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1.
Nucleic Acids Res ; 52(16): 9586-9595, 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39011897

RESUMEN

FANCJ/BRIP1, initially identified as DOG-1 (Deletions Of G-rich DNA) in Caenorhabditis elegans, plays a critical role in genome integrity by facilitating DNA interstrand cross-link repair and resolving G-quadruplex structures. Its function is tightly linked to a conserved [4Fe-4S] cluster-binding motif, mutations of which contribute to Fanconi anemia and various cancers. This study investigates the critical role of the iron-sulfur (Fe-S) cluster in DOG-1 and its relationship with the cytosolic iron-sulfur protein assembly targeting complex (CTC). We found that a DOG-1 mutant, expected to be defective in Fe-S cluster binding, is primarily localized in the cytoplasm, leading to heightened DNA damage sensitivity and G-rich DNA deletions. We further discovered that the deletion of mms-19, a nonessential CTC component, also resulted in DOG-1 sequestered in cytoplasm and increased DNA damage sensitivity. Additionally, we identified that CIAO-1 and CIAO-2B are vital for DOG-1's stability and repair functions but unlike MMS-19 have essential roles in C. elegans. These findings confirm the CTC and Fe-S cluster as key elements in regulating DOG-1, crucial for genome integrity. Additionally, this study advances our understanding of the CTC's role in Fe-S protein regulation and development in C. elegans, offering a model to study its impact on multicellular organism development.


Asunto(s)
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Daño del ADN , Proteínas del Grupo de Complementación de la Anemia de Fanconi , Proteínas Hierro-Azufre , Animales , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas Hierro-Azufre/metabolismo , Proteínas Hierro-Azufre/genética , Proteínas del Grupo de Complementación de la Anemia de Fanconi/metabolismo , Proteínas del Grupo de Complementación de la Anemia de Fanconi/genética , Citoplasma/metabolismo , Reparación del ADN , Mutación , Proteínas de Unión al ADN/metabolismo , Proteínas de Unión al ADN/genética , ADN Helicasas
2.
J Biol Chem ; 295(6): 1598-1612, 2020 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-31914404

RESUMEN

Benzylisoquinoline alkaloids (BIAs) are a major class of plant metabolites with many pharmacological benefits. Sacred lotus (Nelumbo nucifera) is an ancient aquatic plant of medicinal value because of antiviral and immunomodulatory activities linked to its constituent BIAs. Although more than 30 BIAs belonging to the 1-benzylisoquinoline, aporphine, and bisbenzylisoquinoline structural subclasses and displaying a predominant R-enantiomeric conformation have been isolated from N. nucifera, its BIA biosynthetic genes and enzymes remain unknown. Herein, we report the isolation and biochemical characterization of two O-methyltransferases (OMTs) involved in BIA biosynthesis in sacred lotus. Five homologous genes, designated NnOMT1-5 and encoding polypeptides sharing >40% amino acid sequence identity, were expressed in Escherichia coli Functional characterization of the purified recombinant proteins revealed that NnOMT1 is a regiospecific 1-benzylisoquinoline 6-O-methyltransferase (6OMT) accepting both R- and S-substrates, whereas NnOMT5 is mainly a 7-O-methyltransferase (7OMT), with relatively minor 6OMT activity and a strong stereospecific preference for S-enantiomers. Available aporphines were not accepted as substrates by either enzyme, suggesting that O-methylation precedes BIA formation from 1-benzylisoquinoline intermediates. Km values for NnOMT1 and NnOMT5 were 20 and 13 µm for (R,S)-norcoclaurine and (S)-N-methylcoclaurine, respectively, similar to those for OMTs from other BIA-producing plants. Organ-based correlations of alkaloid content, OMT activity in crude extracts, and OMT gene expression supported physiological roles for NnOMT1 and NnOMT5 in BIA metabolism, occurring primarily in young leaves and embryos of sacred lotus. In summary, our work identifies two OMTs involved in BIA metabolism in the medicinal plant N. nucifera.


