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1.
Microb Cell Fact ; 23(1): 194, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38970033

RESUMEN

BACKGROUND: Biotransformation of CO2 into high-value-added carbon-based products is a promising process for reducing greenhouse gas emissions. To realize the green transformation of CO2, we use fatty acids as carbon source to drive CO2 fixation to produce succinate through a portion of the 3-hydroxypropionate (3HP) cycle in Cupriavidus necator H16. RESULTS: This work can achieve the production of a single succinate molecule from one acetyl-CoA molecule and two CO2 molecules. It was verified using an isotope labeling experiment utilizing NaH13CO3. This implies that 50% of the carbon atoms present in succinate are derived from CO2, resulting in a twofold increase in efficiency compared to prior methods of succinate biosynthesis that relied on the carboxylation of phosphoenolpyruvate or pyruvate. Meanwhile, using fatty acid as a carbon source has a higher theoretical yield than other feedstocks and also avoids carbon loss during acetyl-CoA and succinate production. To further optimize succinate production, different approaches including the optimization of ATP and NADPH supply, optimization of metabolic burden, and optimization of carbon sources were used. The resulting strain was capable of producing succinate to a level of 3.6 g/L, an increase of 159% from the starting strain. CONCLUSIONS: This investigation established a new method for the production of succinate by the implementation of two CO2 fixation reactions and demonstrated the feasibility of ATP, NADPH, and metabolic burden regulation strategies in biological carbon fixation.


Asunto(s)
Dióxido de Carbono , Cupriavidus necator , Ácidos Grasos , Ácido Succínico , Dióxido de Carbono/metabolismo , Cupriavidus necator/metabolismo , Ácidos Grasos/metabolismo , Ácido Succínico/metabolismo , Acetilcoenzima A/metabolismo , NADP/metabolismo
2.
Astrobiology ; 24(7): 710-720, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39023355

RESUMEN

In a previous experiment, we demonstrated the capability of flow cytometry as a potential life detection technology for icy moons using exogenous fluorescent stains (Wallace et al., 2023). In this companion experiment, we demonstrated the capability of flow cytometry to detect life using intrinsically fluorescent biomolecules in addition to exogenous stains. We used a method similar to our previous work to positively identify six classes of intrinsically fluorescent biomolecules: flavins, carotenoids, chlorophyll, tryptophan, NAD+, and NAD(P)H. We demonstrated the effectiveness of this method with six known organisms and known abiotic material and showed that the cytometer is easily able to distinguish the known organisms and the known abiotic material by using the intrinsic fluorescence of these six biomolecules. To simulate a life detection experiment on an icy moon lander, we used six natural samples with unknown biotic and abiotic content. We showed that flow cytometry can identify all six intrinsically fluorescent biomolecules and can separate the biotic material from the known abiotic material on scatter plots. The use of intrinsically fluorescent biomolecules in addition to exogenous stains will potentially cast a wider net for life detection on icy moons using flow cytometry.


Asunto(s)
Citometría de Flujo , Citometría de Flujo/métodos , Colorantes Fluorescentes/química , Fluorescencia , Exobiología/métodos , Triptófano/análisis , Clorofila/análisis , NAD/análisis , Carotenoides/análisis , NADP/análisis
3.
Molecules ; 29(13)2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38999045

RESUMEN

1,4-diaminobutane is widely used in the industrial production of polymers, pharmaceuticals, agrochemicals and surfactants. Owing to economic and environmental concerns, there has been a growing interest in using microbes to produce 1,4-diaminobutane. However, there is lack of research on the influence of cofactors pyridoxal phosphate (PLP) and NADPH on the synthesis of 1,4-diaminobutane. PLP serves as a cofactor of ornithine decarboxylase in the synthesis of 1,4-diaminobutane. Additionally, the synthesis of 1 mol 1,4-diaminobutane requires 2 mol NADPH, thus necessitating consideration of NADPH balance in the efficient synthesis of 1,4-diaminobutane by Escherichia coli. The aim of this study was to enhance the synthesis efficiency of 1,4-diaminobutane through increasing production of PLP and NADPH. By optimizing the expression of the genes associated with synthesis of PLP and NADPH in E. coli, cellular PLP and NADPH levels increased, and the yield of 1,4-diaminobutane also increased accordingly. Ultimately, using glucose as the primary carbon source, the yield of 1,4-diaminobutane in the recombinant strain NAP19 reached 272 mg/L·DCW, by increased 79% compared with its chassis strain.


