Microbial Cell Factories最新文献

{"title":"Uncoupling protein production from growth: different strategies for intracellular and secreted proteins in yeast.","authors":"Nuran Temelli, Willem H Baris, Ruud A Weusthuis, Markus M M Bisschops","doi":"10.1186/s12934-025-02848-0","DOIUrl":"10.1186/s12934-025-02848-0","url":null,"abstract":"<p><strong>Background: </strong>Precision fermentation offers a sustainable alternative production route for proteins but still suffers from moderate productivities and low yields. Especially compared to biomass yields, recombinant protein yields on substrate are very low. Uncoupling recombinant protein production from growth would allow higher product yields, but requires that productivity is maintained. So far, two-phase production processes mostly rely on inducers to activate recombinant protein production after an initial growth phase, e.g., a change in carbon source. On large scale, specific growth rates can be controlled by nutrient availability, and we aim to use this as trigger to uncouple recombinant protein production from growth.</p><p><strong>Results: </strong>We investigated the correlation between low specific growth rates (0.02 h^- 1 < µ < 0.1 h^- 1) and specific recombinant protein production rates, both for intracellularly accumulating and secreted proteins. By comparing two differently regulated promoters, the strong, constitutive P_TEF1 and stress-induced P_HSP12, we show that recombinant protein production rates and yields in Saccharomyces cerevisiae can be partially uncoupled from growth. The optimal strategy thereby differs for intracellular and secreted production. The P_HSP12 resulted in increased product yields of intracellular protein at very low growth rates, including a 10-fold increase in intracellular protein titer, while titers remained virtually constant for the benchmark P_TEF1. The P_TEF1 on the other hand led to increased protein secretion rates and efficiencies at lower specific growth rates cumulating in higher extracellular protein titers.</p><p><strong>Conclusion: </strong>Our results demonstrate that promoter selection plays a critical role in production performance under slow growing conditions. Moreover, it highlights that optimising intracellular and extracellular recombinant protein production requires distinct, strategy-specific approaches.</p>","PeriodicalId":18582,"journal":{"name":"Microbial Cell Factories","volume":"24 1","pages":"224"},"PeriodicalIF":4.9,"publicationDate":"2025-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12519851/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145286569","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":"Stress response regulation to extracellular polymeric substances biosynthesis in Bacillus licheniformis.","authors":"Xiaoyu Wei, Ziwei Pan, Zhen Chen, Ning He","doi":"10.1186/s12934-025-02846-2","DOIUrl":"10.1186/s12934-025-02846-2","url":null,"abstract":"<p><strong>Background: </strong>The diverse metabolic mechanisms underlying bacterial extracellular polymeric substances give rise to a wide array of components with distinct functionalities, including exopolysaccharides (EPS) and poly-γ-glutamic acid (γ-PGA). The coordinated synthesis of various types of extracellular polymeric substances necessitates comprehensive investigation from a global regulatory perspective.</p><p><strong>Results: </strong>In this study, we examined the impact of multiple environmental stressors on Bacillus species, revealing that the EPS and γ-PGA produced respond to stress through metabolic and cellular process reorganization. The overexpression of global transcriptional regulators influenced the production of EPS and γ-PGA differently. Specifically, quorum sensing-related global regulators such as rsbRA, rapA, and the carbon utilization regulator ccpA-2 were found to enhance EPS synthesis. Conversely, positive global transcriptional regulators associated with γ-PGA synthesis included carbon and nitrogen utilization-related regulators ccpA-2, cggR, and nrgB. Notably, the global regulators nrgB and cggR increased γ-PGA production by 33.64% and 44.14%, respectively, while this enhancement was accompanied by a concomitant reduction in EPS production. In B. licheniformis, omics analyses have elucidated critical pathways and metabolites implicated in stress response mechanisms that induce alterations in amino acid metabolism, carbon source utilization, alongside the activation of global regulatory elements. These studies indicated that nrgB predominantly governs downstream genes associated with carbon metabolism, energy metabolism, signal transduction, and membrane transport processes.</p><p><strong>Conclusions: </strong>This work combines stress induction strategies and global transcription machinery engineering for investigating the coordinated synthesis of various types of extracellular polymeric substances, which has not been explored before. The insights gained from our research contribute to a deeper understanding of the regulatory networks governing the competition between γ-PGA and EPS, thereby providing a theoretical basis for the engineered modification of Bacillus licheniformis aimed at optimizing the production of extracellular polymeric substances.