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Dual tasks (DTs) combining walking with a cognitive task can cause various levels of cognitive-motor interference, depending on which brain resources are recruited in each case. However, the brain activation and functional connectivity underlying cognitive-motor interferences remain to be elucidated. Therefore, this study investigated the neural correlation during different DT conditions in 40 healthy young adults (mean age: 27.53 years, 28 women). The DTs included walking during subtraction or N-Back tasks. Cognitive-motor interference was calculated, and brain activation and functional connectivity were analysed. Portable functional near-infrared spectroscopy was utilized to monitor haemodynamics in the prefrontal cortex (PFC), motor cortex and parietal cortex during each task. Walking interference (decrease in walking speed during DT) was greater than cognitive interference (decrease in cognitive performance during DT), regardless of the type of task. Brain activation in the bilateral PFC and parietal cortex was greater for walking during subtraction than for standing subtraction. Furthermore, brain activation was higher in the bilateral motor and parietal and PFCs for walking during subtraction than for walking alone, but only increased in the PFC for walking during N-Back. Coherence between the bilateral lateral PFC and between the left lateral PFC and left motor cortex was significantly greater for walking during 2-Back than for walking. The PFC, a critical brain region for organizing cognitive and motor functions, played a crucial role in integrating information coming from multiple brain networks required for completing DTs. Therefore, the PFC could be a potential target for the modulation and improvement of cognitive-motor functions during neurorehabilitation.
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Cognição , Desempenho Psicomotor , Espectroscopia de Luz Próxima ao Infravermelho , Humanos , Feminino , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Masculino , Adulto , Cognição/fisiologia , Desempenho Psicomotor/fisiologia , Adulto Jovem , Caminhada/fisiologia , Córtex Motor/fisiologia , Córtex Pré-Frontal/fisiologia , Córtex Pré-Frontal/diagnóstico por imagem , Lobo Parietal/fisiologiaRESUMO
ß-Carotene is one kind of the most important carotenoids. The major functions of ß-carotene include the antioxidant and anti-cardiovascular properties, which make it a growing market. Recently, the use of metabolic engineering to construct microbial cell factories to synthesize ß-carotene has become the latest model for its industrial production. Among these cell factories, yeasts including Saccharomyces cerevisiae and Yarrowia lipolytica have attracted the most attention because of the: security, mature genetic manipulation tools, high flux toward carotenoids using the native mevalonate pathway and robustness for large-scale fermentation. In this review, the latest strategies for ß-carotene biosynthesis, including protein engineering, promoters engineering and morphological engineering are summarized in detail. Finally, perspectives for future engineering approaches are proposed to improve ß-carotene production.
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Engenharia Metabólica , Yarrowia , beta Caroteno/genética , beta Caroteno/metabolismo , Yarrowia/genética , Yarrowia/metabolismo , Saccharomyces cerevisiae/genética , Regiões Promotoras GenéticasRESUMO
Metabolic Engineering of yeast is a critical approach to improving the production capacity of cell factories. To obtain genetically stable recombinant strains, the exogenous DNA is preferred to be integrated into the genome. Previously, we developed a Golden Gate toolkit YALIcloneNHEJ, which could be used as an efficient modular cloning toolkit for the random integration of multigene pathways through the innate non-homologous end-joining repair mechanisms of Yarrowia lipolytica. We expanded the toolkit by designing additional building blocks of homologous arms and using CRISPR technology. The reconstructed toolkit was thus entitled YALIcloneHR and designed for gene-specific knockout and integration. To verify the effectiveness of the system, the gene PEX10 was selected as the target for the knockout. This system was subsequently applied for the arachidonic acid production, and the reconstructed strain can accumulate 4.8% of arachidonic acid. The toolkit will expand gene editing technology in Y. lipolytica, which would help produce other chemicals derived from acetyl-CoA in the future.