Asunto(s)
Escherichia coli , NADP , Fosfato de Piridoxal , Escherichia coli/genética , Escherichia coli/metabolismo , Fosfato de Piridoxal/metabolismo , NADP/metabolismo , Glucosa/metabolismo , Ingeniería Metabólica/métodos
4.
Appl Microbiol Biotechnol ; 108(1): 410, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38976076

RESUMEN

We characterise a reversible bacterial zinc-containing benzyl alcohol dehydrogenase (BaDH) accepting either NAD+ or NADP+ as a redox cofactor. Remarkably, its redox cofactor specificity is pH-dependent with the phosphorylated cofactors favored at lower and the dephospho-forms at higher pH. BaDH also shows different steady-state kinetic behavior with the two cofactor forms. From a structural model, the pH-dependent shift may affect the charge of a histidine in the 2'-phosphate-binding pocket of the redox cofactor binding site. The enzyme is phylogenetically affiliated to a new subbranch of the Zn-containing alcohol dehydrogenases, which share this conserved residue. BaDH appears to have some specificity for its substrate, but also turns over many substituted benzyl alcohol and benzaldehyde variants, as well as compounds containing a conjugated C=C double bond with the aldehyde carbonyl group. However, compounds with an sp3-hybridised C next to the alcohol/aldehyde group are not or only weakly turned over. The enzyme appears to contain a Zn in its catalytic site and a mixture of Zn and Fe in its structural metal-binding site. Moreover, we demonstrate the use of BaDH in an enzyme cascade reaction with an acid-reducing tungsten enzyme to reduce benzoate to benzyl alcohol. KEY POINTS: •Zn-containing BaDH has activity with either NAD + or NADP+ at different pH optima. •BaDH converts a broad range of substrates. •BaDH is used in a cascade reaction for the reduction of benzoate to benzyl alcohol.


Asunto(s)
Oxidorreductasas de Alcohol , Alcohol Bencilo , Coenzimas , NADP , Oxidación-Reducción , Zinc , Concentración de Iones de Hidrógeno , NADP/metabolismo , Especificidad por Sustrato , Alcohol Bencilo/metabolismo , Alcohol Bencilo/química , Cinética , Zinc/metabolismo , Coenzimas/metabolismo , Oxidorreductasas de Alcohol/metabolismo , Oxidorreductasas de Alcohol/química , Oxidorreductasas de Alcohol/genética , NAD/metabolismo , Benzaldehídos/metabolismo , Benzaldehídos/química , Dominio Catalítico , Sitios de Unión , Filogenia , Modelos Moleculares
5.
Nat Commun ; 15(1): 5857, 2024 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-38997257

RESUMEN

Cancer cells depend on nicotinamide adenine dinucleotide phosphate (NADPH) to combat oxidative stress and support reductive biosynthesis. One major NADPH production route is the oxidative pentose phosphate pathway (committed step: glucose-6-phosphate dehydrogenase, G6PD). Alternatives exist and can compensate in some tumors. Here, using genetically-engineered lung cancer mouse models, we show that G6PD ablation significantly suppresses KrasG12D/+;Lkb1-/- (KL) but not KrasG12D/+;P53-/- (KP) lung tumorigenesis. In vivo isotope tracing and metabolomics reveal that G6PD ablation significantly impairs NADPH generation, redox balance, and de novo lipogenesis in KL but not KP lung tumors. Mechanistically, in KL tumors, G6PD ablation activates p53, suppressing tumor growth. As tumors progress, G6PD-deficient KL tumors increase an alternative NADPH source from serine-driven one carbon metabolism, rendering associated tumor-derived cell lines sensitive to serine/glycine depletion. Thus, oncogenic driver mutations determine lung cancer dependence on G6PD, whose targeting is a potential therapeutic strategy for tumors harboring KRAS and LKB1 co-mutations.


Asunto(s)
Glucosafosfato Deshidrogenasa , Homeostasis , Neoplasias Pulmonares , NADP , Oxidación-Reducción , Proteínas Serina-Treonina Quinasas , Proteínas Proto-Oncogénicas p21(ras) , Glucosafosfato Deshidrogenasa/metabolismo , Glucosafosfato Deshidrogenasa/genética , Animales , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Proteínas Proto-Oncogénicas p21(ras)/genética , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Serina-Treonina Quinasas/genética , NADP/metabolismo , Ratones , Humanos , Línea Celular Tumoral , Lipogénesis/genética , Proteína p53 Supresora de Tumor/metabolismo , Proteína p53 Supresora de Tumor/genética , Quinasas de la Proteína-Quinasa Activada por el AMP/genética , Quinasas de la Proteína-Quinasa Activada por el AMP/metabolismo , Vía de Pentosa Fosfato/genética , Proteínas Quinasas Activadas por AMP/metabolismo , Masculino , Ratones Noqueados , Femenino , Mutación
6.
J Phys Chem B ; 128(29): 7148-7159, 2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-38991231

