Microbial Cell Factories最新文献

{"title":"Employing Streptomyces enissocaesilis as a sustainable cell factory for green synthesis of gold nanoparticles with multi-target anticancer activity against MCF-7 breast cancer cells.","authors":"Maisra M El-Bouseary, Sara Ahmed Mohammed Mahmoud Badr, Fatma Sonbol, Tarek El-Banna, Amr Tayel, Mohamed M El-Zahed, Engy Elekhnawy","doi":"10.1186/s12934-026-03113-8","DOIUrl":"10.1186/s12934-026-03113-8","url":null,"abstract":"<p><strong>Background: </strong>Currently, there is growing interest in gold nanoparticles (AuNPs) to be employed in cancer nanomedicine. This study describes the green synthesis of AuNPs using an actinobacterial isolate identified as Streptomyces enissocaesilis via 16 S rRNA sequencing. Characterization of the nanoparticles was performed using various techniques including UV-Vis spectroscopy, FTIR, TEM, XRD, EDX, and zeta-potential analysis. To provide insight into the interaction of AuNPs with MCF-7 breast cancer cells, a variety of apoptosis and cell proliferation assays were performed. These assays included concentration-dependent cytotoxicity testing, cell-cycle analysis, an Annexin V-FITC/PI apoptosis analysis, AO/PI staining, a BrdU proliferation assay, and an RT-qPCR to evaluate the expression of c-erbB-2 and p53.</p><p><strong>Results: </strong>Characterization of the AuNPs revealed that they were ruby-red, exhibited a strong SPR signal at 528 nm, were between 22.73 and 35.61 nm in size, had a positive zeta potential at + 27 mV, and exhibited a faceted crystal cubic structure. In regard to MCF-7 cells, the concentration-dependent cytotoxicity assay showed a clear dose-dependent inhibition of cell proliferation, with growth inhibition increasing from 20.14% at 3.125 µg/mL to 98.33% at 100 µg/mL and a half-maximal inhibitory concentration (IC₅₀) of 8.32 µg/mL, considerably lower than the 18.90 µg/mL obtained for normal PBMC cells under the same protocol. Cell cycle analysis showed that AuNPs caused almost complete cell cycle arrest in the G0/G1 phase (99.25%) of the cell cycle, while both the G2/M and S phases were completely depleted. BrdU incorporation was significantly inhibited in a concentration-dependent manner. Finally, RT-qPCR and Annexin V-FITC/PI apoptosis analysis showed that AuNPs induced apoptosis (50.36%) and significantly inhibited the expression of the oncogene c-erbB-2, and in turn, they induced tumor suppressive pathway. The docking studies revealed that the Cys-Au species bound to biologically significant areas of ERα and CDK2, possibly explaining the antiproliferative effects observed in MCF-7 human breast cancer cells.</p><p><strong>Conclusions: </strong>These findings indicate that AuNPs biosynthesized using Streptomyces enissocaesilis exhibit significant anticancer effects against MCF-7 cells. The effects appear to be induced by a combination of antiproliferative, pro-apoptotic, and cell-cycle- and gene-modulatory effects. These effects validate the promise of Actinobacteria-stabilized AuNPs as a green nanoplatform for the treatment of human breast cancer.</p>","PeriodicalId":18582,"journal":{"name":"Microbial Cell Factories","volume":"25 1","pages":""},"PeriodicalIF":5.8,"publicationDate":"2026-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13625260/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149081353","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Microbial production of eumelanin from a desert-derived Aspergillus terreus: statistical optimization, comprehensive characterization, and in silico insights into breast cancer-associated targets.","authors":"Shimaa El-Sapagh, El-Refaie Kenawy, Sara Ahmed, Ebrahim M Shalamesh, Nessma A El-Zawawy","doi":"10.1186/s12934-026-03114-7","DOIUrl":"10.1186/s12934-026-03114-7","url":null,"abstract":"&lt;p&gt;&lt;strong&gt;Background: &lt;/strong&gt;Naturally derived microbial products are increasingly explored as sustainable sources of bioactive compounds for targeted cancer applications. Among these, eumelanin is a nitrogen-containing polymeric pigment produced by various microorganisms, including fungi, and is distinguished by its unique physicochemical properties, biocompatibility, and free radical scavenging capacity. Nevertheless, eumelanin-producing fungi from extreme desert habitats remain poorly explored, particularly those isolated from the Wadi Allaqi Biosphere Reserve, and comprehensive studies integrating production optimization, structural characterization, and breast cancer-focused cytotoxic evaluation are still limited.