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1.
Bioresour Technol ; 413: 131446, 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-39241814

RESUMEN

Cordycepin, a nucleoside analog, is widely used in medicine and health products. However, the production of cordycepin from Cordyceps militaris faces the challenges of low productivity and high rate of greenhouse gas emissions. In this study, by optimizing the cordycepin biosynthesis pathway through promoter combination, Kozak sequence, and enzyme fusion, enhancing the methanol assimilation capacity in peroxisomes, adjusting the synthesis of NADPH and ATP, and combining the enhanced supply of adenosine and 3'-AMP, the cordycepin high-yield strain Pp29 was constructed, which produced 1551.44 mg/L cordycepin by shake-flask fermentation. In fed-batch fermentation, Pp29 achieved the highest yield (8.11 g/L, 67.64 mg/g DCW, and 1.35 g/L/d) to date in 10 L fermenter, and the CO2-eq emissions were 1.9-17.3 times lower than C. militaris and other yeast systems. This study provide basis for Pichia pastoris to be used as chassis cell for synthesizing cordycepin and other nucleoside analogs by methanol as carbon source.

2.
Food Microbiol ; 124: 104624, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-39244375

RESUMEN

Environmental conditions significantly impact the metabolism of Saccharomyces cerevisiae, a Crabtree-positive yeast that maintains a fermentative metabolism in high-sugar environments even in the presence of oxygen. Although the introduction of oxygen has been reported to induce alterations in yeast metabolism, knowledge of the mechanisms behind these metabolic adaptations in relation to redox cofactor metabolism and their implications in the context of wine fermentation remains limited. This study aimed to compare the intracellular redox cofactor levels, the cofactor ratios, and primary metabolite production in S. cerevisiae under aerobic and anaerobic conditions in synthetic grape juice. The molecular mechanisms underlying these metabolic differences were explored using a transcriptomic approach. Aerobic conditions resulted in an enhanced fermentation rate and biomass yield. Total NADP(H) levels were threefold higher during aerobiosis, while a decline in the total levels of NAD(H) was observed. However, there were stark differences in the ratio of NAD+/NADH between the treatments. Despite few changes in the differential expression of genes involved in redox cofactor metabolism, anaerobiosis resulted in an increased expression of genes involved in lipid biosynthesis pathways, while the presence of oxygen increased the expression of genes associated with thiamine, methionine, and sulfur metabolism. The production of fermentation by-products was linked with differences in the redox metabolism in each treatment. This study provides valuable insights that may help steer the production of metabolites of industrial interest during alcoholic fermentation (including winemaking) by using oxygen as a lever of redox metabolism.


Asunto(s)
Fermentación , Oxidación-Reducción , Oxígeno , Saccharomyces cerevisiae , Vino , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crecimiento & desarrollo , Oxígeno/metabolismo , Vino/microbiología , Vino/análisis , Anaerobiosis , Vitis/microbiología , Vitis/metabolismo , NAD/metabolismo , Etanol/metabolismo , NADP/metabolismo , Aerobiosis , Regulación Fúngica de la Expresión Génica , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Coenzimas/metabolismo
3.
Comput Struct Biotechnol J ; 23: 3143-3154, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-39234301

RESUMEN

The zinc-finger antiviral protein (ZAP) is an innate immunity sensor of non-self nucleic acids. Its antiviral activity is exerted through the physical interaction with different cofactors, including TRIM25, Riplet and KHNYN. Cellular proteins that interact with infectious agents are expected to be engaged in genetic conflicts that often result in their rapid evolution. To test this possibility and to identify the regions most strongly targeted by natural selection, we applied in silico molecular evolution tools to analyze the evolutionary history of ZAP and cofactors in four mammalian groups. We report evidence of positive selection in all genes and in most mammalian groups. On average, the intrinsically disordered regions (IDRs) embedded in the four proteins evolve significantly faster than folded domains and most positively selected sites fall within IDRs. In ZAP, the PARP domain also shows abundant signals of selection, and independent evolution in different mammalian groups suggests modulation of its ADP-ribose binding ability. Detailed analyses of the biophysical properties of IDRs revealed that chain compaction and conformational entropy are conserved across mammals. The IDRs in ZAP and KHNYN are particularly compact, indicating that they may promote phase separation (PS). In line with this hypothesis, we predicted several PS-promoting regions in ZAP and KHNYN, as well as in TRIM25. Positively selected sites are abundant in these regions, suggesting that PS may be important for the antiviral functions of these proteins and the evolutionary arms race with viruses. Our data shed light into the evolution of ZAP and cofactors and indicate that IDRs represent central elements in host-pathogen interactions.

