Publications by authors named "Nikolai Ivanov"

The Solanaceae plant family contains at least 98 genera and over 2700 species. The genus stands out for its ability to produce pyridine and tropane alkaloids, which are relatively poorly characterized at the phytochemical level. In this study, we analyzed dried leaves of using supercritical CO extraction and ultra-high-pressure liquid chromatography coupled to high-resolution tandem mass spectrometry, followed by feature-based molecular networking.

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Cigarette smoking is a major preventable cause of morbidity and mortality. While quitting smoking is the best option, switching from cigarettes to non-combustible alternatives (NCAs) such as e-vapor products is a viable harm reduction approach for smokers who would otherwise continue to smoke. A key challenge for the clinical assessment of NCAs is that self-reported product use can be unreliable, compromising the proper evaluation of their risk reduction potential.

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The Solanaceae species Nicotiana tabacum, an economically important crop plant cultivated worldwide, is an allotetraploid species that appeared about 200,000 years ago as the result of the hybridization of diploid ancestors of Nicotiana sylvestris and Nicotiana tomentosiformis. The previously published genome assemblies for these three species relied primarily on short-reads, and the obtained pseudochromosomes only partially covered the genomes. In this study, we generated annotated de novo chromosome-level genomes of N.

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-mediated transformation leads to the formation of crown galls or hairy roots on infected plants. These effects develop due to the activity of T-DNA genes, gathered on a big plasmid, acquired from agrobacteria during horizontal gene transfer. However, a lot of plant species are known to contain such sequences, called cellular T-DNAs (cT-DNAs), and maintain normal phenotypes.

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is a large and diverse tree genus in the Myrtaceae family. Genome assemblies for clove (, 370 Mb) and sea apple (, 405 Mb) provided the first insights into the genomic features and evolution of the genus. Here, we present additional chromosome-scale genome assemblies for , and Genome profiling analyses show that , like and , is diploid (2n = 2x = 22), while the , , and specimens are autotetraploid (2n = 4x = 44).

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Background: Anatabine, although being one of four major tobacco alkaloids, is never accumulated in high quantity in any of the naturally occurring species from the Nicotiana genus. Previous studies therefore focused on transgenic approaches to synthetize anatabine, most notably by generating transgenic lines with suppressed putrescine methyltransferase (PMT) activity. This led to promising results, but the global gene expression of plants with such distinct metabolism has not been analyzed.

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Bacteriophage T3 encodes a SAMase that, through cleavage of S-adenosyl methionine (SAM), circumvents the SAM-dependent type I restriction-modification (R-M) defense. We show that SAMase also allows T3 to evade the BREX defense. Although SAM depletion weakly affects BREX methylation, it completely inhibits the defensive function of BREX, suggesting that SAM could be a co-factor for BREX-mediated exclusion of phage DNA, similar to its anti-defense role in type I R-M.

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SQUAMOSA PROMOTER BINDING-LIKE (SPL) proteins constitute a large family of transcription factors known to play key roles in growth and developmental processes, including juvenile-to-adult and vegetative-to-reproductive phase transitions. This makes SPLs interesting targets for precision breeding in plants of the Nicotiana genus used as e.g.

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Article Synopsis
  • - This study investigates the evolutionary relationships among a group of allopolyploid tobacco species from Australia, focusing on their hybrid origins from diploid relatives using genetic analysis.
  • - Researchers conducted a detailed analysis of plastid genomes and nuclear gene families, finding that the section is a monophyletic group and identifying the maternal ancestor in the hybridization process.
  • - The findings suggest that the section originated from hybridization between two ancestral species, contributing to a better understanding of polyploid species evolution through comprehensive genomic data.
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Acclimation to different light regimes is at the basis of survival for photosynthetic organisms, regardless of their evolutionary origin. Previous research efforts largely focused on acclimation events occurring at the level of the photosynthetic apparatus and often highlighted species-specific mechanisms. Here, we investigated the consequences of acclimation to different irradiances in Chlorella vulgaris, a green alga that is one of the most promising species for industrial application, focusing on both photosynthetic and mitochondrial activities.

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A growing body of evidence links gut microbiota changes with inflammatory bowel disease (IBD), raising the potential benefit of exploiting metagenomics data for non-invasive IBD diagnostics. The sbv IMPROVER metagenomics diagnosis for inflammatory bowel disease challenge investigated computational metagenomics methods for discriminating IBD and nonIBD subjects. Participants in this challenge were given independent training and test metagenomics data from IBD and nonIBD subjects, which could be wither either raw read data (sub-challenge 1, SC1) or processed Taxonomy- and Function-based profiles (sub-challenge 2, SC2).

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Tobacco smoke delivers a complex mixture of hazardous and potentially hazardous chemicals. Some of these may induce the formation of DNA mutations, which increases the risk of various cancers that display characteristic patterns of accumulated mutations arising from the causative exposures. Tracking the contributions of individual mutagens to mutational signatures present in human cancers can help understand cancer etiology and advance disease prevention strategies.

