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1.
Nat Commun ; 14(1): 552, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36725855

RESUMO

The degradation process of RNA is decisive in guaranteeing high-fidelity translation of genetic information in living organisms. However, visualizing the single-base degradation process in real time and deciphering the degradation mechanism at the single-enzyme level remain formidable challenges. Here, we present a reliable in-situ single-PNPase-molecule dynamic electrical detector based on silicon nanowire field-effect transistors with ultra-high temporal resolution. These devices are capable of realizing real-time and label-free monitoring of RNA analog degradation with single-base resolution, including RNA analog binding, single-nucleotide hydrolysis, and single-base movement. We discover a binding event of the enzyme (near the active site) with the nucleoside, offering a further understanding of the RNA degradation mechanism. Relying on systematic analyses of independent reads, approximately 80% accuracy in RNA nucleoside sequencing is achieved in a single testing process. This proof-of-concept sets up a Complementary Metal Oxide Semiconductor (CMOS)-compatible playground for the development of high-throughput detection technologies toward mechanistic exploration and single-molecule sequencing.


Assuntos
Exonucleases , Nucleosídeos , RNA , Análise de Sequência de RNA , Estabilidade de RNA
2.
Zhongguo Zhong Yao Za Zhi ; 48(1): 114-125, 2023 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-36725264

RESUMO

Galli Gigerii Endothelium Corneum(GGEC), the dried gizzard membrane of Gallus gallus domesticus is a Chinese medicinal material commonly used for digestion. However, due to the particularity of texture and composition, its active ingre-dients have not been clarified so far, and there is also a lack of quality evaluation indicators. In this study, UPLC-Q-TOF-MS was used to analyze the chemical components from the water extract of GGEC, and ten nucleosides were identified for the first time. HPLC fingerprints of the water extracts of GGEC were established and the content of seven nucleosides was determined. The fingerprint similarities of 40 batches of GGEC samples ranged from 0.765 to 0.959, indicating that there were great differences among the GGEC products processed with different methods. In addition, SPSS 22.0 and SIMCA 14.1 were used for hierarchical cluster analysis(HCA) and principal component analysis(PCA) on the 19 common peaks of the HPLC fingerprints of GGEC, and the 40 batches of samples were divided into three categories: raw GGEC, fried GGEC and vinegar-processed GGEC. Eight differential components in GGEC were marked by orthogonal partial least squares discrimination analysis(OPLS-DA), two of which were adenine and thymine. The results of content determination showed that the total content of the seven nucleosides in raw GGEC, fried GGEC and vinegar-processed GGEC were 182.5-416.8, 205.3-368.7, and 194.2-283.0 µg·g~(-1), respectively. There were significant differences in the content of hypoxanthine, thymine and thymidine among the GGEC products processed with different methods(P<0.05), which were graded in the order of fried GGEC>vinegar-processed GGEC>raw GGEC. This suggested that the content of hypoxanthine, thymine and thymidine tended to increase during the frying process, and the variation range might be related to the degree of heat exposure. The established methods in this study were simple and reproducible, and could be used for qualitative and quantitative analysis of GGEC and its processed pro-ducts. This study also provided reference for the establishment of quality standards of GGEC with chemical components as control index.


Assuntos
Medicamentos de Ervas Chinesas , Nucleosídeos , Medicamentos de Ervas Chinesas/química , Cromatografia Líquida de Alta Pressão , Ácido Acético , Timina , Timidina , Água , Hipoxantinas
3.
Open Biol ; 13(1): 220234, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36629018

RESUMO

The phosphorylation of nucleosides and their polymerization are crucial issues concerning the origin of life. The question of how these plausible chemical processes took place in the prebiotic Earth is still perplexing, despite several studies that have attempted to explain these prebiotic processes. The purpose of this article is to review these chemical reactions with respect to chemical evolution in the primeval Earth. Meanwhile, from our perspective, the chiral properties and selection of biomolecules should be considered in the prebiotic chemical origin of life, which may contribute to further research in this field to some extent.