Asunto(s)
Bencilisoquinolinas/metabolismo , Metiltransferasas/metabolismo , Nelumbo/enzimología , Proteínas de Plantas/metabolismo , Alcaloides/metabolismo , Secuencia de Aminoácidos , Vías Biosintéticas , Metiltransferasas/química , Metiltransferasas/genética , Metiltransferasas/aislamiento & purificación , Nelumbo/química , Nelumbo/genética , Nelumbo/metabolismo , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/genética , Proteínas de Plantas/aislamiento & purificación , Alineación de Secuencia
3.
Molecules ; 23(11)2018 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-30404216

RESUMEN

Sacred lotus (Nelumbo nucifera Gaertn.) is an ancient aquatic plant used throughout Asia for its nutritional and medicinal properties. Benzylisoquinoline alkaloids (BIAs), mostly within the aporphine and bisbenzylisoquinoline structural categories, are among the main bioactive constituents in the plant. The alkaloids of sacred lotus exhibit promising anti-cancer, anti-arrhythmic, anti-HIV, and anti-malarial properties. Despite their pharmacological significance, BIA metabolism in this non-model plant has not been extensively investigated. In this review, we examine the diversity of BIAs in sacred lotus, with an emphasis on the distinctive stereochemistry of alkaloids found in this species. Additionally, we discuss our current understanding of the biosynthetic genes and enzymes involved in the formation of 1-benzylisoquinoline, aporphine, and bisbenzylisoquinoline alkaloids in the plant. We conclude that a comprehensive functional characterization of alkaloid biosynthetic enzymes using both in vitro and in vivo methods is required to advance our limited knowledge of BIA metabolism in the sacred lotus.


Asunto(s)
Alcaloides/biosíntesis , Nelumbo/metabolismo , Genoma de Planta/genética , Metiltransferasas/genética , Metiltransferasas/metabolismo , Nelumbo/genética , Estereoisomerismo
4.
Sci Rep ; 13(1): 2955, 2023 02 20.
Artículo en Inglés | MEDLINE | ID: mdl-36805479

RESUMEN

Benzylisoquinoline alkaloids (BIAs) are a structurally diverse group of plant specialized metabolites found mainly in members of the order Ranunculales, including opium poppy (Papaver somniferum), for which BIA biosynthetic pathways leading to the critical drugs morphine, noscapine, and sanguinarine have been elucidated. Sacred lotus (Nelumbo nucifera), in the order Proteales, accumulates medicinal BIAs in the proaporphine, aporphine, and bisbenzylisoquinoline structural subgroups with a prevalence of R enantiomers, opposed to the dominant S configuration occurring in the Ranunculales. Nevertheless, distinctive BIA biosynthetic routes in sacred lotus have not been explored. In planta labeling experiments and in vitro assays with recombinant enzymes and plant protein extracts showed that dopamine and 4-hydroxyphenylacetaldehyde derived from L-tyrosine serve as precursors for the formation of (R,S)-norcoclaurine in sacred lotus, whereas only (R)-norcoclaurine byproducts are favored in the plant by action of R-enantiospecific methyltransferases and cytochrome P450 oxidoreductases (CYPs). Enzymes responsible for the R-enantiospecific formation of proaporphine (NnCYP80Q1) and bisbenzylisoquinoline (NnCYP80Q2) scaffolds, and a methylenedioxy bridge introduction on aporphine substrates (NnCYP719A22) were identified, whereas additional aspects of the biosynthetic pathways leading to the distinctive alkaloid profile are discussed. This work expands the availability of molecular tools that can be deployed in synthetic biology platforms for the production of high-value alkaloids.


Asunto(s)
Alcaloides , Antineoplásicos , Aporfinas , Bencilisoquinolinas , Nelumbo , Vías Biosintéticas , Extractos Vegetales
5.
J Mass Spectrom ; 56(2): e4683, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33410198

