Frontiers in Bioengineering and Biotechnology最新文献

{"title":"Extracellular vesicles as vital players in drug delivery: a focus on clinical disease treatment.","authors":"Tiangang Chen, Dan Chen, Wanting Su, Jianlan Liang, Xiangning Liu, Mingxiang Cai","doi":"10.3389/fbioe.2025.1600227","DOIUrl":"https://doi.org/10.3389/fbioe.2025.1600227","url":null,"abstract":"<p><p>Extracellular vesicles (EVs), a diverse population of bilayer lipid-membrane vesicles secreted by cells, have emerged as ideal drug carriers due to their efficient cellular uptake and targeted delivery capabilities. Advancements in medical and bioengineering collaborations have enabled EVs to be engineered for specific marker expression or therapeutic cargo transport, positioning them as a promising modality for treating cancer, neurological disorders, cardiovascular diseases, and beyond. EV-based drug delivery strategies offer distinct advantages, including facilitation of intercellular communication and immune modulation, high biocompatibility and stability, the ability to traverse the blood-brain barrier, and potential synergistic interactions with encapsulated therapeutics to enhance efficacy. This review explores EV isolation and scalable production, emphasizing cost-effective and reproducible manufacturing strategies, cargo-loading methodologies, and therapeutic applications. Additionally, the current landscape of EV-based targeted drug delivery, clinical translation prospects, and prevailing challenges are examined to provide a comprehensive perspective on their potential in drug delivery systems.</p>","PeriodicalId":12444,"journal":{"name":"Frontiers in Bioengineering and Biotechnology","volume":"13 ","pages":"1600227"},"PeriodicalIF":4.3,"publicationDate":"2025-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12116468/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144173533","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Prediction of post-Schroth Cobb angle changes in adolescent idiopathic scoliosis patients based on neural networks and surface electromyography.","authors":"Shuguang Yin, Jiangang Chen, Peng Yan","doi":"10.3389/fbioe.2025.1570022","DOIUrl":"https://doi.org/10.3389/fbioe.2025.1570022","url":null,"abstract":"<p><strong>Introduction: </strong>To develop a temporal-convolutional-LSTM (TCN-LSTM) hybrid model integrating surface electromyography (sEMG) signals for forecasting post-Schroth Cobb angle progression in adolescent idiopathic scoliosis (AIS) patients, thereby offering accurate feedback for personalized treatment.</p><p><strong>Methodology: </strong>A total of 143 AIS patients were included. A systematic Schroth exercise training program was designed. sEMG data from specific muscles and Cobb angle measurements were collected. A neural network model integrating Temporal Convolutional Network (TCN), Long Short-Term Memory (LSTM) layers, and feature vectors was constructed. Four prediction models were compared: TCN-LSTM hybrid model, TCN, LSTM, and Support Vector Regression (SVR).</p><p><strong>Results: </strong>The TCN-LSTM hybrid model demonstrated superior performance, with Cobb angle-Thoracic (Cobb Angle-T) prediction accuracy reaching R² = 0.63 (baseline) and 0.69 (Week 24), achieving overall R² = 0.74. For Cobb angle-Lumbar (Cobb Angle-L), accuracy was R² = 0.61 (baseline) and 0.65 (Week 24), with overall R² = 0.73. The SVR model showed lowest performance (R² < 0.12).</p><p><strong>Conclusion: </strong>The TCN-LSTM hybrid model can precisely predict Cobb angle changes in AIS patients during Schroth exercises, especially in long-term predictions. It provides real-time feedback for clinical treatment and contributes to optimizing treatment plans, presenting a novel prediction approach and reference basis for evaluating the effectiveness of Schroth correction exercises in AIS patients.</p>","PeriodicalId":12444,"journal":{"name":"Frontiers in Bioengineering and Biotechnology","volume":"13 ","pages":"1570022"},"PeriodicalIF":4.3,"publicationDate":"2025-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12116612/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144172813","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis and assessment of biomedical scientists' needs for clinical laboratory: activity-based management as an evaluation methodology.","authors":"Claudia Bizzoni, Gavino Napolitano, Simonetta Cesa, Luca Sacella, Caterina Bianciardi, Cosimo Ottomano, Rita Mancini, Giorgio Da Rin","doi":"10.3389/fbioe.2025.1569800","DOIUrl":"https://doi.org/10.3389/fbioe.2025.1569800","url":null,"abstract":"<p><strong>Introduction: </strong>Healthcare systems have to protect citizens' health by developing models combining concepts of efficiency, effectiveness and quality of care. The post-Covid-19 pandemic context has highlighted the relevance of efficiently managing and allocating human resources. In this scenario, the analysis and calculation of personnel needs take on strategic importance. The project aims to suggest a methodology to define the needs of Biomedical Scientists. The goal is to create a standard model adaptable to different contexts.