Microbial Cell Factories最新文献

{"title":"Bacterial species-structure-property relationships of polyhydroxyalkanoate biopolymers produced on simple sugars for thin film applications.","authors":"Edward Attenborough, Farin Yazdan Parast, Reza Nosrati, Mark M Banaszak Holl, Leonie van 't Hag","doi":"10.1186/s12934-025-02833-7","DOIUrl":"10.1186/s12934-025-02833-7","url":null,"abstract":"<p><strong>Background: </strong>The bacterial production of polyhydroxyalkanoates (PHAs), a class of non-toxic, biodegradable, and bio-based polymers, has gained increasing attention as a sustainable alternative to petrochemical plastics. Among PHA producers, Cupriavidus necator H16 and Pseudomonas putida KT2440 are used for their ability to synthesise short- and medium-chain-length PHAs, respectively. While PHAs have been produced from simple hexoses like glucose and fructose, there remains a lack of systematic and integrated analysis linking carbon source, strain selection, monomer composition, and polymer crystallinity to blend behavior in ultrathin films.</p><p><strong>Results: </strong>PHB and mcl-PHA production using Cupriavidus necator H16 and Pseudomonas putida KT2440 on glucose and fructose were compared herein. C. necator accumulated PHB up to 60 wt% on fructose and 45 wt% on glucose, with high molecular weight (0.7-1.3 MDa), while P. putida produced mcl-PHA up to 22 wt% on fructose and 18 wt% on glucose, with lower molecular weight (46-47 kDa) and a C6 - C12 monomer profile. Notably, C. necator exhibited extreme cell elongation (up to 30 μm) during PHB accumulation on fructose. Extracted polymers were systematically solvent-blended at defined ratios (100:0, 80:20, 60:40, 40:60, and 20:80 PHB:mcl-PHA) and cast into ultrathin films (~ 20 μm) with varying composition. Crystallinity was modelled using a Gaussian fitting approach on FTIR spectra via custom MATLAB code, enabling localised phase analysis and offering a rapid alternative to DSC for thin film crystallinity estimation. While film blends exhibited tunable crystallinity and multiple melting transitions, elongation at break was consistent across compositions, with increases observed at higher mcl-PHA content.</p><p><strong>Conclusions: </strong>This study provides a systematic comparison of PHAs from C. necator H16 and P. putida KT2440 grown on common hexoses, with full characterisation of monomer composition, molecular weight, and thermal behaviour to guide thin film bioplastic design. Blending PHB and mcl-PHA in ultrathin films revealed reduced melting points and crystallinity, likely due to reduced crystal size from film thickness constraints. This work offers a comparative reference for microbial PHA production and presents a strategy to design bioplastics with tunable properties for temperature-responsive packaging and drug delivery applications.</p>","PeriodicalId":18582,"journal":{"name":"Microbial Cell Factories","volume":"24 1","pages":"204"},"PeriodicalIF":4.9,"publicationDate":"2025-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12439366/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145075706","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":"Multilocus identification and genetic enhancement of Trichoderma spp. for entomopathogenic activity against Spodoptera littoralis.","authors":"Nehal A Atta, Abdelmegid I Fahmi, Khalid S Abdel-Lateif, Hesham H Nagaty, Enas M Abd El-Ghany","doi":"10.1186/s12934-025-02834-6","DOIUrl":"10.1186/s12934-025-02834-6","url":null,"abstract":"<p><strong>Background: </strong>The Egyptian cotton leafworm (Spodoptera littoralis) is a highly destructive, pesticide-resistant pest affecting over 80 economically important crops across the Mediterranean and African regions. While chemical insecticides offer temporary relief, their long-term use poses environmental and health risks, and resistance development reduces their effectiveness. Biological control using entomopathogenic fungi, particularly Trichoderma spp., offers a sustainable alternative. Traditionally, it is used against plant pathogens, Trichoderma harzianum, T. viride, T. asperellum, and T. longibrachiatum have also shown insecticidal potential through the production of compounds like peptaibols, gliotoxins, and chitinases, and by inducing systemic resistance in plants. However, the entomopathogenic potential of native Trichoderma isolates in Egypt remains undiscovered, and field performance is often inconsistent. This study aims to identify and evaluate native Trichoderma strains against S. littoralis and enhance their biocontrol efficacy through interspecific protoplast fusion a promising parasexual technique for strain improvement.