RESUMEN

Benzylisoquinoline alkaloids (BIAs) have profound implications on human health owing to their potent pharmacological properties. Notable naturally occurring BIAs are the narcotic analgesics morphine, the cough suppressant codeine, the potential anticancer drug noscapine, the muscle relaxant papaverine, and the antimicrobial sanguinarine, all of which are produced in opium poppy (Papaver somniferum). Thebaine, an intermediate in the biosynthesis of codeine and morphine, is used in the manufacture of semisynthetic opiates, including oxycodone and naloxone. As the only commercial source of pharmaceutical opiates, opium poppy has been the focus of considerable research to understand BIA metabolism in the plant. The elucidation of several BIA biosynthetic pathways has enabled the development of synthetic biology platforms aimed at the alternative commercial production of valuable phytochemicals in microorganisms. The detection and identification of BIA pathway products and intermediates in complex extracts is essential for the continuing advancement of research in plant specialized metabolism and microbial synthetic biology. Herein, we report the use of liquid chromatography coupled with linear trap quadrupole and high-resolution Orbitrap multistage mass spectrometry to characterize 44 authentic BIAs using collision-induced dissociation (CID), higher-energy collisional dissociation (HCD), and pulsed Q collision-induced dissociation (PQD) MS2 fragmentation, with MS2 CID followed by MS3 and MS4 fragmentation. Our deep library of diagnostic spectral data constitutes a valuable resource for BIAs identification. In addition, we identified 22 BIAs in opium poppy latex and roots extracts.

6.
Environ Sci Pollut Res Int ; 23(4): 3747-57, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26498813

RESUMEN

The quality of the indoor air can provide very useful information for the artwork conservation. The aim of the study was to evaluate the microbial concentration inside six document repositories of the National Archive of the Republic of Cuba in two months of 1 year. The repositories are large, high, and have a natural cross-ventilation system. The microbial sampling was done in July 2010 (summer or rainy month) and February 2011 (winter or dry month) using the SAS Super 100 biocollector at 100 L/min. An appropriate selective culture media were used to isolate fungi and bacteria. A high total microbial concentration on the north side of the building in two studied months was observed. The fungal concentrations were significantly higher in July 2010 in all repositories, while the bacterial concentrations were significantly higher mostly in February 2011 only in repositories located on the first and second floor of the building. Eight fungal genera in the indoor air of all environments were isolated. Regardless of the side of the analyzed building, Penicillium, Aspergillus, and Cladosporium were the predominant genera. Aspergillus flavus and Aspergillus niger were the species isolated in almost all of the analyzed repositories in the studied months. Gram-positive bacteria prevailed among bacterial groups isolated from indoor air repositories, and some percentages corresponded to the genera Bacillus and Streptomyces. In Cuba, the temperature and relative humidity are high during the whole year but the natural ventilation plays an important role in retarding microbial growth on materials.


Asunto(s)
Microbiología del Aire/normas , Contaminación del Aire Interior/análisis , Archivos , Monitoreo del Ambiente/métodos , Ventilación , Bacillus/aislamiento & purificación , Cuba , Hongos Mitospóricos/aislamiento & purificación , Papel , Estaciones del Año , Streptomyces/aislamiento & purificación , Ventilación/métodos
7.
Bol. latinoam. Caribe plantas med. aromát ; 17(1): 1-16, ene. 2018. ilus, tab
Artículo en Inglés | LILACS | ID: biblio-914977

RESUMEN

Environmental exposure to genotoxic agents represents a major health concern for modern society. DNA damage could lead to mutations, which accumulative effect is closely related to degenerative and lethal diseases, such as cancer. Because of their structural and chemical diversity natural products play a fundamental role in pharmaceutical sciences for novel drug discovery. The present review article focuses on pre-clinical studies done with some species from Cuban flora that have been tested with positive antigenotoxic properties against different genotoxins. Special emphasis regarding molecular mechanisms suggested, from antioxidant activity to DNA repair modulation, a critical discussion of the state of art and the perspectives in the use of these plants as a new and promising strategy for genoprotection in the 21st Century are included.


La exposición ambiental a agentes genotóxicos representa un problema de salud significativo en la sociedad actual. El daño al ADN puede generar mutaciones, cuyo efecto acumulativo se encuentra estrechamente relacionado con enfermedades degenerativas y letales como el cáncer. Debido a su diversidad estructural y química los productos naturales juegan un papel fundamental en las ciencias farmacéuticas en el descubrimiento de nuevas drogas. El presente artículo de revisión puntualiza estudios pre-clínicos realizados con determinadas especies de la flora cubana que han sido estudiadas con una respuesta antioxidante positiva frente a diferentes genotoxinas. Se enfatizan especialmente los mecanismos moleculares sugeridos, desde actividad antioxidante hasta modulación de la reparación del ADN, así como una discusión crítica del estado del arte y las perspectivas en el empleo de estas plantas como una estrategia nueva y prometedora para la genoprotección en el siglo 21.


