@article{BerndtKrueger1985,
  author    = {Berndt, Heinz and Kr{\"u}ger, G{\"o}tz},
  title     = {Resolution of enantiomeric amino acid derivatives by high-performance liquid chromatography on chiral stationary phases},
  series = {Journal of chromatography A},
  volume    = {1985},
  journal   = {Journal of chromatography A},
  number    = {348},
  issn      = {0021-9673},
  doi       = {10.1016/S0021-9673(01)92461-6},
  pages     = {275 -- 279},
  year      = {1985},
  language  = {en}
}
@inproceedings{SiekerDuwePothetal.2012,
  author    = {Sieker, T. and Duwe, A. and Poth, S. and Tippk{\"o}tter, Nils and Ulber, Roland},
  title     = {Herstellung von Itacons{\"a}ure aus Buchenholzhydrolysaten},
  series = {Kurzfassungsband / GVC-DECHEMA Vortrags- und Diskussionstagung Biopharmazeutische Produktion : 14. - 16. Mai 2012. Konzerthaus Freibung},
  booktitle = {Kurzfassungsband / GVC-DECHEMA Vortrags- und Diskussionstagung Biopharmazeutische Produktion : 14. - 16. Mai 2012. Konzerthaus Freibung},
  publisher = {DECHEMA},
  address   = {Frankfurt, M.},
  pages     = {57},
  year      = {2012},
  language  = {de}
}
@article{MeyerStorkKalbeKuropkaetal.1988,
  author    = {Meyer-Stork, L. Sebastian and Kalbe, Jochen and Kuropka, Rolf and Sauter, S. L. and H{\"o}cker, Hartwig and Berndt, Heinz},
  title     = {Eindeutige Provenienzanalyse von Wolle und feinen Tierhaaren mit Hilfe der Erbsubstanz (DNS)},
  series = {Textilveredlung : schweizerische Zeitschrift f{\"u}r Textilchemie, Textilveredlung und deren Randgebiete},
  volume    = {23},
  journal   = {Textilveredlung : schweizerische Zeitschrift f{\"u}r Textilchemie, Textilveredlung und deren Randgebiete},
  number    = {9},
  issn      = {0040-5310},
  pages     = {304 -- 307},
  year      = {1988},
  language  = {de}
}
@article{SchnabelSchnabelBerndt1971,
  author    = {Schnabel, Eugen and Schnabel, Henning and Berndt, Heinz},
  title     = {Zur selektiven acidolytischen Abspaltbarkeit der tert.-Butyloxycarbonyl-Gruppe},
  series = {Justus Liebigs Annalen der Chemie},
  volume    = {749},
  journal   = {Justus Liebigs Annalen der Chemie},
  number    = {1},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  issn      = {1099-0690},
  doi       = {10.1002/jlac.19717490111},
  pages     = {90 -- 108},
  year      = {1971},
  abstract  = {Die tert.-Butyloxycarbonyl-Gruppe (Boc) l{\"a}ßt sich mittels reiner Trifluoressigs{\"a}ure nicht selektiv neben dem Benzyloxycarbonyl-Rest (Z) abspalten. Das gelingt auch nicht mit L{\"o}sungen von Trifluoressigs{\"a}ure bzw. Chlorwasserstoff in organischen L{\"o}sungsmitteln. Kern-substituierte Z-Gruppen wie Z(pCl), Z(mCl) oder Z(pNO₂) sind zwar stabiler, werden aber von den obengenannten Reagenzien ebenfalls angegriffen bzw. sind nicht mehr acidolytisch abspaltbar. - Mit 70proz. w{\"a}ßriger Trifluoressigs{\"a}ure gelingt die Abspaltung von Boc neben Z dagegen fast selektiv; dabei werden aber Benzylester, besonders Glutamins{\"a}ure-γ-benzylester, teilweise hydrolysiert, w{\"a}hrend Methyl- sowie {\"A}thylester nahezu best{\"a}ndig sind. Die Brauchbarkeit des Abspaltungsverfahrens wird anhand der schrittweise durchgef{\"u}hrten Synthese zweier Heptapeptid-Derivate gezeigt. - {\"A}hnlich spezifisch gelingt die Abspaltung von Boc mit Bortrifluorid-{\"a}therat in Eisessig; Benzylester sind gegen{\"u}ber diesem Reagenz stabiler als gegen w{\"a}ßrige Trifluoressigs{\"a}ure. Das Bortrifluorid-Verfahren eignet sich besonders f{\"u}r die Abspaltung von Boc-Gruppen