@article{DigelAkimbekovRogachevetal.2023, author = {Digel, Ilya and Akimbekov, Nuraly S. and Rogachev, Evgeniy and Pogorelova, Natalia}, title = {Bacterial cellulose produced by Medusomyces gisevii on glucose and sucrose: biosynthesis and structural properties}, series = {Cellulose}, journal = {Cellulose}, publisher = {Springer Science + Business Media}, address = {Dordrecht}, issn = {1572-882X (Online)}, doi = {10.1007/s10570-023-05592-z}, pages = {15 Seiten}, year = {2023}, abstract = {In this work, the effects of carbon sources and culture media on the production and structural properties of bacterial cellulose (BC) synthesized by Medusomyces gisevii have been studied. The culture medium was composed of different initial concentrations of glucose or sucrose dissolved in 0.4\% extract of plain green tea. Parameters of the culture media (titratable acidity, substrate conversion degree etc.) were monitored daily for 20 days of cultivation. The BC pellicles produced on different carbon sources were characterized in terms of biomass yield, crystallinity and morphology by field emission scanning electron microscopy (FE-SEM), atomic force microscopy and X-ray diffraction. Our results showed that Medusomyces gisevii had higher BC yields in media with sugar concentrations close to 10 g L-1 after a 18-20 days incubation period. Glucose in general lead to a higher BC yield (173 g L-1) compared to sucrose (163.5 g L-1). The BC crystallinity degree and surface roughness were higher in the samples synthetized from sucrose. Obtained FE-SEM micrographs show that the BC pellicles synthesized in the sucrose media contained densely packed tangles of cellulose fibrils whereas the BC produced in the glucose media displayed rather linear geometry of the BC fibrils without noticeable aggregates.}, language = {en} } @article{HaegerWirgesTanzmannetal.2023, author = {Haeger, Gerrit and Wirges, Jessika and Tanzmann, Nicole and Oyen, Sven and Jolmes, Tristan and Jaeger, Karl-Erich and Sch{\"o}rken, Ulrich and Bongaerts, Johannes and Siegert, Petra}, title = {Chaperone assisted recombinant expression of a mycobacterial aminoacylase in Vibrio natriegens and Escherichia coli capable of N-lauroyl-L-amino acid synthesis}, series = {Microbial Cell Factories}, journal = {Microbial Cell Factories}, number = {22}, publisher = {Springer Nature}, issn = {1475-2859}, doi = {10.1186/s12934-023-02079-1}, pages = {Article number: 77 (2023)}, year = {2023}, abstract = {Background Aminoacylases are highly promising enzymes for the green synthesis of acyl-amino acids, potentially replacing the environmentally harmful Schotten-Baumann reaction. Long-chain acyl-amino acids can serve as strong surfactants and emulsifiers, with application in cosmetic industries. Heterologous expression of these enzymes, however, is often hampered, limiting their use in industrial processes. Results We identified a novel mycobacterial aminoacylase gene from Mycolicibacterium smegmatis MKD 8, cloned and expressed it in Escherichia coli and Vibrio natriegens using the T7 overexpression system. The recombinant enzyme was prone to aggregate as inclusion bodies, and while V. natriegens Vmax™ could produce soluble aminoacylase upon induction with isopropyl β-d-1-thiogalactopyranoside (IPTG), E. coli BL21 (DE3) needed autoinduction with lactose to produce soluble recombinant protein. We successfully conducted a chaperone co-expression study in both organisms to further enhance aminoacylase production and found that overexpression of chaperones GroEL/S enhanced aminoacylase activity in the cell-free extract 1.8-fold in V. natriegens and E. coli. Eventually, E. coli ArcticExpress™ (DE3), which co-expresses cold-adapted chaperonins Cpn60/10 from Oleispira antarctica, cultivated at 12 °C, rendered the most suitable expression system for this aminoacylase and exhibited twice the aminoacylase activity in the cell-free extract compared to E. coli BL21 (DE3) with GroEL/S co-expression at 20 °C. The purified aminoacylase was characterized based on hydrolytic activities, being most