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1.
BMC Microbiol ; 24(1): 238, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38961393

RESUMO

OBJECTIVES: Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) is extensively employed for the identification of filamentous fungi on MALDI Biotyper (Bruker Daltonics) and Vitek MS (biomerieux), but the performance of fungi identification on new EXS2600 (Zybio) is still unknow. Our study aims to evaluate the new EXS2600 system's (Zybio) ability to rapidly identify filamentous fungi and determine its effect on turnaround time (TAT) in our laboratory. METHODS: We tested 117 filamentous fungi using two pretreatment methods: the formic acid sandwich (FA-sandwich) and a commercial mold extraction kit (MEK, Zybio). All isolates were confirmed via sequence analysis. Laboratory data were extracted from our laboratory information system over two 9-month periods: pre-EXS (April to December 2022) and post-EXS (April to December 2023), respectively. RESULTS: The total correct identification (at the species, genus, or complex/group level) rate of fungi was high, FA-sandwich (95.73%, 112/117), followed by MEK (94.02%, 110/117). Excluding 6 isolates not in the database, species-level identification accuracy was 92.79% (103/111) for FA-sandwich and 91.89% (102/111) for MEK; genus-level accuracy was 97.29% (108/111) and 96.39% (107/111), respectively. Both methods attained a 100% correct identification rate for Aspergillus, Lichtheimia, Rhizopus Mucor and Talaromyces species, and were able to differentiate between Fusarium verticillioides and Fusarium proliferatum within the Fusarium fujikuroi species complex. Notably, high confidence was observed in the species-level identification of uncommon fungi such as Trichothecium roseum and Geotrichum candidum. The TAT for all positive cultures decreased from pre EXS2600 to post (108.379 VS 102.438, P < 0.05), and the TAT for tissue decreased most (451.538 VS 222.304, P < 0.001). CONCLUSIONS: The FA-sandwich method is more efficient and accurate for identifying filamentous fungi with EXS2600 than the MEK. Our study firstly evaluated the performance of fungi identification on EXS2600 and showed it is suitable for clinical microbiology laboratories use.


Assuntos
Formiatos , Fungos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Fungos/classificação , Fungos/isolamento & purificação , Fungos/química , Fungos/genética , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Formiatos/química
2.
Molecules ; 29(11)2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38893534

RESUMO

Electrocatalytic CO2 reduction to CO and formate can be coupled to gas fermentation with anaerobic microorganisms. In combination with a competing hydrogen evolution reaction in the cathode in aqueous medium, the in situ, electrocatalytic produced syngas components can be converted by an acetogenic bacterium, such as Clostridium ragsdalei, into acetate, ethanol, and 2,3-butanediol. In order to study the simultaneous conversion of CO, CO2, and formate together with H2 with C. ragsdalei, fed-batch processes were conducted with continuous gassing using a fully controlled stirred tank bioreactor. Formate was added continuously, and various initial CO partial pressures (pCO0) were applied. C. ragsdalei utilized CO as the favored substrate for growth and product formation, but below a partial pressure of 30 mbar CO in the bioreactor, a simultaneous CO2/H2 conversion was observed. Formate supplementation enabled 20-50% higher growth rates independent of the partial pressure of CO and improved the acetate and 2,3-butanediol production. Finally, the reaction conditions were identified, allowing the parallel CO, CO2, formate, and H2 consumption with C. ragsdalei at a limiting CO partial pressure below 30 mbar, pH 5.5, n = 1200 min-1, and T = 32 °C. Thus, improved carbon and electron conversion is possible to establish efficient and sustainable processes with acetogenic bacteria, as shown in the example of C. ragsdalei.


