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The copy number of genes in chromosomes can be modified by chromosomal integration to construct efficient microbial cell factories but the resulting genetic systems are prone to failure or instability from triggering homologous recombination in repetitive DNA sequences. Finding the optimal copy number of each gene in a pathway is also time and labor intensive. To overcome these challenges, we applied a multiple nonrepetitive coding sequence calculator that generates sets of coding DNA sequence (CDS) variants. A machine learning method was developed to calculate the optimal copy number combination of genes in a pathway. We obtained an engineered Yarrowia lipolytica strain for eicosapentaenoic acid biosynthesis in 6 months, producing the highest titer of 27.5 g l-1 in a 50-liter bioreactor. Moreover, the lycopene production in Escherichia coli was also greatly improved. Importantly, all engineered strains of Y. lipolytica, E. coli and Saccharomyces cerevisiae constructed with nonrepetitive CDSs maintained genetic stability.
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Gastrodin, a phenolic glycoside, is a prominent component of Gastrodia elata, which is renowned for its sedative, hypnotic, anticonvulsant, and neuroprotective activities. Engineering heterologous production of plant natural products in microbial host represents a safe, cost-effective, and scalable alternative to plant extraction. Here, we present the construction of an engineered Yarrowia lipolytica yeast that achieves a high-titer production of gastrodin. We systematically refactored the yeast genome by enhancing the flux of the shikimate pathway and optimizing the glucosyl transfer system. We introduced more than five dozen of genetic modifications onto the yeast genome, including enzyme screening, alleviation of rate-limiting steps, promoter selection, genomic integration site optimization, downregulation of competing pathways, and elimination of gastrodin degradation. Meanwhile, we developed a Copper-induced Antisense-Transcriptional Regulation (CATR) tool. The developed CATR toolkit achieved dynamic repression and activation of violacein synthesis through the addition of copper in Y. lipolytica. This strategy was further used to dynamically regulate the pyruvate kinase node to effectively redirect glycolytic flux towards the shikimate pathway while maintaining cell growth at proper rate. Taken together, these efforts resulted in 9477.1 mg/L of gastrodin in shaking flaks and 13.4 g/L of gastrodin with a yield of 0.149 g/g glucose in a 5-L bioreactor, highlighting the potential for large-scale and sustainable production of gastrodin from microbial fermentation.
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Cobre , Yarrowia , Ácido Chiquímico , Glucosídeos , Álcoois Benzílicos , Yarrowia/genéticaRESUMO
The design of efficient catalysts for catalytic ethylene (C2H4) oxidation is of crucial importance for extending the shelf life of fruits and vegetables. Herein, a carbon modified SBA-15 supported Pt catalyst (Pt/CSBA-15) was prepared in situ by a facile solid phase grinding-infiltration-inert atmosphere calcination method. Characterization results reveal that in the Pt/CSBA-15 catalysts thin carbon layers are successfully formed in the hexagonal pores of SBA-15. Additionally, Pt particles are well dispersed in the channels of SBA-15, and Pt/CSBA-15 has a smaller Pt particle size than the catalyst without carbon modification (i.e., Pt/SBA-15). O2 is more feasibly adsorbed and activated on small-sized Pt particles, and in situ formed carbon species enhance the hydrophobicity of catalysts. As a result, both 3Pt/CSBA-15 and 5Pt/CSBA-15 are able to maintain 100% conversion of 50 ppm of C2H4 for more than 7 h at 0 °C. 3Pt/CSBA-15 even achieves 81.5% C2H4 conversion and 71.6% CO2 yield after 20 h, exhibiting much more prominent catalytic performances than 3Pt/SBA-15. DFT calculations and in situ FTIR measurements confirm that small-sized Pt particles possess strong O2 affinity to promote O2 adsorption, and in situ formed hydrophobic carbon layers efficiently suppress competitive H2O adsorption. Such a unique one-step catalyst preparation method for regulating the size of metal particles and the hydrophobicity of catalysts can be perfectly utilized to develop simple and efficient hydrophobic catalysts applied in low-temperature oxidation of C2H4.