Asunto(s)
Daño del ADN/efectos de los fármacos , Phyllanthus/química , Mangifera/química , Cymbopogon/química , Antioxidantes/farmacología , Cuba
8.
ISRN Microbiol ; 2012: 680598, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23762758

RESUMEN

Documentary heritage is permanently subject to suffering from physical, chemical, and/or biological alterations. Biological deterioration by microorganisms (bacteria and fungi) causes undesirable changes on material properties. Microorganisms affect different organic, natural or synthetic substrates (cellulose, polycarbonates), metals, and compounds of optical and magnetic devices (CD, VHS). Paper made by vegetal fibers, functional additives (glue, optical polishers, consolidating agents), and inks with organic bindings are used as sources of nutrients. The environmental microorganisms that form the microbial charge of indoor air at repositories (archives, libraries) storing cultural heritage can deteriorate the different supports of heritage importance and affect human health as allergies and skin affections. The aims of this research were to study microbial contamination of the environment and its influence on biodeterioration by the biofilm formation and to analyze the relationship between environment microbiota and biofilm formation in materials stored at three archives in Argentina and in two repositories of the National Archive of the Republic of Cuba.

9.
Colloids Surf B Biointerfaces ; 85(2): 229-34, 2011 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-21439796

RESUMEN

The aims of this paper were to study the biofouling and biodeterioration of photos and maps stored at Historical Archive of the Museum of La Plata (HAMP), Argentine, and two repositories of the National Archive of Cuba Republic (NARC) and to carry out the physiological characterization of the isolated fungi and bacteria. The role of the environmental microbiota in the biofouling formation was also studied. Microbial assemblages in the air were sampled by sedimentation technique while those on documents were sampled by swabbering. Biofilm formation and biofouling were monitored by scanning electron microscope (SEM). Large microbial assemblages were found at NARC archives with the prevalence of genera Aspergillus, Cladosporium and Penicillium, whereas at HAMP these values were lower, Penicillium was the only fungal genus detected. Most of the fungi degraded cellulose and produced pigments and acids, and all of the isolated bacteria had proteolytic and/or cellulolytic activity. In all cases, a higher concentration of viable bacteria than of fungi was isolated from documents. These results correlated with bacterial values detected in air at NARC repositories. However, this correlation cannot be observed at HAMP where Aspergillus, Penicillium and Talaromyces helicus (teleomorph of Penicillium) were isolated. It is the first time that the last genus is reported in documents.


Asunto(s)
Bacterias/crecimiento & desarrollo , Incrustaciones Biológicas , Hongos/crecimiento & desarrollo , Museos , Microbiología del Aire , Argentina , Aspergillus/crecimiento & desarrollo , Aspergillus/aislamiento & purificación , Aspergillus/ultraestructura , Bacillus/crecimiento & desarrollo , Bacillus/aislamiento & purificación , Bacillus/ultraestructura , Bacterias/aislamiento & purificación , Bacterias/ultraestructura , Cladosporium/crecimiento & desarrollo , Cladosporium/aislamiento & purificación , Cladosporium/ultraestructura , Recuento de Colonia Microbiana , Cuba , Enterobacter/crecimiento & desarrollo , Enterobacter/aislamiento & purificación , Enterobacter/ultraestructura , Monitoreo del Ambiente/métodos , Hongos/aislamiento & purificación , Hongos/ultraestructura , Viabilidad Microbiana , Microscopía Electrónica de Rastreo , Papel , Penicillium/crecimiento & desarrollo , Penicillium/aislamiento & purificación , Penicillium/ultraestructura , Serratia/crecimiento & desarrollo , Serratia/aislamiento & purificación , Serratia/ultraestructura , Staphylococcus/crecimiento & desarrollo , Staphylococcus/aislamiento & purificación , Staphylococcus/ultraestructura , Streptococcus/crecimiento & desarrollo , Streptococcus/aislamiento & purificación , Streptococcus/ultraestructura , Streptomyces/crecimiento & desarrollo , Streptomyces/aislamiento & purificación , Streptomyces/ultraestructura
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