Assuntos
Reatores Biológicos , Butileno Glicóis , Dióxido de Carbono , Monóxido de Carbono , Clostridium , Fermentação , Formiatos , Hidrogênio , Formiatos/metabolismo , Formiatos/química , Clostridium/metabolismo , Clostridium/crescimento & desenvolvimento , Monóxido de Carbono/metabolismo , Hidrogênio/metabolismo , Dióxido de Carbono/metabolismo , Butileno Glicóis/metabolismo , Butileno Glicóis/química , Gases/metabolismo , Gases/química , Etanol/metabolismo
3.
Nat Commun ; 15(1): 5424, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38926344

RESUMO

Anaerobic, acetogenic bacteria are well known for their ability to convert various one-carbon compounds, promising feedstocks for a future, sustainable biotechnology, to products such as acetate and biofuels. The model acetogen Acetobacterium woodii can grow on CO2, formate or methanol, but not on carbon monoxide, an important industrial waste product. Since hydrogenases are targets of CO inhibition, here, we genetically delete the two [FeFe] hydrogenases HydA2 and HydBA in A. woodii. We show that the ∆hydBA/hydA2 mutant indeed grows on CO and produces acetate, but only after a long adaptation period. SNP analyzes of CO-adapted cells reveal a mutation in the HycB2 subunit of the HydA2/HydB2/HydB3/Fdh-containing hydrogen-dependent CO2 reductase (HDCR). We observe an increase in ferredoxin-dependent CO2 reduction and vice versa by the HDCR in the absence of the HydA2 module and speculate that this is caused by the mutation in HycB2. In addition, the CO-adapted ∆hydBA/hydA2 mutant growing on formate has a final biomass twice of that of the wild type.


Assuntos
Acetobacterium , Proteínas de Bactérias , Monóxido de Carbono , Formiatos , Acetobacterium/genética , Acetobacterium/metabolismo , Acetobacterium/crescimento & desenvolvimento , Formiatos/metabolismo , Monóxido de Carbono/metabolismo , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Hidrogenase/metabolismo , Hidrogenase/genética , Mutação , Dióxido de Carbono/metabolismo , Transporte de Elétrons , Biomassa , Acetatos/metabolismo , Polimorfismo de Nucleotídeo Único
4.
J Colloid Interface Sci ; 672: 97-106, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-38833738

RESUMO

Formate is an important environmental pollutant, and meanwhile its concentration change is associated with a variety of diseases. Thus, rapid and sensitive detection of formate is critical for the biochemical analysis of complex samples and clinical diagnosis of multiple diseases. Herein, a colorimetric biosensor was constructed based on the cascade catalysis of formate oxidase (FOx) and horseradish peroxidase (HRP). These two enzymes were co-immobilized in Cu3(PO4)2-based hybrid nanoflower with spatial localization, in which FOx and HRP were located in the shell and core of nanoflower, respectively (FOx@HRP). In this system, FOx could catalyze the oxidation of formate to generate H2O2, which was then utilized by HRP to oxidize 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid to yield blue product. Ideal linear correlation could be obtained between the absorbance at 420 nm and formate concentration. Meanwhile, FOx@HRP exhibited excellent detection performance with low limit of detection (6 µM), wide linear detection range (10-900 µM), and favorable specificity, stability and reusability. Moreover, it could be applied in the detection of formate in environmental, food and biological samples with high accuracy. Collectively, FOx@HRP provides a useful strategy for the simple and sensitive detection of formate and is potentially to be used in biochemical analysis and clinical diagnosis.


Assuntos
Colorimetria , Enzimas Imobilizadas , Formiatos , Peroxidase do Rábano Silvestre , Colorimetria/métodos , Formiatos/química , Peroxidase do Rábano Silvestre/química , Peroxidase do Rábano Silvestre/metabolismo , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Técnicas Biossensoriais/métodos , Limite de Detecção , Nanoestruturas/química , Tamanho da Partícula , Propriedades de Superfície
5.
Biotechnol J ; 19(6): e2400290, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38900053

RESUMO

Synthetic biology is contributing to the advancement of the global net-negative carbon economy, with emphasis on formate as a member of the one-carbon substrate garnering substantial attention. In this study, we employed base editing tools to facilitate adaptive evolution, achieving a formate tolerance of Yarrowia lipolytica to 1 M within 2 months. This effort resulted in two mutant strains, designated as M25-70 and M25-14, both exhibiting significantly enhanced formate utilization capabilities. Transcriptomic analysis revealed the upregulation of nine endogenous genes encoding formate dehydrogenases when cultivated utilizing formate as the sole carbon source. Furthermore, we uncovered the pivotal role of the glyoxylate and threonine-based serine pathway in enhancing glycine supply to promote formate assimilation. The full potential of Y. lipolytica to tolerate and utilize formate establishing the foundation for pyruvate carboxylase-based carbon sequestration pathways. Importantly, this study highlights the existence of a natural formate metabolic pathway in Y. lipolytica.