</p><p><strong>Methods: </strong>This project, developed in cooperation with the Italian Society of Clinical Biochemistry and Clinical Molecular Biology, has created a new format following the \"Activity Based Management\" approach. It is characterized by continuous improvements, based on analysis of processes, broken down into sub-processes and activities. After the phase of format development, a phase of application to different contexts, such as biochemistry and the hematology sectors, followed.</p><p><strong>Results: </strong>The suggested methodology allows to estimate the number of Full Time Equivalents necessary for the management of the laboratory processes. Furthermore, an objective and analytical data is obtained, because it is based on timely numerical surveys that included productivity and execution times of the different activities.</p><p><strong>Discussion: </strong>Using the format had a relevant impact on the analysis of the processes, their efficiency, and their possible improvement. This method allowed to evaluate and improve the analytical and \"extra-production\" activities, often underestimated but having a decisive role in the process. The proposed format can be considered a valid tool for laboratory managers to analyze and evaluating the needs of Biomedical Scientists in the laboratory. Activity Based Management allowed us to obtain precise and objective data and, at the same time, to focus on the main objective of any clinical laboratory: to create value for the patient by supporting diagnosis and treatment of paths through safe and reliable laboratory tests, which depends on a correct allocation of human resources.</p>","PeriodicalId":12444,"journal":{"name":"Frontiers in Bioengineering and Biotechnology","volume":"13 ","pages":"1569800"},"PeriodicalIF":4.3,"publicationDate":"2025-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12106407/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144157471","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Patient-specific dynamic reference frame for navigation-assisted surgery in mandible: a novel noninvasive technical method.","authors":"Jinyang Wu, Lai Jiang, Yingqi Cheng, Wenbin Zhang, Jianfei Zhang, Xiaoyan Gao, Xiaofeng Xu, Shilei Zhang","doi":"10.3389/fbioe.2025.1577321","DOIUrl":"https://doi.org/10.3389/fbioe.2025.1577321","url":null,"abstract":"<p><strong>Objectives: </strong>Computer-assisted navigation has been established as a valuable tool in oral and craniomaxillofacial surgery. However, the steep learning curve associated with mandibular navigation surgery has hindered its widespread adoption. This study introduces a non-invasive, convenient, and accurate navigation method for mandibular surgery and evaluates its clinical effectiveness.</p><p><strong>Methods: </strong>A modified patient-specific dynamic reference frame (PS-DRF) was designed and fabricated based on the patient's lower jaw dental cast, integrating navigation technology with 3D printing. During surgery, the PS-DRF was securely affixed to the lower dentition, enabling automatic pair-point registration through fiducial localization via a navigation probe. The surgical procedure was conducted under real-time navigation guidance.</p><p><strong>Results: </strong>Preoperative registration and intraoperative navigation were successfully achieved in this case. The navigation-guided mandibular surgery was completed without complications. Postoperative superimposition of the simulated virtual model and the actual surgical outcome demonstrated high accuracy, with a deviation of less than 2 mm.</p><p><strong>Conclusion: </strong>The PS-DRF system offers a convenient, effective, and adaptable approach by integrating navigation technology with 3D printing. This method has the potential to simplify navigation-assisted mandibular surgery and facilitate the broader clinical implementation of computer-assisted navigation in maxillofacial procedures.</p>","PeriodicalId":12444,"journal":{"name":"Frontiers in Bioengineering and Biotechnology","volume":"13 ","pages":"1577321"},"PeriodicalIF":4.3,"publicationDate":"2025-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12106423/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144157483","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dual-functional titanium implants via polydopamine-mediated lithium and copper co-incorporation: synergistic enhancement of osseointegration and antibacterial efficacy.","authors":"Jun Li, Bo Jiang, Liu Yang, Pu Zhang, Jingwen Wu, Yalan Yang, Yan Yang, Guiling Wang, Jie Chen, Ling Zhang, Shiqin Huang, Lingli Zhang, En Zhang","doi":"10.3389/fbioe.2025.1593545","DOIUrl":"https://doi.org/10.3389/fbioe.2025.1593545","url":null,"abstract":"<p><strong>Introduction: </strong>Orthopedic implant failure due to inadequate osseointegration and infection remains a critical challenge. To address this, we engineered a polydopamine (PDA)-mediated dual-functional platform for lithium (Li⁺) and copper (Cu²⁺) co-incorporation on titanium alloy (Ti6Al4V) implants, aiming to synergize osteogenic and antibacterial properties through a scalable surface modification strategy.