04 Fakultät Energie-, Verfahrens- und Biotechnik
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Item Open Access Precision 3D‐printed cell scaffolds mimicking native tissue composition and mechanics(2020) Erben, Amelie; Hörning, Marcel; Hartmann, Bastian; Becke, Tanja; Eisler, Stephan A.; Southan, Alexander; Cranz, Séverine; Hayden, Oliver; Kneidinger, Nikolaus; Königshoff, Melanie; Lindner, Michael; Tovar, Günter E. M.; Burgstaller, Gerald; Clausen‐Schaumann, Hauke; Sudhop, Stefanie; Heymann, MichaelCellular dynamics are modeled by the 3D architecture and mechanics of the extracellular matrix (ECM) and vice versa. These bidirectional cell‐ECM interactions are the basis for all vital tissues, many of which have been investigated in 2D environments over the last decades. Experimental approaches to mimic in vivo cell niches in 3D with the highest biological conformity and resolution can enable new insights into these cell‐ECM interactions including proliferation, differentiation, migration, and invasion assays. Here, two‐photon stereolithography is adopted to print up to mm‐sized high‐precision 3D cell scaffolds at micrometer resolution with defined mechanical properties from protein‐based resins, such as bovine serum albumin or gelatin methacryloyl. By modifying the manufacturing process including two‐pass printing or post‐print crosslinking, high precision scaffolds with varying Young's moduli ranging from 7‐300 kPa are printed and quantified through atomic force microscopy. The impact of varying scaffold topographies on the dynamics of colonizing cells is observed using mouse myoblast cells and a 3D‐lung microtissue replica colonized with primary human lung fibroblast. This approach will allow for a systematic investigation of single‐cell and tissue dynamics in response to defined mechanical and bio‐molecular cues and is ultimately scalable to full organs.Item Open Access Nano-in-micro-particles consisting of PLGA nanoparticles embedded in chitosan microparticles via spray-drying enhances their uptake in the olfactory mucosa(2021) Spindler, Lena Marie; Feuerhake, Andreas; Ladel, Simone; Günday, Cemre; Flamm, Johannes; Günday-Türeli, Nazende; Türeli, Emre; Tovar, Günter E. M.; Schindowski, Katharina; Gruber-Traub, CarmenIntranasal delivery has gained prominence since 1990, when the olfactory mucosa was recognized as the window to the brain and the central nervous system (CNS); this has enabled the direct site specific targeting of neurological diseases for the first time. Intranasal delivery is a promising route because general limitations, such as the blood-brain barrier (BBB) are circumvented. In the treatment of multiple sclerosis (MS) or Alzheimer’s disease, for example, future treatment prospects include specialized particles as delivery vehicles. Poly(lactic-co-glycolic acid) (PLGA) nanoparticles are well known as promising delivery systems, especially in the area of nose-to-brain (N2B) delivery. Chitosan is also broadly known as a functional additive due to its ability to open tight junctions. In this study, we produced PLGA nanoparticles of different sizes and revealed for the first time their size-time-dependent uptake mechanism into the lamina propria of porcine olfactory mucosa. The intracellular uptake was observed for 80 and 175 nm within only 5 min after application to the epithelium. After 15 min, even 520 nm particles were detected, associated with nuclei. Especially the presence of only 520 nm particles in neuronal fibers is remarkable, implying transcellular and intracellular transport via the olfactory or the trigeminal nerve to the brain and the CNS. Additionally, we developed successfully specialized Nano-in-Micro particles (NiMPs) for the first time via spray drying, consisting of PLGA nanoparticles embedded into chitosan microparticles, characterized by high encapsulation efficiencies up to 51%, reproducible and uniform size distribution, as well as smooth surface. Application of NiMPs accelerated the uptake compared to purely applied PLGA nanoparticles. NiMPs were spread over the whole transverse section of the olfactory mucosa within 15 min. Faster uptake is attributed to additional paracellular transport, which was examined via tight-junction-opening. Furthermore, a separate chitosan penetration gradient of ∼150 µm caused by dissociation