</p>","PeriodicalId":18582,"journal":{"name":"Microbial Cell Factories","volume":"24 1","pages":"222"},"PeriodicalIF":4.9,"publicationDate":"2025-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12519863/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145286599","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":"Aokap9 gene knockout contributes to kojic acid synthesis in Aspergillus oryzae.","authors":"Ting Qiu, Huanxin Zhang, Yuzhen Li, Lihua Yao, Zhe Zhang","doi":"10.1186/s12934-025-02852-4","DOIUrl":"10.1186/s12934-025-02852-4","url":null,"abstract":"<p><strong>Background: </strong>Kojic acid, a significant secondary metabolite primarily synthesized by Aspergillus oryzae, has extensive applications across various industries. It is imperative to identify effective gene targets that can enhance kojic acid production and to elucidate its biosynthetic regulation for yield optimization in A. oryzae.</p><p><strong>Results: </strong>In this study, we identify the Aokap9 gene, which encodes an uncharacterized protein containing two transmembrane domains, as being closely associated with kojic acid synthesis. Disruption of Aokap9 resulted in increased kojic acid production, whereas mutations in either kojR or laeA within the ΔAokap9 background abolished synthesis, indicating that Aokap9 regulates kojic acid synthesis through kojR and laeA. Conversely, AozfA overexpression suppressed kojic acid accumulation in the ΔAokap9 strain. Furthermore, disruption of AozfA or overexpression of kojR in the Aokap9 mutant resulted in significantly elevated yields, unlike the effects observed with laeA overexpression. Transcriptome profiling further revealed that AoKap9 plays a role in the oxidative stress response through influencing the expression of superoxide dismutase, catalase, and copper amine oxidase in A. oryzae.</p><p><strong>Conclusion: </strong>AoKap9 mediates kojic acid synthesis through a regulatory pathway involving AoZFA, LaeA, and KojR, making it as an important gene target for enhancing kojic acid in A. oryzae. These findings provide essential insights into the regulatory mechanisms governing kojic acid biosynthesis and highlight Aokap9 as a promising target for metabolic engineering in A. oryzae.</p>","PeriodicalId":18582,"journal":{"name":"Microbial Cell Factories","volume":"24 1","pages":"221"},"PeriodicalIF":4.9,"publicationDate":"2025-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12519625/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145286520","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 and characterization of a novel β-galactosidase active at low temperatures from the Antarctic fungus Tetracladium sp., expressed in Saccharomyces cerevisiae.","authors":"Fernando Gutierrez, Jennifer Alcaino, Victor Cifuentes, Marcelo Baeza","doi":"10.1186/s12934-025-02850-6","DOIUrl":"10.1186/s12934-025-02850-6","url":null,"abstract":"<p><strong>Background: </strong>β-Galactosidases are widely used in the dairy industry to produce lactose-free milk and prebiotics such as galacto-oligosaccharides and lactulose. Since commercial β-galactosidases have optimal activity at 35 to 70 °C, β-galactosidases that are highly active at lower temperatures are desirable to reduce production costs and minimize microbial contamination in industrial processes. Potential sources of cold-active β-galactosidases are microorganisms living in cold environments such as Antarctica. The aim of this work was to identify genes encoding β-galactosidases from Antarctic fungi and express them in Saccharomyces cerevisiae for their characterization.</p><p><strong>Results: </strong>By searching 16 ORFeomes from eight Antarctic fungi, an ORF encoding β-galactosidase was identified in Tetracladium sp. (Tspgal), and the gene structure was determined in the corresponding genome. Phylogenetic analyses indicate that this is a novel β-galactosidase closely related to β-galactosidases from saprophytic fungi. The closest β-galactosidase with a known 3D structure was from Cellvibrio japonicus, which differed from that from Tetracladium sp. mainly in unstructured regions, with most of the active site residues conserved. The Tspgal expressed in S. cerevisiae showed maximum activity from 25 °C to 40 °C and from pH 5.5 to pH 7.0 (maximum at 35 °C and pH 6.0). At pH 6.0, the recombinant enzyme retained 25% and 36% of its activity at 10 °C and 50 °C, respectively. The thermal enzymatic inactivation of the recombinant β-galactosidase correlated with its thermal protein unfolding, a behavior similar to that observed for mesophilic enzymes. Tspbgal hydrolyzed lactose optimally at pH 5.0 at 35 °C, retaining about 80% of its activity at pH 6.0 and 7.0, conditions that coincide with the pH of whey, a major dairy byproduct and potential source of value‑added products derived from lactose.