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Sistemas CRISPR-Cas , Yarrowia , Sistemas CRISPR-Cas/genética , Yarrowia/genética , Yarrowia/metabolismo , Ácido Araquidônico/metabolismo , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Edição de Genes , Engenharia MetabólicaRESUMO
The sesquiterpene α-humulene is an important plant natural product, which has been used in the pharmaceutical industry due to its anti-inflammatory and anticancer activities. Although phytoextraction and chemical synthesis have previously been applied in α-humulene production, the low efficiency and high costs limit the development. In this study, Yarrowia lipolytica was engineered as the robust cell factory for sustainable α-humulene production. First, a chassis with high α-humulene output in the cytoplasm was constructed by integrating α-humulene synthases with high catalytic activity, optimizing the flux of mevalonate and acetyl-CoA pathways. Subsequently, the strategy of dual cytoplasmic-peroxisomal engineering was adopted in Y. lipolytica; the best strain GQ3006 generated by introducing 31 copies of 12 different genes could produce 2280.3± 38.2 mg/l (98.7 ± 4.2 mg/g dry cell weight) α-humulene, a 100-fold improvement relative to the baseline strain. To further improve the titer, a novel strategy for downregulation of squalene biosynthesis based on Cu2+ -repressible promoters was firstly established, which significantly improved the α-humulene titer by 54.2% to 3516.6 ± 34.3 mg/l. Finally, the engineered strain could produce 21.7 g/l α-humulene in a 5-L bioreactor, 6.8-fold higher than the highest α-humulene titer reported before this study. Overall, system metabolic engineering strategies used in this study provide a valuable reference for the highly sustainable production of terpenoids in Y. lipolytica.
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Sesquiterpenos , Yarrowia , Citosol/metabolismo , Engenharia Metabólica , Sesquiterpenos Monocíclicos , Sesquiterpenos/metabolismo , Yarrowia/genética , Yarrowia/metabolismoRESUMO
Hyperglycemia is considered a risk factor for the enhancement of local anesthetic-induced neurotoxicity. Transient receptor potential melastatin 7 (TRPM7), a kinase-coupled cation channel, has been implicated in a variety of neuropathological processes, including intracellular calcium disturbance and high glucose-induced neuropathy. In this study, we investigated whether TRPM7-related pathophysiology is involved in bupivacaine-induced neurotoxicity in SH-SY5Y cells and how hyperglycemia acts as a risk factor. For initial neurotoxicity evaluation, it was confirmed that cell damage and apoptosis induced by acute exposure to bupivacaine were dependent on its concentration and glucose preconditioning. High glucose preconditioning facilitated the bupivacaine-induced fast and temporary rise in intracellular free calcium concentration ([Ca2+ ]i ), which was attributed to both calcium influx through TRPM7 and calcium store release. Additionally, bupivacaine was shown to increase TRPM7-like currents, particularly in cells preconditioned with high glucose. Bupivacaine-induced neurotoxicity in hyperglycemia was correlated with extracellular signal-regulated kinase (ERK), but not protein kinase B (AKT) activation. Inhibition of TRPM7 and ERK activity alleviates bupivacaine neurotoxicity. These results suggest that therapeutically targeting TRPM7-related pathophysiological changes could be a potential strategy for treating local anesthetic-induced neurotoxicity exacerbated by hyperglycemia.
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Bupivacaína/efeitos adversos , Sinalização do Cálcio/efeitos dos fármacos , Cálcio/metabolismo , Glucose/farmacologia , Neurônios/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Canais de Cátion TRPM/metabolismo , Bupivacaína/farmacologia , Linhagem Celular Tumoral , HumanosRESUMO
Compensatory hepatocyte proliferation and other liver regenerative processes are activated to sustain normal physiological function after liver injury. A major mitogen for liver regeneration is hepatocyte growth factor (HGF), and a previous study indicated that progranulin could modulate c-met, the receptor for HGF, to initiate hepatic outgrowth from hepatoblasts during embryonic development. However, a role for progranulin in compensatory hepatocyte proliferation has not been shown previously. Therefore, this study was undertaken to clarify whether progranulin plays a regulatory role during liver regeneration. To this end, we established a partial hepatectomy regeneration model in adult zebrafish that express a liver-specific fluorescent reporter. Using this model, we found that loss of progranulin A (GrnA) function by intraperitoneal-injection of a Vivo-Morpholino impaired and delayed liver regeneration after partial hepatectomy. Furthermore, transcriptome analysis and confirmatory quantitative real-time PCR suggested that cell cycle progression and cell proliferation was not as active in the morphants as controls, which may have been the result of comparative downregulation of the HGF/c-met axis by 36 h after partial hepatectomy. Finally, liver-specific overexpression of GrnA in transgenic zebrafish caused more abundant cell proliferation after partial hepatectomy compared to wild types. Thus, we conclude that GrnA positively regulates HGF/c-met signaling to promote hepatocyte proliferation during liver regeneration.
