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Item Open Access Single mutation in iolT1 in ptsG-deficient corynebacterium glutamicum enables growth boost in xylose-containing media(2025) Hofer, Katharina; Schwardmann, Lynn Sophie; Youn, Jung-Won; Wendisch, Volker F.; Takors, RalfEfficient co-utilization of glucose and xylose from lignocellulosic biomass remains a critical bottleneck limiting the viability of sustainable biorefineries. While Corynebacterium glutamicum has emerged as a promising industrial host due to its robustness, further improvements in mixed-sugar co-utilization are needed. Here, we demonstrate how a single amino acid substitution can dramatically transform cellular sugar transport capacity. By combining rational strain engineering with continuous adaptive laboratory evolution, we evolved a ptsG -deficient C. glutamicum strain in glucose-xylose mixtures for 600 h under consistent selection pressure. Whole-genome sequencing revealed a remarkable finding: a single point mutation; exchanging proline for alanine in the myo -inositol/proton symporter IolT1 was sufficient to boost glucose uptake by 83% and xylose uptake by 20%, while increasing the overall growth rate by 35%. This mutation, located in a highly conserved domain, likely disrupts an alpha helical structure, thus enhancing transport function. Reverse engineering confirmed that this single change alone reproduces the evolved phenotype, representing the first report of an engineered IolT1 variant in PTS-independent C. glutamicum that features significantly enhanced substrate uptake. These results both provide an immediately applicable engineering target for biorefinery applications and demonstrate the power of evolutionary approaches to identify non-intuitive solutions to complex metabolic engineering challenges.Item Open Access Sudden elevation of carbon dioxide concentration causes perturbation of the electron transport chain and triggers defense responses in Arabidopsis thaliana(2026) Shokouhi, Danial; Hernandez, Jakob Sebastian; Walther, Dirk; Kepp, Gabriele; Schwenkert, Serena; Leister, Dario; Gremmels, Jürgen; Zuther, Ellen; Alpers, Jessica; Nägele, Thomas; Heyer, Arnd G.Main conclusionArabidopsis wildtype plants suffer symptoms of stress at a sudden increase in CO2 concentration, resulting from perturbation of photosynthetic electron transport. Defense-related gene induction includes increased methionine cycle and glucosinolates metabolism.AbstractElevated CO2 (eCO2) increases photosynthetic performance of plants, but also leads to decreased nitrogen-to-carbon ratio and a long-term decline in photosynthetic activity, known as photosynthetic acclimation. It is unclear whether initially increased CO2 assimilation or perturbation of the physiological homeostasis triggers acclimation. Here, we used a combination of omics analysis to investigate immediate (1 day) and delayed (7 days) responses of plants to rising atmospheric CO2, thus allowing us to discriminate regulatory from metabolic effects. Responses of wildtype Arabidopsis plants, Columbia-0, were compared to those of the hpr1-1 mutant of peroxisomal hydroxy-pyruvate reductase that has reduced photorespiratory turnover at ambient CO2. Comparisons enabled separating the impact of eCO2 (1000 ppm) on increased carbon assimilation from that of reduced photorespiration. While both genotypes had elevated sugar levels at eCO2, the wildtype displayed symptoms of stress that were accompanied by perturbation of the photosynthetic electron transport chain. These were consistent with physiological parameters, including non-photochemical quenching and chlorophyll fluorescence. The induction of defense-related mechanisms was tightly associated with increased sulfate assimilation, methionine cycle activity and glucosinolates metabolism, all being early responses of the wildtype to eCO2. Transcriptome data pointed to hexokinase1 as a central regulatory hub in orchestrating these responses. In contrast, eCO2 enabled the hpr1-1 mutant to metabolically align with the wildtype. Results offer new interpretations of how the impairment of carbon and nitrogen recycling is compensated in the hpr1-1 mutant.Item Open Access Health and liver diagnostic markers influencing glycemia in subjects with prediabetes : Preview study(2024) Ramos-Lopez, Omar; Martinez-Urbistondo, Diego; Navas-Carretero, Santiago; Zhu, Ruixin; Huttunen-Lenz, Maija; Stratton, Gareth; Handjieva-Darlenska, Teodora; Handjiev, Svetoslav; Sundvall, Jouko Ensio; Silvestre, Marta P.; Jalo, Elli; Pietiläinen, Kirsi H.; Adam, Tanja C.; Westerterp-Plantenga, Margriet; Simpson, Elizabeth; MacDonald, Ian; Taylor, Moira A.; Poppitt, Sally D.; Schlicht, Wolfgang; Brand-Miller, Jennie; Fogelholm, Mikael; Raben, Anne; Martinez, J. AlfredoIntroduction: Glucose homeostasis may be dependent on