RESUMEN

NADPH-cytochrome P450 reductase (CPR) plays a vital role as a redox partner for mammalian cytochrome P450 enzymes (P450s), facilitating the transfer of two electrons from NADPH to the P450 heme center in a sequential manner. Previous experimental studies revealed substantial domain movements of CPR, transitioning between closed and open states during the electron transfer (ET) cycle. These transitions are essential and are influenced by the binding of NADPH or the release of NADP+. However, the intricate molecular mechanisms governing the CPR-mediated ET cycle have largely remained elusive. This study employed molecular dynamics (MD) simulation techniques to explore the dissociation of NADP+ from CPR, a crucial step preceding the initial ET from CPR to a P450. Alongside the binding structure of NADP+ observed in a crystal structure (pose I), our MD simulations identified an alternative binding structure (pose II). Although pose II exhibits slightly lower stability than pose I, it can be formed through an approximate 210° counterclockwise rotation of the adenine group, with a free energy barrier of only 2.76 kcal/mol. The simulation results further suggest that NADP+ dissociation involves a tentative formation of pose II from pose I before complete dissociation, and that the binding of NADP+ to CPR is primarily governed by nonbonded interactions within the adenosine binding pocket.


Asunto(s)
Simulación de Dinámica Molecular , NADPH-Ferrihemoproteína Reductasa , NADP , NADPH-Ferrihemoproteína Reductasa/química , NADPH-Ferrihemoproteína Reductasa/metabolismo , NADP/metabolismo , NADP/química , Termodinámica
7.
Proc Natl Acad Sci U S A ; 121(26): e2318570121, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38905238

RESUMEN

Hydrogen isotope ratios (δ2H) represent an important natural tracer of metabolic processes, but quantitative models of processes controlling H-fractionation in aquatic photosynthetic organisms are lacking. Here, we elucidate the underlying physiological controls of 2H/1H fractionation in algal lipids by systematically manipulating temperature, light, and CO2(aq) in continuous cultures of the haptophyte Gephyrocapsa oceanica. We analyze the hydrogen isotope fractionation in alkenones (αalkenone), a class of acyl lipids specific to this species and other haptophyte algae. We find a strong decrease in the αalkenone with increasing CO2(aq) and confirm αalkenone correlates with temperature and light. Based on the known biosynthesis pathways, we develop a cellular model of the δ2H of algal acyl lipids to evaluate processes contributing to these controls on fractionation. Simulations show that longer residence times of NADPH in the chloroplast favor a greater exchange of NADPH with 2H-richer intracellular water, increasing αalkenone. Higher chloroplast CO2(aq) and temperature shorten NADPH residence time by enhancing the carbon fixation and lipid synthesis rates. The inverse correlation of αalkenone to CO2(aq) in our cultures suggests that carbon concentrating mechanisms (CCM) do not achieve a constant saturation of CO2 at the Rubisco site, but rather that chloroplast CO2 varies with external CO2(aq). The pervasive inverse correlation of αalkenone with CO2(aq) in the modern and preindustrial ocean also suggests that natural populations may not attain a constant saturation of Rubisco with the CCM. Rather than reconstructing growth water, αalkenone may be a powerful tool to elucidate the carbon limitation of photosynthesis.


Asunto(s)
Dióxido de Carbono , Haptophyta , Lípidos , Fotosíntesis , Dióxido de Carbono/metabolismo , Haptophyta/metabolismo , Lípidos/química , Hidrógeno/metabolismo , Cloroplastos/metabolismo , Deuterio/metabolismo , NADP/metabolismo , Temperatura , Fraccionamiento Químico/métodos , Metabolismo de los Lípidos
8.
Nat Commun ; 15(1): 5115, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38879607

RESUMEN

Neurofibromatosis Type II (NFII) is a genetic condition caused by loss of the NF2 gene, resulting in activation of the YAP/TAZ pathway and recurrent Schwann cell tumors, as well as meningiomas and ependymomas. Unfortunately, few pharmacological options are available for NFII. Here, we undertake a genome-wide CRISPR/Cas9 screen to search for synthetic-lethal genes that, when inhibited, cause death of NF2 mutant Schwann cells but not NF2 wildtype cells. We identify ACSL3 and G6PD as two synthetic-lethal partners for NF2, both involved in lipid biogenesis and cellular redox. We find that NF2 mutant Schwann cells are more oxidized than control cells, in part due to reduced expression of genes involved in NADPH generation such as ME1. Since G6PD and ME1 redundantly generate cytosolic NADPH, lack of either one is compatible with cell viability, but not down-regulation of both. Since genetic deficiency for G6PD is tolerated in the human population, G6PD could be a good pharmacological target for NFII.