</p><p><strong>Methods: </strong>PDA coatings were polymerized onto polished Ti64 substrates, followed by sequential immersion in LiCl (800 μM) and CuCl₂ (10 μM) solutions to construct Li⁺/Cu²⁺ co-doped surfaces (PDA@Li 800-Cu 10). In vitro assays assessed MC3T3-E1 pre-osteoblast proliferation (CCK-8), osteogenic differentiation (ALP activity, RT-PCR for <i>ALP/Axin2</i>), and antibacterial activity against S. aureus and E. coli (live/dead staining, CFU assays). In vivo efficacy was evaluated in a rat femoral defect model via micro-CT and histology.</p><p><strong>Results and discussion: </strong>Li⁺-functionalized surfaces (PDA@Li 800) enhanced osteoblast proliferation and osteogenesis via Wnt/β-catenin activation. Cu²⁺-loaded coatings (PDA@Cu 10) eradicated >99% bacteria but moderately suppressed osteogenic markers. The dual-doped PDA@Li 800-Cu 10 surface resolved this bioactivity conflict, maintaining antibacterial efficacy comparable to PDA@Cu 10 while elevating the osteogenic capacity of Cu²⁺-only modified surfaces. In vivo, dual-modified implants eliminated bacterial colonization within 72 h and significantly increased peri-implant bone volume (BV/TV) in comparison to Ti64 controls, outperforming PDA-only counterparts. By harmonizing Li-driven osteoinduction and Cu-mediated bactericidal action through a scalable PDA platform, this work advances a transformative strategy for next-generation orthopedic and dental implants, simultaneously addressing infection risks and bone regeneration demands.</p>","PeriodicalId":12444,"journal":{"name":"Frontiers in Bioengineering and Biotechnology","volume":"13 ","pages":"1593545"},"PeriodicalIF":4.3,"publicationDate":"2025-05-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12104301/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144149849","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Microfluidic transection injury and high-shear thrombus formation demonstrate increased hemostatic efficacy of cold-stored platelets and <i>in vitro</i> resuscitation in induced coagulopathy models.","authors":"Emily P Mihalko, Refael Munitz, Devin M Dishong, Skye Clayton, Susan M Shea","doi":"10.3389/fbioe.2025.1568113","DOIUrl":"https://doi.org/10.3389/fbioe.2025.1568113","url":null,"abstract":"<p><p>Hemostatic resuscitation is an essential aspect of treating traumatic bleeding. Trauma-induced coagulopathy is a multifactorial disorder that can lead to increased transfusion requirements. However, little is known about the interplay between coagulopathies and stored blood products used for hemostatic resuscitation, which themselves acquire dysfunction in the form of a storage lesion. Physiologically relevant models can aid in the study of trauma and hemostatic resuscitation by incorporating important aspects such as biological surfaces and flow regimes that mimic injury. This study aims to evaluate the contribution of platelet products under varying storage conditions in coagulopathic states. This study utilized microfluidic platforms of high shear, a flow regime relevant to injury, including a stenotic straight channel and a severe transected vessel injury device. Apheresis platelet products were collected from healthy volunteers, stored at room temperature (RT) or cold-stored (CS) (1°C-6°C), and tested for product cell count and intrinsic product function in a high-shear stenotic microfluidic device across storage days (D2, D5, and D7 for RT; D2, D5, D7, D14, and D21 for CS). Hemostatic resuscitation efficacy of products was assessed using induced coagulopathy models of dilution and thrombocytopenia (TP). <i>In vitro</i> hemostatic resuscitation was assessed in both the stenotic straight channel for kinetic platelet contributions and the transected-vessel injury device, using blood loss and clot composition as endpoints. CS products conserved inherent function despite decreasing platelet counts through storage D7. When mixed with coagulopathic blood, D2 RT products did not show hemostatic benefit in the dilutional coagulopathy (DC) model. However, both D2 RT and CS showed hemostatic benefits in the thrombocytopenia model. CS products (D5 and D7) also showed an enhanced ability to recruit recipient platelets in the thrombocytopenia model compared to RT. Overall, this study highlights disparate responses associated with product storage duration and temperature, indicating the need to further evaluate hemostatic resuscitation efficacy under flow in pathologically relevant models to guide transfusion practices.