Assuntos
Formiatos , Yarrowia , Yarrowia/genética , Yarrowia/metabolismo , Formiatos/metabolismo , Engenharia Metabólica/métodos , Redes e Vias Metabólicas/genética , Formiato Desidrogenases/genética , Formiato Desidrogenases/metabolismo , Evolução Molecular Direcionada , Glioxilatos/metabolismo , Edição de Genes
6.
STAR Protoc ; 5(2): 103093, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38796846

RESUMO

Formic acid is a viable product of CO2 utilization. Here, we present a protocol for designing and operating a pilot-scale formic acid production plant with a 10 kg/day capacity produced via CO2 hydrogenation. We describe the essential process specifications required for successful operation, including prevention of corrosion and formic acid decomposition. We then detail procedures for steady-state operation of the individual units. This protocol provides the necessary information for further scale-up and commercialization of the CO2 hydrogenation process. For complete details on the use and execution of this protocol, please refer to Kim et al.1.


Assuntos
Dióxido de Carbono , Formiatos , Formiatos/química , Dióxido de Carbono/química , Hidrogenação
7.
J Inorg Biochem ; 257: 112594, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38749080

RESUMO

We have characterized the catalytic cycle of the Helicobacter pylori KatA catalase (HPC). H. pylori is a human and animal pathogen responsible for gastrointestinal infections. Multifrequency (9-285 GHz) EPR spectroscopy was applied to identify the high-valent intermediates (5 ≤ pH ≤ 8.5). The broad (2000 G) 9-GHz EPR spectrum consistent with the [Fe(IV) = O Por•+] intermediate was detected, and showed a clear pH dependence on the exchange-coupling of the radical (delocalized over the porphyrin moiety) due to the magnetic interaction with the ferryl iron. In addition, Trp• (for pH ≤ 6) and Tyr• (for 5 ≤ pH ≤ 8.5) species were distinguished by the advantageous resolution of their g-values in the 285-GHz EPR spectrum. The unequivocal identification of the high-valent intermediates in HPC by their distinct EPR spectra allowed us to address their reactivity towards substrates. The stabilization of an [Fe(IV) = O Trp•] species in HPC, unprecedented in monofunctional catalases and possibly involved in the oxidation of formate to the formyloxyl radical at pH ≤ 6, is reminiscent of intermediates previously identified in the catalytic cycle of bifunctional catalase-peroxidases. The 2e- oxidation of formate by the [Fe(IV) = O Por•+] species, both at basic and acidic pH conditions, involving a 1H+/2e- oxidation in a cytochrome P450 peroxygenase-like reaction is proposed. Our findings demonstrate that moonlighting by the H. pylori catalase includes formate oxidation, an enzymatic reaction possibly related to the unique strategy of the neutrophile bacterium for gastric colonization, that is the release of CO2 to regulate the pH in the acidic environment.


Assuntos
Proteínas de Bactérias , Catalase , Formiatos , Helicobacter pylori , Oxirredução , Helicobacter pylori/enzimologia , Espectroscopia de Ressonância de Spin Eletrônica/métodos , Catalase/metabolismo , Catalase/química , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Formiatos/química , Formiatos/metabolismo , Concentração de Íons de Hidrogênio , Ferro/química , Ferro/metabolismo
8.
Acta Crystallogr F Struct Biol Commun ; 80(Pt 5): 98-106, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38699971

RESUMO

Molybdenum- or tungsten-dependent formate dehydrogenases have emerged as significant catalysts for the chemical reduction of CO2 to formate, with biotechnological applications envisaged in climate-change mitigation. The role of Met405 in the active site of Desulfovibrio vulgaris formate dehydrogenase AB (DvFdhAB) has remained elusive. However, its proximity to the metal site and the conformational change that it undergoes between the resting and active forms suggests a functional role. In this work, the M405S variant was engineered, which allowed the active-site geometry in the absence of methionine Sδ interactions with the metal site to be revealed and the role of Met405 in catalysis to be probed. This variant displayed reduced activity in both formate oxidation and CO2 reduction, together with an increased sensitivity to oxygen inactivation.