Assuntos
Hepatectomia/métodos , Fator de Crescimento de Hepatócito/metabolismo , Hepatócitos/citologia , Regeneração Hepática , Progranulinas/metabolismo , Proteínas Proto-Oncogênicas c-met/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Animais , Proliferação de Células , Fator de Crescimento de Hepatócito/genética , Hepatócitos/metabolismo , Organogênese , Progranulinas/genética , Proteínas Proto-Oncogênicas c-met/genética , Transdução de Sinais , Peixe-Zebra , Proteínas de Peixe-Zebra/genéticaRESUMO
RATIONALE: Interactions of drug molecules and proteins play important roles in physiological and pathological processes in vivo. It is of significance to establish a reliable strategy for studying protein-drug ligand interactions and would be helpful for the design and screening of new drugs in pharmacological research. METHODS: The interactions between four indole alkaloids (IAs) extracted from Ophiorrhiza japonica (O. japonica) and myoglobin (Mb) protein were investigated using a multi-spectrometric and computational method of native electrospray ionization mass spectrometry (native ESI-MS), hydrogen/deuterium exchange mass spectrometry (HDX-MS), circular dichroism (CD) and molecular docking (MD). RESULTS: The IA-bound Mb complexes were analyzed using native ESI-MS, with the obtained protein-to-ligand stoichiometry at 1:1, 1:2 and 1:3. Binding constants were measured according to the interpretation of MS spectra. MD complemented MS measurements, probing the binding sites and modes of the four IAs to Mb. Analyses involving CD and HDX-MS demonstrated that exposure to IAs could affect the conformation of Mb by decreasing the α-helix content and made Mb more susceptible to HDX at the backbone. CONCLUSIONS: A new MS-based integrated analysis method has been developed to successfully study the interactions of Mb and IAs extracted from O. japonica. The experimental and calculation results have good consistency, revealing all of the four IA molecules could bind to Mb to form 1:1, 1:2 and 1:3 Mb-IA complexes. The order of binding ability of these IAs to Mb was ophiorrhine B > compound C > ophiorrhine A > compound D. CD and HDX-MS results indicated that binding with IAs destabilizes Mb. HDX-MS analysis suggests that Mb becomes more susceptible to HDX, indicating that binding with IAs destabilizes the structure of Mb. In addition, the interaction with IAs affected the overall structure of Mb, ascribed to the decrease of α-helix content and less folding of the backbone.
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Alcaloides Indólicos/farmacologia , Mioglobina/metabolismo , Extratos Vegetais/farmacologia , Rubiaceae/química , Animais , Dicroísmo Circular , Cavalos , Alcaloides Indólicos/química , Simulação de Acoplamento Molecular , Mioglobina/química , Extratos Vegetais/química , Conformação Proteica em alfa-Hélice/efeitos dos fármacos , Espectrometria de Massas por Ionização por ElectrosprayRESUMO
CRSBP-1 (mammalian LYVE-1) is a membrane glycoprotein highly expressed in lymphatic endothelial cells (LECs). It has multiple ligands, including hyaluronic acid (HA) and growth factors/cytokines (e.g., PDGF-BB and VEGF-A) containing CRS motifs (clusters of basic amino-acid residues). The ligand binding activities are mediated by Link module and acidic-amino-acid-rich (AAAR) domains, respectively. These CRSBP-1/LYVE-1 ligands have been shown to induce opening of lymphatic intercellular junctions in LEC monolayers and in lymphatic vessels in wild-type mice. We hypothesize that CRSBP-1/LYVE-1 ligands, particularly CRS-containing growth factors/cytokines, are secreted by immune and cancer cells for lymphatic entry during adaptive immune responses and lymphatic metastasis. We have looked into the origin of the Link module and AAAR domain of LYVE-1 in evolution and its association with the development of lymph nodes and efficient adaptive immunity. Lymph nodes represent the only major recent innovation of the adaptive immune systems in evolution particularly to mammals and bird. Here we demonstrate that the development of the LYVE-1 gene with the AAAR domain in evolution is associated with acquisition of lymph nodes and adaptive immunity. LYVE-1 from other species, which have no lymph nodes, lack the AAAR domain and efficient adaptive immunity. Synthetic CRSBP-1 ligands PDGF and VEGF peptides, which contain the CRS motifs of PDGF-BB and VEGF-A, respectively, specifically bind to CRSBP-1 but do not interact with either PDGFßR or VEGFR2. These peptides function as adjuvants by enhancing adaptive immunity of pseudorabies virus (PRV) vaccine in pigs. These results support the notion that LYVE-1 is involved in adaptive immunity in mammals.