liver conditions and influence health-related markers and quality of life (QoL) objective measurements. This study aimed to analyze the interactions of glycemia with liver and health status in a prediabetic population. Subjects and methods: This study included 2220 overweight/obese prediabetics from the multinational PREVIEW project. Anthropometrics; clinical, metabolic and other health-related markers; and QoL variables were analyzed. Univariate and multilinear-adjusted regression models were run to explain the interrelationships and effect modification between glycemia, health-related QoL (applying SF-12) and metabolic/liver health (using the HSI, a putative marker of fatty liver). Results: Relevant age/sex interactions were found concerning the levels of insulin, HOMA-IR, C peptide and transaminases in this prediabetic population. Multivariate models identified age, sex, glucose, WC and QoL as important predictors of HSI variability (adj. R value = 0.1393, p < 0.001), whereas the QoL status was statistically related to age, sex, HOMA-IR and HSI (adj. R value = 0.1130, p < 0.001) in this glycemia-impaired group. Furthermore, the QoL values declined with increased HSI scores, where a significant interaction was found ( p = 0.011) when the data were analyzed when comparing lower glycemia vs. higher glycemia in prediabetics. Indeed, an effect modification was featured depending on the glycemia levels concerning the QoL and HSI worsening. Conclusion: Glycemia associations with the QoL status and liver metabolism markers were evidenced, with clinical implications for diabetes and liver disease precision management given the modification of the QoL outcomes depending on the liver status and glycemia concentrations. Notably, independent associations of circulating glucose with age, sex, adiposity, inflammation and C peptide levels were found.Item Open Access Tunable, permanent and instantly available super-wettability states on metal surfaces by laser texturing and plasma coating(2025) Holder, Daniel; Reichle, Paul; Umlauf, Georg; Weber, Rudolf; Barz, Jakob; Graf, ThomasWettability, the ability of a liquid to spread on or repel from a surface, holds particular significance for applications requiring extreme control of liquid interaction, including self-cleaning, anti-icing, dropwise condensation, anti-fogging, and enhanced fluid transport. This work investigates the synergistic combination of laser surface texturing and plasma-enhanced chemical vapor deposition (PECVD) to achieve tunable, permanent, and instantly available super-wettability states on metal surfaces. Ultrashort laser pulses were employed to produce various surface textures, ranging from fine nanoscale ripples to rougher microtextures such as microgrooves, spikes, and holes, on stainless steel AISI 304, copper, and the titanium alloy Ti64. PECVD coatings, including thin layers of glass and polymers, were subsequently applied to these textures to modulate surface chemistry and achieve the desired wettability.The results demonstrate that superhydrophilic surfaces with a water contact angle θ < 10° were achieved by combining rough textures with thin glass coatings, offering long-term stability that could be simply renewed via ultrasonic cleaning. Conversely, superhydrophobic surfaces with a water contact angle θ > 150° were instantly obtained using polymer coatings on rough textures. These functionalized surfaces also exhibited exceptional liquid repellence for complex liquids, such as milk and beer, making them particularly suitable for special applications using solutions or emulsions. The integration of laser texturing and PECVD coating provides a versatile and simple pathway for fabricating functional surfaces with tunable wettability and long-term performance across multiple metals and fluids.Item Open Access Mechanical properties of architected polymer lattice materials : a comparative study of additive manufacturing and CAD using FEM and µ‐CT(2025) Walker, Oliver; Roland, Thierry; Favier, Damien; Egele, Antoine; Heymann, Michael; Stubenrauch, CosimaMechanical properties of porous lattice materials can be tuned by the structure. Thus, the effect of the unit cell design on the mechanical properties is of special interest. However, studies often lack an in‐depth investigation of the underlying mechanisms. Additionally, inhomogeneous bulk material properties and structural deviations introduced during manufacturing are often neglected. Here, the impact of the pore shape on Young's modulus, initial peak stress, and energy absorbance of lattice materials is investigated. Structural deviations of 3D‐printed lattice materials from the computer‐aided design (CAD) are examined, and analyze how they affect the mechanical properties. For comparability, the porosity, overall dimensions, and unit cell size of the