4.
Biomolecules ; 14(8)2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-39199293

RESUMEN

Lithium is one of the lightest elements on Earth and it has been in the environment since the formation of the galaxy. While a common element, it has not been found to be an essential element in biological processes, ranging from single cell organisms to Homo sapiens. Instead, at an early stage of evolution, organisms committed to a range of elements such as sodium, potassium, calcium, magnesium, zinc, and iron to serve essential functions. Such ions serve critical functions in ion channels, as co-factors in enzymes, as a cofactor in oxygen transport, in DNA replication, as a storage molecule in bone and liver, and in a variety of other roles in biological processes. While seemingly excluded from a major essential role in such processes, lithium ions appear to be able to modulate a variety of biological processes and "correct" deviation from normal activity, as a deficiency of lithium can have biological consequences. Lithium salts are found in low levels in many foods and water supplies, but the effectiveness of Li salts to affect biological systems came to recent prominence with the work of Cade, who reported that administrating Li salts calmed guinea pigs and was subsequently effective at relatively high doses to "normalize" a subset of patients with bipolar disorders. Because of its ability to modulate many biological pathways and processes (e.g., cyclic AMP, GSK-3beta, inositol metabolism, NaK ATPases, neuro processes and centers, immune-related events, respectively) both in vitro and in vivo and during development and adult life, Li salts have become both a useful tool to better understand the molecular regulation of such processes and to also provide insights into altered biological processes in vivo during aging and in disease states. While the range of targets for lithium action supports its possible role as a modulator of biological dysregulation, it presents a conundrum for researchers attempting to elucidate its specific primary target in different tissues in vivo. This review will discuss aspects of the state of knowledge regarding some of the systems that can be influenced, focusing on those involving neural and autoimmunity as examples, some of the mechanisms involved, examples of how Li salts can be used to study model systems, as well as suggesting areas where the use of Li salts could lead to additional insights into both disease mechanisms and natural processes at the molecular and cell levels. In addition, caveats regarding lithium doses used, the strengths and weaknesses of rodent models, the background genetics of the strain of mice or rats employed, and the sex of the animals or the cells used, are discussed. Low-dose lithium may have excellent potential, alone or in combination with other interventions to prevent or alleviate aging-associated conditions and disease progression.


Asunto(s)
Envejecimiento , Litio , Humanos , Animales , Envejecimiento/efectos de los fármacos , Envejecimiento/metabolismo , Litio/farmacología
5.
Trends Biotechnol ; 2024 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-39214790

RESUMEN

One-pot enzymatic synthesis is flourishing in synthetic chemistry, heralding a sustainable and green era. Recent advancements enable the creation of complex enzymatic prosthetic groups and regeneration of enzymatic cofactors such as S-adenosylmethionine. The next frontier is to develop the effective and innovative cofactors for essential micronutrients, metabolic modulators, and biomedicines.

6.
Nano Lett ; 24(32): 9974-9982, 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39083237

RESUMEN

Various applications related to glucose catalysis have led to the development of functional nanozymes with glucose oxidase (GOX)-like activity. However, the unsatisfactory catalytic activity of nanozymes is a major challenge for their practical applications due to their inefficient hydrogen and electron transfer. Herein, we present the synthesis of AuFe/polydopamine (PDA) superparticles that exhibit photothermal-enhanced GOX-like activity. Experimental investigations and theoretical calculations reveal that the glucose oxidation process catalyzed by AuFe/PDA follows an artificial-cofactor-mediated hydrogen atom transfer mechanism, which facilitates the generation of carbon-centered radical intermediates. Rather than depending on charged Au surfaces for thermodynamically unstable hydride transfer, Fe(III)-coordinated PDA with abundant amino and phenolic hydroxyl groups serves as cofactor mimics, facilitating both hydrogen atom and electron transfer in the catalytic process. Finally, leveraging the photothermal-enhanced GOX-like and catalase-like activities of AuFe/PDA, we establish a highly sensitive and accurate point-of-care testing blood glucose determination with exceptional anti-jamming capabilities.