</p><p><strong>Results: </strong>Multilocus sequence analysis targeting the tef1-α and rpb2 genes identified the isolates as T. harzianum, T. asperellum, and T. longibrachiatum. Phylogenetic analysis clustered the isolates into three well-distinctive clades corresponding to these species. Among the tested isolates, Tricho19 (T. longibrachiatum), Tricho5 (T. asperellum), and Tricho30 (T. harzianum) demonstrated the highest extracellular chitinase activity and larval mortality in oral bioassays against S. littoralis. Interspecific protoplast fusion led to the generation of fusants with significantly enhanced chitinase production and insecticidal activity relative to their parental strains. Greenhouse assays confirmed the superior performance of fusant Fus8, which exhibited the highest larval mortality and antifeedant activity, closely approaching the efficacy of a chemical insecticide.</p><p><strong>Conclusion: </strong>Interspecific protoplast fusion significantly improved the entomopathogenic performance of Trichoderma strains against S. littoralis. The enhanced activity of fusant strains, particularly Fus8, highlights the potential of this cost-effective strategy to generate improved biocontrol agents. These findings contribute to the development of sustainable pest management alternatives that can reduce reliance on chemical pesticides in agriculture.</p>","PeriodicalId":18582,"journal":{"name":"Microbial Cell Factories","volume":"24 1","pages":"202"},"PeriodicalIF":4.9,"publicationDate":"2025-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12427115/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145040698","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":"Production, optimization and characterization of esterase isolated from a new endophytic Trichoderma afroharzianum strain AUMC 16,433 and its applications in dye decolorization.","authors":"Yehia A-G Mahmoud, Nisrin S Alamin, Tarek M Mohamed, Nesma A El-Zawawy, Maha M Salem","doi":"10.1186/s12934-025-02832-8","DOIUrl":"10.1186/s12934-025-02832-8","url":null,"abstract":"<p><strong>Background and aim: </strong>Synthetic dyes in the textile industry pose risks to human health and environmental safety. The current study aims to examine the efficacy of a novel esterase derived from an endophyte fungus in decolorizing diverse dyes, focusing on its production, purification, optimization, and characterization.</p><p><strong>Results: </strong>Trichoderma afroharzianum AUMC16433, a novel fungal endophyte with esterase-producing ability, was first detected from the cladodes of Opuntia ficus indica by ITS-rRNA sequencing. Furthermore, several fermentation variables that augment esterase production were improved by utilising the Plackett-Burman design and RSM. Ammonium sulphate precipitation at 60% and Sephacryl S300 HR gel filtration were employed to purify the isolated esterase to a specific activity of 1372.1 U/mg with a 2.29-fold increase and a recovery of 42.87%. The enzyme's molecular weight was ascertained to be 43 kDa via SDS-PAGE. The isolated esterase revealed peak activity at 40 °C and pH 8. The kinetic characteristics of esterase were Vmax = 2.717 U/mL and Km = 3.33 mM. The half-life time was 54.4% at 50 °C after 4 h, and the enzyme still retained 14.7% of its activity after 24 h at 50 °C. Esterase decolorized several synthetic dyes used industrially, with the highest decolorization rate in malachite green after 24 h with 66%, and successfully degraded both bromothymol blue and tartrazine with 65.5% and 65.3%, respectively, in the same time frame. Crystal violet and methyl red showed moderate decolorization, with decolorization rates of 57.1% and 43.1%, respectively.</p><p><strong>Conclusions: </strong>The esterase enzyme isolated for the first time from the new endophytic Trichoderma afroharzianum has a high dyes decolorization potential, which offers it a sustainable strategy for addressing environmental contamination issues.