</p>","PeriodicalId":12444,"journal":{"name":"Frontiers in Bioengineering and Biotechnology","volume":"13 ","pages":"1568113"},"PeriodicalIF":4.3,"publicationDate":"2025-05-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12104287/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144149852","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Innovative applications of silicon dioxide nanoparticles for targeted liver cancer treatment.","authors":"Tiantian Fu, Boshi Duan, Peng Sun, Wei Ma, Tianzuo Wang, Tianyou Wang, Zhuang Tong, Yue Wang","doi":"10.3389/fbioe.2025.1595772","DOIUrl":"https://doi.org/10.3389/fbioe.2025.1595772","url":null,"abstract":"<p><p>Liver cancer remains a major global health challenge, characterized by high mortality and limited treatment efficacy. Conventional therapies, including chemotherapy, immunotherapy, and viral vectors, are hindered by systemic toxicity, drug resistance, and high costs. Silica nanoparticles (SiO₂NPs) have emerged as promising platforms for liver cancer therapy, offering precise drug delivery, stimuli-responsive release, and integrated diagnostic-therapeutic capabilities. This review critically examines the potential of SiO₂NPs to overcome these therapeutic limitations. Notable advances include their high drug-loading capacity, customizable surface modifications, and dual-responsive systems (pH/redox/NIR-II) that enable >90% tumor-specific drug release. Preclinical studies have demonstrated synergistic efficacy in combination therapies. Additionally, theranostic SiO₂NPs enable MRI-guided tumor delineation and real-time treatment monitoring. Despite promising results, challenges remain in long-term biosafety, scalable synthesis, and regulatory compliance. Early-phase clinical trials, including those using NIR-II-responsive platforms, highlight their translational potential but underscore the need for further validation of toxicity profiles and manufacturing standards. Future research should focus on optimizing combinatory treatment strategies, scaling up production, and aligning with evolving regulatory frameworks. By bridging nanomaterial innovation with clinical applications, SiO₂NPs offer unparalleled potential for advancing precision oncology in hepatocellular carcinoma.</p>","PeriodicalId":12444,"journal":{"name":"Frontiers in Bioengineering and Biotechnology","volume":"13 ","pages":"1595772"},"PeriodicalIF":4.3,"publicationDate":"2025-05-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12104587/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144149850","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Innovative hydrogels in cutaneous wound healing: current status and future perspectives.","authors":"Prasad Sawadkar, Ferdinand Lali, Elena Garcia-Gareta, Beatriz Gil Garrido, Abdullah Chaudhry, Priya Matharu, Christos Kyriakidis, Karin Greco","doi":"10.3389/fbioe.2025.1454903","DOIUrl":"https://doi.org/10.3389/fbioe.2025.1454903","url":null,"abstract":"<p><p>Chronic wounds pose a substantial burden on healthcare systems, necessitating innovative tissue engineering strategies to enhance clinical outcomes. Hydrogels, both of natural and synthetic origin, have emerged as versatile biomaterials for wound management due to their structural adaptability, biocompatibility, and tunable physicochemical properties. Their hydrophilic nature enables efficient nutrient transport, waste removal, and cellular integration, while their malleability facilitates application to deep and irregular wounds, providing an optimal microenvironment for cell adhesion, proliferation, and differentiation. Extracellular matrix (ECM)- based hydrogels retain bioactive molecules that support cellular infiltration, immune modulation, and tissue remodelling, making them highly effective scaffolds for growth factor delivery and regenerative therapies. Additionally, their injectability and potential for <i>in situ</i> polymerization enable minimally invasive applications, allowing on-demand gelation at target sites. By modifying their mechanical properties through crosslinking, hydrogels can achieve enhanced structural stability, prolonged degradation control, and improved surgical handling, optimizing their functionality in dynamic wound environments. This review outlines current approaches to skin tissue engineering, examining the biomaterials employed in hydrogel design, their limitations, and their interactions with host tissues. Furthermore, it highlights the emerging potential of functionalized injectable hydrogels, particularly those engineered for controlled drug release, enhanced bioactivity, and patient-specific therapeutic applications. These hydrogels offer a transformative platform for advanced wound care and regenerative medicine.