Asunto(s)
Glucosa Oxidasa , Oro , Hidrógeno , Indoles , Polímeros , Glucosa Oxidasa/química , Glucosa Oxidasa/metabolismo , Oro/química , Hidrógeno/química , Transporte de Electrón , Indoles/química , Polímeros/química , Glucosa/química , Catálisis , Oxidación-Reducción , Glucemia/análisis , Hierro/química , Humanos
7.
Biochim Biophys Acta Mol Cell Res ; 1871(7): 119794, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39033933

RESUMEN

Sulfur-containing biomolecules such as [FeS] clusters, thiamin, biotin, molybdenum cofactor, and sulfur-containing tRNA nucleosides are essential for various biochemical reactions. The amino acid l-cysteine serves as the major sulfur source for the biosynthetic pathways of these sulfur-containing cofactors in prokaryotic and eukaryotic systems. The first reaction in the sulfur mobilization involves a class of pyridoxal-5'-phosphate (PLP) dependent enzymes catalyzing a Cys:sulfur acceptor sulfurtransferase reaction. The first half of the catalytic reaction involves a PLP-dependent CS bond cleavage, resulting in a persulfide enzyme intermediate. The second half of the reaction involves the subsequent transfer of the thiol group to a specific acceptor molecule, which is responsible for the physiological role of the enzyme. Structural and biochemical analysis of these Cys sulfurtransferase enzymes shows that specific protein-protein interactions with sulfur acceptors modulate their catalytic reactivity and restrict their biochemical functions.


Asunto(s)
Cisteína , Fosfato de Piridoxal , Azufre , Sulfurtransferasas , Azufre/metabolismo , Azufre/química , Cisteína/metabolismo , Cisteína/química , Sulfurtransferasas/metabolismo , Sulfurtransferasas/química , Fosfato de Piridoxal/metabolismo , Humanos , Cofactores de Molibdeno , Liasas de Carbono-Azufre/metabolismo , Liasas de Carbono-Azufre/química
8.
Appl Environ Microbiol ; 90(8): e0085024, 2024 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-39016614

RESUMEN

Viral communities exist in a variety of ecosystems and play significant roles in mediating biogeochemical processes, whereas viruses inhabiting strongly alkaline geochemical systems remain underexplored. In this study, the viral diversity, potential functionalities, and virus-host interactions in a strongly alkaline environment (pH = 10.4-12.4) exposed to the leachates derived from the serpentinization-like reactions of smelting slags were investigated. The viral populations (e.g., Herelleviridae, Queuovirinae, and Inoviridae) were closely associated with the dominating prokaryotic hosts (e.g., Meiothermus, Trueperaceae, and Serpentinomonas) in this ultrabasic environment. Auxiliary metabolic genes (AMGs) suggested that viruses may enhance hosts' fitness by facilitating cofactor biosynthesis, hydrogen metabolism, and carbon cycling. To evaluate the activity of synthesis of essential cofactor vitamin B9 by the viruses, a viral folA (vfolA) gene encoding dihydrofolate reductase (DHFR) was introduced into a thymidine-auxotrophic strain Escherichia coli MG1655 ΔfolA mutant, which restored the growth of the latter in the absence of thymidine. Notably, the homologs of the validated vDHFR were globally distributed in the viromes across various ecosystems. The present study sheds new light on the unique viral communities in hyperalkaline ecosystems and their potential beneficial impacts on the coexisting microbial consortia by supplying essential cofactors. IMPORTANCE: This study presents a comprehensive investigation into the diversity, potential functionalities, and virus-microbe interactions in an artificially induced strongly alkaline environment. Functional validation of the detected viral folA genes encoding dihydrofolate reductase substantiated the synthesis of essential cofactors by viruses, which may be ubiquitous, considering the broad distribution of the viral genes associated with folate cycling.