</p><p><strong>Conclusions: </strong>A novel β-galactosidase was identified in the ORFeome of the Antarctic fungus Tetracladium sp., which was successfully expressed in S. cerevisiae exhibiting structural and thermal stability properties comparable to mesophilic enzymes. The recombinant enzyme exhibited high activity at 25-35 °C and retained 25% of its maximum activity at 10 °C, an attractive trait for reducing energy costs and minimizing microbial contamination in milk treatments.</p>","PeriodicalId":18582,"journal":{"name":"Microbial Cell Factories","volume":"24 1","pages":"223"},"PeriodicalIF":4.9,"publicationDate":"2025-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12519765/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145286602","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":"Overexpression of Scr1 protein induces strong changes in the transcriptome and metabolome of Streptomyces coelicolor that affect antibiotic production.","authors":"Carolina Riascos, Gemma Fernández-García, Javier García-Martín, Ángel Manteca, Ramón I Santamaría, Margarita Díaz","doi":"10.1186/s12934-025-02843-5","DOIUrl":"10.1186/s12934-025-02843-5","url":null,"abstract":"<p><strong>Background: </strong>Xenobiotic response element (XRE) regulator proteins play an important role in gene regulation in Streptomyces. In these bacteria, they are often encoded together with a small protein containing a DUF397 domain. Previous work on 15 such pairs present in S. coelicolor has shown they act as pleiotropic regulators. They dependently affect antibiotic production and morphological differentiation on different culture media. Overexpression of the protein Scr1, which is encoded by gene SCO4441, induces a drastic increase in the production of the antibiotic actinorhodin in this bacterium. This study involves a transcriptomic and metabolomic study of this overexpression.</p><p><strong>Results: </strong>RNA-Seq assay showed that overexpression of Scr1 in the wild-type strain of S. coelicolor modified the expression of 1,308 genes at 36 h of culture incubation and 1339 at 48 h. The data indicated that almost 70% of the differentially expressed genes were up-regulated. Among them, 21% of the overexpressed genes were related to antibiotic biosynthesis pathways corresponding to antibiotics such as actinorhodin, calcium-dependent antibiotic (CDA), ectoin, arsono, hopene, coelimycin-P1, and albaflavenone. Conversely, some pathways were under-expressed such as those corresponding to coelichelin and undecylprodigiosin production. Metabolome studies corroborated these results and showed that the most notable differences in the production of these metabolites occurred at 72 and 96 h of incubation. A total of 3,978 and 4,392 metabolites were detected at 72 and 96 h respectively, from which 54 and 45 adducts corresponding to 15 and 14 secondary metabolites were identified. Of these, 5-hydroxyectoine, actinorhodin, albaflavenone, coelichelin, and coelimycin P1 are a few examples. In addition, other metabolic processes were affected such as those associated with energy metabolism, protein synthesis, response to stress, and the transport of molecules.</p><p><strong>Conclusions: </strong>The overexpression of Scr1 in S. coelicolor causes changes in the regulation of secondary metabolite biosynthesis that may be related to the alteration of several other important primary metabolites. This transcriptional and metabolomic analysis takes a step forward in elucidating the pleiotropic role of the Scr1 protein in developmental processes and its importance in the biosynthesis of secondary metabolites in S. coelicolor. A model of its regulatory network is presented.</p>","PeriodicalId":18582,"journal":{"name":"Microbial Cell Factories","volume":"24 1","pages":"218"},"PeriodicalIF":4.9,"publicationDate":"2025-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12516864/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145280706","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":"Solution towards low yield biosurfactant production from bacteria, a novel approach using microalgae-bacteria consortium.","authors":"Yan Jer Ng, Kuan Shiong Khoo, Kit Wayne Chew, Doris Ying Ying Tang, Sarah Alharthi, Andres Philip Mayol, Pau Loke Show","doi":"10.1186/s12934-025-02830-w","DOIUrl":"10.1186/s12934-025-02830-w","url":null,"abstract":"<p><strong>Background: </strong>Surfactants are an important chemical in the industry due to their unique properties to reduce surface tension between fluids. To date, raw materials involved for the synthesis of surfactants are mostly derived from petroleum-based compounds. Although the current petroleum reserve can sustain annual consumption, petroleum is a non-renewable resource thus a sustainable alternative is needed. Current research has been focusing on exploring alternative biological feedstock for biosurfactants derived from microbes. However, these biosurfactants are usually from bacteria having either low yield or from pathogenic bacteria. This research aims to assess the potential of Bacillus subtilis-Desmodesmus perforatus consortium to produce biosurfactants at a higher efficiency compared to pure bacteria.