Assuntos
Nucleosídeos , Origem da Vida , Nucleosídeos/química , Fosforilação , Polimerização , Evolução Química
4.
Open Biol ; 13(1): 220287, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36629016

RESUMO

The biosynthetic enzyme, ForT, catalyses the formation of a C-C bond between 4-amino-1H-pyrazoledicarboxylic acid and MgPRPP to produce a C-nucleoside precursor of formycin A. The transformation catalysed by ForT is of chemical interest because it is one of only a few examples in which C-C bond formation takes place via an electrophilic substitution of a small, aromatic heterocycle. In addition, ForT is capable of discriminating between the aminopyrazoledicarboxylic acid and an analogue in which the amine is replaced by a hydroxyl group; a remarkable feat given the steric and electronic similarities of the two molecules. Here we report biophysical measurements, structural biology and quantum chemical calculations that provide a detailed molecular picture of ForT-catalysed C-C bond formation and the conformational changes that are coupled to catalysis. Our findings set the scene for employing engineered ForT variants in the biocatalytic production of novel, anti-viral C-nucleoside and C-nucleotide analogues.


Assuntos
Nucleosídeos , Catálise , Cristalografia por Raios X
5.
Chem Commun (Camb) ; 59(7): 892-895, 2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36594822

RESUMO

Artificial metal-mediated DNA base pairing is a promising strategy for creating highly functionalized DNA supramolecules. Here we report a novel ligand-type triazole-4-carboxylate (TazC) nucleoside that is readily prepared by the click reaction. TazC nucleosides were found to form a stable TazC-CuII-TazC base pair inside DNA duplexes, resulting in CuII-specific duplex stabilization (ΔTm = +7.7 °C). This study demonstrates that the triazole derivatives are useful in the development of metal-mediated base pairing.


Assuntos
Química Click , Nucleosídeos , Nucleosídeos/química , Pareamento de Bases , DNA/química , Metais/química , Ácidos Carboxílicos
6.
Chem Rec ; 23(1): e202200252, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36623938

RESUMO

"The field of nucleosides, nucleotides, and nucleic acids has been in existence for some decades, leading to a notion that the area is well-explored and/or specialized, but is that true? Despite the constant reliance on this field for various aspects of biochemical, biological, and biomedical research, recent advances have brought this area into a greater focus, with the potential and benefits becoming increasingly evident. Explore this Special Collection for rich, diverse, and state-of-the art research presented in the form of Personal Accounts, Reviews, and Research Articles."


Assuntos
Ácidos Nucleicos , Nucleosídeos , Nucleotídeos
7.
J Chromatogr A ; 1689: 463773, 2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36628808

RESUMO

The structural properties of ionic liquid stationary phases have a considerable effect on their separation selectivity. However, the difference of the chromatographic retention behavior of different regioisomeric ionic liquid stationary phases has rarely been investigated. In this study, three regioisomeric ionic liquid silane reagents were prepared by photoinitiated ene-click chemistry and bonded to silica by one-pot method to fabricate three new stationary phases (Sil-C2Im-C8, Sil-C6Im-C4, and Sil-C9Im-C1). All three stationary phases showed promising retention repeatability and efficiency. The retention behavior of the three stationary phases was investigated under various chromatographic conditions. The retention mechanism was further investigated by the linear energy solvation relationship and Van't Hoff plots. The stationary phases exhibited mixed-mode retention mechanisms. The π-π, hydrogen bonding, ion-exchange, and hydrophilic interactions with analytes were the weakest when the imidazole ions were embedded in the innermost part of the alkyl chains, while the interactions were the strongest when the imidazole ions were embedded in the middle of the alkyl chains. The three stationary phases provided great but different separation performances towards nucleosides, nucleobases, aromatic acids, alkyl benzenes, and polycyclic aromatic hydrocarbons due to the influence of imidazole ion position.


Assuntos
Líquidos Iônicos , Cromatografia Líquida/métodos , Líquidos Iônicos/química , Concentração de Íons de Hidrogênio , Nucleosídeos/análise , Imidazóis/química , Interações Hidrofóbicas e Hidrofílicas , Dióxido de Silício/química
8.
Nat Commun ; 14(1): 138, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36627283

RESUMO

ß-Nucleosides and their analogs are dominant clinically-used antiviral and antitumor drugs. α-Nucleosides, the anomers of ß-nucleosides, exist in nature and have significant potential as drugs or drug carriers. Currently, the most widely used methods for synthesizing ß- and α-nucleosides are via N-glycosylation and pentose aminooxazoline, respectively. However, the stereoselectivities of both methods highly depend on the assisting group at the C2' position. Herein, we report an additive-controlled stereodivergent iodocyclization method for the selective synthesis of α- or ß-nucleosides. The stereoselectivity at the anomeric carbon is controlled by the additive (NaI for ß-nucleosides; PPh3S for α-nucleosides). A series of ß- and α-nucleosides are prepared in high yields (up to 95%) and stereoselectivities (ß:α up to 66:1, α:ß up to 70:1). Notably, the introduced iodine at the C2' position of the nucleoside is readily functionalized, leading to multiple structurally diverse nucleoside analogs, including stavudine, an FDA-approved anti-HIV agent, and molnupiravir, an FDA-approved anti-SARS-CoV-2 agent.