Asunto(s)
Microbiota , Concentración de Iones de Hidrógeno , Viroma/genética , Virus/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Tetrahidrofolato Deshidrogenasa/genética , Tetrahidrofolato Deshidrogenasa/metabolismo , Bacterias/genética , Bacterias/metabolismo , Bacterias/clasificación
9.
Curr Opin Chem Biol ; 81: 102504, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39068821

RESUMEN

[4 + 2] Cyclases are potent biocatalysts that have been bestowed upon microorganisms and plants by nature, equipping them with the powerful tools to utilize and implement the [4 + 2] cycloaddition reaction for constructing the cyclohexene core in synthesizing valuable molecules. Over the past two years, eleven new enzymes have joined this pericyclase club and undergone extensive investigation. In this review, we present a comprehensive overview of recent advancements in characterizing [4 + 2] cyclases with regard to their catalytic mechanism and stereoselectivity. We particularly focus on insights gained from enzyme co-crystal structures, cofactors, as well as the effects of glycosylation. Advancements in understanding the mechanisms of natural [4 + 2] cyclases offer the potential to mimic evolutionary processes and engineer artificial enzymes for the development of valuable and practical biocatalysts.


Asunto(s)
Evolución Molecular , Estereoisomerismo , Biocatálisis , Glicosilación , Reacción de Cicloadición
10.
Int J Mol Sci ; 25(14)2024 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-39063190

RESUMEN

As a critical step in advancing the simulation of photosynthetic complexes, we present the Martini 3 coarse-grained (CG) models of key cofactors associated with light harvesting (LHCII) proteins and the photosystem II (PSII) core complex. Our work focuses on the parametrization of beta-carotene, plastoquinone/quinol, violaxanthin, lutein, neoxanthin, chlorophyll A, chlorophyll B, and heme. We derived the CG parameters to match the all-atom reference simulations, while structural and thermodynamic properties of the cofactors were compared to experimental values when available. To further assess the reliability of the parameterization, we tested the behavior of these cofactors within their physiological environments, specifically in a lipid bilayer and bound to photosynthetic complexes. The results demonstrate that our CG models maintain the essential features required for realistic simulations. This work lays the groundwork for detailed simulations of the PSII-LHCII super-complex, providing a robust parameter set for future studies.


Asunto(s)
Complejos de Proteína Captadores de Luz , Simulación de Dinámica Molecular , Fotosíntesis , Complejo de Proteína del Fotosistema II , Complejo de Proteína del Fotosistema II/metabolismo , Complejo de Proteína del Fotosistema II/química , Complejos de Proteína Captadores de Luz/química , Complejos de Proteína Captadores de Luz/metabolismo , Clorofila/metabolismo , Clorofila/química , Termodinámica , beta Caroteno/química , beta Caroteno/metabolismo , Membrana Dobles de Lípidos/química , Membrana Dobles de Lípidos/metabolismo , Hemo/química , Hemo/metabolismo , Clorofila A/química , Clorofila A/metabolismo
11.
Cancer Rep (Hoboken) ; 7(6): e2124, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-39031901

RESUMEN

BACKGROUND: The major burden of cervical cancer occurs in low- and middle-income countries. In Ghana, it is the second most common cancer among women. Infection with high-risk human papilloma virus (HPV) has been established as the cause of cervical cancer. As such, it is important to identify risk factors that may affect progression from HPV infection to cancer. AIMS: We assessed the risk factors assocaited with cervical cancer in Ghana. METHODS: To identify the risk factors for cervical cancer, we conducted an unmatched case-control study in two hospitals in Ghana where most cervical cancer cases are diagnosed. Women with histologically confirmed cervical cancer were the cases, whereas women without cancer seeking care at the two hospitals were controls. A structured questionnaire was administered to the women, after which cervical samples were sent for HPV deoxyribonucleic acid (DNA) testing. RESULTS: Overall, 206 cases and 230 controls were recruited. After adjusting for possible confounders, women with the highest educational level had a significantly lower risk of cervical cancer than those with no or little formal education. Parity was a major risk factor (odd ratio [OR] for five or more children = 7.9; 95% CI: 2.3-27.6), with risk increasing with increasing parity (p for trend <0.001). Women reporting the use of a homemade sanitary towel during menstruation also had an increased risk of cervical cancer compared with women who used a pad (OR: 7.3; 95% CI: 2.5-22.0). CONCLUSION: In this Ghanaian population, high parity and poor personal hygienic conditions were the main contributing factors to the risk of cervical cancer after adjustment for the presence of high-risk HPV genotypes.