Asunto(s)
Sistemas CRISPR-Cas , Coenzima A Ligasas , Glucosafosfato Deshidrogenasa , Neurofibromina 2 , Células de Schwann , Mutaciones Letales Sintéticas , Células de Schwann/metabolismo , Humanos , Glucosafosfato Deshidrogenasa/metabolismo , Glucosafosfato Deshidrogenasa/genética , Neurofibromina 2/metabolismo , Neurofibromina 2/genética , Coenzima A Ligasas/metabolismo , Coenzima A Ligasas/genética , Animales , Neurofibromatosis 2/metabolismo , Neurofibromatosis 2/genética , NADP/metabolismo , Ratones , Oxidación-Reducción
9.
Biochem Biophys Res Commun ; 726: 150306, 2024 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-38917634

RESUMEN

The folate metabolism enzyme ALDH1L1 catalyzed 10-formyltetrahydrofolate to tetrahydrofolate and CO2. Non-small cell lung cancer cells (NSCLC) strongly express ALDH1L1. Gossypol binds to an allosteric site and disrupts the folate metabolism by preventing NADP+ binding. The Cryo-EM structures of tetrameric C-terminal aldehyde dehydrogenase human ALDH1L1 complex with gossypol were examined. Gossypol-bound ALDH1L1 interfered with NADP+ by shifting the allosteric site of the structural conformation, producing a closed-form NADP+ binding site. In addition, the inhibition activity of ALDH1L1 was targeted with gossypol in NSCLC. The gossypol treatment had anti-cancer effects on NSCLC by blocking NADPH and ATP production. These findings emphasize the structure characterizing ALDH1L1 with gossypol.


Asunto(s)
Gosipol , Humanos , Gosipol/química , Gosipol/farmacología , Gosipol/metabolismo , NADP/metabolismo , NADP/química , Modelos Moleculares , Microscopía por Crioelectrón , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/patología , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/patología , Aldehído Oxidorreductasas/metabolismo , Aldehído Oxidorreductasas/química , Unión Proteica , Sitios de Unión , Sitio Alostérico , Conformación Proteica , Línea Celular Tumoral , Oxidorreductasas actuantes sobre Donantes de Grupo CH-NH
10.
J Biomed Opt ; 29(Suppl 2): S22709, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38881557

RESUMEN

Significance: To enable non-destructive longitudinal assessment of drug agents in intact tumor tissue without the use of disruptive probes, we have designed a label-free method to quantify the health of individual tumor cells in excised tumor tissue using multiphoton fluorescence lifetime imaging microscopy (MP-FLIM). Aim: Using murine tumor fragments which preserve the native tumor microenvironment, we seek to demonstrate signals generated by the intrinsically fluorescent metabolic co-factors nicotinamide adenine dinucleotide phosphate [NAD(P)H] and flavin adenine dinucleotide (FAD) correlate with irreversible cascades leading to cell death. Approach: We use MP-FLIM of NAD(P)H and FAD on tissues and confirm viability using standard apoptosis and live/dead (Caspase 3/7 and propidium iodide, respectively) assays. Results: Through a statistical approach, reproducible shifts in FLIM data, determined through phasor analysis, are shown to correlate with loss of cell viability. With this, we demonstrate that cell death achieved through either apoptosis/necrosis or necroptosis can be discriminated. In addition, specific responses to common chemotherapeutic treatment inducing cell death were detected. Conclusions: These data demonstrate that MP-FLIM can detect and quantify cell viability without the use of potentially toxic dyes, thus enabling longitudinal multi-day studies assessing the effects of therapeutic agents on tumor fragments.