from PLGA nanoparticles was observed within 15 min in the lamina propria, which was demonstrated to be proportional to an immunoreactivity gradient of CD14. Due to the beneficial properties of the utilized chitosan-derivative, regarding molecular weight (150-300 kDa), degree of deacetylation (80%), and particle size (0.1-10 µm) we concluded that M2-macrophages herein initiated an anti-inflammatory reaction, which seems to already take place within 15 min following chitosan particle application. In conclusion, we demonstrated the possibility for PLGA nanoparticles, as well as for chitosan NiMPs, to take all three prominent intranasal delivery pathways to the brain and the CNS; namely transcellular, intracellular via neuronal cells, and paracellular transport.Item Open Access Physical interactions strengthen chemical gelatin methacryloyl gels(2019) Rebers, Lisa; Granse, Tobias; Tovar, Günter E. M.; Southan, Alexander; Borchers, KirstenChemically cross-linkable gelatin methacryloyl (GM) derivatives are getting increasing attention regarding biomedical applications. Thus, thorough investigations are needed to achieve full understanding and control of the physico-chemical behavior of these promising biomaterials. We previously introduced gelatin methacryloyl acetyl (GMA) derivatives, which can be used to control physical network formation (solution viscosity, sol-gel transition) independently from chemical cross-linking by variation of the methacryloyl-to-acetyl ratio. It is known that temperature dependent physical network formation significantly influences the mechanical properties of chemically cross-linked GM hydrogels. We investigated the temperature sensitivity of GM derivatives with different degrees of modification (GM2, GM10), or similar degrees of modification but different methacryloyl contents (GM10, GM2A8). Rheological analysis showed that the low modified GM2 forms strong physical gels upon cooling while GM10 and GM2A8 form soft or no gels. Yet, compression testing revealed that all photo cross-linked GM(A) hydrogels were stronger if cooling was applied during hydrogel preparation. We suggest that the hydrophobic methacryloyl and acetyl residues disturb triple helix formation with increasing degree of modification, but additionally form hydrophobic structures, which facilitate chemical cross-linking.Item Open Access Patterns of autologous and nonautologous interactions between core nuclear egress complex (NEC) proteins of α-, β- and γ-herpesviruses(2020) Häge, Sigrun; Sonntag, Eric; Borst, Eva Maria; Tannig, Pierre; Seyler, Lisa; Bäuerle, Tobias; Bailer, Susanne M.; Lee, Chung-Pei; Müller, Regina; Wangen, Christina; Milbradt, Jens; Marschall, ManfredNuclear egress is a regulated process shared by α-, β- and γ-herpesviruses. The core nuclear egress complex (NEC) is composed of the membrane-anchored protein homologs of human cytomegalovirus (HCMV) pUL50, murine cytomegalovirus (MCMV) pM50, Epstein-Barr virus (EBV) BFRF1 or varicella zoster virus (VZV) Orf24, which interact with the autologous NEC partners pUL53, pM53, BFLF2 or Orf27, respectively. Their recruitment of additional proteins leads to the assembly of a multicomponent NEC, coordinately regulating viral nucleocytoplasmic capsid egress. Here, the functionality of VZV, HCMV, MCMV and EBV core NECs was investigated by coimmunoprecipitation and confocal imaging analyses. Furthermore, a recombinant MCMV, harboring a replacement of ORF M50 by UL50, was analyzed both in vitro and in vivo. In essence, core NEC interactions were strictly limited to autologous NEC pairs and only included one measurable nonautologous interaction between the homologs of HCMV and MCMV. A comparative analysis of MCMV-WT versus MCMV-UL50-infected murine fibroblasts revealed almost identical phenotypes on the levels of protein and genomic replication kinetics. In infected BALB/c mice, virus spread to lung and other organs was found comparable between these viruses, thus stating functional complementarity. In conclusion, our study underlines that herpesviral core NEC proteins are functionally conserved regarding complementarity of core NEC interactions, which were found either virus-specific or restricted within subfamilies.Item Open Access The microalgae phaeodactylum tricornutum Is well suited as a food with positive effects on the