neben s{\"a}urelabilen Thiol-Schutzgruppen (Tetrahydropyranyl- bzw. Trityl-Rest) sowie neben dem Cyclocystinyl-Rest. Die Leistungsf{\"a}higkeit der Methode wird durch die Synthese zweier Peptid-Derivate mit S-Trityl-Schutzgruppen belegt. Als Nebenreaktion ist die Acetylierung von aliphatischen Hydroxylgruppen m{\"o}glich. Sie l{\"a}ßt sich vermeiden, wenn man die Spaltung in anderen L{\"o}sungsmitteln durchf{\"u}hrt. Die als Modellverbindungen f{\"u}r Stabilit{\"a}tsuntersuchungen verwendeten Nε-acylierten Lysin-Derivate werden mit dem Aminos{\"a}ureanalysator quantitativ neben Lysin bestimmt.},
  language  = {de}
}
@article{KuropkaMuellerHoeckeretal.1989,
  author    = {Kuropka, Rolf and M{\"u}ller, Bettina and H{\"o}cker, Hartwig and Berndt, Heinz},
  title     = {Chiral stationary phases via hydrosilylation reaction of N-acryloylamino acids : I. Stationary phase with one chiral centre for high-performance liquid chromatography and development of a new derivatization pattern for amino acid enantiomers},
  series = {Journal of chromatography A},
  journal   = {Journal of chromatography A},
  number    = {481},
  isbn      = {0021-9673},
  pages     = {380 -- 386},
  year      = {1989},
  language  = {en}
}
@article{NokiharaBerndt1978,
  author    = {Nokihara, Kiyoshi and Berndt, Heinz},
  title     = {Studies on sulfur-containing peptides : tert-butyloxycarbonylsulfenyl and benzyloxycarbonylsulfenyl derivatives as protecting groups for cysteine},
  series = {The journal of organic chemistry},
  volume    = {43},
  journal   = {The journal of organic chemistry},
  number    = {25},
  publisher = {American Chemical Society},
  address   = {Washington},
  issn      = {0022-3263},
  doi       = {10.1021/jo00419a046},
  pages     = {4893 -- 4895},
  year      = {1978},
  language  = {en}
}
@article{KalbeHoeckerBerndt1989,
  author    = {Kalbe, Jochen and H{\"o}cker, Hartwig and Berndt, Heinz},
  title     = {Design of enzyme reactors as chromatographic columns for racemic resolution of amino acid esters},
  series = {Chromatographia},
  volume    = {28},
  journal   = {Chromatographia},
  number    = {3-4},
  isbn      = {0009-5893},
  doi       = {10.1007/BF02319646},
  pages     = {193 -- 196},
  year      = {1989},
  language  = {en}
}
@article{TurckBerndt1981,
  author    = {Turck, Christoph W. and Berndt, Heinz},
  title     = {Synthese definierter Peptid-Derivate durch Aminolyse von 3-(Nα-Acyl-peptidyloxy)-2-hydroxy-N-alkylbenzamiden bei erh{\"o}hten Temperaturen, I : Synthese des Modellpeptid-Derivates Z-Ala-Phe-Gly-N(Et)2},
  series = {Hoppe-Seyler´s Zeitschrift f{\"u}r physiologische Chemie},
  volume    = {362},
  journal   = {Hoppe-Seyler´s Zeitschrift f{\"u}r physiologische Chemie},
  number    = {1},
  issn      = {1437-4315},
  doi       = {10.1515/bchm2.1981.362.1.821},
  pages     = {821 -- 828},
  year      = {1981},
  language  = {de}
}
@article{DanhoNaithaniSasakietal.1980,
  author    = {Danho, Waleed and Naithani, Vinod K. and Sasaki, Andr{\´e} N. and F{\"o}hles, Joseph and Berndt, Heinz and B{\"u}llesbach, Erika E. and Zahn, H.},
  title     = {Human proinsulin, VII : synthesis of two protected peptides corresponding to the sequences 1—45 and 46—86 of the prohormone},
  series = {Hoppe-Seyler's Zeitschrift f{\"u}r physiologische Chemie},
  volume    = {361},
  journal   = {Hoppe-Seyler's Zeitschrift f{\"u}r physiologische Chemie},
  number    = {1},
  issn      = {1437-4315},
  doi       = {10.1515/bchm2.1980.361.1.857},