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Results: &lt;/strong&gt;In this work, melanin was isolated from a rhizosphere soil-derived fungal isolate obtained from the Wadi Allaqi Biosphere Reserve and identified as Aspergillus terreus AUMC15773 through morphological examination and molecular characterization with accession number OP941720. To the best of our knowledge, this is the first report describing a melanin-producing A. terreus isolated from the Wadi Allaqi Biosphere Reserve, followed by comprehensive optimization, structural characterization, and breast cancer-focused cytotoxic evaluation. Melanin extraction was achieved using acid precipitation, followed by statistical optimization of culture parameters employing Plackett-Burman design and response surface methodology. This approach led to a marked increase in melanin yield, reaching 102.9 mg/10 mL compared to the initial production of 20.19 mg/10 mL indicating a 5.1 fold increase. Chromatographic analysis using thin-layer chromatography indicated a single band (Rf = 0.7), suggesting purified melanin. Structural and chemical features were confirmed using UV-visible spectroscopy, FTIR, Raman spectroscopy, and NMR, identifying the compound as DOPA-type eumelanin. Elemental profiling further supported this classification, showing a nitrogen-rich composition with low sulfur content. DPPH free radical scavenging activity assay indicated that extracted eu-melanin had antioxidant activity similar to ascorbic acid. The cytotoxic activity of the extracted eumelanin was evaluated using MCF-7 breast cancer cells and normal WI-38 fibroblasts. The purified pigment reduced the viability of MCF-7 cells while exhibiting minimal cytotoxicity toward WI-38 cells, indicating favorable biocompatibility. In silico, molecular docking revealed a stronger interaction with estrogen receptor alpha (ERα) (binding energy - 8.0 kcal/mol) compared to breast cancer susceptibility protein BRCA1 (- 6.6 kcal/mol), providing supportive computational evidence that complements the in vitro findings involving ERα modulation.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Conclusion: &lt;/strong&gt;This study establishes a desert-derived A. terreus isolate as a promising microbial cell factory for eumelanin production through statistical optimization and comprehensive structural ch","PeriodicalId":18582,"journal":{"name":"Microbial Cell Factories","volume":"25 1","pages":""},"PeriodicalIF":5.8,"publicationDate":"2026-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13615586/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149062367","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Retraction Note: Production, bioprocessing and antiproliferative activity of camptothecin from Aspergillus terreus, endophyte of Cinnamomum camphora: restoring their biosynthesis by indigenous microbiome of C. camphora.","authors":"Abeer Eldeghidy, Gamal Abdel-Fattah, Ashraf S A El-Sayed, Ghada G Abdel-Fattah","doi":"10.1186/s12934-026-03130-7","DOIUrl":"10.1186/s12934-026-03130-7","url":null,"abstract":"","PeriodicalId":18582,"journal":{"name":"Microbial Cell Factories","volume":"25 1","pages":""},"PeriodicalIF":5.8,"publicationDate":"2026-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13599329/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149030953","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Coupling bacterial nitrogen fixation to yeast whole-cell biocatalysis enables amine production using air as the sole nitrogen source.","authors":"Khaled Youssef, Ed W J van Niel, Brett Barney, Magnus Carlquist","doi":"10.1186/s12934-026-03118-3","DOIUrl":"10.1186/s12934-026-03118-3","url":null,"abstract":"<p><strong>Background: </strong>Alkylamine production depends on ammonium produced via the energy-intensive, fossil-based Haber-Bosch process. Diazotrophic bacteria could offer a biological alternative by supplying nitrogen directly from air to heterotrophic whole-cell biocatalysts for alkylamine production. However, their integration with yeast production systems remains largely unexplored.</p><p><strong>Results: </strong>Here, we evaluated the use of an ammonium-excreting strain of Azotobacter vinelandii (AZBB664) to supply nitrogen to an engineered Saccharomyces cerevisiae biocatalyst for vanillylamine production using air as the sole nitrogen source. A modified Burk's medium was developed to support S. cerevisiae growth and enable evaluation of biologically supplied nitrogen. Co-cultivation of both organisms was feasible under diazotrophic conditions, however, vanillin oxidation by A. vinelandii prevented effective vanillylamine production. To address this, a sequential process was implemented in which A. vinelandii was first used to generate ammonium in a modified Burk's medium, followed by cell removal and use of the resulting medium (AZM1) for yeast cultivation. In this medium, the yeast strain CEN.PK 113-7d exhibited a growth rate of 0.27 h^- 1 and reached higher final cell density compared to the control medium supplemented with synthetic ammonium. Cultivation in AZM1 was associated with a more stable pH profile, which may have contributed to the improved growth of the yeast. S. cerevisiae strain TMBNM033 expressing recombinant transaminase and alanine dehydrogenase was able to convert vanillin to vanillylamine, although a significant amount of vanillic alcohol was also observed due to competing endogenous reductase activity.