Asunto(s)
Supervivencia Celular , Microscopía de Fluorescencia por Excitación Multifotónica , Animales , Ratones , Supervivencia Celular/efectos de los fármacos , Microscopía de Fluorescencia por Excitación Multifotónica/métodos , Apoptosis , Flavina-Adenina Dinucleótido/química , NADP/metabolismo , Línea Celular Tumoral , Imagen Óptica/métodos
11.
Brain Res Bull ; 214: 111006, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38852654

RESUMEN

BACKGROUND: Limb remote ischemic postconditioning (LRIP) and paeoniflorin (PF) both can ameliorate cerebral ischemia reperfusion (I/R) injury. At present, whether LRIP combined with PF can achieve better therapeutic effect is unknown. PURPOSE: This study explored the alleviating effect and mechanism of LRIP in combination with PF on cerebral I/R injury in rats. METHODS: Middle cerebral artery occlusion (MCAO) surgery was performed on rats except Sham group. Then PF (2.5 mg/kg, 5 mg/kg, 10 mg/kg) was administrated by intraperitoneal injection 10 min before the start of reperfusion. LRIP was operated on the left femoral artery at 0 h of reperfusion. Behavioral testing was used to assess neurological impairment, while TTC staining was used to examine infarct volume. Protein expression of MyD88, TRAF6, p38-MAPK and phosphorylation of p47phox in neutrophils from rat peripheral blood were tested by Western blot. Rat bone marrow neutrophils were extracted and incubated for 24 h with serum from rats after LRIP combined with PF. p38 MAPK inhibitor group was administrated SB203580 while the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase inhibitor group was administrated Apocynin. Neutrophils were stimulated by fMLP (10 µM). Reactive oxygen species (ROS) production and protein expression of MyD88, TRAF6, p38 MAPK, and p47phox (ser 304 and ser 345) were detected. RESULTS: LRIP combined with PF (5 mg/kg) reduced cerebral infarct volume, ameliorated neurological deficit score (NDS), decreased fMLP-stimulated ROS release and downregulated the protein expression of MyD88, TRAF6, p38-MAPK and phosphorylation of p47phox (ser 304 and ser 345) in neutrophils. CONCLUSION: The protective effect of LRIP combined with PF on cerebral I/R injury was better than either alone. Taken together, we provided solid evidence to demonstrate that the combination of LRIP and PF had potential to alleviate cerebral I/R injury, which was regulated by MyD88-TRAF6-p38 MAPK pathway and neutrophil NADPH oxidase pathway.


Asunto(s)
Isquemia Encefálica , Glucósidos , Poscondicionamiento Isquémico , Monoterpenos , Neutrófilos , Ratas Sprague-Dawley , Daño por Reperfusión , Animales , Neutrófilos/efectos de los fármacos , Neutrófilos/metabolismo , Masculino , Poscondicionamiento Isquémico/métodos , Daño por Reperfusión/metabolismo , Daño por Reperfusión/tratamiento farmacológico , Glucósidos/farmacología , Ratas , Monoterpenos/farmacología , Monoterpenos/uso terapéutico , Isquemia Encefálica/metabolismo , Isquemia Encefálica/tratamiento farmacológico , NADPH Oxidasas/metabolismo , Infarto de la Arteria Cerebral Media , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , NADP/metabolismo , Transducción de Señal/efectos de los fármacos
12.
Int J Mol Sci ; 25(11)2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38892017

RESUMEN

The impact of age on mesenchymal stromal cell (MSC) characteristics has been well researched. However, increased age is concomitant with increased prevalence of polypharmacy. This adjustable factor may have further implications for the functionality of MSCs and the effectiveness of autologous MSC procedures. We applied hyperspectral microscopy of cell autofluorescence-a non-invasive imaging technique used to characterise cytometabolic heterogeneity-to identify changes in the autofluorescence signals of MSCs from (1) young mice, (2) old mice, (3) young mice randomised to receive polypharmacy (9-10 weeks of oral therapeutic doses of simvastatin, metoprolol, oxycodone, oxybutynin and citalopram), and (4) old mice randomised to receive polypharmacy. Principal Component Analysis and Logistic Regression Analysis were used to assess alterations in spectral and associated metabolic characteristics. Modelling demonstrated that cells from young mice receiving polypharmacy had less NAD(P)H and increased porphyrin relative to cells from old control mice, allowing for effective separation of the two groups (AUC of ROC curve > 0.94). Similarly, cells from old polypharmacy mice were accurately separated from those from young controls due to lower levels of NAD(P)H (p < 0.001) and higher porphyrin (p < 0.001), allowing for an extremely accurate logistic regression (AUC of ROC curve = 0.99). This polypharmacy regimen may have a more profound impact on MSCs than ageing, and can simultaneously reduce optical redox ratio (ORR) and increase porphyrin levels. This has implications for the use of autologous MSCs for older patients with chronic disease.