  pages     = {857 -- 863},
  year      = {1980},
  language  = {en}
}
@article{KalbeKuropkaMeyerStorketal.1988,
  author    = {Kalbe, Jochen and Kuropka, Rolf and Meyer-Stork, L. Sebastian and Berndt, Heinz and Sauter, Sybille L. and Loss, Peter and Hendo, Karsten and Riesner, Detlev and H{\"o}cker, Hartwig},
  title     = {Isolation and characterization of high-molecular mass DNA from hair shafts},
  series = {Biological chemistry},
  volume    = {369},
  journal   = {Biological chemistry},
  number    = {1},
  isbn      = {0177-3593},
  doi       = {10.1515/bchm3.1988.369.1.413},
  pages     = {413 -- 416},
  year      = {1988},
  language  = {en}
}
@article{BaumannTillmannAletsee1989,
  author    = {Baumann, Marcus and Tillmann, Urban and Aletsee, Ludwig},
  title     = {Distribution of Carbon Among Photosynthetic End Products in the Bloom-Forming Arctic Diatom Thalassiosira antarctica COMBER / Tillmann, U. ; Baumann, M.E.M. ; Aletsee, L.},
  series = {Polar Biology. 10 (1989), H. 3},
  journal   = {Polar Biology. 10 (1989), H. 3},
  isbn      = {0722-4060},
  pages     = {231 -- 238},
  year      = {1989},
  language  = {en}
}
@inproceedings{AlKaidyUlberTippkoetter2014,
  author    = {Al-Kaidy, Huschyar and Ulber, Roland and Tippk{\"o}tter, Nils},
  title     = {A platform technology for the automated reaction control in magnetizable micro-fluidic droplets},
  series = {Biomaterials - made in bioreactors : book of abstracts, May 26 - 28, 2014, Radisson Blu Park Hotel and Conference Dentre, Radebeul, Germany},
  booktitle = {Biomaterials - made in bioreactors : book of abstracts, May 26 - 28, 2014, Radisson Blu Park Hotel and Conference Dentre, Radebeul, Germany},
  publisher = {DECHEMA},
  address   = {Frankfurt am Main},
  pages     = {21 -- 22},
  year      = {2014},
  language  = {en}
}
@masterthesis{Kobus2014,
  type      = {Bachelor Thesis},
  author    = {Kobus, Timm},
  title     = {Untersuchung des unterschiedlichen Reduktionsverhaltens von unterschiedlich para-substituierten Acetophenonen mit Chiralidon R \& S},
  school      = {Fachhochschule Aachen},
  pages     = {128 S.},
  year      = {2014},
  language  = {de}
}
@misc{KowollikSchnitzlerBisellietal.2010,
  author    = {Kowollik, Silvia and Schnitzler, Thomas and Biselli, Manfred and Krueger, R. and Zang, Werner and Peuscher, A. and Schillberg, S. and Fischer, R.},
  title     = {Die Rolle des Respirationsquotienten in der Zellkulturfermentation},
  series = {Chemie Ingenieur Technik},
  volume    = {82},
  journal   = {Chemie Ingenieur Technik},
  number    = {9},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  isbn      = {Chemie Ingenieur Tec},
  doi       = {10.1002/cite.201050393},
  pages     = {1505 -- 1506},
  year      = {2010},
  abstract  = {In der biopharmazeutischen Industrie werden rekombinante Proteine und monoklonale Antik{\"o}rper in Zellkulturfermentationen produziert, da nur humane oder tierische Zelllinien {\"u}ber die F{\"a}higkeit der Glykosylierung verf{\"u}gen. Um hohe Produktausbeuten in ausgezeichneter Qualit{\"a}t zu erzielen, ist eine funktionst{\"u}chtige Prozesskontrolle unerl{\"a}sslich. Hierzu wurde in Kooperation mit der Firma Hitec Zang GmbH die HiSense� Pr{\"a}zisionsabgasanalytik entwickelt, die auf Basis der vollautomatischen Ermittlung des Respirationsquotienten (RQ; Verh{\"a}ltnis vonKohlendioxidbildungsrate (CER) zu Sauerstoffaufnahmerate (OTR)) einen Fermentationsprozess nicht-invasiv {\"u}berwacht. Der RQ kann in Hybridoma- und CHO-Zellen (s. Abb.) in sowohl serumhaltigen als auch serumfreien Medien erfolgreich ermittelt werden. Hier spiegeln die CER und die OTR das Wachstumsverhalten der kultivierten CHO-Zellen wider. Der RQ nimmt dabei Werte zwischen 0,9 und 1,2 an. Dies l{\"a}sst auf verschiedene Stoffwechselaktivit{\"a}ten schließen. Da die momentane industrielle Prozesskontrolle auf gemessenen Sauerstoffaufnahmeraten oder entsprechende Offline-Analytiken der Metaboliten basieren, soll durch die vollautomatische RQ-Ermittlung ein neues Verfahren zur Fermentations{\"u}berwachung etabliert werden. Bisher war diese, in bakteriellen Kultivierungen standardisierte Methode, aufgrund der schwierigen CER-Berechnung bei Zellkulturen keine ad{\"a}quate Alternative.},
  language  = {de}
}
@article{RibitschHeumannKarletal.2012,
  author    = {Ribitsch, Doris and Heumann, Sonja and Karl, Wolfgang and Gerlach, Jochen and Leber, Regina and Birner-Gruenberger, Ruth and Gruber, Karl and Eiteljoerg, Inge and Remler, Peter and Siegert, Petra and Lange, Jennifer and Maurer, Karl-Heinz and Berg, Gabriele and Guebitz, G. M. and Schwab, H.},
  title     = {Extracellular serine proteases from Stenotrophomonas maltophilia: Screening, isolation and heterologous expression in E. coli},
  series = {Journal of biotechnology},
  volume    = {157},
  journal   = {Journal of biotechnology},
  number    = {1},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {1873-4863 (E-Journal); 0168-1656 (Print)},
  doi       = {10.1016/j.jbiotec.2011.09.025},
  pages     = {140 -- 147},
  year      = {2012},
  abstract  = {A large strain collection comprising antagonistic bacteria was screened for novel detergent proteases. Several strains displayed protease activity on agar plates containing skim milk but were inactive in liquid media. Encapsulation of cells in alginate beads induced protease production. Stenotrophomonas maltophilia emerged as best performer under washing conditions. For identification of wash-active proteases, four extracellular serine proteases called StmPr1, StmPr2, StmPr3 and StmPr4 were cloned. StmPr2 and StmPr4 were sufficiently overexpressed in E. coli. Expression of StmPr1 and StmPr3 resulted in unprocessed, insoluble protein. Truncation of most of the C-terminal domain which has been identified by enzyme modeling succeeded in expression of soluble, active StmPr1 but failed in case of StmPr3. From laundry application tests StmPr2 turned out to be a highly wash-active protease at 45 °C. Specific activity of StmPr2 determined with suc-l-Ala-l-Ala-l-Pro-l-Phe-p-nitroanilide as the substrate was 17 ± 2 U/mg. In addition we determined the kinetic parameters and cleavage preferences of protease StmPr2.},
  language  = {en}
}
@article{SrivastavaSinghAggarwaletal.2010,
  author    = {Srivastava, Alok and Singh, Virendra and Aggarwal, Pranav and Schneeweiss, F. and Scherer, Ulrich W. and Friedrich, W.},
  title     = {Optical studies of insulating polymers for radiation dose monitoring},
  series = {Indian Journal of Pure and Applied Physics},
  volume    = {48},
  journal   = {Indian Journal of Pure and Applied Physics},
  number    = {11},
  publisher = {Council Of Scientific And Industrial Research (CSIR), National Institute Of Science Communication and Policy Research (NIScPR)},
  address   = {New Delhi},
  isbn      = {0019-5596},
  pages     = {782 -- 786},
  year      = {2010},
