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- ItemGenotyping of methicillin resistant Staphylococcus aureus from the United Arab Emirates([London] : Macmillan Publishers Limited, part of Springer Nature, 2020) Senok, Abiola; Nassar, Rania; Celiloglu, Handan; Nabi, Anju; Alfaresi, Mubarak; Weber, Stefan; Rizvi, Irfan; Müller, Elke; Reissig, Annett; Gawlik, Darius; Monecke, Stefan; Ehricht, RalfReports from Arabian Gulf countries have demonstrated emergence of novel methicillin resistant Staphylococcus aureus (MRSA) strains. To address the lack of data from the United Arab Emirates (UAE), genetic characterisation of MRSA identified between December 2017 and August 2019 was conducted using DNA microarray-based assays. The 625 MRSA isolates studied were grouped into 23 clonal complexes (CCs) and assigned to 103 strains. CC5, CC6, CC22 and CC30 represented 54.2% (n/N = 339/625) of isolates with other common CCs being CC1, CC8, CC772, CC361, CC80, CC88. Emergence of CC398 MRSA, CC5-MRSA-IV Sri Lanka Clone and ST5/ST225-MRSA-II, Rhine-Hesse EMRSA/New York-Japan Clone in our setting was detected. Variants of pandemic CC8-MRSA-[IVa + ACME I] (PVL+) USA300 were detected and majority of CC772 strains were CC772-MRSA-V (PVL+), “Bengal- Bay Clone”. Novel MRSA strains identified include CC5-MRSA-V (edinA+), CC5-MRSA-[VT + fusC], CC5-MRSA-IVa (tst1+), CC5-MRSA-[V/VT + cas + fusC + ccrA/B-1], CC8-MRSA-V/VT, CC22-MRSA-[IV + fusC + ccrAA/(C)], CC45-MRSA-[IV + fusC + tir], CC80-MRSA-IVa, CC121-MRSA-V/VT, CC152-MRSA-[V + fusC] (PVL+). Although several strains harboured SCC-borne fusidic acid resistance (fusC) (n = 181), erythromycin/clindamycin resistance (ermC) (n = 132) and gentamicin resistance (aacA-aphD) (n = 179) genes, none harboured vancomycin resistance genes while mupirocin resistance gene mupR (n = 2) and cfr gene (n = 1) were rare. An extensive MRSA repertoire including CCs previously unreported in the region and novel strains which probably arose locally suggest an evolving MRSA landscape. © 2020, The Author(s).
- ItemMolecular investigations on a chimeric strain of Staphylococcus aureus sequence type 80(San Francisco, California, US : PLOS, 2020) Gawlik, Darius; Ruppelt-Lorz, Antje; Müller, Elke; Reißig, Annett; Hotzel, Helmut; Braun, Sascha D.; Söderquist, Bo; Ziegler-Cordts, Albrecht; Stein, Claudia; Pletz, Mathias W.; Ehricht, Ralf; Monecke, StefanA PVL-positive, methicillin-susceptible Staphylococcus aureus was cultured from pus from cervical lymphadenitis of a patient of East-African origin. Microarray hybridisation assigned the isolate to clonal complex (CC) 80 but revealed unusual features, including the presence of the ORF-CM14 enterotoxin homologue and of an ACME-III element as well as the absence of etD and edinB. The isolate was subjected to both, Illumina and Nanopore sequencing allowing characterisation of deviating regions within the strain´s genome. Atypical features of this strain were attributable to the presence of two genomic regions that originated from other S. aureus lineages and that comprised, respectively, 3% and 1.4% of the genome. One deviating region extended from walJ to sirB. It comprised ORF-CM14 and the ACME-III element. A homologous but larger fragment was also found in an atypical S. aureus CC1/ST567 strain whose lineage might have served as donor of this genomic region. This region itself is a chimera comprising fragments from CC1 as well as fragments of unknown origin. The other deviating region comprised the region from htsB to ecfA2, i.e., another 3% of the genome. It was very similar to CC1 sequences. Either this suggests an incorporation of CC1 DNA into the study strain, or alternatively a recombination event affecting “canonical” CC80. Thus, the study strain bears witness of several recombination events affecting supposedly core genomic genes. Although the exact mechanism is not yet clear, such chimerism seems to be an additional pathway in the evolution of S. aureus. This could facilitate also a transmission of virulence and resistance factors and therefore offer an additional evolutionary advantage.