intestinal microbiota and the generation of SCFA : results from a pre-clinical study(2022) Stiefvatter, Lena; Neumann, Ulrike; Rings, Andreas; Frick, Konstantin; Schmid-Staiger, Ulrike; Bischoff, Stephan C.Microalgae such as Phaeodactylum tricornutum (PT) are a sustainable source of nutrients, especially eicosapentaenoic acid (EPA), fucoxanthin (Fx), and chrysolaminarin (Chrl), the concentrations of which can vary depending on the culture conditions. We generated three types of diets containing either an EPA- and Fx-rich (EPA/Fx) or Chrl-rich microalgae (with 5, 15, or 25% added to the diet) or an isocaloric control diet (CD). These diets were evaluated over 14 days in young C57BL/6J mice for safety and bioavailability, short-chain fatty acid (SCFA) production, and microbiome analysis. Both microalgae diets increased body weight gain dose-dependently compared to the CD. Microalgae-derived EPA was well absorbed, resulting in increased liver and fat tissue levels and a decrease in the n-6:n-3 ratio in liver tissue. Both microalgae diets increased the production of selected SCFA and decreased the Firmicutes/Bacteriodota ratio, whereas the Chrl-rich diet led to an increase in Akkermansia. Doses of up to 4621 mg Chrl, 920 mg EPA, and 231 mg Fx per kg body weight daily were tolerated without adverse effects. This pre-clinical study shows that PT is suitable for mouse feed, with positive effects on microbiota composition and SCFA production, suggesting beneficial effects on gut health.Item Open Access Factors affecting the synthesis of cellobiose lipids by Sporisorium scitamineum(2020) Oraby, Amira; Werner, Nicole; Sungur, Zehra; Zibek, SusanneCellobiose lipids (CL) are extracellular glycolipids that are produced by many microorganisms from the family Ustilaginaceae. The sugarcane smut fungus Sporisorium scitamineum has been long known as a producer of the glycolipids mannosylerythritol lipids (MEL) and was recently described to additionally secrete CL as a byproduct. In fact, we identified 11 homologous genes in S. scitamineum by in silico analysis sharing a high similarity to the CL biosynthesis gene cluster of Ustilago maydis. We here report the first systematic cultivation of S. scitamineum targeting the synthesis of CL with high product titers and its transfer to the bioreactor. In an initial screening we examined different fermentation media compositions, consisting of a mineral salts solution with vitamins and/or trace elements, three carbon sources (glucose, fructose, sucrose), three pH values (2.5, 4.0, 6.7) and three levels of C/N values (42.2, 83.8, 167.2 molC molN -1) with urea as nitrogen source. A pH of 2.5 proved to result in the highest product titers. An increase of urea concentration from 0.6 to 1.2 g L-1 had a positive effect on biomass formation, however the glycolipid formation was favored at a C/N ratio of 83.8 molC molN -1, using 0.6 g L-1 urea. Amongst the examined carbon sources, sucrose resulted in an increase in the secretion of cellobiose lipids, compared to glucose. Comparing different media compositions, vitamins were identified as not necessary for CL synthesis. We obtained a concentration of cellobiose lipids of 8.3 1.0 g L-1 in shaking flasks. This increased to 17.6 g L-1 in the 1 L bioreactor with additional feeding of carbon source, with a final purity of 85-93%. As a side product, erythritol and mannosylerythritol lipids (MEL) were also synthesized. Via HPTLC coupled MALDI-TOF MS we were able to analyze the secreted CL structures. S. scitamineum produces a mixture of acylated low molecular weight D-glucolipids, linked to a 2,15,16-trihydroxy-hexadecanoic acid via their &-hydroxyl group (CL-B). The produced cellobiose lipids precipitate as needle like crystals at an acidic pH value of 2.5.Item Open Access Etablierung einer biologischen vaskularisierten Matrix als Grundlage für ein in-vitro-Lebertestsystem(2007) Schanz, Johanna Elisabeth; Brunner, Herwig (Prof. Dr. techn.)Die Leber spielt eine zentrale Rolle im Stoffwechsel eines Organismus. Sie ist aus einer Vielzahl hochspezialisierter Zellen aufgebaut und übernimmt komplexe, für den gesamten Organismus lebensnotwendige Stoffwechselfunktionen. Eingenommene Medikamente und Substanzen gelangen im Menschen über das Blutkreislaufsystem zur Leber und werden dort von den Hepatozyten um- und abgebaut (Biotransformation). Hierbei entstehen sogenannte Metabolite, die oft eine ganz andere (mitunter toxische) Wirkung haben als das ursprüngliche Medikament. Aus diesem Grund sind Leberzellen (Hepatozyten) bzw. das gesamte Organ "Leber" von besonderem Interesse als Analysesystem für Substanzen, Wirkstoffe und ihre Metabolite. Es gibt für Metabolismusstudien verschiedene, relativ einfache in vitro Testsysteme jedoch noch kein humanes organähnliches Lebermodell, das Langzeitstudien an primären Hepatozyten ohne Funktionsverlust ermöglicht. Damit isolierte Hepatozyten in der Kultur ihre Funktionalität behalten, ist die Bereitstellung einer möglichst in vivo ähnlichen Mikroumgebung wichtig. Dazu gehören einerseits die Co-Kultur mit nicht-parenchymalen Leberzellen und andererseits die Gewährleistung der Zellversorgung sowie eine geeignete Trägerstruktur (Matrix), die eine 3-Dimensionalität der Kultur schafft. Zur Aufbau eines Co-Kultursystems wurden in dieser Arbeit Endothelzellen eingesetzt, da sie eine Filtrationsbarriere für Makromoleküle zwischen dem Blut und den Gewebszellen bilden und an der Regenerationsprozessen beteiligt sind. Als Trägerstruktur wurde eine azellularisierte, vaskularisierte Matrix aus Schweinedarm, das so genannte "Biological Vascularized Scaffold" (BioVaSc), verwendet. Sie basiert auf einem 10 - 15 cm langen Stück porcinen Jejunums, welches sich unter Erhalt der Gefäßsystemstrukturen inklusive des arteriellen Zuflusses sowie des venösen Abflusses chemisch azellularisieren lässt. Eine ausreichende Versorgung der Hepatozyten mit Nährstoffen und Sauerstoff sowie der Abtransport von Toxinen und Metaboliten nach Medikamenten-/Wirkstoff-Umsetzung ließen sich durch ein computergesteuertes Bioreaktorsystem gewährleisten. Zum Aufbau eines Lebermoduls wurde die BioVaSc in zwei Schritten mit Zellen besiedelt: Im ersten Schritt erfolgte die Rebesiedelung der Gefäßstrukturen mit primären mikrovaskulären Endothelzellen oder endothelialen Vorläufer über den arteriellen Zufluss. Im zweiten Besiedlungsschritt folgte die Besiedlung des Matrixlumens (ehemaliger Darm) mit primären Hepatozyten. Dazu wurden die Zellen in einer Kollagen-I-Suspension ins Matrixlumen pipettiert und selbiges an beiden Seiten mit Klemmen verschlossen. Das so entstandene Co-Kultursystem ließ sich über einen Zeitraum von 2-3 Wochen im Bioreaktor kultivieren. Eine Probenentnahme zur Überwachung der Zellfunktionen erfolgte wochentäglich. Nach Versuchsende fand eine Fixierung der BioVaSc für die Herstellung von Paraffinpräparaten statt. Anhand der Expression der endothelzellspezifischen Marker CD 31 und FLK-1 konnte im Rahmen dieser Arbeit die Differenzierung porciner Vorläuferzellen aus dem Knochenmark in Endothelzellen nachgewiesen werden. Humane Endothelzellen ließen sich unter Erhalt der genannten Marker in das Gefäßsystem integrieren und waren der Ursprung für neu entstandene Blutgefäße (Neoangiogenese). Die ins System integrierten Hepatozyten exprimierten ebenfalls zellspezifische Marker (CKLP 34, Hepatocyte), bildeten wichtige Zell-Zellkontakte wie Tight Junctions und Adherens Junctions aus und proliferierten. Durch die Anfärbung von Tight Junctions ließen sich zwischen den Zellen Gallenkanälchenstrukturen sichtbar machen. Eine Kommunikation zwischen Endothelzellen und Hepatozyten (cellular Cross-Talk) konnte über die Expression von Vascular Endothelial Growth Factor (VEGF) belegt werden. Anhand der Mediumproben ließ sich nachgeweisen, dass die Hepatozyten bis zum Ende der Kultur Harnstoff sowie Albumin synthetisierten und Laktat bildeten. Der Phase-I- und Phase-II-Metabolismus von Dextrometorphan war im porcinen Modell ohne Enzyminduktion nachweisbar. Die Etablierung des Lebermoduls erfolgte zunächst aufgrund der besseren Verfügbarkeit auf Basis porciner Zellen. Die Ergebnisse ließen sich jedoch anschließend auf das humane Modell übertragen. In dieser Arbeit konnte gezeigt werden, dass sich die BioVaSc als Grundlage für ein Lebertestsystem eignet. Das hier aufgebaute System hat als erstes Modell ein Gefäßsystem zur Co-Kultur von Endothelzellen und Hepatozyten unter physiologischen Bedingungen. Erstmals stellt ein Lebermodell damit die Möglichkeit in Aussicht den Transport von im Blut gelösten Molekülen durch die sinusoidale Endothelzellschicht zu den Hepatozyten bzw. von Metaboliten durch