  abstract  = {The optical study carried out on insulating polymers namely polyethyleneterephthalate (PET) and polyvinylchloride (PVC) has been described. The polymers are exposed to different radiation doses by exposing them to swift heavy ions of carbon (90 MeV), silicon (120 MeV) and nickel (100 MeV) which influence on their optical properties. The studies show that amongst the investigated polymers, PVC and PET have potential for application as dosimeter beyond a threshold dose which is strongly dependent on the nature of the material and the radiation type. The optical micrographs show a distinct change in colour of the sample with increase in radiation dose.},
  language  = {en}
}
@inproceedings{EngelThieringerTippkoetter2016,
  author    = {Engel, Mareike and Thieringer, Julia and Tippk{\"o}tter, Nils},
  title     = {Linking bioprocess engineering and electrochemistry for sustainable biofuel production},
  series = {Young Researchers Symposium, YRS 2016. Proceedings},
  booktitle = {Young Researchers Symposium, YRS 2016. Proceedings},
  publisher = {Fraunhofer Verlag},
  address   = {Karlsruhe},
  pages     = {49 -- 53},
  year      = {2016},
  abstract  = {Electromicrobial engineering is an emerging, highly interdisciplinary research area linking bioprocesses with electrochemistry. In this work, microbial electrosynthesis (MES) of biobutanol is carried out during acetone-butanol-ethanol (ABE) fermentations with Clostridium acetobutylicum. A constant electric potential of -600mV (vs. Ag/AgCl) with simultaneous addition of the soluble redox mediator neutral red is used in order to study the electron transfer between the working electrode and the bacterial cells. The results show an earlier initiation of solvent production for all fermentations with applied potential compared to the conventional ABE fermentation. The f inal butanol concentration can be more than doubled by the application of a negative potential combined with addition of neutral red. Moreover a higher biofilm formation on the working electrode compared to control cultivations has been observed. In contrast to previous studies, our results also indicate that direct electron transfer (DET) might be possible with C. acetobutylicum. The presented results make microbial butanol production economically attractive and therefore support the development of sustainable production processes in the chemical industry aspired by the "Centre for resource-efficient chemistry and raw material change" as well as the the project "NanoKat" working on nanostructured catalysts in Kaiserslautern.},
  language  = {en}
}
@article{OehlenschlaegerVolkmarStiefelmaieretal.2024,
  author    = {Oehlenschl{\"a}ger, Katharina and Volkmar, Marianne and Stiefelmaier, Judith and Langsdorf, Alexander and Holtmann, Dirk and Tippk{\"o}tter, Nils and Ulber, Roland},
  title     = {New insights into the influence of pre-culture on robust solvent production of C. acetobutylicum},
  series = {Applied Microbiology and Biotechnology},
  volume    = {108},
  journal   = {Applied Microbiology and Biotechnology},
  publisher = {Springer},
  address   = {Berlin, Heidelberg},
  issn      = {1432-0614},
  doi       = {10.1007/s00253-023-12981-8},
  pages     = {10 Seiten},
  year      = {2024},