</p><p><strong>Conclusions: </strong>A. vinelandii-derived medium enables yeast growth and whole-cell reductive amination using air as the sole nitrogen source. This demonstrates that biologically fixed nitrogen can directly sustain heterotrophic whole-cell biotransformations, establishing a strategy for coupling diazotrophy with biocatalytic production systems.</p>","PeriodicalId":18582,"journal":{"name":"Microbial Cell Factories","volume":"25 1","pages":""},"PeriodicalIF":5.8,"publicationDate":"2026-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13584442/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148983183","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"TEM analysis of iron nanoparticle-loaded endophytic bacteria mitigating salinity-induced root stress effects in maize.","authors":"Amany M Reyad, Yasmeen M Fathy, Aya M Rabie, Tharwat E E Radwan, Karima Ali Sayed","doi":"10.1186/s12934-026-03106-7","DOIUrl":"10.1186/s12934-026-03106-7","url":null,"abstract":"<p><p>Salinity stress is a major abiotic constraint limiting crop productivity through osmotic imbalance, ionic toxicity, oxidative damage, and structural disruption. Here, we report a novel nano-enabled microbial cell factory system based on iron nanoparticle (FeNP)-loaded plant growth-promoting endophytic bacteria (PGPEB) isolated from Zea mays roots and identified as Bacillus sp. (16S rRNA accession MZ700077.1; 99.41% similarity). This living nano-bio hybrid was designed to integrate microbial plant growth-promoting functions with nanoparticle-mediated micronutrient delivery for enhanced salinity stress tolerance. Transmission electron microscopy confirmed successful formation of the microbial cell factory, revealing rod-shaped bacterial cells with intact flagella and uniform spherical FeNPs (~ 29.9 nm) strongly associated with the bacterial surface, indicating stable nano-bio interfacing without compromising cellular integrity. The engineered FeNP-PGPEB system significantly improved maize seed germination, root and shoot growth, and overall seedling vigor under moderate to severe salinity (200 mM NaCl), outperforming either PGPEB or FeNPs alone and demonstrating clear synergistic effects. Physiological and biochemical analyses revealed that the nano-bio formulation enhanced antioxidant defense systems (SOD, CAT, POD), increased proline accumulation, and optimized phytohormonal balance by elevating IAA and moderating ABA levels. In addition, lipid peroxidation (MDA) was reduced, while relative water content was maintained, indicating improved redox homeostasis and osmotic regulation. Ultrastructural and anatomical observations further confirmed reduced plasmolysis, improved membrane integrity, and enhanced vascular and root tissue organization under salt stress. Multivariate analyses (PCA and clustering) clearly distinguished treatments, with FeNP-PGPEB strongly associated with stress resilience traits and improved physiological stability. Overall, this study establishes a novel microbial cell factory platform, where endophytic Bacillus acts as a living nanocarrier for iron delivery, integrating microbial biotechnology and nanotechnology into a unified strategy for enhancing crop tolerance to salinity stress and advancing sustainable agricultural systems.</p>","PeriodicalId":18582,"journal":{"name":"Microbial Cell Factories","volume":"25 1","pages":""},"PeriodicalIF":5.8,"publicationDate":"2026-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13545777/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148897587","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characterisation of metabolic burden in Pseudomonas putida reveals precursor limitation in heterologous lycopene production.","authors":"Carina Meiners, Lucas Hermann, Mishela Stoja, Andreas Kremling, Katharina Pflüger-Grau","doi":"10.1186/s12934-026-03108-5","DOIUrl":"10.1186/s12934-026-03108-5","url":null,"abstract":"<p><strong>Background: </strong>The introduction of heterologous pathways into microbial hosts often imposes a metabolic burden on the cell, arising from three major physiological constraint layers: competition for gene expression resources, limited precursor availability and flux distribution, and insufficient energy and redox supply. Although Pseudomonas putida KT2440 is considered a robust and metabolically versatile production host, it remains unclear which of these constraint layers primarily limits heterologous terpenoid production in this organism. Here, lycopene biosynthesis was used as a model system to systematically dissect these three potential sources of metabolic burden.