Assuntos
Fármacos Anti-HIV , COVID-19 , Humanos , Nucleosídeos , Estereoisomerismo , Antivirais/farmacologia
10.
Anal Chem ; 95(2): 1608-1617, 2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36598775

RESUMO

As RNA post-transcriptional modifications are of growing interest, several methods were developed for their characterization. One of them established for their identification, at the nucleosidic level, is the hyphenation of separation methods, such as liquid chromatography or capillary electrophoresis, to tandem mass spectrometry. However, to our knowledge, no software is yet available for the untargeted identification of RNA post-transcriptional modifications from MS/MS data-dependent acquisitions. Thus, very long and tedious manual data interpretations are required. To meet the need of easier and faster data interpretation, a new user-friendly search engine, called Nucleos'ID, was developed for CE-MS/MS and LC-MS/MS users. Performances of this new software were evaluated on CE-MS/MS data from nucleoside analyses of already well-described Saccharomyces cerevisiae transfer RNA and Bos taurus total tRNA extract. All samples showed great true positive, true negative, and false discovery rates considering the database size containing all modified and unmodified nucleosides referenced in the literature. The true positive and true negative rates obtained were above 0.94, while the false discovery rates were between 0.09 and 0.17. To increase the level of sample complexity, untargeted identification of several RNA modifications from Pseudomonas aeruginosa 70S ribosome was achieved by the Nucleos'ID search following CE-MS/MS analysis.


Assuntos
Nucleosídeos , Espectrometria de Massas em Tandem , Animais , Bovinos , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida/métodos , Nucleosídeos/análise , Ferramenta de Busca , RNA de Transferência
11.
ACS Biomater Sci Eng ; 9(1): 40-61, 2023 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-36524860

RESUMO

Supramolecular hydrogels are of great interest in tissue scaffolding, diagnostics, and drug delivery due to their biocompatibility and stimuli-responsive properties. In particular, nucleosides are promising candidates as building blocks due to their manifold noncovalent interactions and ease of chemical modification. Significant progress in the field has been made over recent years to allow the use of nucleoside-based supramolecular hydrogels in the biomedical field, namely drug delivery and 3D bioprinting. For example, their long-term stability, printability, functionality, and bioactivity have been greatly improved by employing more than one gelator, incorporating different cations, including silver for antibacterial activity, or using additives such as boric acid or even biomolecules. This now permits their use as bioinks for 3D printing to produce cell-laden scaffolds with specified geometries and pore sizes as well as a homogeneous distribution of living cells and bioactive molecules. We have summarized the latest advances in nucleoside-based supramolecular hydrogels. Additionally, we discuss their synthesis, structural properties, and potential applications in tissue engineering and provide an outlook and future perspective on ongoing developments in the field.


Assuntos
Hidrogéis , Engenharia Tecidual , Hidrogéis/química , Nucleosídeos , Tecidos Suporte , Impressão Tridimensional
12.
J Med Chem ; 66(1): 345-370, 2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36529947

RESUMO

CD73 (ecto-5'-nucleotidase) has emerged as an attractive target for cancer immunotherapy of many cancers. CD73 catalyzes the hydrolysis of adenosine monophosphate (AMP) into highly immunosuppressive adenosine that plays a critical role in tumor progression. Herein, we report our efforts in developing orally bioavailable and highly potent small-molecule CD73 inhibitors from the reported hit molecule 2 to lead molecule 20 and then finally to compound 49. Compound 49 was able to reverse AMP-mediated suppression of CD8+ T cells and completely inhibited CD73 activity in serum samples from various cancer patients. In preclinical in vivo studies, orally administered 49 showed a robust dose-dependent pharmacokinetic/pharmacodynamic (PK/PD) relationship that correlated with efficacy. Compound 49 also demonstrated the expected immune-mediated antitumor mechanism of action and was efficacious upon oral administration not only as a single agent but also in combination with either chemotherapeutics or checkpoint inhibitor in the mouse tumor model.