Assuntos
Imunidade Adaptativa , Aminoácidos Acídicos/metabolismo , Evolução Molecular , Linfonodos/imunologia , Proteínas de Membrana/química , Proteínas de Membrana/genética , Imunidade Adaptativa/efeitos dos fármacos , Adjuvantes Imunológicos/farmacologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Feminino , Ligantes , Linfonodos/efeitos dos fármacos , Proteínas de Membrana/metabolismo , Peptídeos/farmacologia , Filogenia , Fator de Crescimento Derivado de Plaquetas/farmacologia , Domínios Proteicos , Vacinas contra Pseudorraiva/imunologia , Alinhamento de Sequência , Tubarões , Homologia Estrutural de Proteína , Relação Estrutura-Atividade , Sus scrofa , Fator A de Crescimento do Endotélio Vascular/farmacologia , Peixe-ZebraRESUMO
In this work, we propose a filter structure using a one-dimensional ferroelectric-dielectric periodic multilayer, air/[(ABA)Ns C]Np(ABA)Ns /air, where Ns and Np are the two numbers of periods. Here, B is a dielectric material of SiO2, C is the same as B with a different thickness, and A is taken to be a ferroelectric material Ba55Sr45TiO3+30%Mg2SiO4, whose dielectric constant is very high (ϵ=439 at 10 GHz). The results show that the transmittance spectra have Ns-channel groups at microwave frequencies and these groups can be classified into two types. The first type has only one channel group with Np narrower channels. The other has Ns-1 groups, each of which has Np+1 broader channels. In this filter structure the group number and channel number of each group can be determined simply by changing Ns and Np.
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OBJECTIVE: To study the association between single nucleotide polymorphisms(SNP) in toll-like receptors (TLR) 2 and 5 genes and the susceptibility to neonatal sepsis. METHODS: One hundred and fourteen newborn infants who were diagnosed with clinical sepsis (case group) between May 2011 and January 2014 and 172 newborn infants without infection(control group) were enrolled in this study. The polymorphisms of TLR2 (rs5743708 and rs3804099) and TLR5 (rs5744105) were analyzed using a SNaPshot multiplex reaction to compare the genotypic and allelic frequencies between two groups. The relationship between TLR genotypes and susceptibility to sepsis was analyzed by logistic regression models. RESULTS: Significant differences in genotypic frequencies of TLR2 rs3804099 (C/T) and TLR5 rs5744105 (C/G) were found between the two groups (P<0.05), but there was no significant difference in allelic frequencies of all the SNPs above between the two groups (P>0.05). The genotype on TLR2 rs5743708 was GG and no mutation was found in both groups. In regression models, birth weight (OR=3.065; P<0.05) and gestational age (OR=3.301; P<0.05) were closely associated with neonatal sepsis. Sex (OR=1.107, P>0.05), polymorphisms in rs3804099 (OR=0.876; P>0.05) and polymorphisms in rs5744105 (OR=0.820; P>0.05) genes were not risk factors for neonatal sepsis. CONCLUSIONS: TLR2 and 5 polymorphisms (rs5743708, rs3804099 and rs5744105) may not serve as the susceptible gene for sepsis in newborn infants.