stable and active at pH 7.0, with a maximum activity at 70 °C, and stability at 40 °C and pH 7.0 for 5 days. The aminoacylase strongly prefers short-chain acyl-amino acids with smaller, hydrophobic amino acid residues. Several long-chain amino acids were fairly accepted in hydrolysis as well, especially N-lauroyl-L-methionine. To initially evaluate the relevance of this aminoacylase for the synthesis of N-acyl-amino acids, we demonstrated that lauroyl-methionine can be synthesized from lauric acid and methionine in an aqueous system. Conclusion Our results suggest that the recombinant enzyme is well suited for synthesis reactions and will thus be further investigated.}, language = {en} } @article{FalkenbergKohnBottetal.2023, author = {Falkenberg, Fabian and Kohn, Sophie and Bott, Michael and Bongaerts, Johannes and Siegert, Petra}, title = {Biochemical characterisation of a novel broad pH spectrum subtilisin from Fictibacillus arsenicus DSM 15822ᵀ}, series = {FEBS Open Bio}, volume = {13}, journal = {FEBS Open Bio}, number = {11}, publisher = {Wiley}, address = {Hoboken, NJ}, issn = {2211-5463}, doi = {10.1002/2211-5463.13701}, pages = {2035 -- 2046}, year = {2023}, abstract = {Subtilisins from microbial sources, especially from the Bacillaceae family, are of particular interest for biotechnological applications and serve the currently growing enzyme market as efficient and novel biocatalysts. Biotechnological applications include use in detergents, cosmetics, leather processing, wastewater treatment and pharmaceuticals. To identify a possible candidate for the enzyme market, here we cloned the gene of the subtilisin SPFA from Fictibacillus arsenicus DSM 15822ᵀ (obtained through a data mining-based search) and expressed it in Bacillus subtilis DB104. After production and purification, the protease showed a molecular mass of 27.57 kDa and a pI of 5.8. SPFA displayed hydrolytic activity at a temperature optimum of 80 °C and a very broad pH optimum between 8.5 and 11.5, with high activity up to pH 12.5. SPFA displayed no NaCl dependence but a high NaCl tolerance, with decreasing activity up to concentrations of 5 m NaCl. The stability enhanced with increasing NaCl concentration. Based on its substrate preference for 10 synthetic peptide 4-nitroanilide substrates with three or four amino acids and its phylogenetic classification, SPFA can be assigned to the subgroup of true subtilisins. Moreover, SPFA exhibited high tolerance to 5\% (w/v) SDS and 5\% H₂O₂ (v/v). The biochemical properties of SPFA, especially its tolerance of remarkably high pH, SDS and H₂O₂, suggest it has potential for biotechnological applications.}, language = {en} } @article{FalkenbergVossBottetal.2023, author = {Falkenberg, Fabian and Voß, Leonie and Bott, Michael and Bongaerts, Johannes and Siegert, Petra}, title = {New robust subtilisins from halotolerant and halophilic Bacillaceae}, series = {Applied Microbiology and Biotechnology}, volume = {107}, journal = {Applied Microbiology and Biotechnology}, publisher = {Springer Nature}, address = {Berlin}, issn = {1432-0614}, doi = {10.1007/s00253-023-12553-w}, pages = {3939 -- 3954}, year = {2023}, abstract = {The aim of the present study was the characterisation of three true subtilisins and one phylogenetically intermediate subtilisin from halotolerant and halophilic microorganisms. Considering the currently growing enzyme market for efficient and novel biocatalysts, data mining is a promising source for novel, as yet uncharacterised enzymes, especially from halophilic or halotolerant Bacillaceae, which offer great potential to meet industrial needs. Both halophilic bacteria Pontibacillus marinus DSM 16465ᵀ and Alkalibacillus haloalkaliphilus DSM 5271ᵀ and both halotolerant bacteria Metabacillus indicus DSM 16189 and Litchfieldia alkalitelluris DSM 16976ᵀ served as a source for the four new subtilisins SPPM, SPAH, SPMI and SPLA. The protease genes were cloned and expressed in Bacillus subtilis DB104. Purification to apparent homogeneity was achieved by ethanol precipitation, desalting and ion-exchange chromatography. Enzyme activity could be observed between pH 5.0-12.0 with an optimum for SPPM, SPMI and SPLA around pH 9.0 and for SPAH at pH 10.0. The optimal temperature for SPMI and SPLA was 70 °C and for SPPM and SPAH 55 °C and 50 °C, respectively. All proteases showed high stability towards 5\% (w/v) SDS and were active even at NaCl concentrations of 5 M. The four proteases demonstrate potential for future biotechnological applications.