Assuntos
Desulfovibrio vulgaris , Formiato Desidrogenases , Desulfovibrio vulgaris/enzimologia , Desulfovibrio vulgaris/genética , Formiato Desidrogenases/química , Formiato Desidrogenases/genética , Formiato Desidrogenases/metabolismo , Domínio Catalítico , Cristalografia por Raios X , Oxirredução , Modelos Moleculares , Formiatos/metabolismo , Formiatos/química , Dióxido de Carbono/metabolismo , Dióxido de Carbono/química , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo
9.
Metab Eng ; 84: 1-12, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38759777

RESUMO

The development of synthetic microorganisms that could use one-carbon compounds, such as carbon dioxide, methanol, or formate, has received considerable interest. In this study, we engineered Pichia pastoris and Saccharomyces cerevisiae to both synthetic methylotrophy and formatotrophy, enabling them to co-utilize methanol or formate with CO2 fixation through a synthetic C1-compound assimilation pathway (MFORG pathway). This pathway consisted of a methanol-formate oxidation module and the reductive glycine pathway. We first assembled the MFORG pathway in P. pastoris using endogenous enzymes, followed by blocking the native methanol assimilation pathway, modularly engineering genes of MFORG pathway, and compartmentalizing the methanol oxidation module. These modifications successfully enabled the methylotrophic yeast P. pastoris to utilize both methanol and formate. We then introduced the MFORG pathway from P. pastoris into the model yeast S. cerevisiae, establishing the synthetic methylotrophy and formatotrophy in this organism. The resulting strain could also successfully utilize both methanol and formate with consumption rates of 20 mg/L/h and 36.5 mg/L/h, respectively. The ability of the engineered P. pastoris and S. cerevisiae to co-assimilate CO2 with methanol or formate through the MFORG pathway was also confirmed by 13C-tracer analysis. Finally, production of 5-aminolevulinic acid and lactic acid by co-assimilating methanol and CO2 was demonstrated in the engineered P. pastoris and S. cerevisiae. This work indicates the potential of the MFORG pathway in developing different hosts to use various one-carbon compounds for chemical production.


Assuntos
Dióxido de Carbono , Formiatos , Engenharia Metabólica , Metanol , Saccharomyces cerevisiae , Formiatos/metabolismo , Metanol/metabolismo , Dióxido de Carbono/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Saccharomycetales/metabolismo , Saccharomycetales/genética
10.
Sci Rep ; 14(1): 10899, 2024 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-38740854

RESUMO

In order to obtain the best mass spectrometry identification results for using the most appropriate methods in clinical practice, we explore the optimal pretreatment methods for different species and morphologies of filamentous fungi. 98 fungal strains were treated with formic acid sandwich method, dispersion method, extraction method, and other methods using a medium element mass spectrometer (EXS3000) as a platform. Each strain had three targets, and the identification rates and confidence differences under different pre-treatment methods were compared to evaluate the identification effects of these methods. The mass spectrometry identification rates of 98 filamentous fungi obtained after pre-treatment with formic acid sandwich method, dispersion method, and extraction method were 85.71%, 82.65%, and 75.51%, respectively. The identification rate of the formic acid sandwich method was significantly higher than the other two methods (P < 0 005) has the best identification ability and the obtained confidence is also higher than the other two methods. The use of formic acid sandwich method for mass spectrometry identification of filamentous fungi can achieve ideal identification results, which is suitable for mass spectrometry identification of filamentous fungi in conventional laboratories.