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Considering that heavy-metal contamination of seawater is getting worse, building a quick, accurate and portable device for detecting trace zinc in seawater in real time would be very beneficial. In this work, a microfluidic system was developed that includes a planar disc electrode, a micro-cavity for detection, an electrochemical workstation, a computer, a container for waste liquid reprocessing, an external pipeline and other components as well as a graphene/cerium oxide/nano-cerium oxide/Nafion composite membrane was used to modify the planar disc electrode (GR/CeO2/Nafion/Au) to investigate the electrochemical behaviour of Zn(II) using cyclic voltammetry, square-wave voltammetry and orthogonal test methods. Under optimal experimental conditions, the peak reaction current of Zn(II) showed a good linear relationship with the concentration of Zn(II) in the range of 1-900 µg/L with a correlation coefficient of 0.998, and the detection limit of the method was 0.87 µg/L. In addition, the microfluidic system had good stability, reproducibility and anti-interference. The system was used for determining zinc ions in real seawater samples, and the results were very similar to those of inductively coupled plasma-emission spectrometry, demonstrating the practicality of the system for the detection of trace zinc.
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PURPOSE: The potential of uniportal video-assisted thoracic surgery (U-VATS) to reduce chronic pain after thoracic surgery (CPTS) compared to open thoracotomy (OT) remains unexplored. This prospective study aims to assess the incidence of CPTS following U-VATS or OT and identify associated risk factors. METHODS: Patients undergoing thoracic surgery were recruited from March 2021 to March 2022, categorized by surgical approach (U-VATS vs. OT). Standard clinical protocols for surgery, anesthesia, and analgesia were followed. Pain symptoms were assessed using the Short-form McGill Pain Questionnaire, with follow-ups up to 6 months. Perioperative factors influencing CPTS at 3 months were analyzed through univariate and multivariate methods. RESULTS: A total of 694 patients were analyzed. Acute pain after thoracic surgery (APTS) was significantly less severe in the U-VATS group (p < 0.001). U-VATS patients exhibited a lower incidence of CPTS at 3 months (63.4% vs. 80.1%, p < 0.001), with reduced severity among those experiencing CPTS (p = 0.007) and a decreased occurrence of neuropathic pain (p = 0.014). Multivariate analysis identified OT incision, moderate to severe APTS (excluding moderate static pain at 24 h postoperative), nocturnal surgery, and lung surgery as risk factors for CPTS. CONCLUSION: This study underscores the potential of U-VATS to reduce both the incidence and severity of CPTS at 3 months compared to OT. Furthermore, it highlights risk factors for CPTS, including OT incision, inadequately managed APTS, lung surgery, and nocturnal surgery. These findings emphasize the importance of considering surgical approach and perioperative pain management strategies to mitigate the burden of CPTS.
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Dor Crônica , Dor Pós-Operatória , Cirurgia Torácica Vídeoassistida , Toracotomia , Humanos , Cirurgia Torácica Vídeoassistida/métodos , Cirurgia Torácica Vídeoassistida/efeitos adversos , Masculino , Feminino , Estudos Prospectivos , Toracotomia/métodos , Toracotomia/efeitos adversos , Dor Crônica/epidemiologia , Dor Crônica/etiologia , Dor Pós-Operatória/epidemiologia , Dor Pós-Operatória/prevenção & controle , Pessoa de Meia-Idade , Idoso , Medição da Dor/métodos , Fatores de Risco , Adulto , Estudos de Coortes , IncidênciaRESUMO
Objective: The government has recently implemented reforms aimed at delegating power, streamlining administration, and optimizing government services. This reform has eliminated barriers that impede the growth of various industries, thereby unleashing innovative potential. Additionally, there have been several medical policies, including changes to medical insurance and centralized volume-based procurement. China's pharmaceutical market has undergone significant changes, leading to increased demands for innovation technology efficiency in pharmaceutical manufacturing. Methods: The three-stage BCC theory was employed to assess the effectiveness of technology innovation in the industry under this reform. Calculate precise comprehensive technical efficiency values, pure technical efficiency values, and scale efficiency values for technological innovation in the pharmaceutical industry across 30 provinces from 2018 to 2020, after removing environmental factors. Results: In 2020, Jiangsu and Shandong and nine other provinces reached the comprehensive technical efficiency frontier surface, joining Tianjin, Zhejiang, and Guangdong provinces. However, Gansu, Qinghai, Ningxia, and Xinjiang still need to catch up due to their smaller industrial scale and lack of technology. Discussion: To ensure the effectiveness of reforms, it is crucial to fully consider provincial differences. Articulating national and provincial policies is necessary to allow efficient provinces to continue and allocate resources toward less efficient provinces to improve overall efficiency.