}, language = {en} } @masterthesis{Doblas2023, type = {Bachelor Thesis}, author = {Doblas, Miguel}, title = {Electrovisuals : Auditive Eigenschaften elektronischer Musik infografisch interpretiert}, publisher = {FH Aachen}, address = {Aachen}, school = {Fachhochschule Aachen}, year = {2023}, abstract = {Elektronische Musik umgibt uns alle. Der Einfluss elektronischer Musikproduktion auf moderne Popularmusik ist nicht von der Hand zu weisen und ihre Produktionstechniken f{\"u}r heutige Standards unverzichtbar. {\"U}ber die Jahre ihrer Entwicklung und den dabei entstandenen Musikrichtungen verschwanden die individuellen Charakteristika der verschiedenen Subgenres allerdings oft einfach unter der Sammelbezeichnung elektronischer Musik. »Electrovisuals« stellt die auditiven Eigenschaften elektronischer Musik in Form von klaren Infografiken dar und sorgt damit f{\"u}r ein besseres Verst{\"a}ndnis von Rhythmus und Struktur der Songs. Die verschiedenen Subgenres werden multimedial inszeniert und einander gegen{\"u}bergestellt, um {\"A}hnlichkeiten und Unterschiede zu betonen. Mithilfe seiner Aufbereitung stellt das Projekt die hohe Diversit{\"a}t elektronischer Musik heraus und bereitet sie eindrucksvoll und greifbar auf.}, language = {de} } @masterthesis{Tappert2023, type = {Bachelor Thesis}, author = {Tappert, Celine}, title = {Die Zukunft des Energiemanagements : ein modulares Konzept und Design f{\"u}r verschiedene Nutzergruppen.}, publisher = {FH Aachen}, address = {Aachen}, school = {Fachhochschule Aachen}, pages = {251 Seiten}, year = {2023}, abstract = {Enma ist eine Energiemanagement-Anwendung, die verschiedene Nutzer:innengruppen zusammenf{\"u}hrt und damit den Prozess vereinfacht. Die aktuelle Energiekrise betrifft insbesondere Unternehmen, die in der Energieerzeugung t{\"a}tig sind. Die Digitalisierung wird f{\"u}r Unternehmen in der Zukunft immer wichtiger und sie werden sich ihr nicht entziehen k{\"o}nnen. Daher ben{\"o}tigen insbesondere Unternehmen, die keinen dedizierten Energiemanager:innen besch{\"a}ftigen, gezielte Unterst{\"u}tzung von Anwendungen. Auch Vertriebspartner:innen und Hersteller:innen von Produkten wie PV-Anlagen und Stromspeichern, die von solch einer Anwendung profitieren k{\"o}nnen, wollen ihren Kunden:innen Sicherheit und Unterst{\"u}tzung bieten. Daf{\"u}r ist eine Anwendung erforderlich, die dies vereint. Das Ziel war es, das Backend von OpenEMS (Energiemanagementsystems) zu nutzen und zus{\"a}tzlich einen menschenzentrierten und umweltfreundlichen Ansatz zu bieten. Um die Anwendung realistischer zu gestalten, wurde sie in Kooperation mit dem Unternehmen Voltfang entwickelt.}, language = {de} } @masterthesis{Shafaghi2023, type = {Bachelor Thesis}, author = {Shafaghi, Shiva}, title = {Zan, Zendegi, Azadi}, publisher = {FH Aachen}, address = {Aachen}, school = {Fachhochschule Aachen}, pages = {66 Seiten}, year = {2023}, abstract = {Das Projekt „Zan, Zendegi, Azadi" (Frau, Leben, Freiheit) setzt sich mit der aktuellen Situation im Iran auseinander. Bereits nach der Macht{\"u}bernahme der islamischen Republik im Jahr 1979 wird die iranische Bev{\"o}lkerung durch das brutale Regime unterdr{\"u}ckt und zum Schweigen gezwungen. Dieser Druck hat sich lange aufgestaut und nun gibt es seit Jahren in gr{\"o}ßeren Abst{\"a}nden Proteste gegen die Regierung. Der gewaltsame Tod der kurdischen Iranerin Mahsā J{\^i}na Amīnī in Polizeigewahrsam am 16.09.2022 hat eine beispiellose Welle des Protests in allen Landesteilen Irans ausgel{\"o}st. Ihr Protest wird von Frauen angef{\"u}hrt und hat sich in eine beeindruckende Welle des Widerstands und der Rebellion entwickelt. Die unterschiedlichen Medien in diesem Projekt wie Dokumentarfotografie, Illustration, Projektion und Texte geben Betrachter:innen einen Eindruck der unmittelbaren Wirkung der revolution{\"a}ren Ereignisse und der Reaktion des totalit{\"a}ren Regimes auf die Betroffenen.