Assuntos
Linfócitos T CD8-Positivos , Neoplasias , Camundongos , Animais , Nucleosídeos , 5'-Nucleotidase , Neoplasias/tratamento farmacológico , Modelos Animais de Doenças , Monofosfato de Adenosina
13.
J Pharm Biomed Anal ; 224: 115199, 2023 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-36527856

RESUMO

Yihuang decoction (YHD) is one of the most famous formulas in tradition Chinese medicine (TCM) and has been clinically used for treatment of vaginitis, pelvic inflammation and other gynecological diseases for hundreds of years. However, its chemical composition remains unclear. In this study, high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (HPLC-Q-TOF-MS) was employed for its chemical profiling investigation. As a result, 90 components were chemically defined, including 23 alkaloids, 14 organic acids, 3 phenylethanoid glycosides, 4 iridoid glycosides, 5 terpenoid lactones, 10 flavonoids, 8 nucleobases and nucleosides, 12 amino acids, and 11 other compounds. In addition, 8 representative compounds (acteoside, allantoin, berberine, 4-O-feruloylquinic acid, 5-O-feruloylquinic acid, gallic acid, geniposidic acid, and phellodendrine) were simultaneously determined in 10 batches of YHD samples by HPLC with a diode array detector (HPLC-DAD). For all the analytes, their calibration curves showed good linearity (R2 >0.9990) within the test ranges. RSDs of precision, repeatability and stability test were all below 3.50%. The overall recoveries ranged from 93.63% to 105.02%, with RSDs less than 3.50%. This study is supposed to exhibit a comprehensive chemical profiling of YHD and to provide some strong basis for quality control and even for action mechanism of this ancient classical prescription.


Assuntos
Medicamentos de Ervas Chinesas , Espectrometria de Massas em Tandem , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem/métodos , Medicamentos de Ervas Chinesas/química , Medicina Tradicional Chinesa , Nucleosídeos
14.
Anal Methods ; 15(2): 203-211, 2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36520082

RESUMO

We have developed a new naphthalimide-based amphiphile (YN-1) for the simultaneous detection of ATP and CTP. In YN-1, the cationic tyrosine-linked polyamine (+2 charge, hydrophilic unit) is appended at the -peri position of naphthalimide (hydrophobic unit). YN-1 and its Boc-protected compound 4 were characterized using state-of-the-art spectroscopic and optical techniques such as NMR, IR, UV-vis and fluorescence. The fluorescence data revealed that YN-1 showed a 'turn-on' (λem = 440 nm) fluorescence response for nanomolar detection of nucleoside triphosphates such as ATP and CTP in 20% HEPES buffer-DMSO solution. YN-1 also showed a concentration-based discrimination between ATP and CTP. YN-1 has been successfully applied for bioimaging of nucleoside triphosphates in MCF-7 live cancer cells with good compatibility. Therefore, the important findings from the present work will provide insight for future development of fluorescent probes to detect various kinds of essential nucleoside triphosphates.


Assuntos
Naftalimidas , Nucleosídeos , Corantes Fluorescentes/química , Trifosfato de Adenosina
15.
Methods Mol Biol ; 2570: 155-173, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36156781

RESUMO

Fluorogenic RNA aptamers are synthetic RNAs that have been evolved by in vitro selection methods to bind and light up conditionally fluorescent organic ligands. Compared with other probes for RNA detection, they are less invasive than hybridization-based methods (FISH, molecular beacons) and are considerably smaller than fluorescent protein-recruiting systems (MS2, Pumilio variants). Fluorogenic aptamers have therefore found widespread use as genetically encodable tags for RNA detection in live cells and have also been used in combination with riboswitches to construct versatile metabolite sensors for in vitro use. Their success builds on a fundamental understanding of their three-dimensional structure to explain the mechanisms of ligand interaction and to rationally design functional aptamer devices. In this protocol, we describe a supramolecular FRET-based structure probing method for fluorogenic aptamers that exploits distance- and orientation-dependent energy transfer efficiencies between site-specifically incorporated fluorescent nucleoside analogs and non-covalently bound ligands, exemplified by 4-cyanoindol riboside (4CI) and the DMHBI+-binding RNA aptamer Chili. This method yields structural restraints that bridge the gap between traditional low-resolution secondary structure probing methods and more elaborate high-resolution methods such as X-ray crystallography and NMR spectroscopy.