</p><p><strong>Results: </strong>Results showed that the co-cultivation of bacteria with microalgae increases the yield of biosurfactants from 0.0207 ± 0.0124 g/100mL to 0.4584 ± 0.0205 g/100mL. Subsequent parameters including microalgae species, volume of microalgae or bacteria inoculated, volume and concentration of culture medium were optimized to increase the final yield of biosurfactant to achieve a yield of 0.7109 ± 0.0215 g/100 mL, far higher than the yield of biosurfactants produced by pure bacteria culture, proving that microalgae-bacteria consortium provides a solution to increase the yield of biosurfactants from non-pathogenic bacteria.</p><p><strong>Conclusion: </strong>This study has proven the potential of using a microalgae-bacteria consortium to produce glycolipids at an industrial feasible rate, which can help in reducing the reliance of the commercial petroleum-based surfactants.</p>","PeriodicalId":18582,"journal":{"name":"Microbial Cell Factories","volume":"24 1","pages":"220"},"PeriodicalIF":4.9,"publicationDate":"2025-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12519745/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145286548","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":"Development and clinical application of a PCR-UV assay for detection of carbapenem resistant Acinetobacter baumannii in bloodstream infections.","authors":"Lin Yu, Jingzhi Zhang, Ze Liu, Chushi Guan, Siyi Liu, Yandong Zhang, Ziman Wu, Xiaodan Zheng, Xianling Zhou, Baoqing Sun","doi":"10.1186/s12934-025-02822-w","DOIUrl":"10.1186/s12934-025-02822-w","url":null,"abstract":"<p><strong>Objective: </strong>Bloodstream infections caused by carbapenem-resistant Acinetobacter baumannii (CRAB) are a significant public health problem, with high morbidity and mortality. Detection and identification of CRAB is essential for early diagnosis and treatment. Therefore, a rapid and economical method for the detection of CRAB-associated Bloodstream infections (BSIs) is urgently needed.</p><p><strong>Methods: </strong>A triple PCR-UV reaction system has been developed for the detection of the antibiotic resistance genes OXA23, OXA51 and AB-specific gene. Primer specificity, limit of detection (LOD), reproducibility, and accuracy of the assay were evaluated. The PCR products were directly analyzed using UV and ImageJ analysis, which provided a quickly interpretation of the results. Furthermore, the established assay was validated on clinical isolates and compared with blood culture and drug susceptibility testing.</p><p><strong>Results: </strong>The triple PCR-UV method established in this study demonstrated strong primer specificity and discriminated CRAB among 23 common clinical pathogens. The results of this PCR method were validated by electrophoresis and showed good accuracy and reproducibility, with a limit of detection (LOD) of 3.0 × 10^-1 ng/uL. Meanwhile, the optimal annealing temperature for the triple method has been optimized to 56.4 ℃. The result of PCR amplification could be judged by the result of the gray value of the tube to be tested / the gray value of the blank control of the same lot. The ratio > 1.3 is CRAB, the ratio between 1.1-1.3 is carbapenem-sensitive Acinetobacter baumannii (CSAB), the ratio < 1.1 is negative result. When applied to detect 30 patients with BSIs of AB, the results were consistent with clinical blood culture identification and drug susceptibility testing.</p><p><strong>Conclusion: </strong>The triple PCR-UV assay developed in this study is a UV-visual, rapid, and cost-effective method for the detection of Acinetobacter baumannii (AB) and identification of CRAB in bloodstream infections. The assay could be particularly useful in community settings where expensive molecular instrumentation is not readily available and could help in the diagnosis and management of CRAB infections in BSIs.</p>","PeriodicalId":18582,"journal":{"name":"Microbial Cell Factories","volume":"24 1","pages":"219"},"PeriodicalIF":4.9,"publicationDate":"2025-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12516897/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145280691","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":"Functional characterization of lactate metabolism and its key regulatory genes reveals lactate-mediated modulation of carbon and nitrogen metabolism in Phaeodactylum tricornutum.","authors":"Jiawen Duan, Yi Zhang, Chenhui Li, Yimeng Zheng, Yanhua Zeng, Xin Zhang, Xiaoni Cai, Hao Long, Wei Ren, Zhenyu Xie, Aiyou Huang","doi":"10.1186/s12934-025-02779-w","DOIUrl":"10.1186/s12934-025-02779-w","url":null,"abstract":"<p><strong>Background: </strong>The marine diatom Phaeodactylum tricornutum plays a crucial role in global carbon and nitrogen cycling. Previous work revealed that lactate regulates carbon and nitrogen metabolism of P. tricornutum through protein lactylation, significantly affecting growth characteristics, photosynthetic efficiency, biochemical composition, and expression of genes related to carbon and nitrogen metabolism. However, the functional roles of lactate metabolism genes and their regulatory mechanisms in carbon-nitrogen homeostasis remain unexplored. This study aimed to characterize key lactate metabolism and regulatory genes (ldhA, Glo1, Glo2, D-LCR, GlxI, and GPCR) and elucidate their influence on carbon and nitrogen metabolic modulation in P. tricornutum.