</p>","PeriodicalId":18582,"journal":{"name":"Microbial Cell Factories","volume":"24 1","pages":"201"},"PeriodicalIF":4.9,"publicationDate":"2025-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12418644/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145030146","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":"Amesia nigricolor, a novel endophyte of Encephalartos bubalinus, exhibiting a robust taxol biosynthetic stability: chemical characterization and biological activities.","authors":"Asmaa Gamal, Ashraf S A El-Sayed, Eman Fikry, Nora Tawfeek, Azza M El-Shafae, Maher M El-Domiaty","doi":"10.1186/s12934-025-02827-5","DOIUrl":"10.1186/s12934-025-02827-5","url":null,"abstract":"<p><p>Diminishing the productivity of Taxol by the potential fungi with storage is the key hurdle that impedes their applications to be an industrial platform for Taxol production. Thus, exploring of a fungal isolate with a reliable robustness for Taxol biosynthesis is the objective of this study. Although, Encephalartos bubalinus has diverse ethnopharmaceutical properties, however, the identity of its endophytic fungi remains poorly explored. Therefore, the endophytic fungi inhabiting this plant has been isolated and characterized, and their Taxol productivity was assessed. Amesia nigricolor OR364127.1, an endophyte of E. bubalinus, was characterized as the potent biologically active and Taxol producer (105 μg/l). The sample identity was resolved from the HPLC, FT-IR and MS/MS analysis, with the molecular mass/ fragmentation pattern was identical to authentic one. The extracted Taxol of A. nigricolor had a strong activity against the HepG2 (IC₅₀ 19 nM) and MCF7 (IC₅₀ 23 nM) with a selectivity index 13.2 and 11.9 to the normal Vero cells. Taxol of A. nigricolor had a powerful anti-wound healing, and apoptotic properties, with ability to stop the G2/M cell cycle, ensuring their consistent biological activity to the authentic one. The Taxol yield by A. nigricolor was enhanced by 2 folds (205.2 μg/l), with the statistical bioprocessing by CCD. The half-life time for production of Taxol by A. nigricolor was more than 10 months, that being higher than those reported for various Taxol-producing fungi, ensuring the relative stability of the biosynthetic machinery of Taxol by A. nigricolor with storage as solid cultures at 4°C. A relative restoring to the Taxol productivity by A. nigricolor was noticed with ethylacetate extract of E. bubalinus, ensuring the presence of chemical signals inducing Taxol productivity by A. nigricolor. To the best of our knowledge, this is the first recorded endophytic fungus \"A. nigricolor EFBL-AG\" with a relative stability of Taxol biosynthetic machinery.</p>","PeriodicalId":18582,"journal":{"name":"Microbial Cell Factories","volume":"24 1","pages":"200"},"PeriodicalIF":4.9,"publicationDate":"2025-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12406444/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144993193","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":"Identification of novel Gramicidin S analogs from Aneurinibacillus aneurinilyticus isolated from corn steep liquor with potential antifungal activity.","authors":"Ksenia Lvova, Manuel Marcos, Benita Pérez-Cid, Xanel Vecino, José Manuel Cruz, Ana Belén Moldes","doi":"10.1186/s12934-025-02835-5","DOIUrl":"10.1186/s12934-025-02835-5","url":null,"abstract":"<p><p>In the existing literature, there is ample information available concerning the analogs constituting linear Gramicidin (Gramicidin A). However, the literature lacks information regarding the microbial production of cyclic Gramicidin S (GR-S) and the study of its analogs' amino acid composition. Thus, in this study, GR-S was produced by Aneurinibacillus aneurinilyticus, isolated from corn steep liquor (CSL) and grown in synthetic or CSL-based medium. The extract was obtained from microbial biomass and underwent analysis with ultra performance liquid chromatography coupled with electrospray ionization tandem mass spectrometry (UPLC-ESI-MS/MS) to ascertain the presence and abundance of GR-S clusters, identifying five GR S analogs. Hence, when using a synthetic medium, the dominant cluster compromised the sequence Val-Orn-Leu-Phe-Pro-Val-Orn-Leu-Phe-Pro. Contrarily, when using CSL-based medium, the main analog was composed of Val-Orn-Leu-Phe-Pro-Val-Lys-Leu-Phe-Pro. In the remaining analogs, one or both Ornithine (Orn) residues were replaced by Lysine (Lys) or diaminobutyric acid (D-Dab). Microscopy images revealed that the use of CSL-based medium resulted in a lower yield of GR-S and a higher accumulation of vacuoles compatible with the presence of intracellular polyhydroxyalkanoates (PHA) when comparing with TSB medium. The antifungal assay revealed a superior conidial inhibition activity of GR-S extract under evaluation against Aspergillus brasiliensis in comparison to the commercial GR-S. Consequently, it can be concluded that this novel microbial GR-S extract exhibits favorable antifungal activity, positioning it as a promising candidate for antimicrobial treatments. However, further research is necessary to address the global challenge of antibiotic-resistant pathogens.