Assuntos
Fungos , Espectrometria de Massas , Fungos/isolamento & purificação , Fungos/classificação , Espectrometria de Massas/métodos , Formiatos/química , Formiatos/análise , Micoses/microbiologia , Micoses/diagnóstico , Humanos
11.
Bioresour Technol ; 402: 130774, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38701983

RESUMO

Formate as an ideal mediator between the physicochemical and biological realms can be obtained from electrochemical reduction of CO2 and used to produce bio-chemicals. Yet, limitations arise when employing natural formate-utilizing microorganisms due to restricted product range and low biomass yield. This study presents a breakthrough: engineered Corynebacterium glutamicum strains (L2-L4) through modular engineering. L2 incorporates the formate-tetrahydrofolate cycle and reverse glycine cleavage pathway, L3 enhances NAD(P)H regeneration, and L4 reinforces metabolic flux. Metabolic modeling elucidates C1 assimilation, guiding strain optimization for co-fermentation of formate and glucose. Strain L4 achieves an OD600 of 0.5 and produces 0.6 g/L succinic acid. 13C-labeled formate confirms C1 assimilation, and further laboratory evolution yields 1.3 g/L succinic acid. This study showcases a successful model for biologically assimilating formate in C. glutamicum that could be applied in C1-based biotechnological production, ultimately forming a formate-based bioeconomy.


Assuntos
Biomassa , Corynebacterium glutamicum , Formiatos , Engenharia Metabólica , Ácido Succínico , Corynebacterium glutamicum/metabolismo , Formiatos/metabolismo , Engenharia Metabólica/métodos , Ácido Succínico/metabolismo , Fermentação , Modelos Biológicos , Glucose/metabolismo
12.
Cell Chem Biol ; 31(5): 932-943.e8, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38759619

RESUMO

Nucleotides perform important metabolic functions, carrying energy and feeding nucleic acid synthesis. Here, we use isotope tracing-mass spectrometry to quantitate contributions to purine nucleotides from salvage versus de novo synthesis. We further explore the impact of augmenting a key precursor for purine synthesis, one-carbon (1C) units. We show that tumors and tumor-infiltrating T cells (relative to splenic or lymph node T cells) synthesize purines de novo. Shortage of 1C units for T cell purine synthesis is accordingly a potential bottleneck for anti-tumor immunity. Supplementing 1C units by infusing formate drives formate assimilation into purines in tumor-infiltrating T cells. Orally administered methanol functions as a formate pro-drug, with deuteration enabling kinetic control of formate production. Safe doses of methanol raise formate levels and augment anti-PD-1 checkpoint blockade in MC38 tumors, tripling durable regressions. Thus, 1C deficiency can gate antitumor immunity and this metabolic checkpoint can be overcome with pharmacological 1C supplementation.


Assuntos
Carbono , Camundongos Endogâmicos C57BL , Purinas , Animais , Camundongos , Purinas/química , Purinas/farmacologia , Carbono/química , Carbono/metabolismo , Inibidores de Checkpoint Imunológico/farmacologia , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Linfócitos do Interstício Tumoral/efeitos dos fármacos , Linfócitos T/metabolismo , Linfócitos T/imunologia , Linfócitos T/efeitos dos fármacos , Formiatos/química , Formiatos/metabolismo , Formiatos/farmacologia , Metanol/química , Metanol/farmacologia , Feminino , Humanos , Linhagem Celular Tumoral
13.
J Insect Sci ; 24(3)2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38805657

RESUMO

Despite the use of various integrated pest management strategies to control the honey bee mite, Varroa destructor, varroosis remains the most important threat to honey bee colony health in many countries. In Canada, ineffective varroa control is linked to high winter colony losses and new treatment options, such as a summer treatment, are greatly needed. In this study, a total of 135 colonies located in 6 apiaries were submitted to one of these 3 varroa treatment strategies: (i) an Apivar® fall treatment followed by an oxalic acid (OA) treatment by dripping method; (ii) same as in (i) with a summer treatment consisting of formic acid (Formic Pro™); and (iii) same as in (i) with a summer treatment consisting of slow-release OA/glycerin pads (total of 27 g of OA/colony). Treatment efficacy and their effects on colony performance, mortality, varroa population, and the abundance of 6 viruses (acute bee paralysis virus [ABPV], black queen cell virus [BQCV], deformed wing virus variant A [DWV-A], deformed wing virus variant B [DWV-B], Israeli acute paralysis virus [IAPV], and Kashmir bee virus [KBV]) were assessed. We show that a strategy with a Formic Pro summer treatment tended to reduce the varroa infestation rate to below the economic fall threshold of 15 daily varroa drop, which reduced colony mortality significantly but did not reduce the prevalence or viral load of the 6 tested viruses at the colony level. A strategy with glycerin/OA pads reduced hive weight gain and the varroa infestation rate, but not below the fall threshold. A high prevalence of DWV-B was measured in all groups, which could be related to colony mortality.


