherheit, Biosensoren und Biosysteme, Sensoren und Sensorsysteme für die Prozesstechnik, Trends in der Sensortechnik, Materialentwicklung für die Sensorik; 8. Dresdner Sensor-Symposium, 10. - 12. Dezember 2007, Dresden / Gerald Gerlach ... (Hg.)
Y1  - 2007
SN  - 978-3-940046-45-1
N1  - Dresdner Sensor-Symposium <8, 2007, Dresden> ; Dresdner Beiträge zur Sensorik ; 29
SP  - 257
EP  - 260
PB  - TUDpress, Verl. der Wissenschaften
CY  - Dresden
ER  - 
TY  - JOUR
A1  - Kirchner, Patrick
A1  - Oberländer, Jan
A1  - Friedrich, Peter
A1  - Berger, Jörg
A1  - Suso, Henri-Pierre
A1  - Kupyna, Andriy
A1  - Keusgen, Michael
A1  - Schöning, Michael Josef
T1  - Optimisation and fabrication of a calorimetric gas sensor built up on a polyimide substrate for H2O2 monitoring
JF  - Physica status solidi (a) : applications and material science. 208 (2011), H. 6
Y1  - 2011
SN  - 1862-6319
SP  - 1235
EP  - 1240
PB  - Wiley
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  - Dantism, Shahriar
A1  - Röhlen, Desiree
A1  - Wagner, Torsten
A1  - Wagner, Patrick
A1  - Schöning, Michael Josef
T1  - Optimization of Cell-Based Multi-Chamber LAPS Measurements Utilizing FPGA-Controlled Laser-Diode Modules
JF  - physica status solidi a : applications and materials sciences
N2  - A light-addressable potentiometric sensor (LAPS) is a field-effect-based potentiometric device, which detects concentration changes of an analyte solution on the sensor surface in a spatially resolved way. It uses a light source to generate electron–hole pairs inside the semiconductor, which are separated in the depletion region due to an applied bias voltage across the sensor structure and hence, a surface-potential-dependent photocurrent can be read out. However, depending on the beam angle of the light source, scattering effects can occur, which influence the recorded signal in LAPS-based differential measurements. To solve this problem, a novel illumination unit based on a field programmable gate array (FPGA) consisting of 16 small-sized tunable infrared laser-diode modules (LDMs) is developed. Due to the improved focus of the LDMs with a beam angle of only 2 mrad, undesirable scattering effects are minimized. Escherichia coli (E. coli) K12 bacteria are used as a test microorganism to study the extracellular acidification on the sensor surface. Furthermore, a salt bridge chamber is built up and integrated with the LAPS system enabling multi-chamber differential measurements with a single Ag/AgCl reference electrode.
Y1  - 2018
U6  - http://dx.doi.org/10.1002/pssa.201800058
SN  - 1862-6319
VL  - 215
IS  - 15
SP  - Article number 1800058
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Faßbender, F.
A1  - Schmitt, G.
A1  - Schöning, Michael Josef
A1  - Lüth, H.
A1  - Buß, G.
A1  - Schultze, J. W.
T1  - Optimization of passivation layers for corrosion protection of silicon-based microelectrode arrays
JF  - Sensors and Actuators B. 68 (2000), H. 1-3
Y1  - 2000
SN  - 0925-4005
SP  - 128
EP  - 133
ER  - 
TY  - JOUR
A1  - Degering, Christian
A1  - Eggert, Thorsten
A1  - Puls, Michael
A1  - Bongaerts, Johannes
A1  - Evers, Stefan
A1  - Maurer, Karl-Heinz
A1  - Jaeger, Karl-Erich
T1  - Optimization of protease secretion in Bacillus subtilis and Bacillus licheniformis by screening of homologous and herologous signal peptides
JF  - Applied and environmental microbiology
N2  - Bacillus subtilis and Bacillus licheniformis are widely used for the large-scale industrial production of proteins. These strains can efficiently secrete proteins into the culture medium using the general secretion (Sec) pathway. A characteristic feature of all secreted proteins is their N-terminal signal peptides, which are recognized by the secretion machinery. Here, we have studied the production of an industrially important secreted protease, namely, subtilisin BPN′ from Bacillus amyloliquefaciens. One hundred seventy-three signal peptides originating from B. subtilis and 220 signal peptides from the B. licheniformis type strain were fused to this secretion target and expressed in B. subtilis, and the resulting library was analyzed by high-throughput screening for extracellular proteolytic activity. We have identified a number of signal peptides originating from both organisms which produced significantly increased yield of the secreted protease. Interestingly, we observed that levels of extracellular protease were improved not only in B. subtilis, which was used as the screening host, but also in two different B. licheniformis strains. To date, it is impossible to predict which signal peptide will result in better secretion and thus an improved yield of a given extracellular target protein. Our data show that screening a library consisting of homologous and heterologous signal peptides fused to a target protein can identify more-effective signal peptides, resulting in improved protein export not only in the original screening host but also in different production strains.
Y1  - 2010
U6  - http://dx.doi.org/10.1128/AEM.01146-10
SN  - 1098-5336 (E-Journal); 0003-6919 (Print); 0099-2240 (Print)
VL  - 76
IS  - 19
SP  - 6370
EP  - 6378
PB  - American Society for Microbiology
CY  - Washington, DC
ER  - 
TY  - JOUR
A1  - Arreola, Julio
A1  - Mätzkow, Malte
A1  - Durán, Marlena Palomar
A1  - Greeff, Anton
A1  - Keusgen, Michael
A1  - Schöning, Michael Josef
T1  - Optimization of the immobilization of bacterial spores on glass substrates with organosilanes
JF  - Physica status solidi (A) : Applications and materials science
N2  - Spores can be immobilized on biosensors to function as sensitive recognition elements. However, the immobilization can affect the sensitivity and reproducibility of the sensor signal. In this work, three different immobilization strategies with organosilanes were optimized and characterized to immobilize Bacillus atrophaeus spores on glass substrates. Five different silanization parameters were investigated: nature of the solvent, concentration of the silane, silanization time, curing process, and silanization temperature. The resulting silane layers were resistant to a buffer solution (e.g., Ringer solution) with a polysorbate (e.g., Tween®80) and sonication.
KW  - silanization
KW  - organosilanes
KW  - immobilization
KW  - endospores
KW  - biosensors
KW  - Bacillus atrophaeus
Y1  - 2016
U6  - http://dx.doi.org/10.1002/pssa.201532914
SN  - 1862-6319
VL  - 213
IS  - 6
SP  - 1463
EP  - 1470
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Pita, Marcos
A1  - Krämer, Melina
A1  - Zouh, Jian
A1  - Poghossian, Arshak
A1  - Schöning, Michael Josef
A1  - Fernandez, Victor M.
A1  - Katz, Evgeny
T1  - Optoelectronic Properties of Nanostructured Ensembles Controlled by Biomolecular Logic Systems
JF  - ACS Nano. 10 (2008), H. 2
Y1  - 2008
SN  - 1936-086X
SP  - 2160
EP  - 2166
ER  -