</p>","PeriodicalId":18582,"journal":{"name":"Microbial Cell Factories","volume":"24 1","pages":"199"},"PeriodicalIF":4.9,"publicationDate":"2025-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12403468/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144961054","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":"Optimising CO₂ level and light quality for enhanced whole-cell biotransformation reactions in Synechocystis sp. PCC 6803.","authors":"Michal Hubáček, Lauri Nikkanen, Yagut Allahverdiyeva","doi":"10.1186/s12934-025-02828-4","DOIUrl":"10.1186/s12934-025-02828-4","url":null,"abstract":"<p><p>Cyanobacteria are emerging as a promising platform for whole-cell biotransformation, harnessing solar energy to drive biocatalytic reactions through recombinant enzymes. However, optimisation remains challenging due to the complexity of the cyanobacterial metabolism and the regulatory framework in which heterologous enzymes operate. While many enzymes have been deployed for light-driven whole-cell biotransformations, the different experimental conditions used between studies make direct comparison and systematic improvement difficult. We investigated the performance of two Baeyer-Villiger monooxygenases (BVMO) and the ene-reductase YqjM, heterologously expressed in the model cyanobacterium Synechocystis sp. PCC 6803, under varying growth and production conditions. NADPH and O₂ availability, along with protein accumulation levels, were examined as potential bottlenecks affecting enzyme activity. A 4-fold improvement in specific activity of BVMOs was achieved when cultures were grown under elevated CO₂, and a 2-fold improvement was observed under broad white light enriched with red and blue wavelengths. Elevated CO₂ cultivations enhanced BVMO protein accumulation, while YqjM levels and activity remained unchanged. In contrast, the modified light spectrum led to a non-significant increase in BVMO accumulation but significantly enhanced specific activity under ambient CO₂ conditions. These findings demonstrate the importance of a tailored optimisation strategy for each enzyme in cyanobacterial light-driven whole-cell biotransformation and shed light on the complex physiological responses of production strains to environmental conditions.</p>","PeriodicalId":18582,"journal":{"name":"Microbial Cell Factories","volume":"24 1","pages":"198"},"PeriodicalIF":4.9,"publicationDate":"2025-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12398983/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144961028","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":"Mechanisms of magneto-coagulation of the sludge in activated sludge bulking processes.","authors":"Ramin Khoshniyat, Ghorban Asgari, Esmaeil Ghahramani, Glen T Daigger","doi":"10.1186/s12934-025-02807-9","DOIUrl":"https://doi.org/10.1186/s12934-025-02807-9","url":null,"abstract":"","PeriodicalId":18582,"journal":{"name":"Microbial Cell Factories","volume":"24 1","pages":"197"},"PeriodicalIF":4.9,"publicationDate":"2025-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12398163/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144961056","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":"Bacterial cellulose doped with ZnO as a multifunctional bioactive platform for curcumin and propolis immobilization: synthesis, characterization, and wound healing potential.","authors":"Ghada E Dawwam, Naglaa Salem El-Sayed, Mona T Al-Shemy","doi":"10.1186/s12934-025-02826-6","DOIUrl":"https://doi.org/10.1186/s12934-025-02826-6","url":null,"abstract":"<p><p>Bacterial cellulose (BC)-based dressings exhibit favorable hydrogel characteristics, including high biocompatibility, moisture regulation, and mechanical adaptability, making them suitable candidates for biomedical applications. In this study, an integrated approach was employed to develop multifunctional, bioactive bionanocomposites. A cellulose-producing bacterial strain, Limosilactobacillus fermentum 6BC (accession number OM978241.1), was isolated from spoiled grapes and identified through 16 S rRNA gene sequencing. The structural and chemical characteristics of the synthesized BC were analyzed using Transmission electron microscopy (TEM), scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD). To enhance the biological functionality of BC, zinc oxide (ZnO) nanoparticles were incorporated via a sono-coprecipitation method to produce ZnO-decorated BC (BCZO). The resulting BCZO was subsequently integrated into a hydroxypropyl ethyl cellulose (HPEC) matrix, forming a bionanoplatform designed for the immobilization of bioactive agents, specifically curcumin (Cc) and propolis extract (Pp). TEM was used to examine the nanoscale distribution of ZnO, while FTIR, XRD, SEM, and