TY - JOUR AU - Greipel, Erika AU - Nagy, Krisztina AU - Csákvári, Eszter AU - Dér, László AU - Galajda, Péter AU - Kutasi, József TI - Chemotactic Interactions of Scenedesmus sp. and Azospirillum brasilense Investigated by Microfluidic Methods JF - MICROBIAL ECOLOGY J2 - MICROB ECOL VL - 87 PY - 2024 IS - 1 SN - 0095-3628 DO - 10.1007/s00248-024-02366-3 UR - https://m2.mtmt.hu/api/publication/34749976 ID - 34749976 N1 - Albitech Biotechnological Ltd, Berlini Út 47-49, Budapest, 1045, Hungary Department of Plant Anatomy, ELTE Eötvös Loránd University, Pázmány Péter Stny 1/C, Budapest, H–1117, Hungary Institute of Biophysics, HUN-REN Biological Research Centre, Szeged, Temesvári Krt. 62, Szeged, 6726, Hungary Division for Biotechnology, Bay Zoltán Nonprofit Ltd. for Applied Research, Derkovits Fasor 2, Szeged, 6726, Hungary Export Date: 3 May 2024 CODEN: MCBEB Correspondence Address: Nagy, K.; Institute of Biophysics, Temesvári Krt. 62, Hungary; email: nagy.krisztina@brc.hu AB - The use of algae for industrial, biotechnological, and agricultural purposes is spreading globally. Scenedesmus species can play an essential role in the food industry and agriculture due to their favorable nutrient content and plant-stimulating properties. Previous research and the development of Scenedesmus -based foliar fertilizers raised several questions about the effectiveness of large-scale algal cultivation and the potential effects of algae on associative rhizobacteria. In the microbiological practice applied in agriculture, bacteria from the genus Azospirillum are one of the most studied plant growth-promoting, associative, nitrogen-fixing bacteria. Co-cultivation with Azospirillum species may be a new way of optimizing Scenedesmus culturing, but the functioning of the co-culture system still needs to be fully understood. It is known that Azospirillum brasilense can produce indole-3-acetic acid, which could stimulate algae growth as a plant hormone. However, the effect of microalgae on Azospirillum bacteria is unclear. In this study, we investigated the behavior of Azospirillum brasilense bacteria in the vicinity of Scenedesmus sp . or its supernatant using a microfluidic device consisting of physically separated but chemically coupled microchambers. Following the spatial distribution of bacteria within the device, we detected a positive chemotactic response toward the microalgae culture. To identify the metabolites responsible for this behavior, we tested the chemoeffector potential of citric acid and oxaloacetic acid, which, according to our HPLC analysis, were present in the algae supernatant in 0.074 mg/ml and 0.116 mg/ml concentrations, respectively. We found that oxaloacetic acid acts as a chemoattractant for Azospirillum brasilense . LA - English DB - MTMT ER - TY - JOUR AU - Wetherington, Miles T. AU - Galajda, Péter AU - Keymer, Juan E. TI - Spatial ecology of cells living in micro-structured environments JF - FRONTIERS IN ECOLOGY AND EVOLUTION J2 - FRONT ECOL EVOL VL - 11 PY - 2023 PG - 4 SN - 2296-701X DO - 10.3389/fevo.2023.1325165 UR - https://m2.mtmt.hu/api/publication/34441845 ID - 34441845 N1 - Funding Agency and Grant Number: James S. McDonnell Foundation Postdoctoral Fellowship; NIH [R35-GM138354]; Hungarian National Research, Development and Innovation Fund [OTKA K 116516, NCN19_170] Funding text: The author(s) declare financial support was received for the research, authorship, and/or publication of this article. MW acknowledges the financial support of the James S. McDonnell Foundation Postdoctoral Fellowship and NIH Grant R35-GM138354. PG acknowledges the support of the Hungarian National Research, Development and Innovation Fund under Grant Number OTKA K 116516. JK acknowledges the financial support from Shenzhen X-Institute and from ANID-Millennium Science