</p><p><strong>Results: </strong>A capacity-monitoring system revealed no clear reduction in transcriptional or translational capacity across the tested strains and cultivation conditions, indicating that general gene expression capacity was not the primary limiting factor. Instead, lycopene production depended strongly on promoter architecture and plasmid backbone, showing that regulatory design shaped pathway performance. Enhancing precursor supply by introducing a heterologous mevalonate (MVA) pathway substantially increased product titres, identifying precursor availability from the native MEP pathway as the dominant bottleneck. This conclusion was independently supported by exogenous mevalonate supplementation, which further increased lycopene accumulation but also revealed saturation at higher concentrations, suggesting that downstream pathway balance or enzyme capacity became limiting once precursor supply was relieved. Under controlled bioreactor conditions, lycopene titres increased from approximately 1 mg/L to nearly 25 mg/L, indicating that process conditions further modulate production performance, suggesting an additional contribution of process-dependent energy and redox constraints.</p><p><strong>Conclusion: </strong>Metabolic burden during heterologous lycopene production in P. putida is governed primarily by precursor availability rather than by limitations in general gene expression capacity. Regulatory properties of the vector system strongly influence pathway performance, while controlled cultivation conditions can further improve production by alleviating additional process-dependent constraints. Together, these findings provide a systematic framework for distinguishing constraint layers and guiding the optimisation of heterologous terpenoid production systems.</p>","PeriodicalId":18582,"journal":{"name":"Microbial Cell Factories","volume":"25 1","pages":""},"PeriodicalIF":5.8,"publicationDate":"2026-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13540941/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148880932","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Recombinant thermotolerant alkaline lipase from Lysinibacillus fusiformis for detergent and hard (Ras) cheese applications: cloning, expression, molecular docking, and characterization.","authors":"Ghada M El-Sayed, Hala R Wehaidy, Adel M M Kholif, Walaa H Salama, Rasha G Salim","doi":"10.1186/s12934-026-03084-w","DOIUrl":"10.1186/s12934-026-03084-w","url":null,"abstract":"<p><strong>Background: </strong>Thermostable and alkaline lipases are of significant interest for industrial applications, particularly in detergents and food processing. This study aimed to isolate, clone, and express lipase-encoding genes from a potent bacterial source to produce a thermo-tolerant alkaline lipase with enhanced catalytic efficiency and practical applicability.</p><p><strong>Results: </strong>Among several bacterial isolates, the most potent lipase producer was identified as Lysinibacillus fusiformis, and its 16 S rRNA sequence was deposited in GenBank (PP757498). Three lipase-encoding genes (est, est2, and lipA) were successfully isolated, cloned, and heterologously expressed in Escherichia coli BL21 (DE3). Their sequences were submitted to GenBank under accession numbers PX136937.1, PX136938.1, and PX136936.1, respectively. The recombinant lipase encoded by lipA (rLipase) exhibited the highest activity (150 U/mL) compared with the native enzyme (56.2 U/mL). Molecular docking analysis demonstrated strong binding affinity of rLipase toward major fatty acid derivatives in olive oil, with the highest affinity for linoleic acid (- 8.0 kcal/mol), followed by oleic acid (- 7.8 kcal/mol) and palmitic acid (- 7.3 kcal/mol). These interactions were stabilized by hydrophobic interactions and hydrogen bonding, with key contributions from critical amino acid residues, particularly VAL250. The partially purified recombinant lipase (rLipase) exhibited a maximum activity of 320 U/mL at 80 °C and pH 9, demonstrating remarkable thermostability and alkaline tolerance. Functional evaluation showed that rLipase improved the detergent efficiency for oil stain-removal from cotton fabrics. In addition, supplementation with 0.4% rLipase accelerated Ras cheese ripening by shortening the maturation period from 120 to 90 days with maintaining the desired ripening process.</p><p><strong>Conclusions: </strong>The recombinant lipase from Lysinibacillus fusiformis demonstrated high thermal stability, alkaline tolerance, and strong catalytic efficiency. Its effectiveness in detergent formulations and cheese ripening highlights its potential as a versatile industrial biocatalyst for lipid bioconversion and related applications.