  abstract  = {Clostridia are known for their solvent production, especially the production of butanol. Concerning the projected depletion of fossil fuels, this is of great interest. The cultivation of clostridia is known to be challenging, and it is difficult to achieve reproducible results and robust processes. However, existing publications usually concentrate on the cultivation conditions of the main culture. In this paper, the influence of cryo-conservation and pre-culture on growth and solvent production in the resulting main cultivation are examined. A protocol was developed that leads to reproducible cultivations of Clostridium acetobutylicum. Detailed investigation of the cell conservation in cryo-cultures ensured reliable cell growth in the pre-culture. Moreover, a reason for the acid crash in the main culture was found, based on the cultivation conditions of the pre-culture. The critical parameter to avoid the acid crash and accomplish the shift to the solventogenesis of clostridia is the metabolic phase in which the cells of the pre-culture were at the time of inoculation of the main culture; this depends on the cultivation time of the pre-culture. Using cells from the exponential growth phase to inoculate the main culture leads to an acid crash. To achieve the solventogenic phase with butanol production, the inoculum should consist of older cells which are in the stationary growth phase. Considering these parameters, which affect the entire cultivation process, reproducible results and reliable solvent production are ensured.},
  language  = {en}
}
@article{HengsbachEngelCwienczeketal.2023,
  author    = {Hengsbach, Jan-Niklas and Engel, Mareike and Cwienczek, Marcel and Stiefelmaier, Judith and Tippk{\"o}tter, Nils and Ulber, Roland},
  title     = {Scalable unseparated bioelectrochemical reactors by using a carbon fiber brush as stirrer and working electrode},
  series = {ChemElectroChem},
  volume    = {10},
  journal   = {ChemElectroChem},
  number    = {21},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  issn      = {2196-0216},
  doi       = {10.1002/celc.202300440},
  pages     = {9 Seiten},
  year      = {2023},
  abstract  = {The concept of energy conversion into platform chemicals using bioelectrochemical systems (BES) has gained increasing attention in recent years, as the technology simultaneously provides an opportunity for sustainable chemical production and tackles the challenge of Power-to-X technologies. There are many approaches to realize the industrial scale of BES. One concept is to equip standard bioreactors with static electrodes. However, large installations resulted in a negative influence on various reactor parameters. In this study, we present a new single-chamber BES based on a stirred tank reactor in which the stirrer was replaced by a carbon fiber brush, performing the functions of the working electrode and the stirrer. The reactor is characterized in abiotic studies and electro-fermentations with Clostridium acetobutylicum. Compared to standard reactors an increase in butanol production of 20.14±3.66 \% shows that the new BES can be efficiently used for bioelectrochemical processes.},
  language  = {en}
}
@article{HaegerProbstJaegeretal.2023,
  author    = {Haeger, Gerrit and Probst, Johanna and Jaeger, Karl-Erich and Bongaerts, Johannes and Siegert, Petra},
  title     = {Novel aminoacylases from Streptomyces griseus DSM 40236 and their recombinant production in Streptomyces lividans},
  series = {FEBS Open Bio},
  volume    = {13},
  journal   = {FEBS Open Bio},
  number    = {12},
  publisher = {Wiley},
  address   = {Hoboken, NJ},
  issn      = {2211-5463},
  doi       = {10.1002/2211-5463.13723},
  pages     = {2224 -- 2238},
  year      = {2023},
  abstract  = {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.},
  language  = {en}
}