</p>","PeriodicalId":12444,"journal":{"name":"Frontiers in Bioengineering and Biotechnology","volume":"13 ","pages":"1454903"},"PeriodicalIF":4.3,"publicationDate":"2025-05-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12104307/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144149851","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Shaping the future of tobacco through microbial insights: a review of advances and applications.","authors":"Wei Hu, Jiaxing Yuan, Jiaxiang Fei, Kaleem Imdad, Pengfei Yang, Shen Huang, Duobin Mao, Jing Yang","doi":"10.3389/fbioe.2025.1548323","DOIUrl":"https://doi.org/10.3389/fbioe.2025.1548323","url":null,"abstract":"<p><p>Over the past 20 years, researchers have used multi-omics techniques to study microbial diversity and metabolic function on tobacco leaves. The unique metabolic function of tobacco microorganisms has attracted extensive attention from researchers, which is an important research field in tobacco industry to improve the intrinsic quality of tobacco leaf with microbial agents. The microorganisms are particularly rich on the surface of tobacco leaf, and their metabolic function is closely related to the change of tobacco leaf chemical composition. Some microorganisms have important metabolic functions, such as: degrading macromolecular and harmful substances in tobacco leaves, and they have different degradation rates and pathways for the substances. At present, many functions of tobacco leaf microorganisms have not been fully verified and analyzed. In the future, more novel culture methods are needed to screen and isolate microorganisms on the surface of tobacco leaves, deeply tap their metabolic potential, explore the application value of microorganisms in the tobacco industry, and further promote the innovation and development of the industry.</p>","PeriodicalId":12444,"journal":{"name":"Frontiers in Bioengineering and Biotechnology","volume":"13 ","pages":"1548323"},"PeriodicalIF":4.3,"publicationDate":"2025-05-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12104242/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144149900","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Deletion of succinic semialdehyde dehydrogenase sad and chromosomal expression of phosphoenolpyruvate carboxylase as metabolic requirements for improved production of 2,4-dihydroxybutyric acid via malyl-P pathway using <i>E. coli</i>.","authors":"T A Stefanie Nguyen, Ceren Alkim, Nadine Ihle, Thomas Walther, Cláudio J R Frazão","doi":"10.3389/fbioe.2025.1589489","DOIUrl":"https://doi.org/10.3389/fbioe.2025.1589489","url":null,"abstract":"<p><p>The fermentative production of the functional precursor 2,4-dihydroxybutyrate (DHB) enables sustainable synthesis of the methionine analogue hydroxy-4-(methylthio) butyrate, which is currently still produced from fossil fuels. In this work, we aimed to optimize the aerobic production of DHB from glucose through the synthetic malyl phosphate (MalP) pathway, which comprises the conversion of the natural TCA cycle intermediate malate into MalP and the subsequent reactions to yield malate semialdehyde (MalSA) and finally DHB. We first implemented the synthetic pathway in an engineered <i>Escherichia coli</i> strain previously reported to over-produce malate through the oxidative TCA cycle. However, DHB was only detected in trace amounts, while acetate and malate were secreted in high quantities. Subsequent construction of strains producing malate, but negligible amounts of acetate, revealed that an increased supply of malate alone is not sufficient for improved production of DHB. Instead, we discovered metabolic inefficiencies in the DHB pathway as we found that deleting the endogenous succinate semialdehyde dehydrogenase Sad, whose natural substrate is structurally similar to MalSA, strongly improved performance of the DHB pathway. Specifically, with the single knock-out of <i>sad</i> we could achieve a 3-fold increase in DHB production with a yield of 0.15 mol mol^-1 compared to the wildtype host in shake flask experiments. With additional chromosomal expression of the mutant <i>ppc</i> _<i>K620S</i> gene encoding the malate-insensitive phosphoenolpyruvate carboxylase under control of a weak constitutive promoter, we achieved a DHB yield of 0.22 mol mol^-1, which corresponds to 17% of the maximal yield under aerobic conditions.</p>","PeriodicalId":12444,"journal":{"name":"Frontiers in Bioengineering and Biotechnology","volume":"13 ","pages":"1589489"},"PeriodicalIF":4.3,"publicationDate":"2025-05-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12104201/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144149848","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}