Assuntos
Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Sepse/genética , Receptor 2 Toll-Like/genética , Receptor 5 Toll-Like/genética , Feminino , Humanos , Recém-Nascido , Modelos Logísticos , MasculinoRESUMO
A combination of N/S/Fe K-edge X-ray absorption spectroscopy (XAS), X-ray diffraction data, and density functional theory (DFT) calculations provides an efficient way to unambiguously delineate the electronic structures and bonding characters of Fe-S, N-O, and Fe-N bonds among the direduced-form Roussin's red ester (RRE) [Fe2(µ-SPh)2(NO)4](2-)(1) with {Fe(NO)2}(10)-{Fe(NO)2}(10) core, the reduced-form RRE [Fe2(µ-SPh)2(NO)4](-)(3) with {Fe(NO)2}(9)-{Fe(NO)2}(10) core, and RRE [Fe2(µ-SPh)2(NO)4] (4) with {Fe(NO)2}(9)-{Fe(NO)2}(9) core. The major contributions of highest occupied molecular orbital (HOMO) 113α/ß in complex 1 is related to the antibonding character between Fe(d) and Fe(d), Fe(d), and S atoms, and bonding character between Fe(d) and NO(π*). The effective nuclear charge (Zeff) of Fe site can be increased by removing electrons from HOMO to shorten the distances of Fe···Fe and Fe-S from 1 to 3 to 4 or, in contrast, to increase the Fe-N bond lengths from 1 to 3 to 4. The higher IR νNO stretching frequencies (1761, 1720 cm(-1) (4), 1680, 1665 cm(-1) (3), and 1646, 1611, 1603 cm(-1) (1)) associated with the higher transition energy of N1s âσ*(NO) (412.6 eV (4), 412.3 eV (3), and 412.2 eV (1)) and the higher Zeff of Fe derived from the transition energy of Fe1s â Fe3d (7113.8 eV (4), 7113.5 eV (3), and 7113.3 eV (1)) indicate that the N-O bond distances of these complexes are in the order of 1 > 3 > 4. The N/S/Fe K-edge XAS spectra as well as DFT computations reveal the reduction of complex 4 yielding complex 3 occurs at Fe, S, and NO; in contrast, reduction mainly occurs at Fe site from complex 3 to complex 1.
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Ferro/química , Óxidos de Nitrogênio/química , Elétrons , Estrutura Molecular , Óxido Nítrico/química , Óxidos de Nitrogênio/síntese química , Teoria QuânticaRESUMO
Bisphenol F (BPF) has been extensively utilized in daily life, which brings new hazards to male reproductive health. However, the specific functional mechanism is still unclear. Both cell and animal models were utilized for exploring the role of RNA methylation and ferroptosis and its underlying mechanisms in male reproductive injury induced by BPF. In animal model, BPF severely destroyed the integrity of the blood-testis barrier (BTB) and induced ferroptosis. Furthermore, BPF significantly affected the barrier function of TM4 cells and promoted ferroptosis. Importantly, ChIP assays revealed that BPF inhibited AR transcriptional regulation of FTO and FTO expression was downregulated in TM4 cells. Overexpression of FTO prevented the impairment of BTB by inhibiting ferroptosis in TM4 cells. Mechanistically, FTO could significantly down-regulate the m6A modification level of TfRc and SLC7A11 mRNA through MeRIP experiment. RIP experiments showed that YTHDF1 can bind to TfRc mRNA and promote its translation while YTHDF2 could bind to SLC7A11 mRNA and reduce its mRNA stability. Therefore, our results suggest that FTO plays a key role in BPF induced male reproductive toxicity through YTHDF1-TfRc axis and YTHDF2-SLC7A11 axis and may provide new ideas and methods for the prevention and treatment of male reproductive diseases associated with environmental pollutants.