Asunto(s)
Infecciones por Papillomavirus , Neoplasias del Cuello Uterino , Humanos , Femenino , Ghana/epidemiología , Neoplasias del Cuello Uterino/virología , Neoplasias del Cuello Uterino/epidemiología , Neoplasias del Cuello Uterino/diagnóstico , Estudios de Casos y Controles , Factores de Riesgo , Adulto , Infecciones por Papillomavirus/epidemiología , Infecciones por Papillomavirus/complicaciones , Infecciones por Papillomavirus/virología , Persona de Mediana Edad , Paridad , Adulto Joven , Papillomaviridae/aislamiento & purificación , Embarazo , Encuestas y Cuestionarios , Anciano
12.
Methods Mol Biol ; 2839: 53-75, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39008248

RESUMEN

Iron forms essential cofactors used by many nuclear enzymes involved in genome maintenance. However, unchaperoned nuclear iron may represent a threat to the surrounding genetic material as it promotes redox toxicity that may affect DNA integrity. Safely handling intracellular iron implies metal transfer and cofactor assembly processes based on protein-protein interactions. Identifying those interactions commonly occurs via high-throughput approaches using affinity purification or proximity labeling coupled with mass spectrometry analysis. However, these methods do not identify the subcellular location of the interactions. The one-on-one confirmation of proposed nuclear interactions is also challenging. Many approaches used to look at protein interactions are not tailored for looking at the nucleus because the methods used to solubilize nuclear content are harsh enough to disrupt those transient interactions. Here, we describe step-by-step the use of Proximity Ligation Assay (PLA) to analyze iron-mediated protein-protein interactions in the nucleus of cultured human cells. PLA allows the subcellular visualization of the interactions via the in situ detection of the two interacting proteins using fluorescence confocal microscopy. Briefly, cells are fixed, blocked, permeabilized, and incubated with primary antibodies directed to target proteins. Primary antibodies are recognized using PLA probes consisting of one PLUS and one MINUS oligonucleotide-labeled secondary antibody. If the two proteins are close enough (<40 nm), the PLA probes are ligated and used as the template for rolling circle amplification (RCA) with fluorescently labeled oligonucleotides that yield a signal detectable using fluorescence confocal microscopy. A fluorescently labeled membrane-specific stain (WGA) and the DNA-specific probe DAPI are used to identify cellular and nuclear boundaries, respectively. Confocal images are then analyzed using the CellProfiler software to confirm the abundance and localization of the studied protein-protein interactions.


Asunto(s)
Núcleo Celular , Hierro , Mapeo de Interacción de Proteínas , Humanos , Núcleo Celular/metabolismo , Hierro/metabolismo , Mapeo de Interacción de Proteínas/métodos , Unión Proteica , Microscopía Confocal/métodos , Microscopía Fluorescente/métodos
13.
Horm Behav ; 164: 105576, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38852479