Assuntos
Criação de Abelhas , Estações do Ano , Varroidae , Carga Viral , Animais , Varroidae/fisiologia , Abelhas/parasitologia , Abelhas/virologia , Criação de Abelhas/métodos , Acaricidas , Formiatos/farmacologia , Canadá
14.
Adv Microb Physiol ; 84: 51-82, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38821634

RESUMO

Formic acid (HCOOH) and dihydrogen (H2) are characteristic products of enterobacterial mixed-acid fermentation, with H2 generation increasing in conjunction with a decrease in extracellular pH. Formate and acetyl-CoA are generated by radical-based and coenzyme A-dependent cleavage of pyruvate catalysed by pyruvate formate-lyase (PflB). Formate is also the source of H2, which is generated along with carbon dioxide through the action of the membrane-associated, cytoplasmically-oriented formate hydrogenlyase (FHL-1) complex. Synthesis of the FHL-1 complex is completely dependent on the cytoplasmic accumulation of formate. Consequently, formate determines its own disproportionation into H2 and CO2 by the FHL-1 complex. Cytoplasmic formate levels are controlled by FocA, a pentameric channel that translocates formic acid/formate bidirectionally between the cytoplasm and periplasm. Each protomer of FocA has a narrow hydrophobic pore through which neutral formic acid can pass. Two conserved amino acid residues, a histidine and a threonine, at the center of the pore control directionality of translocation. The histidine residue is essential for pH-dependent influx of formic acid. Studies with the formate analogue hypophosphite and amino acid variants of FocA suggest that the mechanisms of formic acid efflux and influx differ. Indeed, current data suggest, depending on extracellular formate levels, two separate uptake mechanisms exist, both likely contributing to maintain pH homeostasis. Bidirectional formate/formic acid translocation is dependent on PflB and influx requires an active FHL-1 complex. This review describes the coupling of formate and H2 production in enterobacteria.


Assuntos
Enterobacteriaceae , Fermentação , Formiatos , Hidrogênio , Formiatos/metabolismo , Hidrogênio/metabolismo , Enterobacteriaceae/metabolismo , Enterobacteriaceae/genética , Enterobacteriaceae/enzimologia , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Formiato Desidrogenases , Hidrogenase , Complexos Multienzimáticos
15.
Nat Cancer ; 5(5): 701-715, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38698089

RESUMO

Metabolic changes contribute to cancer initiation and progression through effects on cancer cells, the tumor microenvironment and whole-body metabolism. Alterations in serine metabolism and the control of one-carbon cycles have emerged as critical for the development of many tumor types. In this Review, we focus on the mitochondrial folate cycle. We discuss recent evidence that, in addition to supporting nucleotide synthesis, mitochondrial folate metabolism also contributes to metastasis through support of antioxidant defense, mitochondrial protein synthesis and the overflow of excess formate. These observations offer potential therapeutic opportunities, including the modulation of formate metabolism through dietary interventions and the use of circulating folate cycle metabolites as biomarkers for cancer detection.