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Invenções , Indústria Manufatureira , Preparações Farmacêuticas , Indústria Farmacêutica , Tecnologia , Governo , ChinaRESUMO
This comprehensive review delves into the significance of androgens in cervical cancer, examining both epidemiological evidence and the underlying biological mechanisms. Cervical cancer ranks as the fourth most prevalent cancer among women globally, with disproportionately higher incidence and mortality rates in less developed regions where cervical human papillomavirus (HPV) screening remains limited. Recent research highlights the previously underexplored role of androgens in cervical cancer. Notably, cervical tissues house androgen receptors, and elevated levels of endogenous androgens have been linked to an increased risk of cervical cancer. Androgens exert their influence on the development and progression of cervical cancer by impacting key cellular processes, including proliferation, apoptosis, differentiation, and epithelial cell transformation. Furthermore, specific HPV subtypes may interact with androgens, potentially modulating HPV-related cellular degeneration and transformation. In light of these findings, it is evident that androgens assume a crucial role in cervical cancer's pathogenesis. Consequently, further investigations are warranted to deepen our understanding of the intricate relationship between androgens and cervical cancer. Such knowledge advancements can facilitate improved strategies for early prevention and treatment of cervical cancer, especially in regions with limited HPV screening access. This review underscores the importance of considering androgens as a vital component of the multifaceted landscape of cervical cancer etiology and progression, ultimately contributing to more effective clinical interventions.
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As an emerging form of pollution, microplastic contamination of the coastal ecosystems is one of the world's most pressing environmental concerns. Coastal sediments have been polluted to varying degrees by microplastics, and their ubiquitous presence in sediments poses a threat to marine organisms. However, there is currently no ecological risk assessment of microplastics on aquatic biota in sediments. This study, for the first time, established a new procedure to evaluate the toxicity of microplastics on aquatic biota in sediments, based on the probabilistic risk assessment (PRA) concept. The choice of Zhelin Bay as the case study site was based on its severe pollution status. The average content of microplastics in the sediments of Zhelin Bay was 2054.17 items kg-1 dry weight, and these microplastics consisted of 46 different species. Microplastics in sediments exist in five different forms, with the film form being the main composition, and the majority of microplastics have particle sizes ranging from 100 to 500 µm. Correlation analysis (CA) reveals significant negative correlations between microplastic abundance, and Al2O3 and SiO2. The toxicity of microplastics, based on the PRA concept, suggests that Zhelin Bay surface sediments had a low probability (3.43%) of toxic effects on aquatic biota.
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Microplásticos , Poluentes Químicos da Água , Plásticos , Ecossistema , Dióxido de Silício , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/análise , Biota , Medição de Risco , Sedimentos GeológicosRESUMO
The paper reports a series of experimental and numerical data of destructive stub column tests on additively manufactured steel parts stiffened by surface sinusoidal wave patterns. The specimens were made in 316L stainless steel and manufactured by selective laser melting (SLM). The experimental tests covered five tensile coupon tests, fourteen square hollow section (SHS) stub column tests and measurements of geometric imperfections of the stub columns. Numerical models incorporating the measured material and geometric properties were developed and analysed via GMNIA approach. The validity of the numerical models is demonstrated by their accurate replications of the load-end shortening responses of the tested specimens. The reported dataset will contribute to the stability design and characterisation of thin-walled steel plated structures with advanced stiffening patterns.
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OBJECTIVES: Moderate-to-severe sleep-disordered breathing (SDB) is prevalent in patients with acute ischaemic stroke (AIS) and is associated with an increased risk of unfavourable prognosis. We aimed to develop and validate a reliable scoring system for the early screening of moderate-to-severe SDB in patients with AIS, with the objective of improving the management of those patients at risk. STUDY DESIGN: We developed and validated a nomogram model based on univariate and multivariate logistic analyses to identify moderate-to-severe SDB in AIS patients. Moderate-to-severe SDB was defined as an apnoea-hypopnoea index (AHI) ≥15. To evaluate the effectiveness of our nomogram, we conducted a comparison with the STOP-Bang questionnaire by analysing the area under the receiver operating characteristic curve. SETTING: Large stroke centre in northern Shanghai serving over 4000 inpatients, 100 000 outpatients and emergency visits annually. PARTICIPANTS: We consecutively enrolled 116 patients with AIS from the Shanghai Tenth People's Hospital. RESULTS: Five variables were independently associated with moderate-to-severe SDB in AIS patients: National Institutes of Health Stroke Scale score (OR=1.20; 95% CI 0.98 to 1.47), neck circumference (OR=1.50; 95% CI 1.16 to 1.95), presence of wake-up stroke (OR=21.91; 95% CI 3.08 to 156.05), neuron-specific enolase level (OR=1.27; 95% CI 1.05 to 1.53) and presence of brainstem infarction (OR=4.21; 95% CI 1.23 to 14.40). We developed a nomogram model comprising these five variables. The C-index was 0.872, indicated an optimal agreement between the observed and predicted SDB patients. CONCLUSIONS: Our nomogram offers a practical approach for early detection of moderate-to-severe SDB in AIS patients. This tool enables individualised assessment and management, potentially leading to favourable outcomes.