RESUMEN

Sexually dimorphic behaviors are often regulated by gonadal steroid hormones. Species diversity in behavioral sex differences may arise as expression of genes mediating steroid action in brain regions controlling these behaviors evolves. The electric communication signals of apteronotid knifefishes are an excellent model for comparatively studying neuroendocrine regulation of sexually dimorphic behavior. These fish produce and detect weak electric organ discharges (EODs) for electrolocation and communication. EOD frequency (EODf), controlled by the medullary pacemaker nucleus (Pn), is sexually dimorphic and regulated by androgens and estrogens in some species, but is sexually monomorphic and unaffected by hormones in other species. We quantified expression of genes for steroid receptors, metabolizing enzymes, and cofactors in the Pn of two species with sexually dimorphic EODf (Apteronotus albifrons and Apteronotus leptorhynchus) and two species with sexually monomorphic EODf ("Apteronotus" bonapartii and Parapteronotus hasemani). The "A." bonapartii Pn expressed lower levels of androgen receptor (AR) genes than the Pn of species with sexually dimorphic EODf. In contrast, the P. hasemani Pn robustly expressed AR genes, but expressed lower levels of genes for 5α-reductases, which convert androgens to more potent metabolites, and higher levels of genes for 17ß-hydroxysteroid dehydrogenases that oxidize androgens and estrogens to less potent forms. These findings suggest that sexual monomorphism of EODf arose convergently via two different mechanisms. In "A." bonapartii, reduced Pn expression of ARs likely results in insensitivity of EODf to androgens, whereas in P. hasemani, gonadal steroids may be metabolically inactivated in the Pn, reducing their potential to influence EODf.


Asunto(s)
Comunicación Animal , Pez Eléctrico , Órgano Eléctrico , Caracteres Sexuales , Especificidad de la Especie , Animales , Masculino , Pez Eléctrico/genética , Pez Eléctrico/fisiología , Femenino , Órgano Eléctrico/fisiología , Órgano Eléctrico/metabolismo , Hormonas Esteroides Gonadales/metabolismo , Receptores Androgénicos/genética , Receptores Androgénicos/metabolismo , Expresión Génica/fisiología , Regulación de la Expresión Génica/fisiología
14.
Res Sq ; 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38826306

RESUMEN

Background: Neurodegenerative tauopathies may progress based on seeding by pathological tau assemblies, whereby an aggregate is released from one cell, gains entry to an adjacent or connected cell, and serves as a specific template for its own replication in the cytoplasm. In vitro seeding reactions typically take days, yet seeding into the complex cytoplasmic milieu happens within hours, implicating a machinery with unknown players that controls this process in the acute phase. Methods: We used proximity labeling to identify factors that control seed amplification within 5h of seed exposure. We fused split-APEX2 to the C-terminus of tau repeat domain (RD) to reconstitute peroxidase activity 5h after seeded intracellular tau aggregation. Valosin containing protein (VCP/p97) was the top hit. VCP harbors dominant mutations that underlie two neurodegenerative diseases, multisystem proteinopathy and vacuolar tauopathy, but its mechanistic role is unclear. We used immortalized cells and human neurons to study the effects of VCP on tau seeding. We exposed cells to fibrils or brain homogenates in cell culture media and measured effects on uptake and induction of intracellular tau aggregation following various genetic and chemical manipulations of VCP. Results: VCP knockdown reduced tau seeding. Chemical inhibitors had opposing effects on aggregation in HEK293T tau biosensor cells and human neurons alike: ML-240 increased seeding efficiency, whereas NMS-873 decreased it. The inhibitors were effective only when administered within 8h of seed exposure, indicating a role for VCP early in seed processing. We screened 30 VCP co-factors in HEK293T biosensor cells by genetic knockout or knockdown. Reduction of ATXN3, NSFL1C, UBE4B, NGLY1, and OTUB1 decreased tau seeding, as did NPLOC4, which also uniquely increased soluble tau levels. By contrast, reduction of FAF2 increased tau seeding. Conclusions: Divergent effects on tau seeding of chemical inhibitors and cofactor reduction indicate that VCP regulates this process. This is consistent with a dedicated cytoplasmic processing complex based on VCP that directs seeds acutely towards degradation vs. amplification.

15.
DNA Repair (Amst) ; 139: 103691, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38744091

RESUMEN

The ATP-dependent molecular chaperone Cdc48 (in yeast) and its human counterpart p97 (also known as VCP), are essential for a variety of cellular processes, including the removal of DNA-protein crosslinks (DPCs) from the DNA. Growing evidence demonstrates in the last years that Cdc48/p97 is pivotal in targeting ubiquitinated and SUMOylated substrates on chromatin, thereby supporting the DNA damage response. Along with its cofactors, notably Ufd1-Npl4, Cdc48/p97 has emerged as a central player in the unfolding and processing of DPCs. This review introduces the detailed structure, mechanism and cellular functions of Cdc48/p97 with an emphasis on the current knowledge of DNA-protein crosslink repair pathways across several organisms. The review concludes by discussing the potential therapeutic relevance of targeting p97 in DPC repair.