lattice material are kept constant. Flexible lattice materials assembled of 3 × 3 × 3 unit cells are 3D‐printed (stereolithography). Mechanical properties are determined through uniaxial compression tests and finite element modeling (FEM). Deviations between CAD and 3D‐printed lattice materials are analyzed using micro‐computed tomography (µ‐CT). Combining µ‐CT with FEM revealed the impact of these deviations on the mechanical properties. It is found that the mechanical properties depend indeed on the pore shape. Furthermore, a pyramidal shape along the printing direction and displaced or deformed pores are observed in the 3D‐printed lattice materials, all of which result in reduced mechanical properties.Item Open Access Motile and chemotactic minicells and minicell-driven biohybrids engineered for active cargo delivery(2025) Kalita, Irina; Colin, Remy; Hoch, Sarah; Baltaci, Saadet Fatma; Sitti, Metin; Sourjik, VictorBacterial minicells are submicrometer-sized spherical compartments produced by bacteria as a result of aberrant cell division. Minicells have a similar cellular composition to the parental bacteria but lack chromosomal DNA and are thus unable to proliferate. Due to that, minicells have attracted attention as potential means of effector delivery in bioengineering and biomedical applications. However, until now, the efficiency of delivery by minicells has been limited by passive collisions with their targets. To develop minicell-based active delivery, here we engineer Escherichia coli strains generating motile minicells with enhanced swimming properties by introducing genetic modifications specifically targeting flagella number, length, and rotation speed. The engineered minicells preserve motility over an extended period of time and, in contrast to parental E. coli cells, increase their swimming speed for the intermediate viscosity of the medium. Despite their small size, minicells show an efficient chemotactic response and utilize the same chemotactic strategy as parental E. coli cells. Moreover, we develop a procedure for conjugating minicells with cargo particles and demonstrate that such minicell-driven biohybrid swimmers are chemotactic and thus capable of actively accumulating at the source of an attractant. These engineered chemotactic minicells and minicell-based biohybrids can serve as cargo delivery platforms with active targeting, thus overcoming the challenges posed by nontargeted therapies.Item Open Access Optimization of the parameters of a minimal coagulation model(2025) Link, Carolin; Janiga, Gábor; Thévenin, DominiqueThe formation of a blood clot within a vessel can result in its complete blockage. This phenomenon, known as thrombosis, can have severe consequences. In contrary, thrombosis can be sometimes desirable. Intra-aneurysmal thrombosis is the primary objective of an endovascular treatment aimed at occluding the aneurysm sac. The proper modeling of the coagulation system is, therefore, important for the prediction, early recognition, and prevention of these tendencies. In silico investigations based on computational fluid dynamics (CFD) extended by thrombosis models provide a valuable tool for a detailed analysis. Minimal models are particularly useful for practical purposes to reduce computational efforts. This work proposes an approach to adapt the parameters of a minimal model to reproduce the behavior obtained with a comprehensive description of the coagulation cascade. The objective is to obtain the same thrombin generation curves while reducing strongly computational costs. For this purpose, machine learning—based here on an evolutionary algorithm—is used to optimize the obtained agreement. By adapting the reaction rate coefficients, a significant improvement can be achieved. The obtained results pave the way for future applications of the improved model in complex configurations such as for planning personalized interventions. Notably, the minimal model will be used for CFD in future studies to take advantage of its low computational cost.Item Open Access The kinase NEK6 positively regulates LSD1 activity and accumulation in local chromatin sub-compartments(2024) Knodel, Franziska; Eirich, Jürgen; Pinter, Sabine; Eisler, Stephan A.; Finkemeier, Iris; Rathert, PhilippLSD1 plays a crucial role in mammalian biology, regulated through interactions with coregulators and post-translational modifications. Here we show that the kinase NEK6 stimulates LSD1 activity in cells and observe a strong colocalization of NEK6 and LSD1 at distinct chromatin sub-compartments (CSCs). We demonstrate that LSD1 is a substrate for NEK6 phosphorylation at the N-terminal intrinsically disordered region (IDR) of LSD1, which shows phase separation behavior in vitro and in cells. The LSD1-IDR is important for LSD1 activity and functions to