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Isquemia Encefálica , AVC Isquêmico , Síndromes da Apneia do Sono , Acidente Vascular Cerebral , Humanos , Isquemia Encefálica/complicações , Acidente Vascular Cerebral/complicações , Estudos Retrospectivos , Nomogramas , China , Síndromes da Apneia do Sono/complicações , AVC Isquêmico/complicaçõesRESUMO
BACKGROUND: Previous studies had indicated that sarcopenia and depressive symptoms were associated with increased risk of cardiovascular disease (CVD). The aim of present study was to evaluate the combined effect of sarcopenia and depressive symptoms on the CVD risk. METHODS: A total of 11,011 participants from the China Health and Retirement Longitudinal Study 2011-2020 were included. Multivariate Cox proportional hazards regression model was used to explore the associations between sarcopenia, depressive symptoms and new-onset CVD, stroke and cardiac events. RESULTS: During the 7-year follow-up, a total of 2,388 respondents experienced CVD (including 812 stroke and 1,831 cardiac events). There is a significant additive and multiplicative interactions of sarcopenia and depressive symptoms on risk of CVD, stroke and cardiac events. Compared with those without sarcopenia and depressive symptoms, individuals with depressive sarcopenia had the highest risk of CVD, stroke and cardiac events, with the corresponding hazard ratios (95% confidence interval) were 1.43 (1.26-1.63), 1.45 (1.15-1.82) and 1.50 (1.29-1.74), respectively. CONCLUSION: Our study indicated that there was a combined effect of sarcopenia and depressive symptoms on the risk of CVD, stroke and cardiac events. Our findings highlighted the importance of identifying sarcopenia and depressive symptoms, and intervening much earlier both in older and younger population.
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Doenças Cardiovasculares , Depressão , Sarcopenia , Humanos , Sarcopenia/epidemiologia , Sarcopenia/complicações , Depressão/epidemiologia , Masculino , Feminino , Doenças Cardiovasculares/epidemiologia , China/epidemiologia , Pessoa de Meia-Idade , Idoso , Estudos Longitudinais , Fatores de Risco , Modelos de Riscos Proporcionais , Acidente Vascular Cerebral/epidemiologia , População do Leste AsiáticoRESUMO
ITA and Beast methods were used to quantitatively analyze the nonlinear process of a PM2.5 concentration time series based on the PM2.5 concentration data of the three major urban agglomerations in China. The results showed thatï¼ â the degree of the PM2.5 pollution in the three major urban agglomerations had decreasedï¼ and the high-concentration areas had noticeably shrunk. The degree of spatial polarization of PM2.5 concentration was reducedï¼ and the spatial difference was narrowed. The PM2.5 concentration in most areas showed downward trendsï¼ but the degree of change was not the same. Compared with the YRD and PRDï¼ the concentration of PM2.5 in the BTH was still at a relatively high level. â¡ The concentration of PM2.5 in the three major urban agglomerations had seasonal variation characteristics that were high in winter and spring and low in summer and autumn. There were obvious differences in PM2.5 concentration between winter and summerï¼ and the convergence of PM2.5 concentration in summer was greater than that in winter. Areas with high PM2.5 concentration also had obvious downward trendsï¼ but the downward trends of PM2.5 concentration in the PRD were not obvious compared with those in the YRD and BTH. ⢠The PM2.5 concentration time series of the three major urban agglomerations all had significant downward trendsï¼ Beijing-Tianjin-Hebei ï¼BTHï¼ > the Yangtze River Delta ï¼YRDï¼ > the Pearl River Delta ï¼PRDï¼. The PM2.5 concentration had the largest downward trends in winter. The higher the PM2.5 pollution levelï¼ the greater the downward trends. ⣠The trend component of the PM2.5 concentration time series in the BTH had two change pointsï¼ and there was one change point in the seasonal component. The trend and seasonal components of the PM2.5 concentration time series in the YRD had no change point. There was no change point in the seasonal component but one change point in the trend component of the PM2.5 concentration time series in the PRD. These results can provide scientific references for regional air pollution control.