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The aim of this study is to combine flaxseed oil (FO), rich in α-linolenic acid (ALA), with Sunite sheep tail fat (STF) through a lipase-catalyzed transesterification reaction, in order to produce an edible oil with a fatty acid ratio suitable for human needs. Initially, the optimal conditions for esterification were determined using the Box-Behnken design, with the measurement criterion being the content of ALA at the sn-2 position. The results indicated that the highest content of sn-2 ALA was obtained under the conditions of using 6.8 wt% Lipozyme®RMIM as the catalyst, a reaction temperature of 57°C, a reaction time of 3.3 h, and a substrate mass ratio of 5.6:4.4 for STF and FO. This led to the rapid breaking and recombining of molecular bonds, resulting in the interesterified fat (IF) with the highest content of ALA at the sn-2 position. Comparing STF and FO, IF exhibited excellent fatty acid composition and content. Furthermore, IF had a lower melting point and crystallization temperature compared to STF, and its solid fat content decreased with increasing temperature, completely melting at temperatures above 30°C. Thus, IF is a synthesized fat with excellent properties from both animal and vegetable sources.
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Gibberellic acid (GA3), produced industrially by Fusarium fujikuroi, stands as a crucial plant growth regulator extensively employed in the agriculture filed while limited understanding of the global metabolic network hinders researchers from conducting rapid targeted modifications. In this study, a small-molecule compounds-based targeting technology was developed to increase GA3 production. Firstly, various small molecules were used to target key nodes of different pathways and the result displayed that supplement of terbinafine improved significantly GA3 accumulation, which reached to 1.08 g/L. Subsequently, lipid and squalene biosynthesis pathway were identified as the key pathways influencing GA3 biosynthesis by transcriptomic analysis. Thus, the strategies including in vivo metabolic engineering modification and in vitro supplementation of lipid substrates were adopted, both contributed to an enhanced GA3 yield. Finally, the engineered strain demonstrated the ability to achieve a GA3 yield of 3.24 g/L in 5 L bioreactor when utilizing WCO as carbon source and feed.
Assuntos
Fusarium , Giberelinas , Fermentação , Fusarium/genética , Fusarium/química , Reatores Biológicos , LipídeosRESUMO
Benzo[a]pyrene (BaP) is associated with the development of lung cancer, but the underlying mechanism has not been completely clarified. Here, we used 10⯵M BaP to induce malignant transformation of human bronchial epithelial BEAS-2B cells, named BEAS-2B-T. Results indicated that BaP (6.25, 12.5 and 25⯵M) treatment significantly promoted the migration and invasion of BEAS-2B-T cells. Meanwhile, BaP exposure inhibited ferroptosis in BEAS-2B-T, ferroptosis-related indexes Fe2+, malondialdehyde (MDA), lipid peroxidation (LPO) and reactive oxygen species (ROS) decreased significantly. The protein level of ferroptosis-related molecule transferrin receptor (TFRC) decreased significantly, while solute carrier family 7 membrane 11 (SLC7A11), ferritin heavy chain 1 (FTH1) and glutathione peroxidase 4 (GPX4) increased significantly. The intervention of ferroptosis dramatically effected the migration and invasion of BEAS-2B-T induced by BaP. Furthermore, the expression of YTH N6-methyladenosine RNA binding protein 1 (YTHDF1) was markedly increased after BaP exposure. YTHDF1 knockdown inhibited BEAS-2B-T migration and invasion by promoting ferroptosis. In the meantime, the contents of Fe2+, MDA, LPO and ROS increased significantly, TFRC was markedly increased, and SLC7A11, FTH1, and GPX4 were markedly decreased. Moreover, overexpression of YTHDF1 promoted BEAS-2B-T migration and invasion by inhibiting ferroptosis. Importantly, knockdown of YTHDF1 promoted ferroptosis and reduced BEAS-2B-T migration and invasion during BaP exposure, and overexpression of YTHDF1 increased migration and invasion of BEAS-2B-T by inhibiting ferroptosis during BaP exposure. RNA immunoprecipitation assays indicated that the binding of YTHDF1 to SLC7A11 and FTH1 markedly increased after YTHDF1 overexpression. Therefore, we concluded that BaP promotes the malignant progression of BEAS-2B-T cells through YTHDF1 upregulating SLC7A11 and FTH1 to inhibit ferroptosis. This study reveals new epigenetic and ferroptosis markers for preventing and treating lung cancer induced by environmental carcinogens.