die sinusoidale Endothelzellschicht zum Blut zu untersuchen.Item Open Access Influence of light conditions on the production of chrysolaminarin using Phaeodactylum tricornutum in artificially illuminated photobioreactors(2023) Frick, Konstantin; Ebbing, Tobias; Yeh, Yen‐Cheng; Schmid‐Staiger, Ulrike; Tovar, Günter E. M.The light conditions are of utmost importance in any microalgae production process especially involving artificial illumination. This also applies to a chrysolaminarin (soluble 1,3-β-glucan) production process using the diatom Phaeodactylum tricornutum. Here we examine the influence of the amount of light per gram biomass (specific light availability) and the influence of two different biomass densities (at the same amount of light per gram biomass) on the accumulation of the storage product chrysolaminarin during nitrogen depletion in artificially illuminated flat-panel airlift photobioreactors. Besides chrysolaminarin, other compounds (fucoxanthin, fatty acids used for energy storage [C16 fatty acids], and eicosapentaenoic acid) are regarded as well. Our results show that the time course of C-allocation between chrysolaminarin and fatty acids, serving as storage compounds, is influenced by specific light availability and cell concentration. Furthermore, our findings demonstrate that with increasing specific light availability, the maximal chrysolaminarin content increases. However, this effect is limited. Beyond a certain specific light availability (here: 5 µmolphotons gDW-1 s-1) the maximal chrysolaminarin content no longer increases, but the rate of increase becomes faster. Furthermore, the conversion of light to chrysolaminarin is best at the beginning of nitrogen depletion. Additionally, our results show that a high biomass concentration has a negative effect on the maximal chrysolaminarin content, most likely due to the occurring self-shading effects.Item Open Access New insights into structure and function of type I collagen(2008) Xiong, Xin; Brunner, Herwig (Prof. Dr. techn.)Collagen is one of the most abundant proteins in mammalians and strongly conserved throughout evolution. It constitutes one third of the human proteome and comprises three-quarters of the dry weight of human skin. It is widely accepted as a major structural component in animal body such as in bones, cartilage and skins. More and more studies have shown that, in addition to the structural function, collagens can induce or regulate many cellular functions and processes such as cell differentiation, cell motion, cell communication and apoptosis. Furthermore, its unique triple helix structure gained more attention since it is responsible for its high stability and biological function. Due to the high accessibility, Type I and Type III collagen are widely studied and frequently used as biocompatible materials in cell culture, tissue engineering and medical technology. Until now the understanding of the molecular mechanisms for collagen assembly is of great medical and also biotechnological importance. Here, large amounts of highly purified homogeneous Type I collagen have been obtained from rat tail tendon by a simple two-step purification involving extraction with 9 M urea followed by Superose 12 chromatography. This simple two step purification of Type I collagen is up-scalable. The yield is up to 95%. The product could be easily lyophilized and stored. AFM and SEM images showed a structure similar to natural collagen. This collagen was extensively characterized by different biochemical, physical and cell biological methods. Mass spectrometry identified only collagen Type I peptides indicating that the extracted collagen was homogeneous. The comparison between urea-extracted (UC) collagen and acetic acid-extracted collagen (AC) showed significant differences whereby the UC was not degraded or hydrolyzed as in acetic acid. Furthermore, tandem MS analyses showed some interesting post-translational modifications, which will result in new insights into collagen structure in vivo. The purified collagen was renatured quantitatively by dialysis against water to form triple-helices, as judged by UV-circular dichroism. The collagen dissolved in 8M urea exhibits a unique reversible aggregation behavior which is not affected by the presence of reducing agents. UV-circular dichroism analysis