</p><p><strong>Results: </strong>Overexpression (OE) and RNA silence (AS) of ldhA, Glo1, Glo2, D-LCR, GlxI, and GPCR revealed their roles in lactate metabolism and regulation. The overexpression of Glo2 and ldhA enhanced exogenous lactate utilization and total lipid accumulation under low nitrogen (LN) conditions. Additionally, the overexpression of Glo1 and D-LCR facilitated the utilization of exogenous lactate to cope with LN conditions. In contrast, the growth and L-lactate consumption rates of GlxI and GPCR overexpression strains were significantly lower than or not significantly different from those of the WT strain. The key enzyme involved in lactate metabolism, LDHA, was selected for further functional analysis. Western blot analysis suggested that ldhA overexpression promoted the lactylation of an approximately 40 kDa lactylated protein in P. tricornutum. ¹³C-labeling analysis demonstrated that ldhA overexpression in P. tricornutum accelerated lactate utilization and the processes of glycolysis, TCA cycle, CCM, and Calvin cycle. RNA-Seq analysis revealed that ldhA overexpression promoted cell division metabolism and lipid metabolism in P. tricornutum under LN conditions and glycerophospholipid metabolism under exogenous lactate addition conditions.</p><p><strong>Conclusion: </strong>Lactate metabolism and lactylation metabolic processes mediated by LDHA, GLO1, GLO2 and D-LCR are important mechanisms by which lactate affects the growth of P. tricornutum, rapidly regulates carbon and nitrogen metabolism processes, and promotes the accumulation of lipids under LN conditions.</p>","PeriodicalId":18582,"journal":{"name":"Microbial Cell Factories","volume":"24 1","pages":"216"},"PeriodicalIF":4.9,"publicationDate":"2025-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12512433/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145258504","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":"Effects of bioreactor inoculation method on secondary metabolite production and morphological characteristics of Streptomyces rimosus in microparticle-enhanced cultivation (MPEC).","authors":"Anna Ścigaczewska, Tomasz Boruta, Marcin Bizukojć","doi":"10.1186/s12934-025-02844-4","DOIUrl":"10.1186/s12934-025-02844-4","url":null,"abstract":"","PeriodicalId":18582,"journal":{"name":"Microbial Cell Factories","volume":"24 1","pages":"217"},"PeriodicalIF":4.9,"publicationDate":"2025-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12513026/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145258555","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 of triacetic acid lactone from oleic acid by engineering the yeast Candida viswanathii.","authors":"Saptarshi Ghosh, Alex Hutagalung, Yuqian Gao, Javier E Flores, Yichao Han, Joonhoon Kim, Meagan C Burnet, Young-Mo Kim, Alberto Rodriguez","doi":"10.1186/s12934-025-02841-7","DOIUrl":"10.1186/s12934-025-02841-7","url":null,"abstract":"<p><p>Triacetic acid lactone (TAL) is a promising platform chemical to produce valuable compounds. The development of engineered microbial hosts to efficiently produce TAL from lipid-containing waste streams could be a cost-effective, sustainable and environmentally friendly approach to meet the industrial demand. In this study, we engineered the yeast Candida viswanathii, possessing robust fatty acid conversion capabilities, to develop an alternative route for TAL production from fatty acids that aims to maximize conversion of the acetyl-CoA pool generated by β-oxidation in the peroxisome. To do so, we inactivated the carnitine acetyltransferase gene to block the transport of acetyl-CoA out of the peroxisome and overexpressed the enzymes methylmalonyl-CoA carboxyltransferase, 2-pyrone synthase and pyruvate carboxylase in the peroxisome to convert acetyl-CoA into TAL. We also performed an adaptive laboratory evolution experiment to obtain mutants with higher growth rate in medium with oleic acid and observed marked differences in central carbon metabolism and organic acid production pathways between the evolved and parental strains. These strains were further engineered by integrating additional copies of TAL biosynthetic genes while reducing competing reactions like ω-oxidation and Lipid biosynthesis, resulting in up to 50-fold increase in titers relative to the initial strain, reaching 280 mg/L. This study contributes to the development of bioprocesses that valorize fatty acids as microbial conversion substrates for the production of valuable compounds.</p>","PeriodicalId":18582,"journal":{"name":"Microbial Cell Factories","volume":"24 1","pages":"215"},"PeriodicalIF":4.9,"publicationDate":"2025-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12502205/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145239163","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}