</p>","PeriodicalId":18582,"journal":{"name":"Microbial Cell Factories","volume":"25 1","pages":""},"PeriodicalIF":5.8,"publicationDate":"2026-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13526305/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148857556","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"High-cell-density Escherichia coli-based nanobody production: benchmarking of subcellular targeting, strain background and process development strategies.","authors":"Jan-Angelus Meyer, Marie Beneke, Sadija Altmüller, Alexander Reeb, Jannis Künzl, Nathalie Opilo, Theo Weise, Christos Gouloudis, Rebekka Biedendieck, Rainer Krull","doi":"10.1186/s12934-026-03093-9","DOIUrl":"10.1186/s12934-026-03093-9","url":null,"abstract":"<p><strong>Background: </strong>Nanobodies (NB) are compact single-domain antibody fragments with substantial diagnostic and therapeutic potential, but scalable microbial production under controlled bioreactor conditions remains insufficiently characterized. In this study a high-cell-density cultivation (HCDC) fed-batch process for an anti-human CD45 NB in Escherichia coli was established and evaluated how process parameters, host background, and subcellular targeting (cytoplasmic vs. periplasmic) affect yield and product quality including correct disulfide bond formation.</p><p><strong>Results: </strong>Using a two-stage design-of-experiments (DoE) strategy in 2 L stirred-tank bioreactors, OD_600nm at induction and post-induction temperature were identified as the main process variables controlling the post-purification nanobody concentration, whereas inducer concentration had no relevant effect within the tested range. Late induction at OD_600nm 125-150 combined with production temperatures around 21-22.5 °C defined a robust operating window and yielded more than 2.5 g L^-1 purified nanobody after Strep-tag affinity chromatography. Benchmarking of five host strain-plasmid combinations under standardized HCDC conditions further increased NB yield indicating that production performance was directly governed by the combined host background and expression architecture. While E. coli NEBExpress® with periplasmic SP_PelB targeting reached around 2.4 g L^-1 anti-hCD45 NB and the highest volumetric productivity (0.122 g L^-1 h^-1), E. coli SHuffle® T7 Express produced 2.2 g L^-1 anti-hCD45 NB intracellularly. Nanobody-quality analysis revealed a pronounced difference between production routes. NB preparations obtained from periplasmic targeting constructs formed thermally uniform species with single nano differential scanning fluorimetry (DSF) unfolding transitions at 73.27-74.05 °C, whereas cytoplasmic derived preparations showed biphasic unfolding profiles with lower first transitions at 51.62-55.31 °C and second transitions at 68.30-71.53 °C indicating a higher thermal stability and also folding uniformity for secreted anti-hCD45 NB. Finally, flow cytometry confirmed functional binding of all tested anti-hCD45 NB to CD45-positive Jurkat cells.</p><p><strong>Conclusions: </strong>High-cell-density fed-batch cultivations of E. coli can reach > 2.5 g L^-1 production of functional anti-CD45 nanobodies when induction timing, production temperature, host strain genetics, and subcellular location of the final product are aligned. The highest yield, most uniform, and thermally stable anti-hCD45 NB preparation was obtained with signal-peptide-mediated periplasmic targeting.</p>","PeriodicalId":18582,"journal":{"name":"Microbial Cell Factories","volume":"25 1","pages":""},"PeriodicalIF":5.8,"publicationDate":"2026-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13551711/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148912820","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mitochondrial and plasma‑membrane transport‑based engineering enables industrial‑level isocitric acid production in Yarrowia lipolytica.","authors":"Eugenia Messina, Cosetta Ciliberti, Evgeniya Yuzbasheva, Serena Barile, Tigran Yuzbashev, Zbigniew Lazar, Ivan Laptev, Ferdinando Palmieri, Luigi Palmieri, Isabella Pisano, Gennaro Agrimi","doi":"10.1186/s12934-026-03098-4","DOIUrl":"10.1186/s12934-026-03098-4","url":null,"abstract":"<p><strong>Background: </strong>Isocitric acid (ICA) has recently attracted increasing interest because of its nutraceutical relevance and emerging biomedical potential. However, despite its value, industrial exploitation of ICA is still limited owing to the lack of cost‑effective and selective microbial production processes. Mitochondrial transporters play a pivotal role in controlling the pool sizes and fluxes of tricarboxylic acid (TCA) cycle intermediates by mediating their selective exchange across the inner mitochondrial membrane. Recently, we identified the mitochondrial carriers YlYhm2 and YlSfc1 in Yarrowia lipolytica as the specific transporters responsible for citric acid (CA) and ICA efflux, respectively, providing for the first time direct control over the selective secretion of these two organic acids. Building on this discovery, a transporter‑based metabolic engineering strategy was developed to establish a robust and highly selective ICA‑overproducing microbial platform.