Initiative Program-NCN19_170. LA - English DB - MTMT ER - TY - JOUR AU - Wetherington, Miles T AU - Nagy, Krisztina AU - Dér, László AU - Ábrahám, Ágnes AU - Noorlag, Janneke AU - Galajda, Péter AU - Keymer, Juan E. TI - Ecological succession and the competition-colonization trade-off in microbial communities JF - BMC BIOLOGY J2 - BMC BIOL VL - 20 PY - 2022 IS - 1 SN - 1741-7007 DO - 10.1186/s12915-022-01462-5 UR - https://m2.mtmt.hu/api/publication/33288049 ID - 33288049 N1 - Funding Agency and Grant Number: ELKH Biological Research Center; CONICYT FONDECYT [1150430, 1191893]; ANID-Millennium Science Initiative Program [NCN19_170]; JSMF Postdoctoral Fellowship; CONICYT-PFCHA/Doctorado Nacional [2019-21191687]; NKFIH grants [K116516]; ERDF [GINOP-2.3.2-15-2016-00001, -2.3.2-15-201600026, -2.3.2-15-2016-00037]; MTA Janos Bolyai Research Scholarship [BO/00463/18/8]; ITM-UNKP [UNKP-19-4]; NKFIH [PD124889] Funding text: Open access funding provided by ELKH Biological Research Center. JEK, MTW, and JN acknowledge financial support from CONICYT FONDECYT grants 1150430 and 1191893. JEK also thanks ANID-Millennium Science Initiative Program-NCN19_170 for funding. MTW acknowledges support from the JSMF Postdoctoral Fellowship award and CONICYT-PFCHA/Doctorado Nacional/2019-21191687. PG acknowledge support from NKFIH grants K116516 as well as ERDF grants GINOP-2.3.2-15-2016-00001, -2.3.2-15-201600026, and -2.3.2-15-2016-00037. KN thanks the MTA Janos Bolyai Research Scholarship (BO/00463/18/8), ITM-UNKP grant UNKP-19-4 and NKFIH grant PD124889. LA - English DB - MTMT ER - TY - JOUR AU - Bashir, Faiza AU - Kovács, Sándor AU - Ábrahám, Ágnes AU - Nagy, Krisztina AU - Ayaydin, Ferhan AU - Kelemen-Valkony, Ildikó AU - Ferenc, Györgyi AU - Galajda, Péter AU - Tóth, Szilvia Zita AU - Sass, László AU - Kós, Péter AU - Vass, Imre AU - Szabó, Milán TI - Viable protoplast formation of the coral endosymbiont alga Symbiodinium spp. in a microfluidics platform JF - LAB ON A CHIP J2 - LAB CHIP VL - 22 PY - 2022 IS - 16 SP - 2986 EP - 2999 PG - 14 SN - 1473-0197 DO - 10.1039/D2LC00130F UR - https://m2.mtmt.hu/api/publication/32832922 ID - 32832922 N1 - Funding Agency and Grant Number: Hungarian Academy of Sciences, MTA Premium Postdoctoral Research Program [GINOP-2.3.2-15-2016-00026, PREMIUM-2017-38]; National Research, Development and Innovation Office [NKFIH FK 128977, NKFIH K 116016, NKFIH K 116526, NKFIH PD 124889]; Janos Bolyai Research Scholarship of the Hungarian Academy of Sciences [BO/00463/18/8] Funding text: This work was supported by the grants GINOP-2.3.2-15-2016-00026, Hungarian Academy of Sciences, MTA Premium Postdoctoral Research Program PREMIUM-2017-38 (awarded to M. S.), National Research, Development and Innovation Office grant number NKFIH FK 128977 (awarded to M. S.), NKFIH K 116016, NKFIH K 116526 (awarded to P. G.), and NKFIH PD 124889 (awarded to K. N.) K. N. was supported by the Janos Bolyai Research Scholarship of the Hungarian Academy of Sciences (BO/00463/18/8). The authors thank Laszlo Der for valuable discussions and his help with the model calculations. AB - Symbiodiniaceae is an important dinoflagellate family which lives in endosymbiosis with reef invertebrates, including coral polyps, making them central to the holobiont. With coral reefs currently under extreme threat from climate change, there is a pressing need to improve our understanding on the stress tolerance and stress avoidance mechanisms of Symbiodinium spp. Reactive oxygen species (ROS) such as singlet oxygen are central players in mediating various stress responses; however, the detection of ROS using specific dyes is still far from definitive in intact Symbiodinium cells due to the hindrance of uptake of certain fluorescent dyes because of the presence of the cell wall. Protoplast technology