Assuntos
Ácido Fólico , Mitocôndrias , Neoplasias , Humanos , Ácido Fólico/metabolismo , Neoplasias/metabolismo , Mitocôndrias/metabolismo , Animais , Formiatos/metabolismo , Microambiente Tumoral , Metástase Neoplásica
16.
Environ Res ; 252(Pt 2): 118897, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38621631

RESUMO

The mesoporous metal oxide semiconductors exhibit unique chemical and physical characteristics, making them highly desirable for catalysis, electrochemistry, energy conversion, and energy storage applications. Here, we report the facial fabrication of mesoporous gray SnO2 (MGS) electrocatalysts employing an evaporation-induced co-assembly (EICA) approach, utilizing poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) triblock copolymers Pluronic P123 (PEO-PPO-PEO) triblock copolymer as a template for electrochemical CO2 reduction reaction (eCO2RR). By sustaining the co-assembly conditions and utilizing a thermal treatment technique based on carbon, gray mesoporous SnO2 materials with a high density of active sites and oxygen vacancies can be constructed. The MGS materials were employed in eCO2RR in a flow cell type, which exhibits excellent catalytic activity and selectivity toward formate with a high partial current density of -234 mA cm-2 and Faradaic efficiency (FE) of 93.60 % at -1.3 V vs. reversible hydrogen electrode (RHE). Interestingly, the mesoporous SnO2 with a 1.5 wt% ratio of Sn precursor to P123 surfactant (MS-1.5@350N-400A) electrode exhibits a high level of Faradaic efficiency (FE) of (98%) at a low overpotential of -0.6 VRHE, which is a seldom recorded performance for similar systems. A stable FE of 96 ± 1% was observed in the range of -0.6 to -1.2 VRHE, which is the result of a large surface area (184 m2/g) and a high number of active sites and oxygen vacancies within the mesostructured framework.


Assuntos
Dióxido de Carbono , Formiatos , Oxirredução , Compostos de Estanho , Catálise , Compostos de Estanho/química , Dióxido de Carbono/química , Formiatos/química , Porosidade , Técnicas Eletroquímicas/métodos
17.
Bioresour Technol ; 401: 130757, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38688392

RESUMO

The photosynthetic autotrophic production of microalgae is limited by the effective supply of carbon and light energy, and the production efficiency is lower than the theoretical value. Represented by methanol, C1 compounds have been industrially produced by artificial photosynthesis with a solar energy efficiency over 10%, but the complexity of artificial products is weak. Here, based on a construction of chloroplast factory, green microalgae Chlamydomonas reinhardtii CC137c was modified for the bioconversion of formate for biomass production. By screening the optimal combination of chloroplast transport peptides, the cabII-1 cTP1 fusion formate dehydrogenase showed significant enhancement on the conversion of formate with a better performance in the maintenance of light reaction activity. This work provided a new way to obtain bioproducts from solar energy and CO2 with potentially higher-than-nature efficiency by the artificial-natural hybrid photosynthesis.


Assuntos
Chlamydomonas reinhardtii , Cloroplastos , Formiatos , Cloroplastos/metabolismo , Formiatos/metabolismo , Chlamydomonas reinhardtii/metabolismo , Fotossíntese , Formiato Desidrogenases/metabolismo , Biomassa
18.
Development ; 151(10)2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38682273

RESUMO

Neurulation is a highly synchronized biomechanical process leading to the formation of the brain and spinal cord, and its failure leads to neural tube defects (NTDs). Although we are rapidly learning the genetic mechanisms underlying NTDs, the biomechanical aspects are largely unknown. To understand the correlation between NTDs and tissue stiffness during neural tube closure (NTC), we imaged an NTD murine model using optical coherence tomography (OCT), Brillouin microscopy and confocal fluorescence microscopy. Here, we associate structural information from OCT with local stiffness from the Brillouin signal of embryos undergoing neurulation. The stiffness of neuroepithelial tissues in Mthfd1l null embryos was significantly lower than that of wild-type embryos. Additionally, exogenous formate supplementation improved tissue stiffness and gross embryonic morphology in nullizygous and heterozygous embryos. Our results demonstrate the significance of proper tissue stiffness in normal NTC and pave the way for future studies on the mechanobiology of normal and abnormal embryonic development.