Assuntos
Aptâmeros de Nucleotídeos , Riboswitch , Aptâmeros de Nucleotídeos/química , Transferência Ressonante de Energia de Fluorescência , Corantes Fluorescentes/química , Ligantes , Nucleosídeos , RNA/genética
16.
J Proteomics ; 270: 104737, 2023 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-36174950

RESUMO

The exploration of nucleoside changes in human biofluids has profound potential for cancer diagnosis. Herein, we developed a rapid methodology to quantify 17 nucleosides by UHPLC-MS/MS. Five pairs of isomers were successfully separated within 8 min. The ME was mostly eliminated by sample dilution folds of 1000 for urine and 40 for CCS. The optimized method was firstly applied to screen potential nucleoside biomarkers in CCS by comprising bladder cancer cell lines (5637 and T24) and normal human bladder cell line SV-HUC-1 together with student's t-test and OPLS-DA. Nucleosides with significant differences in the supernatant of urine samples were also uncovered comparing BCa with the non-tumor group, as well as a comparison of BCa recurrence group with the non-recurrence group. By intersecting the differential nucleosides in CCS and urine supernatant, and then further confirmed using validation sets, the combination of m3C and m1A with AUC of 0.775 was considered as a potential biomarker for bladder cancer diagnosis. A panel of m3C, m1A, m1G, and m22G was defined as potential biomarkers for bladder cancer prognosis with an AUC of 0.819. Above all, this method provided a new perspective for diagnosis and recurrence monitoring of bladder cancer. SIGNIFICANCE: The exploration of nucleoside changes in body fluids has profound potential for the diagnosis and elucidation of the pathogenesis of cancer. In this study, we developed a rapid methodology for the simultaneous quantitative determination of 17 nucleosides in the supernatant of cells and urine samples using UHPLC-MS/MS to discover and validate bladder cancer related excreted nucleoside biomarkers. The results of this paper provide a new strategy for diagnosis and postoperative recurrence monitoring of bladder cancer and provide theoretical support for the exploration of its pathogenesis.


Assuntos
Líquidos Corporais , Neoplasias da Bexiga Urinária , Humanos , Espectrometria de Massas em Tandem/métodos , Neoplasias da Bexiga Urinária/diagnóstico , Neoplasias da Bexiga Urinária/metabolismo , Nucleosídeos/urina , Cromatografia Líquida/métodos , Cromatografia Líquida de Alta Pressão/métodos , Biomarcadores Tumorais , Líquidos Corporais/metabolismo , Técnicas de Cultura de Células
17.
J Virol ; 97(1): e0172322, 2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36533954

RESUMO

Most human influenza vaccine antigens are produced in fertilized chicken eggs. Recent H3N2 egg-based vaccine antigens have limited effectiveness, partially due to egg-adaptive substitutions that alter the antigenicity of the hemagglutinin (HA) protein. The nucleoside-modified mRNA encapsulated in lipid nanoparticles (mRNA-LNP) vaccine platform is a promising alternative for egg-based influenza vaccines because mRNA-LNP-derived antigens are not subject to adaptive pressures that arise during the production of antigens in chicken eggs. Here, we compared H3N2-specific antibody responses in mice vaccinated with either 3c.2A H3-encoding mRNA-LNP or a conventional egg-based Fluzone vaccine (which included an egg-adapted 3c.2A antigen) supplemented with an MF59-like adjuvant. We tested mRNA-LNP encoding wild-type and egg-adapted H3 antigens. We found that mRNA-LNP encoding wild-type H3 elicited antibodies that neutralized the wild-type 3c.2A H3N2 virus more effectively than antibodies elicited by mRNA-LNP encoding egg-adapted H3 or the egg-based Fluzone vaccine. mRNA-LNP expressing either wild-type or egg-adapted H3 protected mice against infection with the wild-type 3c2.A H3N2, whereas the egg-based Fluzone vaccine did not. We found that both mRNA-LNP vaccines elicited high levels of group 2 HA stalk-reactive antibodies, which likely contributed to protection in vivo. Our studies indicate that nucleoside-modified mRNA-LNP-based vaccines can circumvent problems associated with egg adaptations with recent 3c2.A H3N2 viruses. IMPORTANCE This study shows that the nucleoside-modified mRNA-LNP vaccine platform is a promising alternative for egg-based influenza vaccines. We show that mRNA-LNP vaccines expressing H3 antigens elicit high levels of antibodies in mice and protect against H3N2 influenza virus infection.