provides a promising platform for studying oxidative stress with the main advantage of removed cell wall, however the preparation of viable protoplasts remains a significant challenge. Previous studies have successfully applied cellulose-based protoplast preparation in Symbiodiniaceae; however, the protoplast formation and regeneration process was found to be suboptimal. Here, we present a microfluidics-based platform which allowed protoplast isolation from individually trapped Symbiodinium cells, by using a precisely adjusted flow of cell wall digestion enzymes (cellulase and macerozyme). Trapped single cells exhibited characteristic changes in their morphology, cessation of cell division and a slight decrease in photosynthetic activity during protoplast formation. Following digestion and transfer to regeneration medium, protoplasts remained photosynthetically active, regrew cell walls, regained motility, and entered exponential growth. Elevated flow rates in the microfluidic chambers resulted in somewhat faster protoplast formation; however, cell wall digestion at higher flow rates partially compromised photosynthetic activity. Physiologically competent protoplasts prepared from trapped cells in microfluidic chambers allowed for the first time the visualization of the intracellular localization of singlet oxygen (using Singlet Oxygen Sensor Green dye) in Symbiodiniaceae, potentially opening new avenues for studying oxidative stress. LA - English DB - MTMT ER - TY - JOUR AU - Wetherington, Miles T AU - Nagy, Krisztina AU - Dér, László AU - Noorlag, Janneke AU - Galajda, Péter AU - Keymer, Juan E. TI - Variance in Landscape Connectivity Shifts Microbial Population Scaling JF - FRONTIERS IN MICROBIOLOGY J2 - FRONT MICROBIOL VL - 13 PY - 2022 PG - 7 SN - 1664-302X DO - 10.3389/fmicb.2022.831790 UR - https://m2.mtmt.hu/api/publication/32824517 ID - 32824517 N1 - Export Date: 9 September 2022 AB - Understanding mechanisms shaping distributions and interactions of soil microbes is essential for determining their impact on large scale ecosystem services, such as carbon sequestration, climate regulation, waste decomposition, and nutrient cycling. As the functional unit of soil ecosystems, we focus our attention on the spatial structure of soil macroaggregates. Emulating this complex physico-chemical environment as a patchy habitat landscape we investigate on-chip the effect of changing the connectivity features of this landscape as Escherichia coli forms a metapopulation. We analyze the distributions of E. coli occupancy using Taylor's law, an empirical law in ecology which asserts that the fluctuations in populations is a power law function of the mean. We provide experimental evidence that bacterial metapopulations in patchy habitat landscapes on microchips follow this law. Furthermore, we find that increased variance of patch-corridor connectivity leads to a qualitative transition in the fluctuation scaling. We discuss these results in the context of the spatial ecology of microbes in soil. LA - English DB - MTMT ER - TY - JOUR AU - Nagy, Krisztina AU - Dukic, Barbara AU - Hodula, Orsolya AU - Ábrahám, Ágnes AU - Csákvári, Eszter AU - Dér, László AU - Wetherington, Miles T AU - Noorlag, Janneke AU - Keymer, Juan E. AU - Galajda, Péter TI - Emergence of Resistant Escherichia coli Mutants in Microfluidic On-Chip Antibiotic Gradients JF - FRONTIERS IN MICROBIOLOGY J2 - FRONT MICROBIOL VL - 13 PY - 2022 PG - 12 SN - 1664-302X DO - 10.3389/fmicb.2022.820738 UR - https://m2.mtmt.hu/api/publication/32801357 ID - 32801357 N1 - Funding Agency and Grant Number: Hungarian National Research, Development and Innovation Fund [OTKA PD 124889, K 116516]; New National Excellence Program of the Ministry for Innovation and Technology [UNKP-20-5-SZTE-658]; Janos Bolyai Research Scholarship of