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Objectives: To look into the connection between amyotrophic lateral sclerosis (ALS) and atrial fibrillation (AF) using Mendelian randomization (MR). Methods: Two-sample MR was performed using genetic information from genome-wide association studies (GWAS). Genetic variants robustly associated with ALS and AF were used as instrumental variables. GWAS genetic data for ALS (n = 138,086, ncase = 27,205) and AF (n = 1,030,836, ncase = 60,620), publicly available from IEU Open. The specific MR protocols were Inverse variance-weighted (IVW), Simple mode, MR Egger, Weighted mode, and Weight median estimator (WME). Subsequently, the MR-Egger intercept and Cochran Q examine were used to evaluate instrumental variables (IVs)' heterogeneity and multiplicative effects (IVs). In addition, MR-PRESSO analysis was conducted to exclude any potential pleiotropy. Results: The IVW method demonstrated that ALS positively affected AF [OR: 1.062, 95% CI (1.004-1.122); P = 0.035]. Indeed, other MR methods were in accordance with the tendency of the IVW method (all OR > 1), and sensitivity testing verified the reliability of this MR result. Conclusions: This MR study proves a positive causal connection between ALS and atrial fibrillation. Further studies are warranted to elucidate the mechanisms linking ALS and AF.
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Background and objective: Aberrant epigenetic regulation and increased oxidative stress in the placenta play a significant role in placental pathophysiology and fetal programming in preeclampsia, a hypertensive disorder in human pregnancy. The purpose of the study is to investigate if hypermethylation of histone H3K9 occurs in placental trophoblasts from preeclampsia. Methods: Trophoblasts were isolated and cultured from 14 placentas, 7 from normotensive pregnant women and 7 from preeclamptic pregnancies. Methylated H3K9 expression and antioxidant superoxide dismutase expression were determined by Western blot. We also examined consequences of oxidative stress and the downstream effects of histone methyltransferase inhibition on H3K9 expression associated with antioxidant CuZn-SOD and Mn-SOD expression in placental trophoblasts. Results: We found that expression of mono-, di-, and tri-methylation of histone H3 lysine 9 (H3K9me1, H3K9me2 and H3K9me3) was significantly increased, p<0.01, which correlated with downregulation of antioxidant superoxide dismutase CuZn-SOD and Mn-SOD expression, in trophoblasts from preeclamptic placentas compared to those from uncomplicated control placentas. We further demonstrated hypoxia could promote histone H3K9 methylation in placental trophoblasts, and hypoxia-induced upregulation of H3K9me1, H3K9me2 and H3K9me3 expression was reversible when hypoxic condition was removed. In addition, we also uncovered that inhibition of methyltransferase not only prevented hypoxia-induced upregulation of H3K9me1, H3K9me2 and H3K9me3 expression, but also abolished hypoxia-induced downregulation of CuZn-SOD and Mn-SOD expression in placental trophoblasts. Conclusions: These findings are noteworthy and provide further evidence that increased oxidative stress in the intrauterine environment is likely a mechanism to induce aberrant histone modification in placental trophoblasts in preeclampsia. Moreover, CuZn-SOD and Mn-SOD expression/activity are possibly H3K9 methylation-dependent in placental trophoblasts, which further suggest that oxidative stress and aberrant histone modification have significant impact on placental trophoblasts/fetal programming in preeclampsia.