Assuntos
Tubo Neural , Neurulação , Tomografia de Coerência Óptica , Animais , Feminino , Camundongos , Fenômenos Biomecânicos , Embrião de Mamíferos/metabolismo , Formiato-Tetra-Hidrofolato Ligase/genética , Formiato-Tetra-Hidrofolato Ligase/metabolismo , Formiatos/metabolismo , Metilenotetra-Hidrofolato Desidrogenase (NADP)/genética , Metilenotetra-Hidrofolato Desidrogenase (NADP)/metabolismo , Camundongos Knockout , Microscopia Confocal , Mutação/genética , Tubo Neural/metabolismo , Defeitos do Tubo Neural/genética , Defeitos do Tubo Neural/metabolismo , Defeitos do Tubo Neural/patologia , Neurulação/genética , Tomografia de Coerência Óptica/métodos
19.
Wei Sheng Yan Jiu ; 53(2): 310-315, 2024 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-38604969

RESUMO

OBJECTIVE: To establish a method for twelve halobenzoquinones(HBQs) in drinking water by solid phase extraction-ultra-performance liquid chromatography coupled with electrospray-tandem mass spectrometry(SPE-UPLC-MS/MS). METHODS: The drinking water was acidified with formic acid and concentrated by Bond Elut Plexa solid phase extraction column. The sample solution was separated using Waters ACQUITY HSS T3 column(100 mm×2.1 mm, 1.8 µm) with gradient elution using methanol-water containing 0.1% formic acid as mobile phase. The target compouds were detected in negtive electrospray ionization(ESI~-) and multiple reaction monitoring. RESULTS: The concentration of twelve HBQs showed good linearity in the range 5.0-150.0 ng/mL, respectively, with the correlation coefficients greater than 0.999. The limits of detection(LOD) of twelve HBQs were lower than 2.0 ng/mL, and the limits of quantification(LOQ) for twelve HBQs were lower than 5.0 ng/mL, respectively. The recoveries of three levels in the matrix were 70.0%-84.0%. The matrix effffect was 0.08-0.64. CONCLUSION: The SPE-UPLC-MS/MS method has high sensitivity, good accuracy and fast analysis speed for the detection of halobenzoquinones in drinking water.


Assuntos
Água Potável , Formiatos , Espectrometria de Massas em Tandem , Cromatografia Líquida , Espectrometria de Massas em Tandem/métodos , Água Potável/química , Cromatografia Líquida de Alta Pressão/métodos , Extração em Fase Sólida
20.
Waste Manag ; 181: 114-127, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38608526

RESUMO

In this study, phenolic compounds using deep eutectic solvents (DES) were extracted from cork dust, and the biogas production potential of DES-treated cork dust samples was determined. The DES treatment was carried out using choline chloride and formic acid (1:2 M ratio) at various temperatures (90, 110 and 130 °C) and treatment times (20, 40 and 60 min) at a solid-to-solvent ratio of 1:10 g mL-1. The highest total phenolic content (137 mg gallic acid equivalent (GAE) g-1 dry cork dust) was achieved at 110 °C/20 min. The extracts exhibited an antioxidant capacity of up to 56.3 ± 3.1 % 1,1-diphenyl-2-picrylhydazyl (DPPH) inhibition at a dilution rate of 100. DES treatment resulted in minimal sugar solubilization at low temperatures, while approximately 42 % of the xylan fraction in the biomass degraded under severe conditions (e.g., 130 °C/60 min). Catechin, 4-hydroxybenzoic acid and gallic acid were the major phenolics in DES extracts. The biogas yield of DES-treated cork dust increased with treatment severity. The highest biogas yield (115.1mLN gVS-1) was observed at 130 °C/60 min, representing an increase of 125 % compared to the untreated sample. SEM images revealed that the surface structure of the samples became smoother after mild pretreatment and rougher after harsh pretreatment. Compositional and FTIR analyses indicated that a higher biogas formation potential was associated with increased cellulose content in the substrate, which could be attributed to hemicellulose solubilization in the hydrolysate. Overall, DES pretreatment effectively enhanced phenol extraction and anaerobic degradability.


Assuntos
Biomassa , Solventes Eutéticos Profundos , Poeira , Fenóis , Fenóis/análise , Poeira/análise , Solventes Eutéticos Profundos/química , Anaerobiose , Quercus/química , Biocombustíveis/análise , Antioxidantes/análise , Formiatos/análise , Formiatos/química
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