Asunto(s)
Envejecimiento , Células Madre Mesenquimatosas , Polifarmacia , Animales , Células Madre Mesenquimatosas/metabolismo , Células Madre Mesenquimatosas/citología , Ratones , Envejecimiento/metabolismo , Masculino , Imagen Óptica/métodos , NADP/metabolismo
13.
Biosystems ; 242: 105257, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38876357

RESUMEN

This study investigates the metabolic parallels between stimulated pancreatic beta cells and cancer cells, focusing on glucose and glutamine metabolism. Addressing the significant public health challenges of Type 2 Diabetes (T2D) and cancer, we aim to deepen our understanding of the mechanisms driving insulin secretion and cellular proliferation. Our analysis of anaplerotic cycles and the role of NADPH in biosynthesis elucidates their vital functions in both processes. Additionally, we point out that both cell types share an antioxidative response mediated by the Nrf2 signaling pathway, glutathione synthesis, and UCP2 upregulation. Notably, UCP2 facilitates the transfer of C4 metabolites, enhancing reductive TCA cycle metabolism. Furthermore, we observe that hypoxic responses are transient in beta cells post-stimulation but persistent in cancer cells. By synthesizing these insights, the research may suggest novel therapeutic targets for T2D, highlighting the shared metabolic strategies of stimulated beta cells and cancer cells. This comparative analysis not only illuminates the metabolic complexity of these conditions but also emphasizes the crucial role of metabolic pathways in cell function and survival, offering fresh perspectives for tackling T2D and cancer challenges.


Asunto(s)
Diabetes Mellitus Tipo 2 , Glucosa , Células Secretoras de Insulina , Neoplasias , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/fisiología , Humanos , Glucosa/metabolismo , Neoplasias/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Glutamina/metabolismo , Proteína Desacopladora 2/metabolismo , Proteína Desacopladora 2/genética , Factor 2 Relacionado con NF-E2/metabolismo , Animales , Transducción de Señal/fisiología , Proliferación Celular/fisiología , NADP/metabolismo , Insulina/metabolismo , Ciclo del Ácido Cítrico
14.
Biotechnol J ; 19(5): e2400014, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38719614

RESUMEN

Microbial production of L-malic acid from renewable carbon sources has attracted extensive attention. The reduced cofactor NADPH plays a key role in biotransformation because it participates in both biosynthetic reactions and cellular stress responses. In this study, NADPH or its precursors nicotinamide and nicotinic acid were added to the fermentation medium of Aspergillus niger RG0095, which significantly increased the yield of malic acid by 11%. To further improve the titer and productivity of L-malic acid, we increased the cytoplasmic NADPH levels of A. niger by upregulating the NAD kinases Utr1p and Yef1p. Biochemical analyses demonstrated that overexpression of Utr1p and Yef1p reduced oxidative stress, while also providing more NADPH to catalyze the conversion of glucose into malic acid. Notably, the strain overexpressing Utr1p reached a malate titer of 110.72 ± 1.91 g L-1 after 108 h, corresponding to a productivity of 1.03 ± 0.02 g L-1 h-1. Thus, the titer and productivity of malate were increased by 24.5% and 44.7%, respectively. The strategies developed in this study may also be useful for the metabolic engineering of fungi to produce other industrially relevant bulk chemicals.


Asunto(s)
Aspergillus niger , Fermentación , Malatos , Ingeniería Metabólica , NADP , Aspergillus niger/metabolismo , Aspergillus niger/genética , Malatos/metabolismo , Ingeniería Metabólica/métodos , NADP/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Glucosa/metabolismo , Fosfotransferasas (Aceptor de Grupo Alcohol)/genética , Fosfotransferasas (Aceptor de Grupo Alcohol)/metabolismo
15.
Nat Commun ; 15(1): 4083, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38744825

RESUMEN

Energetic stress compels cells to evolve adaptive mechanisms to adjust their metabolism. Inhibition of mTOR kinase complex 1 (mTORC1) is essential for cell survival during glucose starvation. How mTORC1 controls cell viability during glucose starvation is not well understood. Here we show that the mTORC1 effectors eukaryotic initiation factor 4E binding proteins 1/2 (4EBP1/2) confer protection to mammalian cells and budding yeast under glucose starvation. Mechanistically, 4EBP1/2 promote NADPH homeostasis by preventing NADPH-consuming fatty acid synthesis via translational repression of Acetyl-CoA Carboxylase 1 (ACC1), thereby mitigating oxidative stress. This has important relevance for cancer, as oncogene-transformed cells and glioma cells exploit the 4EBP1/2 regulation of ACC1 expression and redox balance to combat energetic stress, thereby supporting transformation and tumorigenicity in vitro and in vivo. Clinically, high EIF4EBP1 expression is associated with poor outcomes in several cancer types. Our data reveal that the mTORC1-4EBP1/2 axis provokes a metabolic switch essential for survival during glucose starvation which is exploited by transformed and tumor cells.