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Benzo(a)pireno , Movimento Celular , Ferroptose , Ferroptose/efeitos dos fármacos , Humanos , Benzo(a)pireno/toxicidade , Movimento Celular/efeitos dos fármacos , Linhagem Celular , Transformação Celular Neoplásica/induzido quimicamente , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/efeitos dos fármacos , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/patologia , Espécies Reativas de Oxigênio/metabolismo , Receptores da Transferrina/metabolismo , Receptores da Transferrina/genética , Sistema y+ de Transporte de Aminoácidos/metabolismo , Sistema y+ de Transporte de Aminoácidos/genética , Proteínas de Ligação a RNA/metabolismo , Proteínas de Ligação a RNA/genética , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/induzido quimicamente , Neoplasias Pulmonares/genética , Peroxidação de Lipídeos/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/metabolismo , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/genética , Ferritinas , Oxirredutases , Antígenos CDRESUMO
Thiathiophthene (TTP), a planar molecule with two fused heterocyclic five-membered rings and an essentially linear S-S-S bond, is a molecule of great interest due to its unique chemical bondings. To elucidate the remarkable bonding nature, a combined experimental and theoretical study on the electron density distribution of 2,5-dimethyl-3,4-trimethylene-6a-TTP (1) is investigated based on a multipole model through high-resolution X-ray diffraction data experimentally and on the density functional calculations (DFT) theoretically. In addition, S K-edge X-ray absorption spectroscopy (XAS) is measured to verify the chemical bonding concerning the sulfur atoms. The molecule can be firmly described as 10π electron with aromatic character among the eight atoms, S3C5, of the two fused five-membered rings plus three-center four-electron σ character along the S-S-S bond. Such bonding description is verified with the calculated XAS spectrum, where the pre-edge absorption for transitions from S 1s to π* and σ* are located. The three-center four-electron S-S-S σ bond makes the terminal S atoms richer in electron density than the central one.
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Compostos Heterocíclicos de 4 ou mais Anéis/química , Teoria Quântica , Sulfetos/química , Enxofre/química , Espectroscopia por Absorção de Raios X , Estrutura MolecularRESUMO
Liquid fermentation is the primary method for GA3 production usingFusarium fujikuroi. However, production capacity is limited due to unknown metabolic pathways. To address this, we constructed a genome-scale metabolic model (iCY1235) with 1753 reactions, 1979 metabolites, and 1235 genes to understand the GA3 regulation mechanisms. The model was validated by analyzing growth rates under different glucose uptake rates and identifying essential genes. We used the model to optimize fermentation conditions, including carbon sources and dissolved oxygen. Through the OptForce algorithm, we identified 20 reactions as targets. Overexpressing FFUJ_02053 and FFUJ_14337 resulted in a 37.5 and 75% increase in GA3 titers, respectively. These targets enhance carbon flux toward GA3 production. Our model holds promise for guiding the metabolic engineering of F. fujikuroi to achieve targeted overproduction. In summary, our study utilizes the iCY1235 model to understand GA3 regulation, optimize fermentation conditions, and identify specific targets for enhancing GA3 production through metabolic engineering.