Asunto(s)
Reparación del ADN , Proteínas de Saccharomyces cerevisiae , Proteína que Contiene Valosina , Proteína que Contiene Valosina/metabolismo , Humanos , Proteínas de Saccharomyces cerevisiae/metabolismo , ADN/metabolismo , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Daño del ADN , Proteínas de Ciclo Celular/metabolismo , Proteínas Nucleares/metabolismo , Adenosina Trifosfatasas/metabolismo , Proteínas de Unión al ADN/metabolismo , Animales , Péptidos y Proteínas de Señalización Intracelular
16.
ChemistryOpen ; 13(8): e202400064, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38607952

RESUMEN

The direct electrochemical reduction of nicotinamide adenine dinucleotide (NAD+) results in various products, complicating the regeneration of the crucial 1,4-NADH cofactor for enzymatic reactions. Previous research primarily focused on steady-state polarization to examine potential impacts on product selectivity. However, this study explores the influence of dynamic conditions on the selectivity of NAD+ reduction products by comparing two dynamic profiles with steady-state conditions. Our findings reveal that the main products, including 1,4-NADH, several dimers, and ADP-ribose, remained consistent across all conditions. A minor by-product, 1,6-NADH, was also identified. The product distribution varied depending on the experimental conditions (steady state vs. dynamic) and the concentration of NAD+, with higher concentrations and overpotentials promoting dimerization. The optimal yield of 1,4-NADH was achieved under steady-state conditions with low overpotential and NAD+ concentrations. While dynamic conditions enhanced the 1,4-NADH yield at shorter reaction times, they also resulted in a significant amount of unidentified products. Furthermore, this study assessed the potential of using pulsed electrochemical regeneration of 1,4-NADH with enoate reductase (XenB) for cyclohexenone reduction.


Asunto(s)
Técnicas Electroquímicas , NAD , Oxidación-Reducción , NAD/química , NAD/metabolismo
17.
FEMS Yeast Res ; 242024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-38637306

RESUMEN

Anaerobic alcoholic fermentation, particularly in high-sugar environments, presents metabolic challenges for yeasts. Crabtree-positive yeasts, including Saccharomyces cerevisiae, prefer fermentation even in the presence of oxygen. These yeasts rely on internal NAD+ recycling and extracellular assimilation of its precursor, nicotinic acid (vitamin B3), rather than de novo NAD+ production. Surprisingly, nicotinic acid assimilation is poorly characterized, even in S. cerevisiae. This study elucidated the timing of nicotinic acid uptake during grape juice-like fermentation and its impact on NAD(H) levels, the NAD+/NADH ratio, and metabolites produced. Complete uptake of extracellular nicotinic acid occurred premid-exponential phase, thereafter small amounts of vitamin B3 were exported back into the medium. Suboptimal levels of nicotinic acid were correlated with slower fermentation and reduced biomass, disrupting redox balance and impeding NAD+ regeneration, thereby affecting metabolite production. Metabolic outcomes varied with nicotinic acid concentrations, linking NAD+ availability to fermentation efficiency. A model was proposed encompassing rapid nicotinic acid uptake, accumulation during cell proliferation, and recycling with limited vitamin B3 export. This research enhances the understanding of nicotinic acid uptake dynamics during grape juice-like fermentation. These insights contribute to advancing yeast metabolism research and have profound implications for the enhancement of biotechnological practices and the wine-making industry.