the Hungarian Academy of SciencesHungarian Academy of Sciences [BO/00463/18/8]; Hungarian Government; European Regional Development FundEuropean Commission [GINOP-2.3.2-15-2016-00001, GINOP-2.3.2-15-2016-00026, GINOP-2.3.2-15-2016-00037]; James S. McDonnell Foundation Postdoctoral Fellowship award; Chilean National Agency for Science and Innovation (ANID) [CONICYT FONDECYT 1191893]; Millennium Science Initiative Program (ANID Chile) [NCN19_170] Funding text: KN and PG acknowledge the support of the Hungarian National Research, Development and Innovation Fund under Grant Numbers OTKA PD 124889, K 116516, and the UNKP-20-5-SZTE-658 New National Excellence Program of the Ministry for Innovation and Technology. KN was also supported by the Janos Bolyai Research Scholarship of the Hungarian Academy of Sciences (BO/00463/18/8). Furthermore, this work was supported by the Hungarian Government and the European Regional Development Fund under the Grant Numbers GINOP-2.3.2-15-2016-00001, GINOP-2.3.2-15-2016-00026, and GINOP-2.3.2-15-2016-00037. MW gratefully acknowledges support from the James S. McDonnell Foundation Postdoctoral Fellowship award. JK and JN acknowledge funding from the Chilean National Agency for Science and Innovation (ANID), under Grant Number CONICYT FONDECYT 1191893. JK was also supported by the Millennium Science Initiative Program-NCN19_170 (ANID Chile). AB - Spatiotemporal structures and heterogeneities are common in natural habitats, yet their role in the evolution of antibiotic resistance is still to be uncovered. We applied a microfluidic gradient generator device to study the emergence of resistant bacteria in spatial ciprofloxacin gradients. We observed biofilm formation in regions with sub-inhibitory concentrations of antibiotics, which quickly expanded into the high antibiotic regions. In the absence of an explicit structure of the habitat, this multicellular formation led to a spatial structure of the population with local competition and limited migration. Therefore, such structures can function as amplifiers of selection and aid the spread of beneficial mutations. We found that the physical environment itself induces stress-related mutations that later prove beneficial when cells are exposed to antibiotics. This shift in function suggests that exaptation occurs in such experimental scenarios. The above two processes pave the way for the subsequent emergence of highly resistant specific mutations. LA - English DB - MTMT ER - TY - JOUR AU - Széles, Eszter AU - Nagy, Krisztina AU - Ábrahám, Ágnes AU - Kovács, Sándor AU - Podmaniczki, Anna AU - Nagy, Valéria AU - Kovács, László AU - Galajda, Péter AU - Tóth, Szilvia Zita TI - Microfluidic Platforms Designed for Morphological and Photosynthetic Investigations of Chlamydomonas reinhardtii on a Single-Cell Level JF - CELLS J2 - CELLS-BASEL VL - 11 PY - 2022 IS - 2 SN - 2073-4409 DO - 10.3390/cells11020285 UR - https://m2.mtmt.hu/api/publication/32597266 ID - 32597266 N1 - Institute of Plant Biology, Biological Research Centre, Szeged, H-6726, Hungary Doctoral School of Biology, University of Szeged, Szeged, H-6722, Hungary Institute of Biophysics, Biological Research Centre, Szeged, H-6726, Hungary Doctoral School of Multidisciplinary Medical Sciences, University of Szeged, Szeged, H-6720, Hungary Export Date: 12 July 2022 Correspondence Address: Tóth, S.Z.; Institute of Plant Biology, Hungary; email: toth.szilviazita@brc.hu LA - English DB - MTMT ER - TY - JOUR AU - Galajda, Péter AU - Varjú, Katalin TI - Optikai csipesz és nagy energiájú ultragyors lézerimpulzusok: a 2018. évi fizikai Nobel-díjakról JF - MAGYAR TUDOMÁNY J2 - MAGYAR TUDOMÁNY VL - 180 PY - 2019 IS - 6 SP - 904 EP - 911 PG - 8 SN - 0025-0325 DO - 10.1556/2065.180.2019.6.13 UR - https://m2.mtmt.hu/api/publication/31172892 ID - 31172892 