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Fusarium , Giberelinas , Giberelinas/metabolismo , Fermentação , Redes e Vias MetabólicasRESUMO
The reversible redox transformations [(NO)(2)Fe(S(t)Bu)(2)](-) â [Fe(µ-S(t)Bu)(NO)(2)](2)(2-) â [Fe(µ-S(t)Bu)(NO)(2)](2)(-) â [Fe(µ-S(t)Bu)(NO)(2)](2) and [cation][(NO)(2)Fe(SEt)(2)] â [cation](2)[(NO)(2)Fe(SEt)(2)] (cation = K(+)-18-crown-6 ether) are demonstrated. The countercation of the {Fe(NO)(2)}(9) dinitrosyliron complexes (DNICs) functions to control the formation of the {Fe(NO)(2)}(10){Fe(NO)(2)}(10) dianionic reduced Roussin's red ester (RRE) [PPN](2)[Fe(µ-SR)(NO)(2)](2) or the {Fe(NO)(2)}(10) dianionic reduced monomeric DNIC [K(+)-18-crown-6 ether](2)[(NO)(2)Fe(SR)(2)] upon reduction of the {Fe(NO)(2)}(9) DNICs [cation][(NO)(2)Fe(SR)(2)] (cation = PPN(+), K(+)-18-crown-6 ether; R = alkyl). The binding preference of ligands [OPh](-)/[SR](-) toward the {Fe(NO)(2)}(10){Fe(NO)(2)}(10) motif of dianionic reduced RRE follows the ligand-displacement series [SR](-) > [OPh](-). Compared to the Fe K-edge preedge energy falling within the range of 7113.6-7113.8 eV for the dinuclear {Fe(NO)(2)}(9){Fe(NO)(2)}(9) DNICs and 7113.4-7113.8 eV for the mononuclear {Fe(NO)(2)}(9) DNICs, the {Fe(NO)(2)}(10) dianionic reduced monomeric DNICs and the {Fe(NO)(2)}(10){Fe(NO)(2)}(10) dianionic reduced RREs containing S/O/N-ligation modes display the characteristic preedge energy 7113.1-7113.3 eV, which may be adopted to probe the formation of the EPR-silent {Fe(NO)(2)}(10)-{Fe(NO)(2)}(10) dianionic reduced RREs and {Fe(NO)(2)}(10) dianionic reduced monomeric DNICs in biology. In addition to the characteristic Fe/S K-edge preedge energy, the IR ν(NO) spectra may also be adopted to characterize and discriminate [(NO)(2)Fe(µ-S(t)Bu)](2) [IR ν(NO) 1809 vw, 1778 s, 1753 s cm(-1) (KBr)], [Fe(µ-S(t)Bu)(NO)(2)](2)(-) [IR ν(NO) 1674 s, 1651 s cm(-1) (KBr)], [Fe(µ-S(t)Bu)(NO)(2)](2)(2-) [IR ν(NO) 1637 m, 1613 s, 1578 s, 1567 s cm(-1) (KBr)], and [K-18-crown-6 ether](2)[(NO)(2)Fe(SEt)(2)] [IR ν(NO) 1604 s, 1560 s cm(-1) (KBr)].
Assuntos
Compostos de Ferro/química , Óxido Nítrico/química , Compostos Nitrosos/química , Éteres de Coroa/química , Espectroscopia de Ressonância de Spin Eletrônica , Cinética , Ligantes , Modelos Moleculares , Estrutura Molecular , Oxirredução , Teoria Quântica , Termodinâmica , Espectroscopia por Absorção de Raios XRESUMO
Gibberellic acid (GA3) is a plant growth hormone that plays an important role in the production of crops, fruits, and vegetables with a wide market share. Due to intrinsic advantages, liquid fermentation of Fusarium fujikuroi has become the sole method for industrial GA3 production, but the broader application of GA3 is hindered by low titer. In this study, we combined atmospheric and room-temperature plasma (ARTP) with ketoconazole-based screening to obtain the mutant strain 3-6-1 with high yield of GA3. Subsequently, the medium composition and fermentation parameters were systematically optimized to increase the titer of GA3, resulting in a 2.5-fold increase compared with the titer obtained under the initial conditions. Finally, considering that the strain is prone to substrate inhibition and glucose repression, a new strategy of fed-batch fermentation was adopted to increase the titer of GA3 to 575.13 mg/L, which was 13.86% higher than the control. The strategy of random mutagenesis combined with selection and fermentation optimization developed in this study provides a basis for subsequent research on the industrial production of GA3.
RESUMO
Arachidonic acid is an essential ω-6 polyunsaturated fatty acid, which plays a significant role in cardiovascular health and neurological development, leading to its wide use in the food and pharmaceutical industries. Traditionally, ARA is obtained from deep-sea fish oil. However, this source is limited by season and is depleting the already threatened global fish stocks. With the rapid development of synthetic biology in recent years, oleaginous fungi have gradually attracted increasing attention as promising microbial sources for large-scale ARA production. Numerous advanced technologies including metabolic engineering, dynamic regulation of fermentation conditions, and multiomics analysis were successfully adapted to increase ARA synthesis. This review summarizes recent advances in the bioengineering of oleaginous fungi for ARA production. Finally, perspectives for future engineering approaches are proposed to further improve the titer yield and productivity of ARA.