EDS were employed to characterize the composite structure and confirm drug incorporation. The fabricated scaffolds were further subjected to comprehensive antimicrobial, antioxidant, cytocompatibility, and in vitro wound healing assessments to evaluate their biological performance. The antimicrobial assays demonstrated effective inhibition of L. monocytogenes, S. aureus, E. coli, Salmonella sp., and the fungus C. albicans. The bionanoplatforms also exhibited concentration-dependent antioxidant activity in DPPH and ABTS assays (ascorbic acid as control). The cytocompatibility tests on human skin fibroblasts (HFB-4) showed excellent cell viability across all formulations. Among them, Cc/Pp50@BCZO/HPEC displayed the exciting antimicrobial and antioxidant performance, coupled with desirable cytocompatibility. Thus this study offers a systematic framework for engineering cellulose-based bioplatforms as bioactive materials for potential drug delivery and wound-healing applications.</p>","PeriodicalId":18582,"journal":{"name":"Microbial Cell Factories","volume":"24 1","pages":"196"},"PeriodicalIF":4.9,"publicationDate":"2025-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12376435/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144961030","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":"Glyphosate bioremediation using a newly isolated Bacillus albus strain F9D: mechanisms and kinetic studies.","authors":"Wen-Juan Chen, Mingqiu Liu, Shao-Fang Chen, Yuming Zhang, Haoran Song, Maman Hassan Abdoulahi, Kalpana Bhatt, Sandhya Mishra, Mohamed A Ghorab, Wenping Zhang, Shaohua Chen","doi":"10.1186/s12934-025-02758-1","DOIUrl":"10.1186/s12934-025-02758-1","url":null,"abstract":"","PeriodicalId":18582,"journal":{"name":"Microbial Cell Factories","volume":"24 1","pages":"195"},"PeriodicalIF":4.9,"publicationDate":"2025-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12374316/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144961079","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":"Increasing lipid accumulation in Chlamydomonas by serial knocking out of DYRKP1 kinase and ADP-glucose pyrophosphorylase.","authors":"Minjae Kim, Ji Yeon Kim, Kyong Ha Han, Hyeon Ho Shin, EonSeon Jin","doi":"10.1186/s12934-025-02824-8","DOIUrl":"https://doi.org/10.1186/s12934-025-02824-8","url":null,"abstract":"<p><p>Microalgae are promising sustainable feedstocks for biodiesel production. Among the primary carbon reservoirs in microalgae, starch and lipids are the main targets for metabolic engineering aimed at enhancing productivity. Redirecting carbon flux from starch toward lipid biosynthesis has been considered an effective strategy to improve lipid yield, and manipulating upstream regulators may allow broader control over metabolic networks. DYRKP1, a plant-specific dual-specificity tyrosine-phosphorylation-regulated kinase conserved in photosynthetic eukaryotes, has been implicated in regulating intracellular carbon partitioning. In this study, we investigated the physiological and metabolic effects of DYRKP1 deficiency in a cell-wall-less strain of Chlamydomonas reinhardtii. To further enhance lipid accumulation, we additionally knocked out ADP-glucose pyrophosphorylase (AGP), a key enzyme involved in starch biosynthesis. The total fatty acid content of DYRKP1-AGP double knockout (dKO) mutants was higher than that of their parental strain (CC4349) under both nitrogen-replete and deplete conditions, and was even 1.2-fold higher than that of the AGP single knockout (agp) mutant under nitrogen-deplete conditions. The DYRKP1 single knockout mutants exhibited fatty acid composition similar to the parental strain, regardless of nitrogen depletion. The fatty acid composition of the dKO mutants resembled that of the agp mutant under nitrogen-replete conditions, but diverged upon nitrogen starvation, suggesting a conditional interaction between upstream regulation and metabolic flux. This finding implies that disrupting upstream regulators like DYRKP1 may offer limited additional benefit when key downstream bottlenecks, such as starch biosynthesis, are already removed. Overall, our study underscores the layered complexity of carbon partitioning in C. reinhardtii and the importance of context-dependent metabolic regulation in optimizing lipid production.</p>","PeriodicalId":18582,"journal":{"name":"Microbial Cell Factories","volume":"24 1","pages":"194"},"PeriodicalIF":4.9,"publicationDate":"2025-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12372370/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144961099","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}