</p><p><strong>Results: </strong>Starting from a strain lacking the mitochondrial citrate carrier YlYHM2 and overexpressing the mitochondrial ICA exporter YlSFC1, ICA secretion was further enhanced through overexpression of the plasma‑membrane exporter YlCEX1. To further increase mitochondrial carbon availability feeding the TCA cycle, we overexpressed transporters capable of mediating net carbon import into mitochondria, including the dicarboxylate carriers YlOAC1 and YlDIC1, as well as the pyruvate carrier complex subunits YlMPC1/YlMPC2, either individually or in combination. Among these, YlOAC1 overexpression resulted in the most pronounced improvement, enabling production of 58.4 ± 2.4 g/L ICA with a molar yield of 0.62 mol/mol glucose in shake‑flask cultures. Fed‑batch bioreactor cultivation of this strain under nitrogen‑limited conditions yielded 152.76 ± 3.2 g/L ICA with a process selectivity of 95% (ICA/CA = 20), representing the highest titers and selectivity reported to date for a ICA producer.</p><p><strong>Conclusions: </strong>These results clearly demonstrate that precise manipulation of mitochondrial and plasma‑membrane transport processes constitutes a powerful and scalable strategy for redirecting carbon flux toward ICA production. This work establishes Y. lipolytica as a robust microbial chassis for industrial ICA manufacturing and highlights selective transport engineering as an effective complementary strategy alongside conventional enzyme centered metabolic engineering approaches, extending and reinforcing previously established roles of mitochondrial carriers in metabolic engineering.</p>","PeriodicalId":18582,"journal":{"name":"Microbial Cell Factories","volume":"25 1","pages":""},"PeriodicalIF":5.8,"publicationDate":"2026-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13602682/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149031013","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Harnessing the endophytic Clavispora lusitaniae for the biogenic synthesis of ethylene glycol-capped cerium oxide nanoparticles: a green approach to combat respiratory Pseudomonas aeruginosa.","authors":"Hoda S Nouh, Nessma A El-Zawawy, Shimaa El-Sapagh, Ebrahim M Shalamesh, Sally M Metwally","doi":"10.1186/s12934-026-03091-x","DOIUrl":"https://doi.org/10.1186/s12934-026-03091-x","url":null,"abstract":"<p><strong>Background: </strong>The utilization of endophytes as specialized microbial cell factories offers a sustainable and high-efficiency platform for the biosynthesis of functionalized nanomaterials. This study investigates the potential of a novel endophytic yeast, Clavispora lusitaniae, to produce cerium oxide nanoparticles (CeO₂NPs) and evaluates their efficacy against extensively drug-resistant (XDR) P. aeruginosa.</p><p><strong>Results: </strong>An endophytic yeast, C. lusitaniae, was isolated for the first time from the medicinal plant Artemisia judaica and employed for the biosynthesis of CeO₂NPs, followed by surface capping with ethylene glycol (EG) to modify the nanoparticle surface properties. The synthesized nanoparticles were characterized using UV-Vis, FTIR, XRD, TEM, and DLS. These analyses confirmed the formation of spherical EG-CeO₂NPs with an average size of 8-20 nm. EG-CeO₂NPs exhibited strong antibacterial activity against XDR P. aeruginosa strains, with a minimum inhibitory concentration ranging from 0.6 to 1.25 mg/mL. Furthermore, these nanoparticles demonstrated potent anti-biofilm efficacy, achieving reductions of up to 89%. Mechanistic investigations demonstrated that EG-CeO₂NPs disrupt bacterial cell membranes, leading to intracellular protein leakage and elevated lipid peroxidation (indicated by increased malondialdehyde levels). Furthermore, the expression levels of quorum sensing (e.g., lasR and rhlR) and virulence-associated genes (e.g., toxA and exoS) were markedly downregulated by up to 87% compared to untreated controls.</p><p><strong>Conclusions: </strong>This study establishes C. lusitaniae as a robust microbial cell factory for synthesizing functionalized CeO₂NPs with potent activity against XDR P. aeruginosa. Our results demonstrate the potential of microbial bioprocessing in engineering prospective nanotechnological platforms to combat antimicrobial resistance. However, further studies evaluating colloidal behavior under physiologically relevant conditions, mammalian-cell cytotoxicity, and in vivo efficacy are required before biomedical translation.</p>","PeriodicalId":18582,"journal":{"name":"Microbial Cell Factories","volume":"25 1","pages":""},"PeriodicalIF":5.8,"publicationDate":"2026-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13495233/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148795303","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}