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Histonas , Estresse Oxidativo , Placenta , Pré-Eclâmpsia , Trofoblastos , Humanos , Feminino , Pré-Eclâmpsia/metabolismo , Pré-Eclâmpsia/genética , Pré-Eclâmpsia/patologia , Gravidez , Trofoblastos/metabolismo , Histonas/metabolismo , Adulto , Placenta/metabolismo , Metilação , Superóxido Dismutase/metabolismo , Superóxido Dismutase/genética , Metilação de DNA , Células Cultivadas , Lisina/metabolismoRESUMO
INTRODUCTION: Lung adenocarcinoma (LUAD) is a common pathological type of lung cancer. The presence of lymph node metastasis plays a crucial role in determining the overall treatment approach and long-term prognosis for early LUAD, therefore accurate prediction of lymph node metastasis is essential to guide treatment decisions and ultimately improve patient outcomes. METHODS: We performed transcriptome sequencing on T1 LUAD patients with positive or negative lymph node metastases and combined this data with The Cancer Genome Atlas Program cohort to identify potential risk molecules at the tissue level. Subsequently, by detecting the expression of these risk molecules by real-time quantitative PCR in serum samples, we developed a model to predict the risk of lymph node metastasis from a training cohort of 96 patients and a validation cohort of 158 patients. RESULTS: Through transcriptome sequencing analysis of tissue samples, we identified 11 RNA (miR-412, miR-219, miR-371, FOXC1, ID1, MMP13, COL11A1, PODXL2, CXCL13, SPOCK1 and MECOM) associated with positive lymph node metastases in T1 LUAD. As the expression of FOXC1 and COL11A1 was not detected in serum, we constructed a predictive model that accurately identifies patients with positive lymph node metastases using the remaining nine RNA molecules in the serum of T1 LUAD patients. In the training set, the model achieved an area under the curve (AUC) of 0.89, and in the validation set, the AUC was 0.91. CONCLUSIONS: We have established a new risk prediction model using serum samples from T1 LUAD patients, enabling noninvasive identification of those with positive lymph node metastases.
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Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Metástase Linfática , Humanos , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/patologia , Feminino , Masculino , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/genética , Biópsia Líquida/métodos , Pessoa de Meia-Idade , Idoso , Biomarcadores Tumorais/genética , PrognósticoRESUMO
The utilization of industrial biomanufacturing has emerged as a viable and sustainable alternative to fossil-based resources for producing functional chemicals. Moreover, advancements in synthetic biology have created new opportunities for the development of innovative cell factories. Notably, Yarrowia lipolytica, an oleaginous yeast that is generally regarded as safe, possesses several advantageous characteristics, including the ability to utilize inexpensive renewable carbon sources, well-established genetic backgrounds, and mature genetic manipulation methods. Consequently, there is increasing interest in manipulating the metabolism of this yeast to enhance its potential as a biomanufacturing platform. Here, we reviewed the latest developments in genetic expression strategies and manipulation tools related to Y. lipolytica, particularly focusing on gene expression, chromosomal operation, CRISPR-based tool, and dynamic biosensors. The purpose of this review is to serve as a valuable reference for those interested in the development of a Y. lipolytica microbial factory.
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In this paper, the deformation behavior of UNS S32750 (S32750) duplex stainless steel during low cycle fatigue was studied by controlling the number of cycles. The microstructure of the specimens under different cycles was characterized by optical microscope (OM), scanning electron microscope (SEM), electron backscatter diffraction (EBSD), and transmission electron microscope (TEM). The microhardness of the two phases was measured by a digital microhardness instrument. The results showed that the microhardness of ferrite increases significantly after the first 4000 cycles, while the austenite shows a higher strain hardening rate after fatigue fracture, and the microhardness of ferrite and austenite increases by 23 HV and 87 HV, respectively. The two-phase kernel average misorientation (KAM) diagram showed that the continuous accumulation of plastic deformation easily leads to the initiation of cracks inside the austenite and at the phase boundaries. The evolution of dislocation morphology in the two phases was obviously different. With the increase in cycle number, the dislocation in ferrite gradually transforms from dislocation bundles and a dislocation array to a sub-grain structure, while the dislocation in austenite gradually develops from dipole array to an ordered Taylor lattice network structure.
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Flavonoids, a significant group of natural polyphenolic compounds, possess a broad spectrum of pharmacological effects. Recent advances in the systematic metabolic engineering of yeast cell factories (YCFs) provide new opportunities for enhanced flavonoid production. Herein, we outline the latest research progress on typical flavonoid products in YCFs. Advanced engineering strategies involved in flavonoid biosynthesis are discussed in detail, including enhancing precursor supply, cofactor engineering, optimizing core pathways, eliminating competitive pathways, relieving transport limitations, and dynamic regulation. Additionally, we highlight the existing problems in the biosynthesis of flavonoid glucosides in yeast, such as endogenous degradation of flavonoid glycosides, substrate promiscuity of UDP-glycosyltransferases, and an insufficient supply of UDP-sugars, with summaries on the corresponding solutions. Discussions also cover other typical postmodifications like prenylation and methylation, and the recent biosynthesis of complex flavonoid compounds in yeast. Finally, a series of advanced technologies are envisioned, i.e., semirational enzyme engineering, ML/DL algorithn, and systems biology, with the aspiration of achieving large-scale industrial production of flavonoid compounds in the future.