Asunto(s)
Fermentación , NAD , Niacina , Oxidación-Reducción , Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolismo , Niacina/metabolismo , NAD/metabolismo , Etanol/metabolismo , Coenzimas/metabolismo
18.
J Mol Endocrinol ; 73(1)2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38564418

RESUMEN

The estrogen receptor-α (ER) drives 75% of breast cancers. On activation, the ER recruits and assembles a 1-2 MDa transcriptionally active complex. These complexes can modulate tumour growth, and understanding the roles of individual proteins within these complexes can help identify new therapeutic targets. Here, we present the discovery of ER and ZMIZ1 within the same multi-protein assembly by quantitative proteomics, and validated by proximity ligation assay. We characterise ZMIZ1 function by demonstrating a significant decrease in the proliferation of ER-positive cancer cell lines. To establish a role for the ER-ZMIZ1 interaction, we measured the transcriptional changes in the estrogen response post-ZMIZ1 knockdown using an RNA-seq time-course over 24 h. Gene set enrichment analysis of the ZMIZ1-knockdown data identified a specific delay in the response of estradiol-induced cell cycle genes. Integration of ENCODE data with our RNA-seq results identified that ER and ZMIZ1 both bind the promoter of E2F2. We therefore propose that ER and ZMIZ1 interact to enable the efficient estrogenic response at subset of cell cycle genes via a novel ZMIZ1-ER-E2F2 signalling axis. Finally, we show that high ZMIZ1 expression is predictive of worse patient outcome, ER and ZMIZ1 are co-expressed in breast cancer patients in TCGA and METABRIC, and the proteins are co-localised within the nuclei of tumour cell in patient biopsies. In conclusion, we establish that ZMIZ1 is a regulator of the estrogenic cell cycle response and provide evidence of the biological importance of the ER-ZMIZ1 interaction in ER-positive patient tumours, supporting potential clinical relevance.


Asunto(s)
Neoplasias de la Mama , Factor de Transcripción E2F2 , Receptor alfa de Estrógeno , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Receptor alfa de Estrógeno/metabolismo , Receptor alfa de Estrógeno/genética , Femenino , Línea Celular Tumoral , Factor de Transcripción E2F2/metabolismo , Factor de Transcripción E2F2/genética , Proliferación Celular/genética , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Unión Proteica , Regiones Promotoras Genéticas/genética , Transducción de Señal , Ciclo Celular/genética , Pronóstico
19.
Biotechnol Biofuels Bioprod ; 17(1): 46, 2024 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-38520003

RESUMEN

Hydroxylated aromatic compounds exhibit exceptional biological activities. In the biosynthesis of these compounds, three types of hydroxylases are commonly employed: cytochrome P450 (CYP450), pterin-dependent monooxygenase (PDM), and flavin-dependent monooxygenase (FDM). Among these, FDM is a preferred choice due to its small molecular weight, stable expression in both prokaryotic and eukaryotic fermentation systems, and a relatively high concentration of necessary cofactors. However, the catalytic efficiency of many FDMs falls short of meeting the demands of large-scale production. Additionally, challenges arise from the limited availability of cofactors and compatibility issues among enzyme components. Recently, significant progress has been achieved in improving its catalytic efficiency, but have not yet detailed and informative viewed so far. Therefore, this review emphasizes the advancements in FDMs for the biosynthesis of hydroxylated aromatic compounds and presents a summary of three strategies aimed at enhancing their catalytic efficiency: (a) Developing efficient enzyme mutants through protein engineering; (b) enhancing the supply and rapid circulation of critical cofactors; (c) facilitating cofactors delivery for enhancing FDMs catalytic efficiency. Furthermore, the current challenges and further perspectives on improving catalytic efficiency of FDMs are also discussed.

20.
New Phytol ; 242(3): 881-902, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38433319

RESUMEN

In this review, we untangle the physiological key functions of the essential micronutrients and link them to the deficiency responses in plants. Knowledge of these responses at the mechanistic level, and the resulting deficiency symptoms, have improved over the last decade and it appears timely to review recent insights for each of them. A proper understanding of the links between function and symptom is indispensable for an accurate and timely identification of nutritional disorders, thereby informing the design and development of sustainable fertilization strategies. Similarly, improved knowledge of the molecular and physiological functions of micronutrients will be important for breeding programmes aiming to develop new crop genotypes with improved nutrient-use efficiency and resilience in the face of changing soil and climate conditions.


Asunto(s)
Micronutrientes , Fitomejoramiento , Plantas , Suelo
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