- ItemMagnetic domain wall gratings for magnetization reversal tuning and confined dynamic mode localization([London] : Macmillan Publishers Limited, part of Springer Nature, 2016) Trützschler, Julia; Sentosun, Kadir; Mozooni, Babak; Mattheis, Roland; McCord, JeffreyHigh density magnetic domain wall gratings are imprinted in ferromagnetic-antiferromagnetic thin films by local ion irradiation by which alternating head-to-tail-to-head-to-tail and head-to-head-to-tail-to-tail spatially overlapping domain wall networks are formed. Unique magnetic domain processes result from the interaction of anchored domain walls. Non-linear magnetization response is introduced by the laterally distributed magnetic anisotropy phases. The locally varying magnetic charge distribution gives rise to localized and guided magnetization spin-wave modes directly constrained by the narrow domain wall cores. The exchange coupled multiphase material structure leads to unprecedented static and locally modified dynamic magnetic material properties.
- ItemResponse of the wood-decay fungus Schizophyllum commune to co-occurring microorganisms(San Francisco, California, US : PLOS, 2020) Krause, Katrin; Jung, Elke-Martina; Lindner, Julia; Hardiman, Imam; Petschner, Jessica; Madhavan, Soumya; Matthäus, Christian; Kai, Marco; Menezes, Riya Christina; Popp, Jürgen; Svatoš, Aleš; Kothe, ErikaMicroorganisms are constantly interacting in a given environment by a constant exchange of signaling molecules. In timber, wood-decay fungi will come into contact with other fungi and bacteria. In naturally bleached wood, dark, pigmented lines arising from confrontation of two fungi often hint at such interactions. The metabolites (and pigment) exchange was investigated using the lignicolous basidiomycete Schizophyllum commune, and co-occurring fungi and bacteria inoculated directly on sterilized wood, or on media. In interactions with competitive wood degrading fungi, yeasts or bacteria, different competition strategies and communication types were observed, and stress reactions, as well as competitor-induced enzymes or pigments were analyzed. Melanin, indole, flavonoids and carotenoids were shown to be induced in S. commune interactions. The induced genes included multi-copper oxidases lcc1, lcc2, mco1, mco2, mco3 and mco4, possibly involved in both pigment production and lignin degradation typical for wood bleaching by wood-decay fungi.
- ItemImmune mobilising T cell receptors redirect polyclonal CD8+ T cells in chronic HIV infection to form immunological synapses([London] : Macmillan Publishers Limited, part of Springer Nature, 2022) Wallace, Zoë; Kopycinski, Jakub; Yang, Hongbing; McCully, Michelle L.; Eggeling, Christian; Chojnacki, Jakub; Dorrell, LucyT cell exhaustion develops in human immunodeficiency virus (HIV) infection due to chronic viral antigenic stimulation. This adaptive response primarily affects virus-specific CD8+ T cells, which may remain dysfunctional despite viral load-reducing antiretroviral therapy; however, abnormalities may also be evident in non-HIV-specific populations. Both could limit the efficacy of cell therapies against viral reservoirs. Here, we show that bulk (polyclonal) CD8+ T cells from people living with HIV (PLWH) express proposed markers of dysfunctional HIV-specific T cells at high levels yet form lytic immunological synapses (IS) and eliminate primary resting infected (HIV Gaglo) CD4+ T cells, when redirected by potent bispecific T cell-retargeting molecules, Immune mobilising monoclonal T cell receptors (TCR) Against Virus (ImmTAV). While PLWH CD8+ T cells are functionally impaired when compared to CD8+ T cells from HIV-naïve donors, ImmTAV redirection enables them to eliminate Gaglo CD4+ T cells that are insensitive to autologous HIV-specific cytolytic T cells. ImmTAV molecules may therefore be able to target HIV reservoirs, which represent a major barrier to a cure.
- ItemLaser spectroscopic technique for direct identification of a single virus I: FASTER CARS(Washington, DC : National Acad. of Sciences, 2020) Deckert, Volker; Deckert-Gaudig, Tanja; Cialla-May, Dana; Popp, Jürgen; Zell, Roland; Deinhard-Emmer, Stefanie; Sokolov, Alexei V.; Yi, Zhenhuan; Scully, Marlan O.From the famous 1918 H1N1 influenza to the present COVID-19 pandemic, the need for improved viral detection techniques is all too apparent. The aim of the present paper is to show that identification of individual virus particles in clinical sample materials quickly and reliably is near at hand. First of all, our team has developed techniques for identification of virions based on a modular atomic force microscopy (AFM). Furthermore, femtosecond adaptive spectroscopic techniques with enhanced resolution via coherent anti-Stokes Raman scattering (FASTER CARS) using tip-enhanced techniques markedly improves the sensitivity [M. O. Scully, et al, Proc. Natl. Acad. Sci. U.S.A. 99, 10994-11001 (2002)].