LA - Hungarian DB - MTMT ER - TY - JOUR AU - Nagy, Krisztina AU - Ábrahám, Ágnes AU - Keymer, JE AU - Galajda, Péter TI - Application of Microfluidics in Experimental Ecology: The Importance of Being Spatial. JF - FRONTIERS IN MICROBIOLOGY J2 - FRONT MICROBIOL VL - 9 PY - 2018 SN - 1664-302X DO - 10.3389/fmicb.2018.00496 UR - https://m2.mtmt.hu/api/publication/3369018 ID - 3369018 N1 - Biological Research Centre, Institute of Biophysics, Hungarian Academy of Sciences, Szeged, Hungary Doctoral School of Multidisciplinary Medical Science, University of Szeged, Szeged, Hungary School of Biological Sciences and School of Physics, Pontifical Catholic University of Chile, Santiago, Chile Cited By :13 Export Date: 3 May 2021 Correspondence Address: Galajda, P.; Biological Research Centre, Hungary; email: galajda.peter@brc.mta.hu AB - Microfluidics is an emerging technology that is used more and more in biology experiments. Its capabilities of creating precisely controlled conditions in cellular dimensions make it ideal to explore cell-cell and cell-environment interactions. Thus, a wide spectrum of problems in microbial ecology can be studied using engineered microbial habitats. Moreover, artificial microfluidic ecosystems can serve as model systems to test ecology theories and principles that apply on a higher level in the hierarchy of biological organization. In this mini review we aim to demonstrate the versatility of microfluidics and the diversity of its applications that help the advance of microbiology, and in more general, experimental ecology. LA - English DB - MTMT ER - TY - JOUR AU - Nyúl-Tóth, Ádám AU - Kozma, Mihály AU - Nagyőszi, Péter AU - Nagy, Krisztina AU - Fazakas, Csilla AU - Haskó, János AU - Molnár, Kinga AU - Farkas, Elek Attila AU - Végh, Attila Gergely AU - Váró, György AU - Galajda, Péter AU - Wilhelm, Imola Mária AU - Krizbai, István Adorján TI - Expression of pattern recognition receptors and activation of the non-canonical inflammasome pathway in brain pericytes JF - BRAIN BEHAVIOR AND IMMUNITY J2 - BRAIN BEHAV IMMUN VL - 64 PY - 2017 SP - 220 EP - 231 PG - 12 SN - 0889-1591 DO - 10.1016/j.bbi.2017.04.010 UR - https://m2.mtmt.hu/api/publication/3223949 ID - 3223949 AB - Cerebral pericytes are mural cells embedded in the basement membrane of capillaries. Increasing evidence suggests that they play important role in controlling neurovascular functions, i.e. cerebral blood flow, angiogenesis and permeability of the blood-brain barrier. These cells can also influence neuroinflammation which is highly regulated by the innate immune system. Therefore, we systematically tested the pattern recognition receptor expression of brain pericytes. We detected expression of NOD1, NOD2, NLRC5, NLRP1-3, NLRP5, NLRP9, NLRP10 and NLRX mRNA in non-treated cells. Among the ten known human TLRs, TLR2, TLR4, TLR5, TLR6 and TLR10 were found to be expressed. Inflammatory mediators induced the expression of NLRA, NLRC4 and TLR9 and increased the levels of NOD2, TLR2, inflammasome-forming caspases and inflammasome-cleaved interleukins. Oxidative stress, on the other hand, upregulated expression of TLR10 and NLRP9. Activation of selected pattern recognition receptors can lead to inflammasome assembly and caspase-dependent secretion of IL-1beta. TNF-alpha and IFN-gamma increased the levels of pro-IL-1beta and pro-caspase-1 proteins; however, no canonical activation of NLRP1, NLRP2, NLRP3 or NLRC4 inflammasomes could be observed in human brain vascular pericytes. On the other hand, we could demonstrate secretion of active IL-1beta in response to non-canonical inflammasome activation, i.e. intracellular LPS or infection with E. coli bacteria. Our in vitro results indicate that pericytes might have an important regulatory role in neuroinflammation. LA - English DB - MTMT ER -