}, language = {de} } @article{GrajewskiKleefeld2023, author = {Grajewski, Matthias and Kleefeld, Andreas}, title = {Detecting and approximating decision boundaries in low-dimensional spaces}, series = {Numerical Algorithms}, volume = {93}, journal = {Numerical Algorithms}, number = {4}, publisher = {Springer Science+Business Media}, address = {Dordrecht}, issn = {1572-9265}, pages = {35 Seiten}, year = {2023}, abstract = {A method for detecting and approximating fault lines or surfaces, respectively, or decision curves in two and three dimensions with guaranteed accuracy is presented. Reformulated as a classification problem, our method starts from a set of scattered points along with the corresponding classification algorithm to construct a representation of a decision curve by points with prescribed maximal distance to the true decision curve. Hereby, our algorithm ensures that the representing point set covers the decision curve in its entire extent and features local refinement based on the geometric properties of the decision curve. We demonstrate applications of our method to problems related to the detection of faults, to multi-criteria decision aid and, in combination with Kirsch's factorization method, to solving an inverse acoustic scattering problem. In all applications we considered in this work, our method requires significantly less pointwise classifications than previously employed algorithms.}, language = {en} } @masterthesis{Dorn2023, type = {Bachelor Thesis}, author = {Dorn, Aileen Sakura}, title = {Effizienz und Gesundheitsf{\"o}rderung im Krankenhaus : Dienstplanung im Krankenhaus unter Ber{\"u}cksichtigung der berufsbedingten psychischen und physischen Gesundheit des Klinikpersonals}, publisher = {FH Aachen}, address = {Aachen}, school = {Fachhochschule Aachen}, pages = {133 Seiten}, year = {2023}, abstract = {Dass der Stress im Krankenhaus eine Belastung f{\"u}r das Klinikpersonal darstellt, ist eine allseits bekannte Tatsache. Das liegt an dem anstrengenden Klinikalltag, welcher die Mitarbeiter:innen auf Belastungsprobe stellt. Lange Dienste und {\"U}berstunden, wenig Pausen und hohe Arbeitsverdichtung, Nacht- und Schichtdienst, zudem auch die aufwendige Dokumentation und ̈B{\"u}rokratie. Timewise behandelt die Thematik der Dienstplanerstellung im Krankenhaus unter der Ber{\"u}cksichtigung der psychischen und physischen Gesundheit des Klinikpersonals im Nacht- und Schichtdienst. Essenzielle Funktionen sind k{\"u}rzere Kommunikationswege und eine gute {\"U}bersicht {\"u}ber den Soll-Ist-Abgleich inklusive {\"U}berstunden, Minusstunden, Abwesenheiten und den monatlichen Lohn. Der einfache Schichttausch und die Option der Ber{\"u}cksichtigung individueller Präferenzen und W{\"u}nsche ermöglicht es dem Personal, die Arbeit und das private Leben besser miteinander vereinen zu können, was sich positiv auf die Arbeitszufriedenheit auswirkt.}, language = {de} } @masterthesis{Oezmen2023, type = {Bachelor Thesis}, author = {{\"O}zmen, Emel}, title = {ALIGN : ein adaptives Regalsystem}, publisher = {FH Aachen}, address = {Aachen}, school = {Fachhochschule Aachen}, pages = {119 Seiten}, year = {2023}, abstract = {„ALIGN" ist ein smartes M{\"o}belsystem, das den individuellen Lebensstil und die Werte der heutigen Gesellschaft widerspiegelt. Es bietet ausreichend Stauraum und erm{\"o}glicht es, Objekte gezielt in Szene zu setzen oder in den Hintergrund zu r{\"u}cken. Das vielseitige System passt sich an unterschiedliche Raum- und Nutzungsszenarien an. Es erm{\"o}glicht die individuelle Gestaltung des Wohnraums nach pers{\"o}nlichen Vorlieben und hilft, den Herausforderungen des modernen Lebens gerecht zu werden. „ALIGN" - eine passende L{\"o}sung f{\"u}r jedes Problem.}, language = {de} }