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Chemical modifications to DNA bases, including DNA adducts arising from reactions with electrophilic chemicals, are well-known to impact cell growth, miscode during replication, and influence disease etiology. However, knowledge of how genomic sequences and structures influence the accumulation of alkylated DNA bases is not broadly characterized with high resolution, nor have these patterns been linked with overall quantities of modified bases in the genome. For benzo(a) pyrene (BaP), a ubiquitous environmental carcinogen, we developed a single-nucleotide resolution damage sequencing method to map in a human lung cell line the main mutagenic adduct arising from BaP.

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Clozapine is an atypical antipsychotic drug used to treat treatment-resistant schizophrenia. Its side effects, including liver enzyme abnormalities, experienced by many patients preclude its more common use as a first-line therapy for schizophrenia. Toxicoproteomic approaches have been demonstrated to effectively guide the identification of toxicological mechanisms.

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Lipids play a vital role as essential components of all prokaryotic and eukaryotic cells. Constant technological improvements in mass spectrometry have made lipidomics a powerful analytical tool for monitoring tissue lipidome compositions in homeostatic as well as disease states. This paper presents a step-by-step protocol for a shotgun lipid analysis method that supports the simultaneous detection and quantification of a few hundred molecular lipid species in different tissue and biofluid samples at high throughput.

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Anatabine, an alkaloid present in plants of the family (including tobacco and eggplant), has been shown to ameliorate chronic inflammatory conditions in mouse models, such as Alzheimer's disease, Hashimoto's thyroiditis, multiple sclerosis, and intestinal inflammation. However, the mechanisms of action of anatabine remain unclear. To understand the impact of anatabine on cellular systems and identify the molecular pathways that are perturbed, we designed a study to examine the concentration-dependent effects of anatabine on various cell types by using a systems pharmacology approach.

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There is an increasingly urgent call to shift industrial processes from fossil fuel feedstock to sustainable bio-based resources. This change becomes of high importance considering new budget requirements for a carbon-neutral economy. Such a transformation can be driven by traditionally used plants that are able to produce large amounts of valuable biologically relevant secondary metabolites.

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Inhalation as a route for administering drugs and dietary supplements has garnered significant attention over the past decade. We performed real-time analyses of aerosols using secondary electrospray ionization (SESI) technology interfaced with high-resolution mass spectrometry (HRMS), primarily developed for exhaled breath analysis with the goal to detect the main aerosol constituents. Several commercially available inhalation devices containing caffeine, melatonin, cannabidiol, and vitamin B12 were tested.

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Article Synopsis
  • The research evaluated the performance of 21 metagenomics software pipelines for identifying microbial compositions across various datasets.
  • Most pipelines had consistently strong results at the phylum level, but varied more at the genus and species levels; kmer-based pipelines (like Kraken and CLARK-S) generally performed best.
  • Using adaptive filtering methods based on the sample's diversity improved the accuracy of these pipelines by increasing precision while managing the tradeoff with recall.
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In tobacco, the homologous ETHYLENE RESPONSE FACTOR (ERF) transcription factors ERF199 and ERF189 coordinate the transcription of multiple metabolic genes involved in nicotine biosynthesis. Natural alleles at the NIC1 and NIC2 loci greatly affect alkaloid accumulation and overlap with ERF199 and ERF189 in the tobacco genome, respectively. In this study, we identified several low-nicotine tobacco varieties lacking ERF199 or ERF189 from a tobacco germplasm collection.

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The clove (Syzygium aromaticum) is an important tropical spice crop in global trade. Evolving environmental pressures necessitate modern characterization and selection techniques that are currently inaccessible to clove growers owing to the scarcity of genomic and genetic information. Here, we present a 370-Mb high-quality chromosome-scale genome assembly for clove.

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Most flavors used in e-liquids are generally recognized as safe for oral consumption, but their potential effects when inhaled are not well characterized. In vivo inhalation studies of flavor ingredients in e-liquids are scarce. A structure-based grouping approach was used to select 38 flavor group representatives (FGR) on the basis of known and in silico-predicted toxicological data.

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Article Synopsis
  • A/J mice are commonly used in research to study lung tumor formation and progression, revealing challenges in distinguishing between lung tumors caused by cigarette smoke and those that occur spontaneously with age.
  • An 18-month study compared exposure to tobacco heating systems and conventional cigarette smoke, leading to the development of a 13-gene signature that effectively differentiated between tumors caused by smoke exposure and spontaneous tumors in mice.
  • This gene signature not only proved effective in mouse models but also showed potential for human application by distinguishing between lung cancer in smokers and non-smokers, which could help identify patients who would benefit from targeted treatments.
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Article Synopsis
  • The text discusses the necessity of developing genome editing technologies to identify key genes involved in how crops respond to environmental stress factors, particularly focusing on abscisic acid (ABA) receptors in plants.* -
  • It highlights the challenges of working with polyploid plants due to their complex gene structures, specifically mentioning a biotechnological crop amenable to CRISPR/Cas9 techniques for analyzing its 23 ABA receptor family members.* -
  • Results from the research showed that mutants lacking certain ABA receptors exhibited insensitivity to ABA in seed growth and development but maintained normal transpiration control, suggesting a strong regulatory system evolved from their harsh environmental origins.*
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