co-compartmentalize NEK6, histone peptides and DNA. The subsequent phosphorylation of LSD1 by NEK6 supports the concentration of LSD1 at these distinct CSCs, which is imperative for dynamic control of transcription. This suggest that phase separation is crucial for the regulatory function of LSD1 and our findings highlight the role of NEK6 in modulating LSD1 activity and phase separation, expanding our understanding of LSD1 regulation and its implications in cellular processes.Item Open Access Targeting glioblastoma mitochondrial metabolism with S-Gboxin induces cytotoxicity under conditions of the tumor microenvironment(2026) Weinem, Jan-Béla; Urban, Hans; Sauer, Benedikt; Buhlmann, Tanja; Hau, Ann-Christin; Liebner, Stefan; Rusch, Tillmann; Namgaladze, Dmitry; Harwart, Leander F.; Schröder, Jan-Hendrik; de Souza, Maeve; Steinbach, Joachim P.; Legewie, Stefan; Luger, Anna-Luisa; Ronellenfitsch, Michael W.Glioblastoma (GB) is the most common primary malignant brain tumor in adults. Gboxin, a novel compound that targets oxidative phosphorylation via complex V inhibition, has shown promise in preclinical models of GB. We examined the efficacy of the pharmacokinetically optimized S-Gboxin under conditions replicating the GB microenvironment, including nutrient deprivation and hypoxia. We assessed cytotoxicity and growth-inhibitory effects of S-Gboxin in human GB cell lines, primary GB cultures, as well as immortalized and primary human astrocytes under different nutrient and oxygen deprivation scenarios. Oxygen consumption, cell migration, activation of the integrated stress response (ISR) as well as the relevance of the AMP-activated protein kinase (AMPK) were evaluated as variables under S-Gboxin treatment. S-Gboxin demonstrated cytotoxicity at low micromolar concentrations, with cell death enhanced under nutrient deprivation and hypoxia. S-Gboxin reduced cellular oxygen consumption and uncoupled mitochondria. Cytotoxicity was increased when mitochondrial fuels were the primary energy source. Additionally, S-Gboxin treatment resulted in elevated lactate production and glucose consumption. While the ISR marker ATF4 was induced by S-Gboxin in a dose-dependent manner, ISR inhibition with ISRIB did not affect its cytotoxicity. Conversely, S-Gboxin treatment combined with AMPK inhibition resulted in enhanced tumor cell death. Collectively, these findings demonstrate that S-Gboxin selectively targets cancer-specific metabolic vulnerabilities in GB cells. The synergistic action with AMPK inhibition suggests that this pathway contributes to maintain energy homeostasis in the presence of the drug. Therefore, S-Gboxin is a promising compound for GB therapy, especially in a combinatory approach with AMPK inhibition or other metabolic targeted therapies.Item Open Access Effects of blood flow restriction on motoneurons synchronization(2025) Taleshi, Mansour; Bubeck, Franziska; Gizzi, Leonardo; Vujaklija, IvanBlood flow restriction (BFR) is a peripheral intervention that induces transient and reversible physiological perturbations. While this intervention offers a unique model to explore neuromuscular responses in multiple contexts, its impact on neural input to motoneurons remains unclear. Here, the influence of BFR on muscle force control, behavior, and neural input to motoneurons during isometric-trapezoidal and isometric-sinusoidal little finger abduction precision tasks has been studied. Sixteen healthy participants performed the tasks under pre-BFR, during BFR, and at two post-BFR conditions. High-density surface electromyography (EMG) was recorded from the abductor digiti minimi muscle, and motor unit spike trains (MUST) were decomposed using blind source separation technique. Coherence between cumulative spike trains (CSTs) of identified motor units was calculated to assess common synaptic input in the delta and alpha frequency bands. As expected, during BFR application, participants reported higher level of discomfort and significant deterioration in force-tracking performance, as measured using root mean square error (RMSE). Following the BFR release, the level of discomfort, along with impaired neuromuscular performance were reduced to pre-BFR condition. Coherence analysis revealed a prominent peak in the alpha band. The mean z-score coherence in the alpha band showed a reduction of 27% for isometric-trapezoidal and 31% for isometric-sinusoidal conditions from pre-BFR to BFR, followed by a rebound post-BFR intervention with increases of 13% and 20%, respectively. In the delta band, coherence values were consistently higher during sinusoidal tasks compared to trapezoidal ones. These findings indicate that brief BFR application led to decrease in motoneuron synchronization and force control precision likely due to desensitization as shown by changes in coherence alpha band.