- ItemFiber-based 3D nano-printed holography with individually phase-engineered remote points([London] : Macmillan Publishers Limited, part of Springer Nature, 2022) Plidschun, Malte; Zeisberger, Matthias; Kim, Jisoo; Wieduwilt, Torsten; Schmidt, Markus A.The generation of tailored light fields with spatially controlled intensity and phase distribution is essential in many areas of science and application, while creating such patterns remotely has recently defined a key challenge. Here, we present a fiber-compatible concept for the remote generation of complex multi-foci three-dimensional intensity patterns with adjusted relative phases between individual foci. By extending the well-known Huygens principle, we demonstrate, in simulations and experiments, that our interference-based approach enables controlling of both intensity and phase of individual focal points in an array of spots distributed in all three spatial directions. Holograms were implemented using 3D nano-printing on planar substrates and optical fibers, showing excellent agreement between design and implemented structures. In addition to planar substrates, holograms were also generated on modified single-mode fibers, creating intensity distributions consisting of about 200 individual foci distributed over multiple image planes. The presented scheme yields an innovative pathway for phase-controlled 3D digital holography over remote distances, yielding an enormous potential application in fields such as quantum technology, life sciences, bioanalytics and telecommunications. Overall, all fields requiring precise excitation of higher-order optical resonances, including nanophotonics, fiber optics and waveguide technology, will benefit from the concept.
- ItemObservation of direction instability in a fiber ring laser([London] : Macmillan Publishers Limited, part of Springer Nature, 2021) Arshad, Muhammad Assad; Hartung, Alexander; Pratiwi, Arni Candra; Jäger, MatthiasWe report on the observation of a new phenomenon occurring in a fiber ring laser. This phenomenon is about the transition from an initially bidirectional emission of a reciprocal fiber ring laser to a unidirectional emission at a certain pump power threshold. In addition, the final direction is not predefined but appears to be randomly chosen every time the threshold is exceeded. Therefore, we term this new phenomenon direction instability. Furthermore, we provide a first discussion of how the instability threshold is influenced by the length and the loss of the cavity. We show that the threshold follows a power times length scaling, indicating a nonlinear origin.
- ItemDevelopment of a miniaturized protein microarray as a new serological IgG screening test for zoonotic agents and production diseases in pigs(San Francisco, California, US : PLOS, 2019) Loreck, Katharina; Mitrenga, Sylvia; Meemken, Diana; Heinze, Regina; Reissig, Annett; Mueller, Elke; Ehricht, Ralf; Engemann, Claudia; Greiner, MatthiasIn order to monitor the occurrence of zoonotic agents in pig herds as well as to improve herd health management, the development of new cost-effective diagnostic methods for pigs is necessary. In this study, a protein microarray-based assay for the simultaneous detection of immunoglobulin G (IgG) antibodies against different zoonotic agents and pathogens causing production diseases in pigs was developed. Therefore, antigens of ten different important swine pathogens (Toxoplasma gondii, Yersinia enterocolitica, Salmonella spp., Trichinella spp., Mycobacterium avium, Hepatitis E virus, Mycoplasma hyopneumoniae, Actinobacillus pleuropneumoniae, the porcine reproductive and respiratory syndrome virus, Influenza A virus) were spotted and covalently immobilized as ‘antigen-spots’ on microarray chips in order to test pig serum for the occurrence of antibodies. Pig serum was sampled at three German abattoirs and ELISA tests for the different pathogens were conducted with the purpose of creating a panel of reference samples for microarray analysis. To evaluate the accuracy of the antigens on the microarray, receiver operating characteristic (ROC) curve analysis using the ELISA test results as reference was performed for the different antigens. High area under curve values were achieved for the antigens of two zoonotic agents: Toxoplasma gondii (0.91), Yersinia enterocolitica (0.97) and for three production diseases: Actinobacillus pleuropneumoniae (0.77), Mycoplasma hyopneumoniae (0.94) and the porcine reproductive and respiratory syndrome virus (0.87). With the help of the newly developed microarray assay, collecting data on the occurrence of antibodies against zoonotic agents and production diseases in pig herds could be minimized to one measurement, resulting in an efficient screening test.
- ItemGiant refractometric sensitivity by combining extreme optical Vernier effect and modal interference([London] : Macmillan Publishers Limited, part of Springer Nature, 2020) Gomes, André D.; Kobelke, Jens; Bierlich, Jörg; Dellith, Jan; Rothhardt, Manfred; Bartelt, Hartmut; Frazão, OrlandoThe optical Vernier effect consists of overlapping responses of a sensing and a reference interferometer with slightly shifted interferometric frequencies. The beating modulation thus generated presents high magnified sensitivity and resolution compared to the sensing interferometer, if the two interferometers are slightly out of tune with each other. However, the outcome of such a condition is a large beating modulation, immeasurable by conventional detection systems due to practical limitations of the usable spectral range. We propose a method to surpass this limitation by using a few-mode sensing interferometer instead of a single-mode one. The overlap response of the different modes produces a measurable envelope, whilst preserving an extremely high magnification factor, an order of magnification higher than current state-of-the-art performances. Furthermore, we demonstrate the application of that method in the development of a giant sensitivity fibre refractometer with a sensitivity of around 500 µm/RIU (refractive index unit) and with a magnification factor over 850.