Assuntos
Vacinas contra Influenza , Influenza Humana , Humanos , Animais , Camundongos , Vacinas contra Influenza/genética , Vírus da Influenza A Subtipo H3N2/genética , Nucleosídeos , RNA Mensageiro/genética , Anticorpos Antivirais , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Galinhas/genética
18.
Bioorg Chem ; 131: 106325, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36577221

RESUMO

After the fortuitous discovery of the anticancer properties of cisplatin, many Pt(II) complexes have been synthesized, to obtain less toxic leads which could overcome the resistance phenomena. Given the importance of nucleosides and nucleotides as antimetabolites, studying their coordinating properties towards Pt(II) ions is challenging for bioorganic and medicinal chemistry. This review aims to describe the results achieved so far in the aforementioned field, paying particular attention to the synthetic aspects, the chemical-physical characterization, and the biological activities of the nucleoside-based Pt(II) complexes.


Assuntos
Antineoplásicos , Complexos de Coordenação , Antineoplásicos/farmacologia , Antineoplásicos/química , Nucleosídeos/farmacologia , Cisplatino/química , Nucleotídeos , Química Farmacêutica , Complexos de Coordenação/farmacologia
19.
J Mol Evol ; 91(1): 60-75, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36576533

RESUMO

Reduced oxidation state phosphorus compounds may have been brought to the early Earth via meteorites or could have formed through geologic processes. These compounds could have played a role in the origin of biological phosphorus (P, hereafter) compounds. Reduced oxidation state P compounds are generally more soluble in water and are more reactive than orthophosphate and its associated minerals. However, to date no facile routes to generate C-O-P type compounds using reduced oxidation state P compounds have been reported under prebiotic conditions. In this study, we investigate the reactions between reduced oxidation state P compounds-and their oxidized products generated via Fenton reactions-with the nucleosides uridine and adenosine. The inorganic P compounds generated via Fenton chemistry readily react with nucleosides to produce organophosphites and organophosphates, including phosphate diesters via one-pot syntheses. The reactions were facilitated by NH4+ ions and urea as a condensation agent. We also present the results of the plausible stability of the organic compounds such as adenosine in an environment containing an abundance of H2O2. Such results have direct implications on finding organic compounds in Martian environments and other rocky planets (including early Earth) that were richer in H2O2 than O2. Finally, we also suggest a route for the sink of these inorganic P compounds, as a part of a plausible natural P cycle and show the possible formation of secondary phosphate minerals such as struvite and brushite on the early Earth.


Assuntos
Marte , Compostos Organofosforados , Compostos Organofosforados/química , Meio Ambiente Extraterreno , Peróxido de Hidrogênio , Minerais/química , Fosfatos/química , Nucleosídeos , Adenosina
20.
Int J Biol Macromol ; 226: 946-955, 2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36528144

RESUMO

The coronavirus disease 2019 has been ravaging throughout the world for three years and has severely impaired both human health and the economy. The causative agent, severe acute respiratory syndrome coronavirus 2 employs the viral RNA dependent RNA polymerase (RdRp) complex for genome replication and transcription, making RdRp an appealing target for antiviral drug development. Systematic characterization of RdRp will undoubtedly aid in the development of antiviral drugs targeting RdRp. Here, our research reveals that RdRp can recognize and utilize nucleoside diphosphates as a substrate to synthesize RNA with an efficiency of about two thirds of using nucleoside triphosphates as a substrate. Nucleoside diphosphates incorporation is also template-specific and has high fidelity. Moreover, RdRp can incorporate ß-d-N4-hydroxycytidine into RNA while using diphosphate form molnupiravir as a substrate. This incorporation results in genome mutation and virus death. It is also observed that diphosphate form molnupiravir is a better substrate for RdRp than the triphosphate form molnupiravir, presenting a new strategy for drug design.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/metabolismo , RNA , Difosfatos , Nucleosídeos , RNA Polimerase Dependente de RNA/metabolismo , Antivirais/química , Nucleotídeos , RNA Viral/genética , Proteínas do Olho , Proteínas do Tecido Nervoso
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