Asunto(s)
Acetil-CoA Carboxilasa , Proteínas Adaptadoras Transductoras de Señales , Proteínas de Ciclo Celular , Supervivencia Celular , Ácidos Grasos , Glucosa , Diana Mecanicista del Complejo 1 de la Rapamicina , Animales , Humanos , Ratones , Acetil-CoA Carboxilasa/metabolismo , Acetil-CoA Carboxilasa/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/genética , Línea Celular Tumoral , Factores Eucarióticos de Iniciación/metabolismo , Factores Eucarióticos de Iniciación/genética , Ácidos Grasos/metabolismo , Glucosa/metabolismo , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Diana Mecanicista del Complejo 1 de la Rapamicina/genética , NADP/metabolismo , Estrés Oxidativo , Fosfoproteínas/metabolismo , Fosfoproteínas/genética , Biosíntesis de Proteínas
16.
Nat Commun ; 15(1): 3994, 2024 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-38734761

RESUMEN

NADPH oxidase 5 (NOX5) catalyzes the production of superoxide free radicals and regulates physiological processes from sperm motility to cardiac rhythm. Overexpression of NOX5 leads to cancers, diabetes, and cardiovascular diseases. NOX5 is activated by intracellular calcium signaling, but the underlying molecular mechanism of which - in particular, how calcium triggers electron transfer from NADPH to FAD - is still unclear. Here we capture motions of full-length human NOX5 upon calcium binding using single-particle cryogenic electron microscopy (cryo-EM). By combining biochemistry, mutagenesis analyses, and molecular dynamics (MD) simulations, we decode the molecular basis of NOX5 activation and electron transfer. We find that calcium binding to the EF-hand domain increases NADPH dynamics, permitting electron transfer between NADPH and FAD and superoxide production. Our structural findings also uncover a zinc-binding motif that is important for NOX5 stability and enzymatic activity, revealing modulation mechanisms of reactive oxygen species (ROS) production.


Asunto(s)
Calcio , NADPH Oxidasa 5 , NADP , Humanos , Sitios de Unión , Calcio/metabolismo , Microscopía por Crioelectrón , Transporte de Electrón , Activación Enzimática , Flavina-Adenina Dinucleótido/metabolismo , Simulación de Dinámica Molecular , NADP/metabolismo , NADPH Oxidasa 5/metabolismo , NADPH Oxidasa 5/genética , NADPH Oxidasa 5/química , Unión Proteica , Especies Reactivas de Oxígeno/metabolismo , Superóxidos/metabolismo , Zinc/metabolismo
17.
Bioessays ; 46(7): e2400073, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38760877

RESUMEN

Sterols and the reductant nicotinamide adenine dinucleotide phosphate (NADPH), essential for eukaryotic life, arose because of, and as an adaptation to, rising levels of molecular oxygen (O2). Hence, the NADPH and O2-intensive process of sterol biosynthesis is inextricably linked to redox status. In mammals, cholesterol biosynthesis is exquisitely regulated post-translationally by multiple E3 ubiquitin ligases, with membrane associated Really Interesting New Gene (RING) C3HC4 finger 6 (MARCHF6) degrading at least six enzymes in the pathway. Intriguingly, all these MARCHF6-dependent enzymes require NADPH. Moreover, MARCHF6 is activated by NADPH, although what this means for control of cholesterol synthesis is unclear. Indeed, this presents a paradox for how NADPH regulates this vital pathway, since NADPH is a cofactor in cholesterol biosynthesis and yet, low levels of NADPH should spare cholesterol biosynthesis enzymes targeted by MARCHF6 by reducing its activity. We speculate MARCHF6 helps mammalian cells adapt to oxidative stress (signified by low NADPH levels) by reducing degradation of cholesterogenic enzymes, thereby maintaining synthesis of protective cholesterol.