shows that collagen initiates triple helix formation at 4 M urea or below. This triple helix structure is comparable to that observed with synthetic collagen peptides. Cultures of a 3T3 mouse embryonic fibroblast cells incubated with urea-extracted collagen showed a higher motility than those grown with acetic acid-extracted collagen as judged by light microscopy and scanning electron microscopy. The real time PCR showed significant difference on transcriptional level and showed clearly up regulation of the genes involved in response to mechanical stress in AC but not in UC and reference culture in medium. All these results indicate a benefit of UC for biotechnological/biomedical applications. The urea-extracted collagen exhibits a unique reversible-aggregational phenomenon during gel filtration in 8 M urea. We could show that covalent bonds and cross-linkings are not involved. This observation and subsequently extensive mass spectrometric analyses led to a new model of triple-helical assembly and a hypothesis about the collagen export, which may offer some new insights into understanding of collagen structure and transport from cytosol to extracellular space. The results presented here have led to an industrial patent (patented on 04. 30th. 2008). A manuscript was submitted to FEBS J for publication.Item Open Access Phänotypische und molekularbiologische Untersuchungen der Interaktionen in gemischten Biofilmen(2012) Purschke, Frauke Gina; Rupp, Steffen (PD Dr.)Die Mehrheit der Mikroorganismen lebt in ihrer natürlichen Umgebung in Biofilmen, oberflächenassoziierten Lebensgemeinschaften, die normalerweise von einer extra-zellulären Matrix umgeben sind. Die meisten Biofilme werden nicht von einzelnen sondern mehreren Spezies gebildet, die in den Biofilmen nicht nur miteinander kooperieren, sondern auch um vorhandene Nährstoffe konkurrieren. Die Gram-negative Bakterienspezies Pseudomonas aeruginosa und der polymorphe Pilz Candida albicans sind zwei opportunistisch Pathogene, die oft in Co-Existenz in einem humanen Wirt nachgewiesen werden. Verschiedene Modelle antagonistischen Verhaltens wurden für diese Organismen in gemischten Biofilmen berichtet. Um diese Inter-aktionen zwischen P. aeruginosa und C. albicans genauer zu erforschen, wurde der Einfluss der Quorum sensing Moleküle untersucht. Hierfür wurde ein in vitro Assay etabliert, der eine einfache und schnelle Detektion von Veränderungen in der Aus-prägung von Biofilmen erlaubt. Während sowohl Überstände als auch nur das für die Biofilmbildung von P. aeruginosa wichtige Quorum sensing Molekül N-3-oxo-dodecanoyl-homoserinlacton die Biofilmbildung von C. albicans unterdrücken, wirkt Farnesol, der Pilz-Autoinducer, zwar inhibierend auf die Adhärenz, aber verstärkend auf bereits bestehende bakterielle Biofilme. Zur weiteren Charakteriserung dieser Interaktion wurde das Sekretom einzelner und gemischter Biofilme zu verschiedenen Zeitpunkten mit MALDI-TOF MS/MS analysiert. Insgesamt wurden 247 unter-schiedliche Proteine identifiziert, von denen 170 P. aeruginosa und 77 C. albicans zugeordnet werden konnten. P. aeruginosa sekretierte in Anwesenheit von C. albicans Virulenzfaktoren wie das Exotoxin A sowie Proteine der Stoffwechselwege zur Eisenerfassung wie das Pyochelin-Biosynthese-Protein PchD und den Ferripyoverdin-Rezeptor FpvA. Außerdem wurde in gemischten Biofilmen jedoch nicht in rein bakteriellen Biofilmen das Siderophor Pyoverdin identifiziert, das Eisen mit großer Affinität bindet. Dieses deutet darauf hin, dass P. aeruginosa in Konkurrenz mit C. albicans die Wege zur Eisenaufnahme induziert. Von C. albicans dagegen wird der Metabolismus reprimiert, inklusive der detektierten eisenbindenden Proteine. Diese Ergebnisse zeigen, dass Mikroorganismen nicht nur mit dem Wirt um essentielle Nährstoffe konkurrieren, sondern auch mit der vorhandenen Mikroflora. Die transkriptionellen Veränderungen während der Ausbildung von Biofilmen wurden genutzt, um Reporterstämme in C. albicans, P. aeruginosa und dem nicht-pathogenen E. coli herzustellen, welche die Bildung von Biofilmen anzeigen. Mit Hilfe dieser Stämme können Quorum sensing Moleküle anderer Mikroorganismen detektiert werden. Gemeinsam mit dem in vitro Assay steht mit diesen Stämmen eine Toolbox zur Verfügung, um Biofilme und Einflüsse auf diese zu charakterisieren.