Asunto(s)
Colesterol , NADP , Estrés Oxidativo , Ubiquitina-Proteína Ligasas , NADP/metabolismo , Colesterol/biosíntesis , Colesterol/metabolismo , Humanos , Animales , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitina-Proteína Ligasas/genética , Proteínas de la Membrana/metabolismo , Proteínas de la Membrana/genética , Oxidación-Reducción , Esteroles/metabolismo , Esteroles/biosíntesis
18.
Chembiochem ; 25(14): e202400350, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38775737

RESUMEN

CreE is a flavin-dependent monooxygenase (FMO) that catalyzes three sequential nitrogen oxidation reactions of L-aspartate to produce nitrosuccinate, contributing to the biosynthesis of the antimicrobial and antiproliferative nautral product, cremeomycin. This compound contains a highly reactive diazo functional group for which the reaction of CreE is essential to its formation. Nitro and diazo functional groups can serve as potent electrophiles, important in some challenging nucleophilic addition reactions. Formation of these reactive groups positions CreE as a promising candidate for biomedical and synthetic applications. Here, we present the catalytic mechanism of CreE and the identification of active site residues critical to binding L-aspartate, aiding in future enzyme engineering efforts. Steady-state analysis demonstrated that CreE is very specific for NADPH over NADH and performs a highly coupled reaction with L-aspartate. Analysis of the rapid-reaction kinetics showed that flavin reduction is very fast, along with the formation of the oxygenating species, the C4a-hydroperoxyflavin. The slowest step observed was the dehydration of the flavin. Structural analysis and site-directed mutagenesis implicated T65, R291, and R440 in the binding L-aspartate. The data presented describes the catalytic mechanism and the active site architecture of this unique FMO.


Asunto(s)
Ácido Aspártico , Dominio Catalítico , Oxigenasas de Función Mixta , Cinética , Oxigenasas de Función Mixta/metabolismo , Oxigenasas de Función Mixta/química , Oxigenasas de Función Mixta/genética , Ácido Aspártico/química , Ácido Aspártico/metabolismo , Biocatálisis , Oxidación-Reducción , NADP/metabolismo , NADP/química , Mutagénesis Sitio-Dirigida
19.
Redox Biol ; 73: 103176, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38705094

RESUMEN

Excitotoxicity is a prevalent pathological event in neurodegenerative diseases. The involvement of ferroptosis in the pathogenesis of excitotoxicity remains elusive. Transcriptome analysis has revealed that cytoplasmic reduced nicotinamide adenine dinucleotide phosphate (NADPH) levels are associated with susceptibility to ferroptosis-inducing compounds. Here we show that exogenous NADPH, besides being reductant, interacts with N-myristoyltransferase 2 (NMT2) and upregulates the N-myristoylated ferroptosis suppressor protein 1 (FSP1). NADPH increases membrane-localized FSP1 and strengthens resistance to ferroptosis. Arg-291 of NMT2 is critical for the NADPH-NMT2-FSP1 axis-mediated suppression of ferroptosis. This study suggests that NMT2 plays a pivotal role by bridging NADPH levels and neuronal susceptibility to ferroptosis. We propose a mechanism by which the NADPH regulates N-myristoylation, which has important implications for ferroptosis and disease treatment.


Asunto(s)
Ferroptosis , NADP , Humanos , NADP/metabolismo , Animales , Aciltransferasas/metabolismo , Aciltransferasas/genética , Ratones , Procesamiento Proteico-Postraduccional
20.
ACS Synth Biol ; 13(6): 1798-1808, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38748665

RESUMEN

Betulinic acid (BA) is a lupane-type triterpenoid with potent anticancer and anti-HIV activities. Its great potential in clinical applications necessitates the development of an efficient strategy for BA synthesis. This study attempted to achieve efficient BA biosynthesis in Saccharomyces cerevisiae using systematic metabolic engineering strategies. First, a de novo BA biosynthesis pathway in S. cerevisiae was constructed, which yielded a titer of 14.01 ± 0.21 mg/L. Then, by enhancing the BA synthesis pathway and dynamic inhibition of the competitive pathway, a greater proportion of the metabolic flow was directed toward BA synthesis, achieving a titer of 88.07 ± 5.83 mg/L. Next, acetyl-CoA and NADPH supply was enhanced, which increased the BA titer to 166.43 ± 1.83 mg/L. Finally, another BA synthesis pathway in the peroxisome was constructed. Dual regulation of the peroxisome and cytoplasmic metabolism increased the BA titer to 210.88 ± 4.76 mg/L. Following fed-batch fermentation process modification, the BA titer reached 682.29 ± 8.16 mg/L. Overall, this work offers a guide for building microbial cell factories that are capable of producing terpenoids with efficiency.


Asunto(s)
Ácido Betulínico , Ingeniería Metabólica , NADP , Triterpenos Pentacíclicos , Saccharomyces cerevisiae , Triterpenos , Ingeniería Metabólica/métodos , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Triterpenos Pentacíclicos/metabolismo , Triterpenos/metabolismo , NADP/metabolismo , Acetilcoenzima A/metabolismo , Fermentación , Vías Biosintéticas/genética
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